JP2006059867A - Photoelectric conversion header, lsi package with interface module, manufacturing method of photoelectric conversion header, and optical wiring system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an optical component from being broken during manufacturing and assembling because of its simple structure, to suppress return optical noise and obtain cost reduction and high performance. <P>SOLUTION: The photoelectric conversion header is provided with a ferrule 1 to hold and position an optical waveguide 5 so that the optical input and output end of the optical waveguide projects from a component mounting surface, electric wiring 2 formed on the component mounting surface of the ferrule 1, and a plane type optical component 3 which is mounted to the component mounting surface of the ferrule 1 and electrically connected with electric wiring 2. The optical input and output end projecting from the component mounting surface of the ferrule 1 of the optical waveguide 5 is formed with an end face almost vertical to the optical waveguide direction of the optical waveguide 5, and the component mounting surface of the ferrule 1 is displaced by two degrees or more from a face vertical to the optical waveguide direction of the optical waveguide 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photoelectric conversion header applied to a high-speed LSI package and the like, a manufacturing method thereof, an LSI package with an interface module on which the photoelectric conversion header is mounted, and an optical wiring system.

  In recent years, the performance of electronic devices such as bipolar transistors and field effect transistors has been improved, and the operating speed of large scale integrated circuits (LSIs) has been dramatically improved. However, even if the internal operation of the LSI is increased, the operation speed on the printed circuit board on which the LSI is mounted is kept lower than the internal operation of the LSI. This is due to the increase in transmission loss, noise, and electromagnetic interference of the electrical wiring accompanying the increase in the operating frequency, and the necessity of keeping the operating frequency lower for longer wirings in order to ensure signal quality. That is, in the electrical wiring apparatus, the tendency that the mounting technology dominates the system speed rather than the LSI operating speed has been increasing in recent years.

  In view of the problem of such an electrical wiring device, several optical wiring devices for connecting LSIs with light have been proposed. Since optical wiring has almost no frequency dependency of loss at a frequency of 100 GHz or more from direct current, and there is no electromagnetic interference in the wiring path or ground potential fluctuation noise, wiring of several tens of Gbps can be easily realized. As this type of inter-LSI optical wiring, there has been proposed a structure in which an interface module for externally wiring high-speed signals is directly mounted on an interposer on which a signal processing LSI is mounted (see, for example, Non-Patent Document 1).

In order to configure the optical wiring as in Non-Patent Document 1 or the like, a photoelectric conversion component is indispensable, and a small photoelectric conversion component is required for mounting on an interposer or the like. As this small photoelectric conversion component, an optical fiber and a surface emitting laser are optically coupled (for example, see Patent Document 1), or a block body having metal protrusions and inclined surfaces with different heights, and an optical element is tilted. For example, there are proposed ones in which the return light is suppressed (for example, see Patent Document 2), and back-illuminated photodiodes (PD) bonded to an oblique fiber (for example, see Patent Document 3).
JP 2000-347072 A JP 2001-281503 A JP 2001-284608 A Nikkei Electronics 810, pp.121-122, December 3, 2001

  However, in the conventional example of Patent Document 1, when an optical fiber is inserted and assembled because of optical coupling between the optical fiber and the surface emitting laser, there is a problem that the optical fiber hits an active region of the optical element and is easily damaged. Further, since the optical fiber and the surface emitting laser are arranged close to each other in parallel, there is a problem that the surface emitting laser is likely to generate so-called return light noise.

  Patent Document 2 discloses a conventional example for suppressing the above-mentioned return light noise. In this example, a block body having metal protrusions and inclined surfaces having different heights is used to incline the optical element, and the length due to thermal expansion thereof is used. Since the change is different in the plane, there is a problem that the tilt angle of the optical element is likely to vary with respect to the temperature change. Therefore, in the conventional example of Patent Document 2, return optical noise may still occur depending on the temperature. In order to avoid this, it is necessary to make the tilt angle excessively large. In addition, since the tilt angle is set excessively, there is a problem that the optical coupling efficiency between the surface emitting laser and the optical fiber becomes excessively low. Furthermore, the conventional example of Patent Document 2 has a complicated configuration, and the problem in terms of manufacturing yield is not small.

  In the conventional example of Patent Document 2, since the entire optical element is inclined with respect to the optical fiber support member, a gap corresponding to the amount obtained by multiplying the length from the optical element end to the active region by the inclination angle is different from that of the optical fiber. A high-speed light-receiving element that occurs between the optical elements and needs to reduce the light-receiving diameter has a problem that the optical coupling efficiency tends to decrease due to the spread of the emitted light from the optical fiber. At first glance, it seems that the light receiving element is not so much related to the return light noise, but in the case of a relatively short distance (up to about 1 m) wiring such as wiring between LSIs, reflection on the end face of the optical fiber on the light receiving element side or light receiving element. Most of the light due to reflection on the surface returns to the light emitting element through the optical fiber, which also induces return optical noise. Therefore, the light receiving element side also needs to take a countermeasure against reflected light. In the conventional example of Patent Document 2, it is necessary to tilt the light receiving element, which is a problem that the optical coupling efficiency cannot be avoided.

  As another method for inclining the optical element, there is a method in which the end face of the fiber is slanted with the ferrule and the optical element is bonded as in Patent Document 3, but this method is used for shaping the end face of the optical fiber (slanting). A polishing step was essential, and it was substantially difficult to significantly reduce costs. In applications such as inter-LSI wiring, there is a problem that the cost allowed is dramatically lower than that of optical communication, LAN, etc., and a long process such as a polishing process cannot be allowed.

  The present invention has been made in consideration of the above circumstances, and its object is to prevent damage to the optical element during manufacturing and assembly with a simple structure, and at the same time, to reduce the return light noise, thereby reducing the cost. And a high-performance photoelectric conversion header, an LSI package with an interface module using the same, and an optical wiring system.

  Moreover, the other object of this invention is to provide the manufacturing method of the photoelectric conversion header for manufacturing said photoelectric conversion header.

  In order to solve the above problems, the present invention adopts the following configuration.

  That is, one embodiment of the present invention includes an optical waveguide, a ferrule that holds and positions the optical waveguide so that the light input / output end of the optical waveguide protrudes at least partially from the element mounting surface, and the ferrule A photoelectric conversion header comprising at least an electric wiring provided on an element mounting surface and a planar optical element mounted on the element mounting surface of the ferrule and electrically connected to the electric wiring; The light input / output end projecting at least partly from the element mounting surface of the ferrule has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the element mounting surface of the ferrule is the optical waveguide of the optical waveguide. It is characterized in that the surface is shifted by 2 degrees or more from the surface perpendicular to the wave direction.

  According to another aspect of the present invention, a planar optical element composed of a planar light emitting element or a planar light receiving element, an optical waveguide that guides light, a ferrule that holds and positions the optical waveguide, A photoelectric conversion header provided with an electrical wiring provided on the ferrule, wherein the electrical wiring is at least of the ferrule from a surface where an optical input / output end of the optical waveguide held by the ferrule of the ferrule is exposed. Formed over one side surface, and the planar optical element is mounted on the surface of the ferrule where the optical input / output end of the optical waveguide held by the ferrule is exposed and electrically connected to the electrical wiring, The light input / output end exposed on the surface type optical element mounting surface of the ferrule of the optical waveguide has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the ferrule of the ferrule holds The surface where the light input / output end of the optical waveguide is exposed is a surface shifted by 2 degrees or more from the surface perpendicular to the optical waveguide direction of the optical waveguide, and the optical waveguide and the surface optical element A transparent resin is filled in between.

