JP2006173168A - Electro-optical element, method of manufacturing electro-optical element, and optical transmission module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optical element for freely changing radiation angle or light receiving diameter by forming a lens in free size. <P>SOLUTION: A recess including a substrate aperture is formed to the rear surface of the substrate on the optical path at the light emitting surface or light receiving surface of an electro-optical element formed on the front surface of substrate. Moreover, a layer including a layer aperture is also formed on the relevant optical path. An optical member is also formed in the size specified with the wall surface of the internal side of the relevant recessed part and the relevant layer aperture. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electro-optical element in which an optical member such as a lens is formed on an optical path such as a light emitting surface or a light receiving surface of the electro-optical element, and a method for manufacturing the same.

  When the electro-optic element is a surface-emitting light-emitting element, when used in an optical module or the like using the surface-emitting light-emitting element, the emission angle of light emitted from the surface-emitting light-emitting element in order to make the optical path constant There is a request to make it smaller. On the other hand, even in the case where the electro-optic element has a light receiving function such as a photodiode, there is a demand for narrowing the light receiving diameter for receiving light in order to stabilize the characteristics of the optical module.

  In mounting an electro-optic element, there is a case where it is desired to use a mounting method using a solder bump that does not use a wire, such as a flip chip bonding method. In this case, an optical function such as a light emitting function or a light receiving function of the electro-optical element is a surface opposite to the surface (hereinafter referred to as “front side”) of the semiconductor substrate on which the electro-optical element is formed (hereinafter referred to as “back side”). It is desirable to have.

  In order to solve the above two problems, Patent Document 1 forms a via hole on the back side of a semiconductor substrate on which an electro-optical element is formed, and a lens as an optical element is formed therein using a resin or the like. ing. By having this structure, the optical path length from the light emitting surface or the light receiving surface can be increased by the thickness of the substrate, which has the effect of reducing the radiation angle or the light receiving diameter, and forming a lens. The effect is further enhanced.

JP 2002-353564 A

  However, when there is a demand for further reducing the light emission angle or further reducing the light receiving diameter in order to further improve the optical characteristics of the optical module, in Patent Document 1, the shape of the lens as an optical element is a via hole. In some cases, it may not be possible to respond to the request. That is, Patent Document 1 has a problem that the degree of freedom of the shape of a lens as an optical element is small.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an electro-optic element capable of arbitrarily forming a lens size and arbitrarily changing a radiation angle or a light receiving diameter, and a method for manufacturing the same.

  In order to solve the above-described problems, an electro-optical element according to the present invention includes an electro-optical element formed on a surface and a substrate opening on a light emitting surface or a back surface on a light path of the light-receiving surface of the electro-optical element. Specified by a substrate having a recess, a layer having a layer opening on the back surface of the substrate on the optical path, and a wall surface of the layer opening formed in a convex shape inside the recess and on the back side of the substrate The gist of the present invention is to have an optical member having a size.

  According to the electro-optic element according to the present invention, the concave portion having the substrate opening is formed on the back surface of the substrate on the light path of the light-emitting surface or the light-receiving surface of the electro-optic element formed on the surface of the substrate, A layer having a layer opening is formed on the optical path. Since an optical member having a size defined by the inside of the recess and the wall surface of the layer opening is formed, the optical member according to the size of the layer opening, not the size of the substrate opening of the recess Can be formed. That is, by forming the layer opening in a desired size, an electro-optic element that can arbitrarily change the radiation angle or the light receiving diameter is obtained.

  The electro-optic element according to the present invention is the electro-optic element described above, wherein the layer opening is smaller than an area of the substrate opening and is included in the substrate opening. It is a summary.

  According to the optical functional element according to the present invention, when it is desired to make the diameter of the optical element smaller than the substrate opening, it is possible to cope with it by making the layer opening smaller than the substrate opening.

  The electro-optic element according to the present invention includes a substrate having an electro-optic element formed on a surface thereof and a recess having a substrate opening on a back surface on the light path of the light-emitting surface or the light-receiving surface of the electro-optic element; A layer formed in an annular shape around the opening of the substrate, a convex shape on the back surface side of the substrate and the inside of the recess, and formed on the layer with a size defined by the outer shape of the layer And having an optical member.

