JP2009129929A - Semiconductor light-emitting chip equipped with reflecting mirror - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting chip highly efficient in using output light. <P>SOLUTION: This point light source LED chip (semiconductor light-emitting chip) 10 includes a support layer 14 rigidly combined with one side of the point light source LED chip 10 while having a recessed hole 46 to optically expose a light transmitting face 42 on the bottom face, and a reflecting mirror 48 formed on the inner peripheral surface of the recessed hole 46 to reflect light entering the inner peripheral surface out of light output from the light transmitting face 42. Thereby, even light slanting at a prescribed angle or larger to an optical axis A is made usable by being reflected by the reflecting mirror 48. For example, light is forced to enter the end face 56 of an optical fiber, and the point light source LED chip 10 highly efficient in using output light can be obtained. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a semiconductor light-emitting chip including a reflecting mirror that further improves the light output efficiency of a semiconductor light-emitting chip such as a point light source LED that is preferably used as a light source for supplying light to an optical fiber.

  A semiconductor light-emitting chip in which a light transmission surface for outputting light, such as a point light source LED, is locally provided on one side is, for example, an active layer provided in a semiconductor multilayer film epitaxially grown on a substrate and its activity A current confinement structure in which current concentrates in a part of the layer, and light emitted locally by current concentration in a part of the active layer is locally provided on one surface of the output side The light is output through the light transmission surface. Such a semiconductor light emitting chip is required to have higher luminous efficiency, and various devices have been devised.

For example, in Patent Document 1, there is provided a surface light emitting diode in which a reflective layer is provided on the substrate side of the active layer, and light emitted from the active layer toward the substrate side is reflected by the reflective layer toward the light transmission surface side, thereby improving the light emission efficiency. Proposed. In Patent Document 2, a semiconductor light emitting device that includes a pair of reflection films sandwiching an active layer, forms a cavity that resonates light between the pair of reflection films, and outputs the resonance light to increase the light emission efficiency. Proposed. Further, in Patent Document 3, the quantum well layer having a reduced thickness is used as the light emitting layer, and the light emission efficiency is improved by positioning the quantum well layer on the antinode of light that is resonantly resonated between the pair of reflective films. Surface emitting devices have been proposed.
JP 09-289336 A JP 2003-332615 A JP 2002-204026 A

  However, in the above-described conventional semiconductor light emitting device, light output from a light transmission surface locally provided on one surface, that is, a light output surface, is not necessarily output in a fixed direction, but is output obliquely with respect to the optical axis. On the other hand, oblique light of a predetermined angle or more is wasted without being used, and the light emission efficiency was substantially reduced.

  The present invention has been made against the background described above, and an object of the present invention is to provide a semiconductor light emitting chip with high utilization efficiency of output light.

  The gist of the invention according to claim 1 for achieving the above object is: (a) a semiconductor light-emitting chip in which a light transmitting surface from which light is output is locally provided on one surface, and (b) A support layer made of a cured photosensitive resin, fixed on the one surface, and formed with a concave hole that optically exposes the light transmitting surface to the bottom surface; and (c) an inner peripheral surface of the concave hole. And a reflecting mirror that reflects light incident on the inner peripheral surface of the light that is formed and output from the light transmitting surface.

  A gist of the invention according to claim 2 is that, in the invention according to claim 1, the support layer is formed by curing a photosensitive resin applied on the one surface.

 The gist of the invention according to claim 3 is that, in the invention according to claim 2, the support layer is formed in a state where the photosensitive resin applied on the one surface is pressed by a light transmission mold. That is, it is cured by light transmitted through the light transmission mold.

 Further, the gist of the invention according to claim 4 is that, in the invention according to claim 2, the support layer is made of a photosensitive resin coated on the one surface, and the light transmittance at the boundary of the exposure pattern is continuous. And being cured by light transmitted through a gray scale mask that changes with time.

  Further, the gist of the invention according to claim 5 is that, in the invention according to claim 1, the support layer is formed by molding and the resin sheet after the reflecting mirror is formed on the inner peripheral surface of the recessed hole is the one surface. It is to be glued on top.

  A gist of the invention according to claim 6 is that, in the invention according to any one of claims 1 to 5, the concave hole has an inner peripheral surface formed in a partial spherical shape or a partial parabolic shape. It is to have.