  Another aspect of the present invention is an interface module having an optical transmission line including an interposer having a signal processing LSI mounted thereon and having an electrical terminal for connecting a mounting board, and an optical waveguide for externally wiring a high-speed signal. And an interface module-attached LSI package including an electrical connection terminal for electrically and mechanically connecting the interposer and the interface module, wherein the interface module has an optical input / output end of an optical waveguide from an element mounting surface. A ferrule that holds and positions the optical waveguide so as to protrude, an electrical wiring provided on at least an element mounting surface of the ferrule, and a surface mounted on the element mounting surface of the ferrule and electrically connected to the electrical wiring A photoelectric conversion header having a type optical element, and the optical waveguide The light input / output end protruding from the element mounting surface of the ferrule has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the element mounting surface of the ferrule is relative to the optical waveguide direction of the optical waveguide It is characterized in that the surface is shifted by 2 degrees or more from the vertical surface.

  Another aspect of the present invention is an interface module having an optical transmission line including an interposer having a signal processing LSI mounted thereon and having an electrical terminal for connecting a mounting board, and an optical waveguide for externally wiring a high-speed signal. And an interface module-attached LSI package comprising an electrical connection terminal for electrically and mechanically connecting the interposer and the interface module, wherein the interface module is a planar light emitting element or a planar light receiving element. A photoelectric conversion header having an optical element, an optical waveguide that guides light, a ferrule that holds and positions the optical waveguide, and an electrical wiring provided on the ferrule, wherein the electrical wiring is the ferrule The ferrule from the surface where the optical input / output end of the optical waveguide held by the ferrule is exposed. The planar optical element is mounted on a surface of the ferrule on which the optical input / output end of the optical waveguide is exposed and is electrically connected to the electrical wiring. The light input / output end exposed on the surface optical element mounting surface of the ferrule of the optical waveguide has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the ferrule of the ferrule has The surface on which the light input / output end of the optical waveguide to be held is exposed is a surface shifted by 2 degrees or more from the direction perpendicular to the optical waveguide direction of the optical waveguide, and the optical waveguide and the planar optical element It is characterized by being filled with a transparent resin.

  Another aspect of the present invention is a method of manufacturing a photoelectric conversion header, which holds and positions an optical waveguide that guides light and has a surface on which an optical input / output end of the optical waveguide is exposed. A surface type light emission on the inclined surface with respect to a ferrule which is an inclined surface deviated from a plane perpendicular to the optical waveguide direction of the optical waveguide and in which an electrical wiring is formed extending from the inclined surface to at least one other side surface. A step of mounting a surface type optical element comprising an element or a surface type light receiving element, electrically connecting the surface type optical element and the electrical wiring, and a back surface opposite to the surface of the surface type optical element to which the electrical wiring is connected A step of disposing a stopper member having a surface substantially parallel to the back surface, and inserting the optical waveguide into the ferrule and the surface light in a state where the stopper member is disposed on the back surface of the surface optical element. Transparent resin between element and optical waveguide Characterized in that it comprises a, and performing Hama.

  Another aspect of the present invention is an optical waveguide, a ferrule that holds and positions the optical waveguide so that the light input end of the optical waveguide protrudes at least partially from the element mounting surface, and the ferrule. An optical wiring provided on at least the element mounting surface, and a planar optical element mounted on the element mounting surface of the ferrule and electrically connected to the electric wiring, and the optical input / output end of the optical waveguide Has an end face that is substantially perpendicular to the optical waveguide direction of the optical waveguide, and the element mounting surface of the ferrule is a surface that is offset by 2 degrees or more from the plane perpendicular to the optical waveguide direction of the optical waveguide. And an optical wiring system using a photoelectric conversion header in which a transparent resin is filled between the optical waveguide and the planar optical element, wherein the planar optical element is a light emitting element. (Optical transmission header) and the surface A second photoelectric conversion header (optical reception header) whose optical element is a light receiving element is optically coupled by the optical waveguide, and transmits an optical signal from the first photoelectric conversion header to the second photoelectric conversion header. It is characterized by.

  INDUSTRIAL APPLICABILITY According to the LSI package with photoelectric conversion header and interface module and the manufacturing method LSI for photoelectric conversion header of the present invention, high-speed wiring between LSI chips can be realized at low cost, which greatly contributes to advancement of information communication equipment and the like. Can do.

  Before describing an embodiment of the present invention, an LSI package with an interface module previously proposed by the present inventors (Japanese Patent Application No. 2003-39828) will be described with reference to FIG. In FIG. 13, 21 is an interposer substrate, 22 is a solder ball, 23 is a signal processing LSI, 24 is an electrical connection terminal, 25 is a wiring board, 27 is an optical element driving IC, 28 is a photoelectric conversion unit, 5 is an optical fiber, 31 Is a heat sink, and 32 is a cooling fan.

  The high-speed signal from the signal processing LSI 23 is not supplied to the mounting board through the solder balls 22 but is supplied to the optical element driving IC 27 through the electrical connection terminals 24 and the wiring board 25. Then, the optical signal is converted into an optical signal by the photoelectric conversion unit 28 and given to the optical fiber 5. In this package, an interface module (a portion in which the wiring substrate 25, the optical element driving IC 27, the photoelectric conversion unit 28, and the optical fiber 5 are combined) can be mounted later on the interposer substrate 21 on which the signal processing LSI 23 is mounted. Further, a heat sink 31 and a cooling fan 32 are mounted thereon, so that the signal processing LSI 23 can dissipate heat.

  The LSI package with an interface module configured in this way is in exactly the same procedure and conditions as those for mounting an LSI on a mounting board manufactured on an existing production line using an existing mounting device (such as a reflow device). Can be mounted on the board. That is, the interposer substrate 21 on which the signal processing LSI 23 is first mounted is mounted on a board together with other electronic components using an existing method, and then the interface module is covered from above and fixed (for example, fixed with screws or an adhesive). Then, the structure of FIG. 13 can be configured on the mounting board.

  At this time, the process up to the board mounting of the interposer substrate 21 can be produced without changing any existing mass production line, and the only work specific for constructing the optical wiring board is the work of mounting the interface module. In addition, the process of fixing the interface module by covering it from above does not require any special high-precision positioning (for example ± 10 μm), but it is sufficient if the accuracy of a general electrical connector is sufficient, and the mounting process It does not increase the cost. In other words, using an existing inexpensive mounting board (for example, a glass epoxy substrate) and an existing mounting method, a high-speed board having high-speed wiring (for example, 20 Gbps per wiring) that is generally difficult to achieve with board electrical wiring is realized. It becomes possible.

  The LSI package with an interface module in this form is an electrical mounting body except for the photoelectric conversion unit 28 and the optical fiber 5 (hereinafter, 28 and 5 are collectively referred to as a photoelectric conversion header). Is easy to apply and cost reduction by mass production is easy. That is, if the cost required for the photoelectric conversion header (optical element subassembly) can be reduced, the cost of the high-speed wiring board using light can be reduced, which greatly contributes to the increase in capacity and advancement of information communication equipment. it can. The present invention provides a technique capable of reducing the cost of the photoelectric conversion header of such an LSI package with an interface module.

  The conventional example of the above-described photoelectric conversion header has already been described, but the part that increases the cost among them is an assembly failure of the photoelectric conversion header, especially when an optical waveguide such as an optical fiber is mounted and fixed. Such as a defect that mechanically breaks the optical element by the body and a characteristic defect that operatively generates return light noise, and the manufacturing cost of the defective product is added to the product cost of the non-defective product, the cost increases. Further, as described above, when the optical fiber is subjected to oblique polishing or the like, a larger processing cost is added to the manufacturing cost.

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

(First embodiment)
FIG. 1 is a cross-sectional view showing a schematic configuration of a photoelectric conversion header according to the first embodiment of the present invention.