  According to the optical functional element of the present invention, the recess having the substrate opening is formed on the back surface of the substrate on the light path of the electro-optic element formed on the surface of the substrate or on the optical path of the light receiving surface. An annular layer is formed around the opening of the substrate. Since the optical member is formed on the layer in a size defined by the outer shape of the layer in a convex shape on the back side of the substrate and the back surface of the substrate, the layer is not the size of the substrate opening that the recess has. An optical member corresponding to the size defined by the outer shape of the opening can be formed. That is, by forming the outer shape of the layer opening to a desired size, an electro-optical element that can arbitrarily change the radiation angle or the light receiving diameter is obtained.

  The electro-optical element manufacturing method according to the present invention includes a layer opening formed on the light path of the light-emitting surface or the light-receiving surface of the electro-optical element on the back surface of the substrate on which the electro-optical element is formed. A layer forming step of forming a layer having a recess, a recess forming step of forming a recess on the optical path by wet etching through the layer opening, and an optical member from the mask opening to the inside of the recess. An optical member forming step of forming the optical member having a size defined by the wall surface of the layer opening in a convex shape in the concave portion and on the back surface side of the substrate by injecting a material; Is the gist.

  According to the method for manufacturing an electro-optic element according to the present invention, the electro-optic element is formed on the light path of the light-emitting surface or the light-receiving surface of the electro-optic element on the back surface of the substrate on which the electro-optic element is formed. Forming a layer having a layer opening, forming a recess on the optical path by wet etching through the layer opening in the recess forming step, and forming a recess from the mask opening by the optical element forming step. By injecting the material of the optical member into the inside of the substrate, the optical member having a size defined by the wall surface of the layer opening is formed in a convex shape inside the recess and on the back side of the substrate. An optical member corresponding to the size of the layer opening, not the size of the substrate opening, can be formed. That is, by forming the layer opening in a desired size, an electro-optic element that can arbitrarily change the radiation angle or the light receiving diameter is obtained.

  The method for manufacturing an electro-optic element according to the present invention is the method described above, wherein the layer forming step has the electro-optic element on the back surface of the substrate on which the electro-optic element is formed. A resist pattern forming step for patterning the resist so as to leave a resist in a layer opening formed on the light path of the light emitting surface or the light receiving surface; and a hard mask forming step for forming a hard mask on the entire back surface of the substrate; And a layer opening forming step of forming the layer opening by patterning the layer by peeling the layer formed on the resist together with the resist.

  According to the method for manufacturing an optical functional element according to the present invention, the resist pattern forming step is performed on the light path of the light emitting surface or the light receiving surface of the electro optical element on the back surface of the substrate on which the electro optical element is formed. The resist is patterned so that the resist is left in the layer opening, the layer is formed on the entire back surface of the substrate by the layer forming step, and the layer formed on the resist is formed together with the resist by the layer opening forming step. By peeling, a layer is patterned to form a layer opening, and in the recess forming step, a recess is formed on the optical path by wet etching through the layer opening, and the optical element forming step. By injecting the material of the optical member into the recess from the mask opening, the size is defined by the wall surface of the layer opening in a convex shape inside the recess and on the back side of the substrate Since forming the optical member having, rather than the size of the substrate aperture having a recess, it is possible to form the optical member in accordance with the size of the layer opening. That is, by forming the layer opening in a desired size, an electro-optic element that can arbitrarily change the radiation angle or the light receiving diameter is obtained.

  The electro-optical element manufacturing method according to the present invention is the above-described electro-optical element manufacturing method, wherein, in the recess forming step, the layer opening is smaller than a substrate opening included in the recess, And it makes it a summary to form so that it may be contained in the said board | substrate opening part.

  According to the method for manufacturing an optical functional device according to the present invention, when it is desired to make the diameter of the optical element smaller than the substrate opening, the layer opening can be made smaller than the substrate opening. .

  The electro-optical element manufacturing method according to the present invention includes a layer forming step of forming a layer over the entire back surface of the substrate on which the electro-optical element is formed, and the layer is processed to form the electro-optical element. Forming a layer opening on the light path of the light emitting surface or light receiving surface of the substrate, and forming a recess having the substrate opening on the optical path by etching the back surface of the substrate using the layer as a mask. A recess forming step to be formed; a layer processing step to process the layer in an annular manner so as to leave the layer in the substrate opening; and injecting the material of the optical member into the recess from the layer opening, And an optical member forming step of forming the optical member formed on the layer in a convex shape on the back side of the substrate and having a size defined by the outer shape of the layer. .