  The gist of the invention according to claim 7 is that, in the invention according to any one of claims 1 to 6, the concave hole includes a reflecting mirror portion on which the reflecting mirror is formed, and the reflecting mirror portion. In order to fit the tip portion of the optical fiber on the side away from the one surface, the reflector portion and one or more fitting portions concentric with the reflecting mirror portion are provided.

  The gist of the invention according to claim 8 is that, in the invention according to claim 7, the concave hole has a tapered guide portion for guiding the tip portion of the optical fiber to the fitting portion. It exists in having on the side spaced apart from the said one surface.

  According to the semiconductor light-emitting chip provided with the reflecting mirror of the invention according to claim 1, the concave hole that is made of the cured photosensitive resin and is fixed on one surface and optically exposes the light transmission surface to the bottom surface. From the formed support layer and a reflecting mirror that is formed on the inner peripheral surface of the concave hole and reflects light incident on the inner peripheral surface of the light output from the light transmitting surface, Even light oblique to the optical axis at a predetermined angle or more can be used after being reflected by the reflecting mirror. For example, the light is incident on the end face of the optical fiber. Therefore, a semiconductor light emitting chip with high utilization efficiency of output light can be obtained.

  Moreover, according to the semiconductor light-emitting chip provided with the reflecting mirror of the invention according to claim 2, the support layer is formed by curing the photosensitive resin applied on the one surface. However, there exists an advantage comprised easily from the resist material used for the photolithography of a semiconductor manufacturing process.

  Moreover, according to the semiconductor light-emitting chip provided with the reflecting mirror of the invention according to claim 3, the support layer has the light transmission state in a state where the photosensitive resin applied on the one surface is pressed by the light transmission mold. Since it is cured by the light transmitted through the mold, the concave hole of the support layer is formed with high accuracy following the molding surface of the light transmission mold.

  Moreover, according to the semiconductor light-emitting chip provided with the reflecting mirror of the invention according to claim 4, the support layer is formed of a photosensitive resin coated on the one surface, and the light transmittance at the boundary of the exposure pattern is continuous. Since it is hardened by the light transmitted through the changing gray scale mask, there is an advantage that the concave hole is formed relatively easily.

  Moreover, according to the semiconductor light-emitting chip provided with the reflecting mirror of the invention according to claim 5, the support layer is molded on the resin sheet after the reflecting mirror is formed on the inner peripheral surface of the recessed hole. Since they are bonded, there is an advantage that a support layer having a concave hole and a reflecting mirror provided on the inner peripheral surface thereof can be provided relatively easily. In addition, by forming the reflecting mirror or the like in a state where the resin sheet is separate from the main body, there is an advantage that the range of material selection is widened compared to the case where it is directly formed on the main body.

  Moreover, according to the semiconductor light-emitting chip provided with the reflecting mirror of the invention according to claim 6, the concave hole has an inner peripheral surface formed in a partial spherical shape or a partial parabolic shape. Since the light reflected by the mirror is output at an angle that approaches the optical axis direction efficiently, the light emission efficiency or utilization efficiency is further enhanced.

  According to the semiconductor light-emitting chip including the reflecting mirror of the invention according to claim 7, the concave hole is formed on the side of the reflecting mirror portion where the reflecting mirror is formed and the one surface of the reflecting mirror portion separated from the one surface. Since it includes one or two or more fitting parts concentric with the reflecting mirror part for fitting the tip part of the optical fiber, if the tip part of the optical fiber is fitted into the fitting part, the tip part is Since it is positioned directly with respect to the light transmission surface of the semiconductor light emitting chip, the relative position between the light transmission surface and the end surface of the optical fiber can be maintained, and the positioning accuracy of the end surface of the optical fiber with respect to the light transmission surface is good. Can be secured. As a result, it is possible to suppress the light transmission efficiency between the light transmission surface and the end surface of the optical fiber from being lowered due to variations in the relative position with respect to the optical fiber.

  According to the semiconductor light emitting chip including the reflecting mirror of the invention according to claim 8, the concave hole has a tapered guide portion for guiding the tip end portion of the optical fiber to the fitting portion. Therefore, positioning and assembling of the tip portion of the optical fiber with the semiconductor light emitting chip is further facilitated.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a view of a semiconductor light emitting chip, that is, a point light source LED chip 10 according to an embodiment of the present invention, as viewed from one side where light is output. 2 is a diagram showing a chip structure of the point light source LED chip 10 of FIG. 1, and is a cross-sectional view taken along line II-II in FIG. As shown in FIGS. 1 and 2, the point light source LED chip 10 having a substantially rectangular parallelepiped shape includes a reflecting mirror 48 for increasing the utilization efficiency of output light, and a support layer 14 for holding the optical fiber 12. It comprises a chip-like main body 16 that outputs light. The optical fiber 12 is of a clad type and includes a core portion 12a and a clad portion 12b on the outer periphery thereof.