  In FIG. 1, reference numeral 1 is a ferrule for holding and positioning an optical waveguide for guiding light (for example, an optical fiber or an optical waveguide film, which will be described below as an example), and 2 is a ferrule. Electrical wiring (leading electrode) patterned on 1, 3 is a surface light emitting device (for example, VCSEL: Vertical Cavity Surface Emitting Laser), 4 is an optical device mounting bump, 5 is an optical fiber (5a: core, 5b: clad) and 6 are transparent resins as adhesives for the optical element underfill material and optical fiber.

  For example, the ferrule 1 is formed by resin molding using a mold with an epoxy resin mixed with about 80% of a glass filler of about 30 μm. The ferrule 1 is subjected to pattern metallization using a metal mask and sputtering to form the electric wiring 2. Accordingly, it is possible to mass-produce the ferrule 1 with electrical wiring at a very low cost while having very high accuracy of 1 μm or less. Here, the electrical wiring 2 is formed from the element mounting surface of the ferrule 1 to one side surface of the ferrule 1.

  As a material of the ferrule 1, in addition to the above epoxy resin, a resin in which a glass filler is mixed with PPS (polyphenylene sulfide), LCP (liquid crystal polymer), polyamide resin, silicone resin, acrylic resin, or polycarbonate resin can also be used. The optical element mounting bumps 4 may be made of various materials and connection methods such as solder bumps (heat melting), Au bumps (thermocompression bonding), Sn / Cu bumps (solid phase bonding). As the optical fiber 5, for example, a quartz-based multimode GI (Graded Index) fiber (core diameter 50 μm, cladding diameter 125 μm, NA = 0.21) is used. The optical fiber 5 can also be a multicomponent glass-based optical fiber or a plastic optical fiber.

  Here, the end face of the optical fiber 5 is a plane substantially perpendicular to the optical waveguide direction of the optical fiber 5, and in the case of a quartz fiber or the like, a stress fracture surface by slightly scratching with a diamond blade and applying a side pressure, A so-called cleave surface may be used. A dedicated cutter is commercially available for this end surface cleave, and can be cleaved simultaneously with an optical fiber array (ribbon fiber). In the case of a plastic fiber or the like, an end face forming method such as vertical cutting with a knife or hot plate shaping may be used. Of course, when the cost is commensurate, these may be performed by polishing.

  The optical element mounting surface of the ferrule 1 is a surface shifted from a surface perpendicular to the optical waveguide direction of the optical fiber 5. The inclination angle of the optical element mounting surface may be set to an angle at which the optical fiber does not contact the active part of the light emitting element. Hereinafter, an example of setting the inclination angle of the optical element mounting surface will be shown.

  In silica-based optical fibers for optical communications, ribbon fibers generally use an array arrangement with a pitch of 250 μm. In many cases, the light-emitting element is designed with a pitch of 250 μm so that the light-emitting element can be adapted to the light-emitting element.

On the other hand, VCSELs are generally used as high-speed surface light-emitting elements. The VCSEL generally refers to a vertical cavity surface emitting laser, but normally, it often refers to a vertical DBR (Distributed Bragg Reflector) type surface emitting laser. In VCSELs with an oscillation wavelength band of 850 nm, which has become relatively versatile, Al _x Ga _1-x As is used as a DBR mirror, and a reflectivity of 99.9% or more required from oscillation conditions is obtained. For this purpose, for example, a layer pair of λ / 4 thickness of Al _0.1 Ga _0.9 As / Al _0.9 Ga _0.1 As is repeatedly laminated to have a thickness of about 3.5 μm. Since this is necessary for each of the p side and the n side across the active layer, the total thickness is 7 to 8 μm.

As a current confinement (oscillation region restriction) structure of a VCSEL, a selective oxidation structure is often used in a high-speed VCSEL. In the selective oxidation structure, a highly oxidizable crystal (for example, Al _0.98 Ga _0.02 As) is thinly provided in the vicinity of the laser active layer, and water vapor oxidation is selectively performed from the outside leaving a desired laser active region. It is a structure to make. As an example, a crystalline layer such as a first DBR layer, an active layer, a selective oxidation layer, and a second DBR layer are sequentially stacked, mesa etching with a diameter of 30 μm is performed, and selective oxidation is performed from the side surface by 10 μm, so that the current injection opening diameter is A 10 μm selective oxidized VCSEL can be made. At this time, the depth of the mesa etching only needs to reach the selective oxide layer, and the DBR thickness is not less than 3.5 μm, that is, a depth of about 4 μm.

  In consideration of this, in a 250 μm × 250 μm VCSEL chip, when the distance from the chip side to the center is 125 μm and the center of the light emitting part is set at the element center, a mesa having a height of 4 μm from the center to 15 μm is formed. The straight line extending from the side to the mesa edge has an inclination of about 2 degrees with respect to the chip surface (4 μm / 110 μm to tan 2 °, the distance from the chip side to the mesa edge is 110 μm).

  These relationships are shown together in FIG. In FIG. 2, 301 is a VCSEL substrate (for example, GaAs), 302 is a current injection opening (non-selective oxidation region), that is, the active region of the VCSEL, and 303 is a circular mesa (second DBR layer, formed deeper than the selective oxidation layer). .

  In FIG. 2, the line drawn from the upper left portion of 301 to the upper left portion of 303 represents the surface of the virtual planar contact object, and as described above, the contact angle is about 2 °. From the VCSEL side, if the optical fiber 5 or the like is not in contact with the circular mesa 303 containing the active region, the element is destroyed even if there is some contact on the substrate surface (mesa etching surface or the like). There are few things. Therefore, in FIG. 2, if the contact angle of the planar contact object is 2 ° or more, the planar contact object first contacts the substrate 301, and the VCSEL active region 302 (and the circular mesa 303) is protected. .

  Therefore, in a VCSEL with a size of 250 μm × 250 μm, which corresponds to a general ribbon fiber array pitch, the active part (diameter 30 μm mesa) does not contact the surface inclined more than 2 degrees, that is, the active part is automatically protected. Can be done. For this reason, it is desirable that the surface light emitting element mounting surface of the ferrule 1 be inclined at least 2 degrees from the surface perpendicular to the optical waveguide direction of the optical fiber 5.

  However, this inclination angle is for a plane larger than a chip having a size of 250 μm, and when an optical fiber having a diameter smaller than 250 μm is opposed, it is necessary to incline at a larger angle. For example, a typical silica-based optical fiber has a large diameter of 125 μm. In order to protect the active part of the VCSEL by aligning the center of the VCSEL with the 125 μm diameter optical fiber, an inclination of about 5 degrees is required (4 μm / 47.5 μm to tan 5 °, from the fiber end to the mesa edge. The distance is 47.5 μm).

  These relationships are summarized in FIG. In FIG. 3, 301 is a VCSEL substrate (for example, GaAs), 302 is a current injection opening (non-selective oxidation region), that is, an active region of the VCSEL, and 303 is a circular mesa (second DBR layer, formed deeper than the selective oxidation layer). The magnitude relationship is the same as in FIG. An optical fiber 5 has a diameter of 125 μm as described above. Here, it is assumed that the end face of the optical fiber 5 is cut vertically, and the center (center of the optical axis) is located on the center of the VCSEL active region. In this state, when the condition for the optical fiber to contact the surface of the substrate 301 and the corner of the circular mesa 303 is obtained, the relationship shown in FIG. 3 is obtained, and the mutual contact angle is less than 5 °.