  According to the method for manufacturing an optical functional element according to the present invention, a layer is formed on the entire back surface of the substrate on which the electro-optic element is formed by the layer forming process, and the layer is processed by the layer opening forming process. Forming a layer opening on the light path of the light-emitting surface or light-receiving surface of the electro-optic element, and etching the back surface of the substrate in the recess forming step to form a recess having the substrate opening on the optical path. In the processing step, processing is performed so that a layer is left annularly around the substrate opening, and in the optical element forming step, the material of the optical member is injected into the recess from the layer opening, and the inside of the recess and the substrate Since the optical element is formed in a convex shape on the back side with a size defined by the outer shape of the layer, it is not the size of the substrate opening included in the concave portion, but the size defined by the outer shape of the layer opening. The corresponding optical member can be formedThat is, by forming the outer shape of the layer opening to a desired size, an electro-optical element that can arbitrarily change the radiation angle or the light receiving diameter is obtained.

  In addition, the present invention can be used as an optical transmission module using the electro-optic element described above.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a schematic cross-sectional view of an electro-optical element having an optical member obtained in the first embodiment. The electro-optical element in this embodiment is effective when mounting without using wires, such as flip chip bonding mounting. In that case, it is desirable to form a structure in which light is emitted from the back side of the substrate on which the electro-optic element is formed. Hereinafter, the structure of the electro-optic element will be described.
FIG. 1A shows a case where the electro-optical element 1 having a lens as the optical member 20 is a surface-emitting light emitting element as one of the light emitting elements, and FIG. The case where the element 2 is a photodiode as one of the light receiving elements is shown.

FIG. 1A will be described. The surface light emitting element 5 uses a GaAs substrate 10 as a substrate. Here, in the figure, the upper side of the GaAs substrate 10 is the back surface of the substrate, and the lower side is the front surface. A first mirror layer 11 is formed on the entire surface of the GaAs substrate 10. The first mirror layer 11 is formed as a plurality of pairs of distributed multilayer films in which p-type Al _0.9 Ga _0.1 As layers and p-type Al _0.15 Ga _0.85 As layers are alternately stacked. A GaAs well layer and an Al _0.3 Ga _0.7 As barrier layer are formed on the first mirror layer 11. On the barrier layer, the active layer 12 is formed in a quantum well structure including three well layers. A second mirror layer 13 is formed on the active layer 12. The second mirror layer 13 is formed as a plurality of pairs of distributed multilayer films in which n-type Al _0.9 Ga _0.1 As layers and n-type Al _0.15 Ga _0.85 As layers are alternately stacked. The second mirror layer is formed thinner than the first mirror layer.

  By processing the first mirror layer 11, the active layer 12, and the second mirror layer 13 by etching or the like, these three layers are formed in a columnar shape. Further, a part of the second mirror layer 13 in contact with the active layer 12 is formed from the side surface side to a part of the inner side by a processing means such as oxidation to form a current confinement layer 14. Note that the current density of the active layer 12 and the like can be controlled by controlling the formation region of the current confinement layer 14. An insulating layer 15 is formed on the side surfaces of the three layers formed in the columnar shape. The insulating layer 15 uses polyimide resin. This is because the polyimide resin is a material excellent in processing characteristics such as insulation and embedding characteristics and heat resistance.

  A cathode electrode 16 is formed on the second mirror layer 13 and the insulating layer 15. The cathode electrode 16 uses a laminated film of an alloy of Au and Ge and Au. An anode electrode 17 is formed on a part of the first mirror layer 11 where the insulating layer 15 is not formed. The anode electrode 17 uses a laminated film of an alloy of Au and Zn and Au. A recess 19 having a substrate opening 19 a is formed at a depth from the back surface side of the GaAs substrate 10 to the vicinity of the first mirror layer 11. The bottom surface portion 19b of the recess 19 is formed so as to be disposed at substantially the center of the active layer 12 where the current confinement layer 14 is not formed. This is because the light emitting surface of the surface light emitting element 5 is the active layer 12 in which the current confinement layer 14 is not formed. That is, the recess 19 is formed on the optical path from the light emitting surface. A metal layer 18 as a layer is formed on the back surface of the GaAs substrate 10. The metal layer 18 has a layer opening 18 a and is formed smaller than the substrate opening 19 a of the recess 19.