  In FIG. 2, the body portion 16 of the point light source LED chip 10 is sequentially laminated on a substrate 18 made of, for example, an n-GaAs single crystal using, for example, an MOCVD (metal organic chemical vapor deposition) method. , N-AlGaAs single crystals and n-AlAs single crystals 32 pairs stacked alternately, multilayer reflective layer 20, i-AlGaAs first barrier layer 22, i-GaAs active layer 24, i-AlGaAs A second barrier layer 26, a multilayer reflective layer 28 in which nine pairs of p-AlAs and p-AlGaAs are alternately stacked, a clad layer 30 made of p-AlGaAs, and a current blocking layer 32 made of an n-AlGaAs single crystal. It has. Further, an upper electrode 34 made of AuZn / Au eutectic is formed on the upper surface of the current blocking layer 32, and a bonding pad 35 made of Au is formed on a part of the upper electrode 34 by vapor deposition or sputtering. A lower electrode 36 made of AuGe / Ni / Au eutectic is formed on the lower surface by vapor deposition or sputtering.

  A circular recess 40 is formed inside the through hole 38 provided in the vicinity of the center of the upper electrode 34 in the width direction on the current blocking layer 32 by means of, for example, photo-etching, and the bottom surface of the through hole 38 is light-transmitted. Corresponds to the light transmitting surface 42 from which the light is output. That is, the light transmitting surface 42 from which light is output is locally provided on one surface of the main body 16, that is, the upper surface on which the upper electrode 34 is provided. Further, a high concentration diffusion region 44 in which a p-type dopant such as Zn is diffused at a high concentration is formed in the clad layer 30 and the current blocking layer 32 in the region indicated by the hatched area in FIG. Thus, in the high-concentration diffusion region 44, the conductivity of the cladding layer 30 is enhanced and the conductivity type of the current blocking layer 32 is inverted to be p-type, and only the portion corresponding to the recess 40 is formed. A current confinement structure is formed that can be energized.

  In this embodiment, the first barrier layer 22, the active layer 24, and the second barrier layer 26 constitute a light emitting layer having a quantum well structure, and the multilayer film layer 28 constitutes a notch filter.

  The support layer 14 is made of a cured photosensitive resin known as a so-called permanent resist, and has a concave hole 46 for optically exposing the light transmission surface 42 so as to surround the light transmission surface 42. And is fixed on one surface, that is, the upper surface of the main body portion 16. The optical exposure means that the light transmitting surface 42 and the space in the recessed hole 46 are optically coupled, that is, the light output from the light transmitting surface 42 can propagate directly to the space in the recessed hole 46. This means not only a state where the light transmission surface 42 is mechanically exposed but also a state where the light transmission surface 42 is covered with a thin resin or the like capable of transmitting light of the output light. The support layer 14 has a light transmission mold 63 in a state where, for example, an epoxy-based photosensitive resin applied or laminated on one surface of the main body 16, that is, the upper electrode 34 is pressed by the light transmission mold 63. It is polymerized and cured by light passing through. The light transmission mold 63 is made of a material capable of transmitting light, that is, electromagnetic waves, capable of polymerizing the photosensitive resin. The light mentioned here does not necessarily mean visible light, but is a concept including light having a shorter wavelength or longer wavelength.

  The concave hole 46 is directed toward the end surface 56 of the optical fiber 12 with light incident on the inner peripheral surface of the light output from the light transmitting surface 42 on the inner peripheral surface formed in a partial spherical shape or a partial paraboloid shape. A reflecting mirror part 50 in which a reflecting mirror 48 is formed, and a cylindrical inner surface adjacent to the one surface of the reflecting mirror part 50, that is, the side away from the light transmitting surface 42, and the tip of the optical fiber 12 is fitted. A cylindrical surface fitting portion 54 for insertion is provided so as to be concentric with the optical axis A which is a vertical line (normal line) passing through the center of the light transmission surface 42. The reflecting mirror 48 is composed of a metal layer fixed by chemical plating, metal vapor deposition, sputtering, or the like of silver, aluminum, or an alloy containing either of them as a main component. Further, the fitting portion 54 is configured such that the tip end portion of the optical fiber 12 is positioned so that at least the end surface 56 of the core portion 12a of the optical fiber 12 is concentrically opposed to almost the entire surface of the light transmission surface 42. .