  Therefore, in FIG. 3, if the inclination of the optical fiber is 5 ° or more as described above, the optical fiber comes into contact with the substrate 301 first, and the VCSEL active region 302 and the circular mesa 303 are protected. Further, this relationship does not hold if the center positions of the optical fiber and the VCSEL are shifted. However, as can be seen from FIG. 1, this results in an alignment problem when the VCSEL 3 is mounted on the ferrule 1. As this alignment accuracy, an accuracy of ± 5 μm or less can be ensured by a method of performing image recognition of the optical fiber holding hole. Considering this alignment accuracy further, if the optical fiber tilt angle, that is, the optical element mounting surface tilt angle of the ferrule 1 is set to 5.5 °, the optical fiber does not contact the VCSEL active part.

  Thus, in consideration of the unevenness of the VCSEL surface and the like, the optical fiber mounting surface of the ferrule is inclined so that the optical fiber does not contact the active portion of the light emitting element. Of course, in this embodiment, the thickness of the bump metal or the like on which the optical element is mounted is substantially constant in the plane, and the relative angle between the optical fiber and the VCSEL does not change even if the temperature changes.

  Further, as is well known, since the optical fiber and the light emitting element are tilted and optically coupled, it has an effect of suppressing the generation of noise due to the return light. However, in the present invention, since the distance from the light output element (VCSEL) light output surface to the optical fiber light input end surface can be extremely shortened to about 2 μm, the end surface of the optical fiber is in spite of the inclination of the optical fiber and the VCSEL. In some cases, the reflected light couples with the optical resonance mode of the VCSEL to generate return optical noise.

  In order to suppress this problem, it is only necessary to keep the near-end reflected light (reflection distance several μm) from the end face of the optical fiber 5 low. The difference in refractive index of about 1) should be made as small as possible. For this purpose, it is effective to fill the gap between the optical fiber and the optical element (VCSEL) with a transparent material having a refractive index close to that of the optical fiber. The same effect can be obtained as in the case of being away from the light emitting element. The filling of the transparent resin 6 in FIG. 1 also serves to provide this effect. Therefore, it is desirable that the transparent resin 6 has a refractive index equal to or approximately equal to the equivalent refractive index of the optical fiber.

  In addition, filling the transparent resin 6 has an effect of suppressing the optical fiber 5 from being vibrated slightly by an external force. The optical fiber 5 is in contact with various objects outside the photoelectric conversion header and can be a medium for transmitting the external force from the inside, but the optical fiber is subjected to external periodic vibration, and the vibration is When the frequency is in the vicinity of the mechanical resonance frequency, the tip of the optical fiber or the optical semiconductor element in contact therewith may cause an internal resonance vibration that slightly vibrates. The filling of the transparent resin 6 described above is effective for preventing and damping such internal vibration.

  Further, the transparent resin 6 also has an effect of buffering the difference in thermal expansion characteristics between the optical semiconductor element 3 and the ferrule 1, and stress and strain due to the difference in thermal expansion coefficient between each other can be reduced. There is an effect that the optical semiconductor element 3 and the entire optical element mounting surface opposite to the optical semiconductor element 3 are dispersed without being concentrated on the periphery of the optical element mounting bump 4. For this reason, the filling of the transparent resin 6 is also effective for preventing deterioration of the thermal cycle and the like, and in order to further enhance the effect, the transparent resin 5 has a transparent fine particle filler (for example, an average particle diameter of several μm to several tens of μm). It is also effective to mix silica and pulverized quartz. That is, by adjusting the mixing ratio of the transparent fine particle filler so that the average or equivalent thermal expansion characteristic of the resin is matched with the optical fiber or the optical semiconductor element, or an intermediate value thereof, thermal stress (thermal strain) The relaxation effect can be enhanced.

  FIG. 4 is a cross-sectional view showing a schematic configuration of the photoelectric conversion header according to the first embodiment of the present invention, and shows an embodiment of a light receiving element facing the light emitting element shown in FIG.

  In FIG. 4, 1 is a ferrule for holding and positioning an optical waveguide (for example, an optical fiber or an optical waveguide film, which will be described below as an example), and 2 is a pattern formed on the ferrule 1. Electrical wiring (extraction electrode), 3 is a surface light receiving element (PIN-PD: PIN Photo Diode, etc.), 4 is an optical element mounting bump, 5 is an optical fiber, 6 is an optical element underfill material, and an optical fiber adhesive As a transparent resin.

  The ferrule 1 can be manufactured with an epoxy resin as described above, and other materials other than the epoxy resin can be used. Furthermore, the optical element mounting bumps 4 and the optical fiber 5 may be those described above. The end face of the optical fiber 5 is substantially perpendicular to the optical waveguide direction of the optical fiber 5 as in the case of FIG. 1, and the formation method is as described above.

  The optical element mounting surface of the ferrule 1 is a surface shifted from a surface perpendicular to the optical waveguide direction of the optical fiber 5. In general, the light receiving element often has a planar structure, that is, a structure having a flat surface, and the inclination angle of the optical fiber is arbitrary as long as it is larger than the range of verticality variation of the optical fiber end face. However, the ferrule 1 used for the light emitting element of FIG. 1 can be used as it is, and the inclination angle of the optical element mounting surface is 2 ° or more (when the optical fiber is in close proximity, the setting is 5 ° or more). Then, the ferrule 1 of the light emitting element and the light receiving element can be shared.

  Also, in order to suppress reflection on the light receiving side (optical fiber end face, light receiving element surface), it is effective to fill a gap between the optical fiber and the light receiving element (PIN-PD) with a transparent material having a refractive index close to that of the optical fiber. . This suppresses reflection according to the difference in refractive index between the optical fiber and the outside at the output end of the optical fiber, and the transparent resin 6 has a refractive index equal to or substantially equal to the equivalent refractive index of the optical fiber. It is desirable.

  Filling the transparent resin 6 also has the effect of suppressing the slight vibration of the optical fiber 5 due to an external force as described above, and is effective in preventing and damping the above-described internal vibration. Further, the transparent resin 6 has an effect of buffering the difference in thermal expansion characteristics between the optical semiconductor element 3 and the ferrule 1 and is effective in preventing deterioration of the thermal cycle and the like as described above. In order to further enhance this effect, it is also effective to mix the transparent resin 5 with a transparent fine particle filler (for example, silica having an average particle diameter of several μm to several tens of μm or the like).

  The active region is a light emitting portion that emits light by current injection when the surface optical device is a light emitting device and a region surrounding the light emitting portion. Generally, the active region is a region expanded from the light emitting portion to the periphery by 10 to 20 μm, or light emission. In the case of a light receiving element, a mesa region processed so as to separate the portion from the surroundings is a region (light receiving portion) where the depletion layer extends from the pn junction or metal semiconductor junction for applying an electric field to the light receiving layer and the surrounding area Generally, it means a region enlarged by 10 to 20 μm from the light receiving portion to the periphery, or a mesa region processed so as to separate the light receiving portion from the surroundings.

  Such application of the present invention to the light receiving element can extremely shorten the distance between the optical fiber and the light receiving element, and can minimize the spread of the light beam after being emitted from the optical fiber. That is, the light receiving diameter of the light receiving element is set slightly larger than the core diameter of the optical fiber. For example, 10 μm is added to the core diameter of the optical fiber (in the case of a 50 μmΦ core optical fiber, the optical coupling efficiency is reduced). It is also effective in suppressing modal noise in multimode optical fiber transmission.