  The lens 20 as an optical member includes an in-substrate lens 20a from the concave bottom surface portion 19b to the substrate opening portion 19a, and a convex lens 20b formed so as to be in contact with the layer wall portion 18b of the layer opening portion 18a.

  In the surface-emitting light-emitting element 1 having the lens 20 described above, solder bumps can be formed on the cathode electrode 16 and the anode electrode 17 and directly mounted on a substrate to be mounted. By applying a voltage to the cathode electrode 16 and the anode electrode 17, holes and electrons are combined in the active layer 12 to emit light. The light passes through the first mirror layer 11 and is emitted to the outside through the lens 20. The lens 20 reduces the emission angle of light emitted from the active layer 12. Therefore, it is easy to align the optical axis with the light receiving element when manufacturing a device such as an optical module.

Next, FIG. 1B will be described. The photodiode 6 uses a GaAs substrate 10 as a substrate. A mirror layer 21 is formed on the entire surface of the GaAs substrate 10. The mirror layer 21 is formed as a plurality of pairs of distributed multilayer films in which p-type Al _0.9 Ga _0.1 As layers and p-type Al _0.15 Ga _0.85 As layers are alternately stacked. On the mirror layer 21, a light absorption layer 22 is formed. The light absorption layer 22 is formed of a GaAs layer into which no impurity is introduced. A contact layer 23 is formed on the light absorption layer 22. The contact layer 23 is formed of a p-type GaAs layer.

  The mirror layer 21, the light absorption layer 22, and the contact layer 23 are processed by etching or the like, so that these three layers are formed in a columnar shape. An insulating layer 24 is formed on the side surfaces of the three layers formed in the columnar shape. The insulating layer 24 uses polyimide resin. This is because the polyimide resin is a material excellent in processing characteristics such as insulation and embedding characteristics and heat resistance.

  A cathode electrode 25 is formed on the mirror layer 21 and the insulating layer 24. The cathode electrode 25 uses a laminated film of an alloy of Au and Ge and Au.

  Further, an anode electrode 26 is formed on a part of the mirror layer 21 where the insulating layer 24 is not formed. The anode electrode 26 uses a laminated film of an alloy of Au and Zn and Au.

  A recess 19 having a substrate opening 19 a is formed at a depth from the back surface side of the GaAs substrate 10 to the vicinity of the first mirror layer 11. The bottom surface portion 19 b of the recess 19 is formed so as to be disposed substantially at the center of the light absorption layer 22. This is because the light receiving surface of the photodiode 6 is the light absorption layer 22. That is, the recess 19 is formed on the optical path of the light receiving surface. A metal layer 18 as a layer is formed on the back surface of the GaAs substrate 10. The metal layer 18 has a layer opening 18 a and is formed smaller than the substrate opening 19 a of the recess 19.

  The lens 20 as an optical member is formed in the same manner as in the case of the surface-emitting light-emitting element 5 in FIG.

  The photodiode 2 having the lens 20 can also be directly mounted on a substrate to be mounted by forming solder bumps on the cathode electrode 16 and the anode electrode 17 as in the case of the surface light emitting element 1. When light is incident on the light absorption layer 22 by applying a voltage to the cathode electrode 16 and the anode electrode 17, holes and electrons are generated in the light absorption layer 22. By moving to the electrode 26 side, a photocurrent is generated. By detecting this photocurrent, the characteristics of the incident light can be grasped.

  Next, a method for manufacturing an electro-optical element having a lens as an optical member will be described. Here, the surface light emitting element 5 will be described as an example of the electro-optical element.

  FIG. 2A shows the GaAs substrate 10 on which the surface light emitting element 5 is formed. The surface light emitting element 5 has the structure described with reference to FIG.

  Next, the layer forming process will be described with reference to FIGS. 2 (b) to 3 (a). The layer forming step includes a resist pattern forming step, a hard mask forming step, and a layer opening forming step. Hereinafter, it demonstrates in order.

  FIG. 2B shows a resist pattern forming process. Photoresist 27 is applied to the entire surface of the GaAs substrate 10 on which the surface light emitting element 5 is not formed, and a photoresist pattern is formed by photolithography. The region where the photoresist 27 is left is a region where a layer opening (see FIG. 3A) is formed.