  In the point light source LED chip 10 configured as described above, when a pn forward current flows between the lower electrode 36 and the upper electrode 34, a current flows through a path passing through the above-described energizable region, and thereby the above-described activity Layer 24 is excited to emit light locally. At this time, the first barrier layer 22, the active layer 24, and the second barrier layer 26 are provided in an optical resonator constituted by the multilayer reflective layer 20 and the notch filter (multilayer film layer 28). For this reason, light satisfying the resonance condition is suitably emitted from the light transmission surface 42. That is, the point light source LED chip 10 shown in FIG. 2 is a resonant cavity light emitting diode (RC-LED) having an internal optical resonator, and the notch filter corresponds to the multilayer reflective layer 28 on the light transmission surface 42 side. To do.

  FIG. 3 is a process diagram for explaining a main part of the manufacturing process of the point light source LED chip 10, and FIG. 4 is a schematic diagram for explaining an implementation state in a main part stage of the manufacturing process shown in FIG. 3 and 4, the disk-shaped semiconductor light emitting chip wafer 60 having the same epitaxial multilayer structure as that of the main body 16 and arranged in the plane direction thereof has, for example, the following processes: It is assumed that it has been prepared in advance. First, the multilayer reflective layer 20 to the current blocking layer 32 are sequentially grown on the substrate 18 by MOCVD or the like and stacked. Subsequently, a recess 40 is dug in the current blocking layer 32 by means such as photo etching. Subsequently, a p-type dopant such as Zn is diffused from the current blocking layer 32 side by means such as thermal diffusion to form a current confinement structure. Finally, the lower electrode 36 is formed on the lower surface of the substrate 18 and the upper electrode 34 is formed on the upper surface of the current blocking layer 32 by means such as vapor deposition or sputtering, whereby the semiconductor light emitting chip wafer 60 is manufactured. Hereinafter, the manufacturing process of the point light source LED chip 10 will be described with reference to FIGS. The support layer 14 in the present embodiment is formed by, for example, an imprint technique.

  First, in the resin coating process P1, as shown in FIG. 4A, an epoxy photosensitive material is formed at a predetermined position on the upper electrode 34 of the semiconductor light emitting chip wafer 60, that is, a desired position where the support layer 14 is to be formed. Resin (resist) 62 is applied by a predetermined amount, for example, by screen printing. In this embodiment, a photosensitive resin 62, which is a photocurable resin that is photopolymerized when irradiated with ultraviolet rays, is used. For example, it is cured when irradiated with far infrared rays, X-rays, electron beams, or the like. It may be another photo-curing resin, a thermosetting resin that is cured by applying heat, or a two-component mixed type curable resin that is subsequently cured by mixing different resins.

  Next, in the mold pressing step P2, as shown in FIG. 4B, the surface shape of the support layer 14 to be formed on the upper electrode 34 of the semiconductor light emitting chip wafer 60 is formed with a surface shape in which the irregularities are reversed. A light transmission mold 63 having a surface 61 made of, for example, a glass plate, a resin plate or the like is pressed against a predetermined position on the semiconductor light emitting chip wafer 60 on which the photosensitive resin 62 is selectively applied.

  Next, in the curing step P3, as shown in FIG. 4C, the one surface of the semiconductor light emitting chip wafer 60 to which the photosensitive resin 62 is applied is pressed through the pressed light transmission mold 63. Light that passes through the light transmission mold 63, for example, ultraviolet light U is irradiated. Accordingly, the concave portion having a partially spherical or partially parabolic reflecting mirror portion 50 on which the reflecting mirror 48 is formed in a film forming step P4 described later and a fitting portion 54 for fitting the tip of the optical fiber 12. The support layer 14 having the holes 46 is formed. Thereafter, heat treatment is performed at about 150 ° C., for example, as necessary. Thereby, hardening is further accelerated | stimulated and the adhesiveness of the support layer 14 and the upper electrode 34 improves. In addition, when the resin applied in the resin application step P1 is another kind of photo-curing resin or thermosetting resin, a corresponding light or heat for curing the resin is applied. Further, when the resin applied in the resin application step P1 is a two-component mixed type curable resin, in the curing step P3, it is not necessary to add the light or the like until the resin 62 is cured instead. Alternatively, the pressed light transmission mold 63 is held as it is until substantially cured.