  The above-described light-emitting element mounting (FIG. 1) photoelectric conversion header (light transmission side) and light-receiving element mounting (FIG. 4) photoelectric conversion header (light reception side) reduce the cost of the optical interface module and suppress return optical noise, respectively. Although effective, in the case of an optical wiring having a relatively short distance (for example, a wiring length of 1 m or less), not only the light guided through the optical waveguide core (5a in FIG. 1) but also the optical waveguide cladding (in FIG. 1). Non-guided light (clad mode) propagating through 5b), that is, light that has an unreliable and easily fluctuating light arrival amount that is not determined by the optical coupling efficiency to the optical waveguide core 5a is easily transmitted. The combined use of the mounting (FIG. 1) photoelectric conversion header (optical transmission side) and the light receiving element mounting (FIG. 4) photoelectric conversion header (optical reception side) is effective in suppressing return optical noise.

  In other words, suppressing the reflected light on the light transmission side makes it easy for light with a large angle that becomes the cladding mode to be introduced into the optical waveguide, and if the reflection suppression is not performed on the light receiving side, the random reflected light by the cladding mode returns. Although there is a problem that the operation of the VCSEL cannot be stabilized, as described above, the light-emitting element mounted according to the present invention (FIG. 1) the photoelectric conversion header (light transmission side) and the light-receiving element mounted (FIG. 4) photoelectric conversion header (light reception side). In combination, the system can be stably operated even in an optical wiring system having a relatively short distance (for example, a wiring length of 1 m or less).

  In this case, the optical waveguide 5 is a single optical waveguide, and a light emitting element is mounted on each end (FIG. 1). A photoelectric conversion header (light transmission side) and a light receiving element are mounted (FIG. 4). Photoelectric conversion header (light reception side) Even in the form provided with the optical connector (FIG. 1), the optical connector (FIG. 1) and the optical connector (FIG. 4) separately provided with the photoelectric conversion header (optical transmission side) and the light receiving element mounting (FIG. 4) are provided. (Not shown) may be optically coupled.

  In addition, what is necessary is just to set the following as an optical fiber inclination angle of this embodiment mentioned above, ie, the maximum angle of the optical element mounting surface inclination angle of the ferrule 1. FIG.

  For example, the maximum light receiving angle of the optical fiber 5 is set as the upper limit for setting the optical fiber tilt angle. That is, at an angle larger than this, the maximum waveguide mode angle of the optical fiber is exceeded, and light in the principal axis (normal) direction of the VCSEL cannot be coupled. Therefore, at an angle larger than this, the optical coupling efficiency is lowered more than necessary, so that the total profit / loss is increased. An example of the maximum light receiving angle of the optical fiber 5 is the above-described quartz-based multimode GI (Graded Index) fiber (core diameter 50 μm, cladding diameter 125 μm, NA = 0.21), and about 12 ° (half-angle value). is there.

  Here, the half angle is half of the light reception full angle of the optical fiber (the angle obtained by adding all the positive and negative components of the angle deviation from the main axis direction), and represents the maximum allowable angle deviation value from the main axis direction. The optical fiber 5 may be a multi-component glass-based optical fiber or a plastic optical fiber. In that case, the optical fiber 5 may have a larger light receiving angle (NA).

  Next, as an optical coupling limit between the optical fiber and the VCSEL, there is a combination angle of the maximum light receiving angle of the optical fiber and the light emission angle of the VCSEL. This is because light at the angle of the main axis direction of the VCSEL cannot be coupled at an angle larger than the maximum light receiving angle of the optical fiber, but the light at the skirt portion due to the angular spread of the VCSEL output light can be coupled. The lost angle becomes the physical limit of the optical coupling itself. For example, the output light emission angle of a VCSEL is about 8 ° (full width at half maximum: FWHM) in single mode oscillation and about 20 ° at maximum (full width at half maximum: FWHM) in high-order transverse mode oscillation.

  Therefore, a value obtained by adding each half angle to the maximum light receiving angle of the optical fiber is a substantial limit of optical coupling, and this is the optical fiber inclination angle of the above-described embodiment of the present invention, that is, the optical element mounting surface inclination angle of the ferrule 1. Should be the maximum angle. In the case of the above optical fiber, the maximum setting angle is 16 ° for the single mode oscillation VCSEL (the total of the optical fiber maximum receiving angle 12 ° and the half-value of the VCSEL output light half angle 4 °), and 22 ° for the high-order transverse mode oscillation VCSEL (optical fiber). A maximum light receiving angle of 12 ° and a VCSEL output light half-value half-angle of 10 °), and setting an angle larger than this makes little sense.

  As described above, in the photoelectric conversion header of this embodiment, the ferrule 1 holding the optical waveguide 5 such as an optical fiber and the optical elements 3 and 7 are mounted by the bumps 4 having substantially the same height. On the other hand, the tilt angle fluctuation of the optical elements 3 and 7 hardly occurs. In addition, since the mounting surface is configured to have a normal line that is shifted from the optical axis direction of the optical waveguide 5, a gap corresponding to the cross-sectional width and the shift angle of the optical waveguide 5 is automatically formed. The problem that the active part contacts and breaks the optical waveguide 5 can be essentially prevented. For this reason, it can be set so that the optical element active portion is not damaged even if the optical waveguide 5 is brought close to the optical elements 3 and 7 or until the optical waveguide 5 is in contact with the optical elements 3 and 7. It is possible to bring the optical waveguide 5 and the optical element active part close to each other with good reproducibility up to several μm. Therefore, even if the light receiving diameter of the light receiving element 7 is reduced to the optical waveguide core diameter to increase the speed, high-efficiency optical coupling can be performed without using an additive such as a lens that increases the cost.

  Further, since the optical elements 3 and 7 and the optical waveguide 5 are inclined with respect to each other, it is of course possible to suppress return light noise. In particular, the transparent resin 6 that suppresses reflection at the interface of the optical waveguide is used. In order to perform filling, even if the optical elements 3 and 7 and the optical waveguide 5 are brought close to several μm, the distance effect exceeds the tilt effect and the generation of return optical noise is suppressed. Further, the optical input / output end of the optical waveguide 5 (such as an optical fiber or an optical waveguide film) for exhibiting the above effect may be a vertical end face, and there is no need to perform an oblique process such as an oblique polishing process with a high process cost. . Further, since the vertical end face is filled with the transparent resin 6, no extreme surface accuracy is required at the light input / output end of the optical waveguide 5, and a so-called cleave end face can be applied. Therefore, this embodiment has an advantage that there is almost no cost bottleneck in terms of processing cost. For these reasons, high-speed LSI chip wiring can be realized at low cost, which can greatly contribute to the advancement of information communication equipment and the like.

(Second Embodiment)
5 and 6 are a cross-sectional view and a top view showing a schematic configuration of an optical element mounted with a photoelectric conversion header according to the second embodiment of the present invention. FIG. 5 shows a case where a light-emitting element is used as the optical element. FIG. 4 shows a configuration example in the case of a light receiving element. The optical element structure itself may be a mesa structure like the VCSEL described above, but here, a low electrode capacitance type element intended for high-speed operation is shown as an example.

  In FIG. 5, 301 is a semiconductor substrate, 302 is a laser oscillation region, 303 is a circular mesa, 304 is an insulating film, 305 is an active region electrode, and 306 is a ground electrode. In FIG. 6, 701 is a semiconductor substrate, 702 is an inverted impurity diffusion region (light receiving portion pn junction), 703 is a circular mesa, 704 is an insulating film, 705 is an active region electrode, and 706 is a ground electrode. (B) on the right side of each figure is a top view of the element, and (a) on the left side of each figure is a cross-sectional view of the A-A 'portion and B-B' portion of each top view. The broken line in each figure indicates the facing position of the optical fiber 5. The insulating films 304 and 704 are thick film insulators that reduce the parasitic capacitance of the electrodes for high-speed operation of the element. For example, a polyimide film with a film thickness of 4 μm is used. This thickness corresponds to the aforementioned mesa etching depth of the VCSEL and corresponds to backfilling the mesa etching region for selective oxidation.