  FIG. 2C shows a hard mask forming process. In the present embodiment, the metal layer 18 is formed on the entire back surface of the GaAs substrate 10 by a vapor deposition method or a sputtering method as a hard mask. For the metal layer 18, Au, Pt, Ni, Cr, AuGe, or the like can be used. For the hard mask, an insulating film such as a silicon nitride layer or a silicon oxide layer can be used in addition to the metal layer.

  FIG. 3A shows a layer opening forming step. The layer opening 18a is formed by a lift-off method. That is, the layer such as the metal layer 18 formed on the photoresist 27 is removed by peeling the photoresist 27. The layer opening 18 a is formed on the light emitting surface of the surface light emitting element 5, that is, on the optical path emitted from the active layer 12. The opening area of the layer opening 18 a can be determined by the pattern of the photoresist 27. Accordingly, since the pattern shape and region of the photoresist 27 can be set to some extent freely depending on conditions such as a mask pattern in the resist pattern forming step, the opening region of the layer opening 18a can be set freely. .

  FIG. 3B shows a recess forming process. The recess 19 is formed by a wet etching method. The wet etching uses a chemical solution that etches the GaAs substrate 10 but does not etch the layer 18. Since wet etching etches the GaAs substrate 10 isotropically, the cross section of the recess 19 has a tapered shape as shown in FIG. That is, the opening area of the substrate opening 19a is larger than the recess bottom 19b. Since the metal layer 18 is not etched, the opening area of the substrate opening 19a can be made larger than the layer opening 18a as shown in FIG.

  In addition, when forming the recessed part 19 which has the board | substrate opening part 19a of the magnitude | size equivalent to the layer opening part 18a, it can also form by the dry etching method other than the method formed by said wet etching method.

  FIG.3 (c) shows an optical member formation process. The lens 20 as the optical member uses an ultraviolet curable resin. First, the surface of the metal layer 18 is subjected to water repellency treatment. Next, a lens precursor 30a is formed in the recess 19 by using a liquid ultraviolet curable resin by a droplet discharge method or a dispenser method. Further, an ultraviolet curable resin is injected to form the lens precursor 30 b in a convex shape with respect to the metal layer 18. At this time, the lens precursor 30b is formed in a size defined on the wall surface of the layer wall portion 18b of the layer opening 18a. Thereafter, the lens precursors 30 a and 30 b are irradiated with ultraviolet rays to cure the ultraviolet curable resin, thereby forming the lens 20. In this way, the surface light emitting element 1 having the lens 20 shown in FIG. 1A is obtained.

  Here, the ultraviolet curable resin generally has at least one of a prepolymer, an oligomer, and a monomer and a photopolymerization initiator. Among the ultraviolet curable resins, it is preferable to use an acrylic resin in consideration of the wide selectivity of viscosity. Specific examples of the ultraviolet curable acrylic resin include acrylates such as epoxy acrylates, urethane acrylates, polyester acrylates, polyate acrylates, and spiroacetal acrylates. In addition, methacrylates such as epoxy methacrylates, spiroacetal methacrylates, polyester methacrylates, and polyether methacrylates can be used.

  In addition to the ultraviolet curable resin, a polyimide resin or an acrylic resin can be used as the material of the lens 20. In this case, heat treatment or the like is performed to make the resin into the lens 20.

  In the case where the in-substrate lens 20a and the convex lens 20b are formed, they may be formed of different materials or the like in terms of the process or the optical characteristics of the lens 20.

  In order to reduce the emission angle of light emitted from the active layer 12 of the surface-emitting light-emitting element 5, it is effective to reduce the radius of curvature of the lens 20. The curvature of the lens 20 is determined by the surface tension of the ultraviolet curable resin, the wettability of the substrate, the opening area of the layer opening 18a, and the like. As described above, the opening area of the layer opening 18a can be set freely to some extent. Therefore, even when the viscosity of the liquid UV curable resin cannot be changed, the size of the opening region of the layer opening 18a can be changed, so that the curvature of the lens 20 can be changed. This is an effective method especially when it is necessary to form a lens with an opening diameter smaller than that of the substrate opening 19a. Therefore, the surface-emitting light emitting device 1 that can emit light at a desired light emission angle can be obtained.

  Further, although the electro-optic element described in the present embodiment is the surface-emitting light emitting element 1, the lens 20 can be similarly formed by the photodiode 2. In this case, since the curvature of the lens 20 can be changed, the incident light can be converged and light can be efficiently incident on the light absorption layer 22 that is the light receiving surface. Therefore, the photodiode 2 having high light receiving efficiency can be obtained.