  Next, in the film forming step P4, at least chemical plating or metal deposition is performed on the surface corresponding to the reflecting mirror 48 of the concave hole 46 of the formed support layer 14, that is, the surface including the inner peripheral surface of the reflecting mirror portion 50. Alternatively, a metal layer such as silver (Ag) or aluminum (Al) is deposited by means such as sputtering. FIG. 4 (d) shows this state. Note that at least the portion including the light transmission surface 42 where the metal layer is unnecessary, that is, the portion excluding the inner peripheral surface of the reflecting mirror portion 50 is removed by lift-off or etching.

  Next, in the inspection process P5, the semiconductor light emitting chip wafer 60 on which the support layer 14 is formed is set on a measurement stage of an inspection apparatus (not shown), the quality of each element is inspected using a probe, and the subsequent dicing process P6. In FIG. 4, the semiconductor light emitting chip wafer 60 is cut into individual chips, whereby the point light source LED chip 10 as shown in FIG. 4E is obtained. As a result, the support layer 14 and the reflecting mirror 48 are generated before dicing, thereby enabling high-level alignment using photolithography technology and wafer bonding technology. In addition, the manufacturing process can be simplified by batch processing a large number of chips.

  As described above, according to the point light source LED chip 10 provided with the reflecting mirror 48 of the present embodiment, the concave portion fixed on one surface of the point light source LED chip 10 and optically exposing the light transmission surface 42 to the bottom surface. A support layer 14 having a hole 46, and a reflecting mirror 48 that is formed on the inner peripheral surface of the concave hole 46 and reflects light incident on the inner peripheral surface of the light output from the light transmitting surface 42; Therefore, even the oblique light with a predetermined angle or more with respect to the optical axis A is reflected by the reflecting mirror 48 and can be used. For example, the light is incident on the end face 56 of the optical fiber 12. Therefore, the point light source LED chip 10 with high utilization efficiency of output light is obtained.

  Incidentally, FIG. 5 shows a current applied to an RC-LED (resonant cavity light emitting diode) having an internal optical resonator such as the main body 16 of the point light source LED chip 10 of this embodiment and a light distribution pattern, that is, a directivity. It is the figure which showed an example of the relationship with sex. In FIG. 5, the radial direction of the semicircle indicates the relative value of the light emission output with the maximum value of the light emission output when the current is passed as 1.0, and the circumferential direction of the semicircle indicates the normal line of the light transmission surface 42 Each angle formed by the traveling direction of light is shown. As shown in this figure, the light distribution pattern of the point light source LED chip 10 (RC-LED) is generally a spherical line L called a Lambert distribution similar to a normal LED at room temperature, although it depends on the design. The directivity shown is shown, but in a high temperature range or a low temperature range within the allowable temperature range, it is represented by a rabbit ear-shaped diagram R called rabbit ear. That is, the angle taken by the light emitted from the point light source LED chip 10 is often oblique with respect to the optical axis A of the light transmission surface 42. Further, as the current applied to the point light source LED chip 10 increases from 10 mA to 20 mA and then 50 mA, the angle range taken by the light emitted from the light transmission surface 42 changes (narrows). This is due to the fact that more heat is applied to the point light source LED chip 10 by applying a larger current. That is, the light distribution pattern of the point light source LED chip 10 depends on the temperature. Therefore, in the RC-LED as in the present embodiment, if the point light source LED chip 10 including the reflecting mirror 48 as described above is used, the effect that the utilization efficiency of the output light is further obtained. That is, the light emitted obliquely with respect to the optical axis A of the main light transmitting surface 42 is reliably reflected by the reflecting mirror 48 and can be used, and is also emitted from the light transmitting surface 42 due to a temperature change. Even if the angle range of the light to be changed changes, the utilization efficiency of the output light is hardly changed.

  Moreover, according to the point light source LED chip 10 provided with the reflecting mirror 48 of the present embodiment, the support layer 14 is obtained by curing the resin (photosensitive resin) 62 applied on the one surface. The support layer 14 has an advantage that it is easily composed of a resist material used in photolithography, which is known as a semiconductor manufacturing method.