  In addition, when the light receiving element (PIN-PD) is arrayed, minority carriers (holes when the non-diffusion region is n-type) are diffused by the carrier concentration gradient to prevent the minority carriers from reaching the adjacent elements. Mesa etching is performed as a diffusion preventing groove. In the case of a PIN structure using a direct transition type semiconductor material, the depth of the impurity diffusion region is often about 1 μm, the thickness of the light absorption layer is often 2 to 3 μm, and the depth of the minority carrier diffusion preventing groove is about 4 μm. What is necessary is just to form in depth. A thick film insulator is provided in order to reduce the capacitance of the electrode by filling back the mesa etching region in the minority carrier diffusion preventing groove portion like the VCSEL.

  Here, only the active part electrodes 305 and 705 need to reduce the electrode capacity by using a thick film insulator, but all the bumps have the same structure and size for the purpose of the present invention. It is desirable that the ground electrodes 306 and 706 have the same configuration as the active portion electrode. Accordingly, the entire element has a substantially flat surface, and the function differs depending on whether the wiring pattern is connected to the active part or connected to the substrate (not shown) through a thick film insulator. The mechanical configuration as the electrode pad is the same.

  At this time, the points 305 to 306 (or 705 to 706) are formed except for the inclination direction of the optical element mounting surface of the ferrule 1 shown in FIG. It is desirable not to form the electrode and its wiring in the direction in which the element is inclined. The reason for this will be described with reference to FIG.

  7 is a schematic configuration diagram of an example equivalent to the photoelectric conversion header shown in FIG. 1, and shows an example in which the 4-channel array element of the light emitting element shown in FIG. 5 is mounted as an optical element. 7B is a side view seen from the optical element mounting surface of the ferrule 1, and FIG. 7A is a cross-sectional view of the side view C-C '. The light emitting element 3 corresponds to being mounted in a state where the element is turned upside down in the top view of FIG. 5, and in the side view on the right side of FIG.

  As can be seen from FIG. 7, in this embodiment, the light emitting element 3 is inclined in the vertical direction of the right side of FIG. 7, and in the vertical end face optical fiber, the vertical direction of the light emitting element 3 (in this case, CC ′ The edge of the optical fiber comes into contact with the intersection of the indicator line and the optical fiber edge circle, above the active region. As a matter of course, in this part, the bonding wire or the like provided there is deformed due to mechanical contact when the optical fiber and the light emitting element are in contact with each other, and in an extreme case, it is cut. For this reason, it should be avoided to place a three-dimensional structure in this part, but even thin flat electrodes such as vapor deposition electrodes can be damaged by being scratched by an optical fiber or gradually deteriorated by mechanical stress. It is desirable not to arrange it because of the possibility of disconnection. For this reason, in the optical elements of FIGS. 5 and 6, the electrodes are arranged in the diagonal direction of the element, and the arrangement in the vertical direction is avoided.

(Third embodiment)
FIG. 8 is a sectional view showing a schematic configuration of a photoelectric conversion header according to the third embodiment of the present invention. In addition, the same code | symbol is attached | subjected to FIG. 1 and an identical part, and the detailed description is abbreviate | omitted.

  In the present embodiment, a light absorbing resin 8 is provided in addition to the configuration of FIG. The light absorbing resin 8 is, for example, an epoxy resin, an acrylic resin, a silicone resin, or the like mixed with carbon fine particles, a pigment material, germanium fine particles, and the like, and is formed by resin molding or the like as shown in FIG. At this time, the light-absorbing resin 8 is provided in a thickness that is sufficiently opaque with respect to the wavelength used (for example, a wavelength of 850 nm, 0.5 mm in the case of a resin containing 20% Ge fine particles), Although it is desirable to form the cover, there may be a part that is not partially covered (for example, an electrode extraction part). The function of the light absorbing resin 8 relates to the suppression of the return light noise described above.

  The transparent resin 6 filled for suppressing the return light noise has an effect of suppressing the reflection of the end face of the optical fiber, but since a perfect refractive index match cannot always be realized, a slight residual reflection often remains. When the medium is air, the light due to the residual reflection is often scattered and diffused to the surroundings. In this case, since the transparent resin 6 has a higher refractive index than the surrounding air, the light is reflected at the outer peripheral air interface. A considerable amount of light is reflected inside. That is, there is a problem that the transparent resin 6 becomes a light confining substance and hinders the rapid dissipation of residual reflected light, that is, unnecessary light. As a result, the residual reflected light is confined to return light to the VCSEL, which increases the background noise level of the VCSEL. This increase in noise causes an increase in jitter and the like when performing very high-speed optical transmission, and is not so preferable. Further, in the photoelectric conversion header on the light receiving side, the portion where the reflected light on the surface of the light receiving element should be quickly dissipated is confined by the transparent resin 6 and reaches the light emitting element side as backflow light to the optical fiber.

  In order to solve the light confinement problem in the configuration in which the transparent resin 6 is filled, the light-absorbing resin 8 is provided in a portion corresponding to the air interface of the transparent resin 6 in the embodiment of FIG. As the light absorptive resin 8, a resin having a refractive index equivalent to that of the transparent resin 6 can be used. In short, the transparent resin 6 may be mixed with a light absorbing material. In addition, even if the light-absorbing resin 8 and the transparent resin 6 do not have the same refractive index, in general, the resin material can easily realize a refractive index of about 1.4 to 1.6, resulting in a combination with a relatively small refractive index difference. easy. For this reason, in the embodiment of FIG. 8, the reflected light at the boundary of the transparent resin 6 is almost eliminated, and the light absorbing resin 8 is quickly sucked.

  In the light absorbing resin 8, the light absorber in the resin absorbs the residual reflected light and suppresses the return light to the light emitting element 3. At this time, since the light spreads to every corner in the transparent resin 6, even if there is a part from which the light absorbing resin 8 is removed, for example, about 10% of the surface of the transparent resin 6, the reflected light there is It is quickly removed at another light-absorbing resin contact portion, and there is virtually no light trapped inside. For this reason, there is no problem even if a part where the light-absorbing resin 8 is not provided is formed as described above. Such an example corresponds to a case where a light-absorbing resin is not partially provided at an electrode portion or the like as a recognition mark confirmation window at the time of mounting.

  Instead of providing the light absorbing resin 8 described above, a method of forming a second transparent resin (not shown) similar to the transparent resin 6 on the light absorbing resin 8 is also effective. This is equivalent to extending the boundary of the transparent resin 6 near the exit of the gap between the optical element and the ferrule to a farther position, and spatially diffuses the light reflected back to the resin boundary. This makes it difficult to flow back into the gap between the optical element and the ferrule. For example, there is substantially no problem if the second transparent resin is provided in a thickness greater than the length from the optical axis of the optical fiber to the end of the optical element.

  The embodiment shown in FIG. 8 can be modified as shown in FIG. In FIG. 9, 1 to 6 are exactly the same as FIG. 8, 8 is a light-absorbing resin that covers the entire photoelectric conversion header, 9 is an optical element driving IC (driver, receiver, etc.), 10 is a wiring board, and 11 is heat dissipation. A mounting substrate 12 serving also as a plate is a bonding wire.

  FIG. 9 shows an embodiment in which the photoelectric conversion header of FIG. 1 or FIG. 4 is applied to the LSI package with an interface module of FIG. 13, after the photoelectric conversion header, the optical element driving IC, etc. are mounted and electrically connected by wire bonding or the like. This is an example in which a protective mold resin is provided on the interface module portion. Needless to say, the light-absorbing resin 8 or the second transparent resin described above can be used as the protective mold resin, and the effect includes the above-described return light noise suppression effect.