(Second Embodiment)
Next, 2nd Embodiment of this invention is described using FIGS.
FIG. 4 is a schematic cross-sectional view of an electro-optical element having the optical member obtained in the second embodiment. 4A shows a case where the electro-optical element 1 having a lens as the optical member 20 is a surface-emitting light-emitting element as one of the light-emitting elements, and FIG. 4B shows an electro-optic having the lens 20. The case where the element 2 is a photodiode as one of the light receiving elements is shown. Here, the structures of the surface light emitting element 5 and the photodiode 6 are the same as those in the first embodiment. Since the difference between the first embodiment is the structure of the lens 40 as an optical member, the lens 40 will be described using the surface-emitting light emitting element 5. The structure of the lens 40 is the same for the photodiode 6. The operational effects of the surface-emitting light-emitting element 1 or the photodiode 2 on which the lens 40 is formed are substantially the same as those in the first embodiment.

The structure of the lens 40 as an optical member will be described with reference to FIG.
The GaAs substrate 10 has a recess 41 having a substrate opening 41a. An annular layer 40 is formed around the substrate opening 41a.

  The lens 42 as an optical member is formed in a convex shape having a diameter equivalent to the in-substrate lens 42a from the inside of the recess 41 to the substrate opening 19 and the diameter 40a on which the layer 40 is formed. Lens 42b.

  Next, a method for manufacturing an electro-optical element having a lens as an optical member will be described. Here, the surface light emitting element 5 will be described as an example of the electro-optical element.

  FIG. 5A shows a layer forming process. A silicon oxide layer or a silicon nitride layer as the layer 40 is formed on the entire back surface of the GaAs substrate 10 on which the surface light emitting element 5 is formed by the CVD (Chemical Vapor Deposition) method or the like. The surface-emitting light emitting element 5 has the structure described with reference to FIG.

  FIG. 5B shows a layer opening forming step. On the layer 40 formed on the entire back surface of the GaAs substrate 10, a photoresist (not shown) having an opening in a region where the layer opening 40a is to be formed is formed by photolithography. Next, using the photoresist as a mask, the layer 40 is removed by dry etching to form a layer opening 40a. Thereafter, the photoresist is peeled off. Similar to the first embodiment, the layer opening 40 a is formed on the light emitting surface of the surface light emitting element 5, that is, on the optical path emitted from the active layer 12. Note that the layer 40 can be removed by a wet etching method in addition to a dry etching method.

  FIG.5 (c) shows a recessed part formation process. In the recess forming step, the recess 41 is formed using a dry etching method using the layer 40 as a hard mask. The size of the substrate opening 41a included in the recess 41 is almost the same as that of the layer opening because it is processed by the dry etching method.

  FIG. 6A shows the layer processing step. A pattern of the photoresist 27 is formed on the recess 41 and the portion of the layer left in the vicinity of the recess 41 by photolithography. Thereafter, the layer 40 is removed by a dry etching method. Thereby, the size of the outer shape of the layer 40, that is, the layer forming region 40a is determined.

  FIG. 6B shows a resist removal process. After the photoresist 27 is peeled off, scum remaining on the surface of the recess 41 and the layer 40 is ashed. Next, the photoresist 27 is completely removed by cleaning the entire GaAs substrate 10.

  FIG.6 (c) shows an optical member formation process. The lens 42 as an optical member uses an ultraviolet curable resin, as in the first embodiment. First, the entire back surface of the GaAs substrate 10 is subjected to water repellency treatment. Next, a lens precursor 50a is formed in the recess 41 by using a liquid ultraviolet curable resin by a droplet discharge method or a dispenser method. Further, an ultraviolet curable resin is injected to form the lens precursor 50 b up to the layer 40. Since the GaAs substrate 10 holds droplets at the end of the layer 40, the size of the lens precursor 50b is determined by the layer formation region 40a. Thereafter, the lens precursors 50a and 50b are irradiated with ultraviolet rays to cure the ultraviolet curable resin and form the lens 42. In this way, the surface light emitting element 1 having the lens 42 shown in FIG. 4A is obtained.

  Here, the layer formation region 40a can be determined by the pattern of the photoresist in the above layer processing step. Therefore, since the pattern shape and region of the photoresist 27 can be set to some extent freely depending on conditions such as a mask pattern in the resist pattern forming step, the layer forming region 40a can be set freely. In particular, this embodiment is effective when it is desired to make the lens 42 larger than the concave portion 41.