(Fourth embodiment)
FIG. 10: is sectional drawing which shows schematic structure of the photoelectric conversion header concerning the 4th Embodiment of this invention. In addition, the same code | symbol is attached | subjected to the part same as FIG. 8, and the detailed description is abbreviate | omitted.

  This embodiment differs from the previous third embodiment in that the outer shape of the light-absorbing resin 8 in FIG. 8 is an extension of the ferrule 1, and the photoelectric conversion header is shaped like a rectangular parallelepiped chip. Is a point.

  With such a configuration, since the optical semiconductor element is not exposed to the outside, handling is easy, and restrictions on mounting are reduced. For example, even if the photoelectric conversion header is exposed to flux or molten solder, it is not easily affected because it does not directly contact the optical element. In addition, by suppressing the protrusion of the light-absorbing resin portion, even if the electrode lead-out portion is placed very close to the mounting substrate, it is unlikely that anything other than the electrode will hit the mounting substrate first. Therefore, in this embodiment, a flip chip type mounting method as shown in FIG. 11 can be applied.

  In FIG. 11, electrical wiring (not shown) for connecting each element is formed on 10 wiring boards. Reference numeral 13 in FIG. 11 denotes an underfill material for the flip chip mounting surface of the optical element driving IC and the photoelectric conversion header, and 4 'denotes a connection bump. By mounting in this way, the wiring from the optical element driving IC to the photoelectric conversion header can be shortened, which is effective in improving high-speed operation characteristics.

(Fifth embodiment)
12 (a) to 12 (c) are cross-sectional views illustrating the outline of the manufacturing process of the photoelectric conversion header according to the fifth embodiment of the present invention. In addition, the same code | symbol is attached | subjected to FIG. 1 and an identical part, and the detailed description is abbreviate | omitted.

  In the manufacturing process of the photoelectric conversion header of this embodiment, first, an optical element is mounted on the ferrule 1 having the electrode 2 and the inclined optical element mounting surface. This process is performed by a method of mechanically aligning the optical fiber guide hole and electrode pattern of the ferrule and the active area pattern of the optical element by image recognition, and for example, controlling the mounting position accuracy to ± 2 μm. The connection of the optical element to the electrode 2 uses, for example, thermocompression bonding of Au stud bumps.

  Next, the ferrule is set on a jig 14 with a fixed wall (stopper) having an inclination angle equivalent to the inclination angle of the optical element mounting surface of the ferrule 1 on the back surface (FIG. 12A). At this time, the ferrule 1 and the jig 14 are not fixed, and a guide groove or the like is provided in the jig 14 so that the ferrule 1 can slide only in the direction of the optical fiber guide hole on the jig 14. The material and configuration of the guide groove of the jig 14 are considered so that the friction against the ferrule 1 is reduced. For example, you may make it arrange | position a fluororesin in a contact part.

  Next, the optical fiber 5 is inserted into the ferrule 1 as shown in FIG. At this time, a transparent resin (adhesive) 6 for fixing the optical fiber may be first applied in a liquid state to reduce friction when the optical fiber is inserted. The optical fiber 5 is inserted using a device capable of monitoring the optical fiber insertion pressure, such as a micrometer with a pressure sensor. Then, the insertion of the optical fiber is stopped at the rising point when the insertion pressure reaches a predetermined pressure while the optical fiber is inserted, or the differential of the insertion pressure with respect to the insertion distance. The insertion stop pressure of the optical fiber 5 may be set to a pressure value that does not cause a crack or the like in the optical element substrate below the edge breaking pressure of the optical fiber.

  Finally, as shown in FIG. 12C, the transparent resin 6 is solidified. As the transparent resin 6, a thermosetting resin or an ultraviolet curable resin is used. When the optical fiber 5 reaches a predetermined insertion position, a curing process such as heating or ultraviolet irradiation may be performed.

  By using such a manufacturing method, it is possible to prevent excessive external force from being applied to the connection portion (bump electrode 4) between the optical element and the ferrule, and it is possible to significantly reduce optical element mounting defects (such as electrode disconnection). The portion that receives the most external force in this optical fiber insertion is the optical fiber and the optical element substrate in the vicinity of the optical fiber contact portion, and the bump electrode 4 is only subjected to the force due to the friction between the ferrule 1 and the jig 14. As described above, this can be reduced by devising the jig 14 or the like to reduce the friction between the ferrule 1 and the jig 14. By setting, the friction between the ferrule 1 and the jig 14 can be made substantially zero.

(Modification)
The present invention is not limited to the above-described embodiments. For example, although only a part of the light emitting elements is described in the embodiment, the light receiving element can be similarly implemented except for a part unique to some of the light emitting elements. In addition, the materials, shapes, arrangements, and the like shown in the embodiments are merely examples, and the embodiments can be combined and implemented. In addition, the present invention can be variously modified and implemented without departing from the spirit of the present invention.

Sectional drawing which shows schematic structure of the photoelectric conversion header (light emitting element mounting) concerning 1st Embodiment. FIG. 3 is a schematic cross-sectional view for explaining the arrangement relationship of optical elements in the first embodiment. FIG. 3 is a schematic cross-sectional view for explaining the arrangement relationship of optical elements in the first embodiment. Sectional drawing which shows schematic structure of the photoelectric conversion header (light receiving element mounting) concerning 1st Embodiment. Sectional drawing and a top view which show schematic structure of the light emitting element mounted in the photoelectric conversion header concerning 2nd Embodiment. Sectional drawing and a top view which show schematic structure of the light receiving element mounted in the photoelectric conversion header concerning 2nd Embodiment. Sectional drawing and a top view which show schematic structure of the light emitting element of the 4-channel array mounted in the photoelectric conversion header concerning 2nd Embodiment. Sectional drawing which shows schematic structure of the photoelectric conversion header concerning 3rd Embodiment. Sectional drawing which shows schematic structure of the LSI package with an interface module concerning 3rd Embodiment. Sectional drawing which shows schematic structure of the photoelectric conversion header concerning 4th Embodiment. Sectional drawing which shows schematic structure of the LSI package with an interface module concerning 4th Embodiment. Sectional drawing which shows the outline of the manufacturing process of the photoelectric conversion header concerning 5th Embodiment. Sectional drawing which shows schematic structure of LSI package with an interface module which the present inventors have already proposed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ferrule 2 ... Lead electrode 3, 7 ... Plane type optical semiconductor element 4 ... Connection bump 5 ... Optical fiber 6 ... Transparent resin 8 ... Light-absorbing resin 9 ... Optical element drive IC
10 ... Wiring board 11 ... Mounting board (heat sink)
DESCRIPTION OF SYMBOLS 12 ... Bonding wire 13 ... Underfill 14 ... Assembly jig 21 ... Interposer substrate 22 ... Solder ball 23 ... Signal processing LSI
24 ... Electric connection terminal 25 ... Wiring board 27 ... Optical element drive IC
28 ... Photoelectric conversion unit 31 ... Heat spreader 32 ... Cooling fan

Claims (17)

An optical waveguide, a ferrule that holds and positions the optical waveguide so that an optical input / output end of the optical waveguide protrudes at least partially from the element mounting surface, and an electrical circuit provided on at least the element mounting surface of the ferrule Wiring, and a planar optical element mounted on the element mounting surface of the ferrule and electrically connected to the electrical wiring,
The light input / output end protruding at least partially from the element mounting surface of the ferrule of the optical waveguide has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the element mounting surface of the ferrule is the light guide A photoelectric conversion header characterized in that the photoelectric conversion header is a surface that is shifted by 2 degrees or more from a surface perpendicular to the optical waveguide direction of the wave body.   2. The photoelectric conversion header according to claim 1, wherein the electrical wiring is formed so as to extend from an element mounting surface of the ferrule to at least one side surface of the ferrule.   The photoelectric conversion header according to claim 1 or 2, wherein a transparent resin is filled between the optical waveguide and the planar optical element. A planar optical element comprising a planar light emitting element or a planar light receiving element, an optical waveguide for guiding light, a ferrule for holding and positioning the optical waveguide, and an electrical wiring provided on the ferrule And
The electrical wiring is formed across at least one side surface of the ferrule from a surface where the light input / output end of the optical waveguide held by the ferrule of the ferrule is exposed, and the planar optical element is the ferrule of the ferrule. The optical input / output end of the optical waveguide held by the optical waveguide is mounted on the exposed surface and is electrically connected to the electrical wiring, and the optical input exposed to the surface optical element mounting surface of the ferrule of the optical waveguide. The output end has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the surface of the ferrule on which the optical input / output end of the optical waveguide held by the ferrule is exposed is the optical waveguide of the optical waveguide. A photoelectric conversion header, wherein the photoelectric conversion header is a surface deviated by 2 degrees or more from a surface perpendicular to the wave direction, and is filled with a transparent resin between the optical waveguide and the planar optical element.   5. The photoelectric conversion header according to claim 1, wherein an electrode of the planar optical element is formed so as to avoid a region in contact with the optical waveguide or a region closest to the optical waveguide. 6.   6. The photoelectric conversion header according to claim 3, wherein a refractive index of the transparent resin is set to be substantially equal to a mode refractive index (equivalent refractive index) of the optical waveguide.   The photoelectric conversion header according to claim 3, wherein the transparent resin is mixed with a transparent filler having a refractive index substantially equal to that of the transparent resin.   The photoelectric conversion header according to any one of claims 3 to 7, wherein a resin having a light absorption property is further provided in a portion where the transparent resin is exposed.   4. The transparent resin is exposed at a portion where another transparent resin is provided with a thickness greater than the length from the optical axis of the optical waveguide to the end of the surface optical element. The photoelectric conversion header according to any one of 7.   The photoelectric conversion header according to claim 8, wherein the light-absorbing resin is formed so as to maintain substantially the same surface as a side surface of the ferrule. An interposer having a signal processing LSI mounted thereon and having an electrical terminal for connecting a mounting board, an interface module having an optical transmission line made of an optical waveguide for externally routing high-speed signals, and the interposer and the interface module are electrically and An LSI package with an interface module having electrical connection terminals for mechanical connection,
The interface module includes a ferrule that holds and positions the optical waveguide so that an optical input / output end of the optical waveguide protrudes at least partially from the element mounting surface, and electrical wiring provided on at least the element mounting surface of the ferrule And a surface-type optical element mounted on the element mounting surface of the ferrule and electrically connected to the electrical wiring,
The light input / output end protruding at least partially from the element mounting surface of the ferrule of the optical waveguide has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the element mounting surface of the ferrule is the light guide An LSI package with an interface module, wherein the LSI package is a surface that is shifted by 2 degrees or more from a surface perpendicular to the optical waveguide direction of the wave body. An interposer having a signal processing LSI mounted thereon and having an electrical terminal for connecting a mounting board, an interface module having an optical transmission path made of an optical waveguide for externally routing a high-speed signal, and the interposer and the interface module electrically and An LSI package with an interface module having electrical connection terminals for mechanical connection,
The interface module is provided with a planar optical element composed of a planar light emitting element or a planar light receiving element, an optical waveguide that guides light, a ferrule that holds and positions the optical waveguide, and the ferrule. And a photoelectric conversion header having electrical wiring,
The electrical wiring is formed across at least one side surface of the ferrule from a surface where the light input / output end of the optical waveguide held by the ferrule of the ferrule is exposed, and the planar optical element is the ferrule of the ferrule. The optical input / output end of the optical waveguide held by the optical waveguide is mounted on the exposed surface and is electrically connected to the electrical wiring, and the optical input exposed to the surface optical element mounting surface of the ferrule of the optical waveguide. The output end has an end face substantially perpendicular to the optical waveguide direction of the optical waveguide, and the surface of the ferrule on which the light input / output end of the optical waveguide held by the ferrule is exposed is the optical waveguide of the optical waveguide. An LSI with an interface module, characterized in that it is a surface deviated by 2 degrees or more from a direction perpendicular to the direction, and a transparent resin is filled between the optical waveguide and the surface optical element. Package. While holding and positioning the optical waveguide that guides light, the surface from which the light input / output end of the optical waveguide is exposed is a slope that is offset from the surface perpendicular to the optical waveguide direction of the optical waveguide, A surface type optical element comprising a surface type light emitting element or a surface type light receiving element is mounted on the inclined surface with respect to a ferrule in which electrical wiring is formed across at least one other side surface from the inclined surface. And electrically connecting the electrical wiring;
Placing a stopper member having a surface substantially parallel to the back surface on the back surface opposite to the surface to which the electrical wiring of the surface optical element is connected;
A step of inserting the optical waveguide into the ferrule and filling a transparent resin between the planar optical element and the optical waveguide with the stopper member disposed on the back surface of the planar optical element;
The manufacturing method of the photoelectric conversion header characterized by including. An optical waveguide, a ferrule that holds and positions the optical waveguide so that the optical input end of the optical waveguide protrudes at least partially from the element mounting surface, and electrical wiring provided on at least the element mounting surface of the ferrule And a planar optical element mounted on the element mounting surface of the ferrule and electrically connected to the electrical wiring, and the light input / output end of the optical waveguide is in the optical waveguide direction of the optical waveguide And the element mounting surface of the ferrule is a surface that is displaced by 2 degrees or more from the surface perpendicular to the optical waveguide direction of the optical waveguide, and the optical waveguide and the surface light An optical wiring system using a photoelectric conversion header in which a transparent resin is filled between elements,
A first photoelectric conversion header (optical transmission header) in which the planar optical element is a light emitting element and a second photoelectric conversion header (optical reception header) in which the planar optical element is a light receiving element are formed by the optical waveguide. An optical wiring system that is optically coupled and transmits an optical signal from the first photoelectric conversion header to the second photoelectric conversion header. An optical waveguide, a ferrule that holds and positions the optical waveguide so that an optical input / output end of the optical waveguide protrudes at least partially from the element mounting surface, and an electrical circuit provided on at least the element mounting surface of the ferrule Wiring, and a planar optical element mounted on the element mounting surface of the ferrule and electrically connected to the electrical wiring,
The light input / output end protruding at least partially from the element mounting surface of the ferrule of the optical waveguide has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the element mounting surface of the ferrule is the light guide A photoelectric conversion header, wherein the photoelectric conversion header is a surface that is shifted by 2 degrees or more from the end face of the wave body. An optical waveguide, a ferrule that holds and positions the optical waveguide so that an optical input / output end of the optical waveguide protrudes at least partially from the element mounting surface, and an electrical circuit provided on at least the element mounting surface of the ferrule Wiring and a planar optical element mounted on the element mounting surface of the ferrule and electrically connected to the electrical wiring,
An optical input / output end projecting at least partially from the element mounting surface of the ferrule of the optical waveguide has an end surface substantially perpendicular to the optical waveguide direction of the optical waveguide, and the element mounting surface of the ferrule is the light guide A photoelectric conversion header, wherein the photoelectric conversion header is an inclined surface deviated from the end face of a wave body, and the end face of the optical waveguide does not contact an active region of the planar optical element.   The photoelectric conversion header according to claim 16, wherein a part of a peripheral edge of the end face of the optical waveguide is in contact with an inactive region of the planar optical element.

Images