  In the case where the in-substrate lens 42a and the convex lens 42b are formed, they may be formed of different materials or the like in terms of the process or the optical characteristics of the lens 42.

  The effect of this embodiment is the same as that of the first embodiment. That is, it is possible to obtain a surface-emitting light emitting device 1 that can emit light with a desired light emission angle, and to obtain a photodiode 2 with high light receiving efficiency.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG.
FIG. 7 is a cross-sectional view of an optical transmission module using the electro-optical element 1 obtained in the first embodiment or the second embodiment. In the optical transmission module 300a, the surface-emitting light-emitting element array 100 in which the surface-emitting light-emitting elements 1 are arrayed and the photodiode array 200 in which the photodiodes 2 are arrayed are arranged to face each other. The surface-emitting light-emitting element array is electrically connected to the driving substrate 102 having a surface-emitting light-emitting element transmitting circuit, and the photodiode array 200 is electrically connected to the driving substrate 202 having a photodiode receiving circuit by solder bumps 101 and 201, respectively. Connected.

  In the optical transmission module 300 a, light is emitted from each surface light emitting element 1 of the surface light emitting element array 100 by the voltage applied from the driving substrate 102. On the other hand, each photodiode 2 of the photodiode array 200 converts the received light into a current by a voltage from the drive substrate 202.

  The surface-emitting light-emitting element array 100 included in the light transmission module 300a is formed with a lens 20 that reduces the light emission angle, and the photodiode array 200 is also provided with a lens 42 that increases the light receiving efficiency. The optical coupling efficiency can be improved without using an optical waveguide such as an optical fiber. Therefore, it is possible to obtain the optical transmission module 300a in which the trouble of adjusting the optical axis or the like is reduced.

(Fourth embodiment)
A fourth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a cross-sectional view of another optical transmission module using the electro-optical element 1 obtained in the first embodiment or the second embodiment.

  The light transmission module 300b includes the surface-emitting light emitting element array 100, the photodiode array 200, and a pair of mirror devices 400. Here, the surface light emitting element array 100 and the photodiode array 200 are both arranged in parallel on the same surface. The surface light emitting element array 100 is arranged so as to emit light upward in the drawing, and is arranged at a position where the first mirror device 400a reflects the light. On the other hand, the photodiode array is disposed so as to receive light from above, and is disposed at a position where the reflected light from the first mirror device 400a is further reflected by the second mirror device 400b and the reflected light can be received. Has been.

  In this light transmission module 300b, by making the mirror device 400 variable, it is possible to adjust whether light emitted from the surface light emitting element array 100 is received by the photodiode array 200 or not. Thereby, the mirror device 400 can function as a switch in the optical transmission module 300b.

(Fifth embodiment)
FIG. 9 shows a fifth embodiment of the present invention. FIG. 9 is a cross-sectional view of another optical transmission module using the electro-optical element 1 obtained in the first embodiment or the second embodiment.

  The light transmission module 300 c includes the surface-emitting light emitting element array 100, the photodiode array 200, and the optical fiber 500. Here, the light emitting part of the surface light emitting element array 100 and the light receiving part of the photodiode array 200 are connected by an optical fiber 500. By connecting the light emitting unit and the light receiving unit with the optical fiber 500, the optical coupling efficiency of the light emitted from the surface light emitting element array 100 can be stabilized. Further, it becomes easy to adjust the optical axes of the surface-emitting light emitting element array 100, the photodiode array 200, and the optical fiber 500.

(A) is a schematic cross-sectional view showing an optical functional element when the electro-optical element is a surface-emitting light emitting element in the first embodiment, and (b) shows an optical functional element when the electro-optical element is a photodiode. FIG. (A)-(c) is process sectional drawing which shows the manufacturing process of an optical functional element. (A)-(c) is process sectional drawing which shows the manufacturing process of an optical functional element. (A) is a schematic cross-sectional view showing an optical functional element when the electro-optical element is a surface-emitting light emitting element in the second embodiment, and (b) shows an optical functional element when the electro-optical element is a photodiode. FIG. (A)-(c) is process sectional drawing which shows the manufacturing process of an optical functional element. (A)-(c) is process sectional drawing which shows the manufacturing process of an optical functional element. Sectional drawing which shows an example of the optical transmission module in 3rd Embodiment. Sectional drawing which shows an example of the optical transmission module in 4th Embodiment. Sectional drawing which shows an example of the optical transmission module in 5th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 3 ... Surface emitting type light emitting element which has a lens, 2, 4 ... Photodiode which has a lens, 5 ... Surface emitting type light emitting element, 6 ... Photodiode, 10 ... GaAs substrate, 11 ... 1st mirror layer, 12 ... Active layer, 13 ... second mirror layer, 14 ... current confinement layer, 15, 24 ... insulating layer, 16, 25 ... first electrode (cathode), 17, 26 ... second electrode (anode), 18 ... as layer Metal layer, 18a ... layer opening, 18b ... layer wall, 19, 41 ... recess, 19a, 41a ... substrate opening, 19b, 41b ... bottom surface of recess, 20, 42 ... lens as optical member, 20a, 42a In-substrate lens, 20b, 42b ... Convex lens, 21 ... Mirror layer, 22 ... Light absorption layer, 23 ... Contact layer, 27 ... Photoresist as mask, 28 ... Droplet ejection device, 29 ... Lens precursor, 30a, DESCRIPTION OF SYMBOLS 0a ... Lens precursor in substrate, 30b, 50b ... Convex lens precursor, 40 ... Hard mask as a layer, 40a ... Hard mask formation area, 100 ... Surface emitting light emitting element array, 101, 201 ... Solder bump, 102 , 202 ... driving substrate, 103, 203 ... mirror device, 200 ... photodiode array, 300a, 300b, 300c ... optical transmission module, 500 ... optical fiber.

Claims (8)

An electro-optic element is formed on the surface, and a substrate having a recess provided with a substrate opening on the back surface on the light path of the light-emitting surface or the light-receiving surface of the electro-optic element;
A layer having a layer opening on the back surface of the substrate on the optical path;
And an optical member having a size defined by the wall surface of the layer opening, which is formed in a convex shape inside the recess and on the back side of the substrate. The electro-optic element according to claim 1,
The electro-optic element, wherein the layer opening is smaller than the area of the substrate opening and is included in the substrate opening. An electro-optic element is formed on the surface, and a substrate having a recess provided with a substrate opening on the back surface on the light path of the light-emitting surface or the light-receiving surface of the electro-optic element;
A layer formed in an annular shape around the substrate opening;
An electro-optical element having an optical member formed on the layer in a size that is defined by the outer shape of the layer, in a convex shape inside the recess and on the back side of the substrate. A layer forming step of forming a layer having a layer opening formed on the light path of the light emitting surface or the light receiving surface of the electro optical element on the back surface of the substrate on which the electro optical element is formed;
A recess forming step of forming a recess on the optical path through the layer opening;
By injecting the material of the optical member from the mask opening into the recess, the inside of the recess and the size defined by the wall surface of the layer opening in a convex shape on the back side of the substrate An optical member forming process for forming an optical member. A method for producing an electro-optic element according to claim 4,
In the layer forming step, the resist is left on the back surface of the substrate on which the electro-optic element is formed, in a layer opening formed on the light path of the light-emitting surface or the light-receiving surface of the electro-optic element. A resist pattern forming step of patterning a resist;
A hard mask forming step of forming a hard mask on the entire back surface of the substrate;
And a layer opening forming step of forming the layer opening by patterning the layer by peeling the layer formed on the resist together with the resist. It is a manufacturing method of the optical functional element according to claim 4 or 5,
The method for manufacturing an electro-optic element, wherein in the recess forming step, the layer opening is formed so as to be smaller than a substrate opening included in the recess and included in the substrate opening. A layer forming step of forming a layer on the entire back surface of the substrate on which the electro-optic element is formed;
A layer opening forming step of processing the layer to form a layer opening on the light path of the light emitting surface or the light receiving surface of the electro-optic element;
Forming a recess having a substrate opening on the optical path on the back surface of the substrate, using the layer as a mask;
A layer processing step of processing so as to leave the layer in a ring shape around at least the substrate opening;
By injecting the material of the optical member into the recess from the layer opening, the inner surface of the recess has a size defined by the outer shape of the layer in a convex shape on the back surface side of the substrate. And an optical member forming step of forming the optical member formed on the electro-optical element.   An optical transmission module comprising the electro-optic element according to claim 1.

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