  Moreover, according to the point light source LED chip 10 provided with the reflecting mirror 48 of the present embodiment, the support layer 14 has the resin (photosensitive resin) 62 applied on the one surface pressed by the light transmission mold 63. In this state, the concave hole 46 of the support layer 14 is formed with high accuracy following the molding surface 61 of the light transmission mold 63 because it is cured by ultraviolet light (light) that passes through the light transmission mold 63. Molded.

  Further, in the point light source LED chip 10 provided with the reflecting mirror 48 of the present embodiment, when the reflecting mirror 48 is formed of a metal layer fixed to the inner peripheral surface of the recessed hole 46 by chemical plating, There is an advantage that the reflecting mirror 48 composed of a dense metal layer is easily provided.

  Further, in the point light source LED chip 10 provided with the reflecting mirror 48 of the present embodiment, when the reflecting mirror 48 is composed of a metal layer fixed to the inner peripheral surface of the concave hole 46 by metal vapor deposition or sputtering, There is an advantage that the reflecting mirror 48 is easily provided.

  Further, according to the point light source LED chip 10 provided with the reflecting mirror 48 of the present embodiment, the concave hole 46 is an inner peripheral surface formed in a partial spherical shape or a partial parabolic shape so as to be concentric with the optical axis A. Therefore, the light reflected by the reflecting mirror 48 is output at an angle that efficiently approaches the direction of the optical axis A, so that the light emission efficiency or the utilization efficiency is further enhanced.

  Moreover, according to the point light source LED chip 10 provided with the reflecting mirror 48 of the present embodiment, the recessed hole 46 is separated from the reflecting mirror part 50 in which the reflecting mirror 48 is formed and the one surface of the reflecting mirror part 50. A fitting portion 54 for fitting the distal end portion of the optical fiber 12 is provided on the side. For this reason, if the tip of the optical fiber 12 is fitted into the fitting portion 54, the tip is positioned directly with respect to the light transmission surface 42 of the point light source LED chip 10, and the light transmission surface 42 and the optical fiber 12 are aligned. Since the relative position with respect to the end surface 56 is maintained, the positioning accuracy of the end surface 56 of the optical fiber 12 with respect to the light transmission surface 42 can be ensured satisfactorily. As a result, the light transmission efficiency between the light transmission surface 42 and the end surface 56 of the optical fiber 12 is suppressed from being reduced due to variations in the relative position with respect to the optical fiber 12.

  Next, another embodiment of the present invention will be described. In the following description of the embodiments, portions that are the same as those of the above-described embodiments are denoted by the same reference numerals and description thereof is omitted.

  The point light source LED chip 64 in another embodiment of the present invention has the same configuration as that shown in FIGS. 1 and 2 except that the fitting portion 54 is not provided in the recessed hole 46 of the support layer portion 14.

  FIG. 6 is a process diagram for explaining a main part of the manufacturing process of the point light source LED chip 64 in another embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. FIG. 7 is a schematic diagram for explaining an implementation state at a main stage of the manufacturing process shown in FIG. Hereinafter, the manufacturing process of the point light source LED chip 64 will be described with reference to FIGS. The support layer 70 in the present embodiment is formed by a photolithography technique.

  First, in the photoresist coating process P1, as shown in FIG. 7A, an epoxy photosensitive resin (photoresist) is formed on the upper electrode 34 of the semiconductor light emitting chip wafer 60 manufactured in the same manner as in the first embodiment. 62) is applied to a target thickness by a spin coater or spraying. In this embodiment, the photosensitive resin 62 is a negative type UV resist which is photopolymerized by being exposed to ultraviolet light U and becomes hardly soluble. However, the photosensitive resin 62 is photodecomposed by being exposed to ultraviolet light. A positive-type UV resist that is easily soluble may be used, or a resist that is photopolymerized or photodecomposed by other light such as X-rays or an electron beam may be used.

  Next, in the mask exposure step P2, as shown in FIG. 7B, the photosensitive resin 62 applied to one surface of the semiconductor light emitting chip wafer 60 is a photomask in which the light transmittance is inclined, that is, exposure. A gray scale mask 66 in which the light transmittance of the boundary 65 of the pattern is continuously changed is used, and the pattern is exposed to the ultraviolet light U through the gray scale mask 66. At this time, a pattern having an exposed portion, an unexposed portion, and a portion whose exposure amount is continuously changed from the exposed portion to the unexposed portion is generated on the photosensitive resin 62. . The portion where the exposure amount is continuously changed is a portion corresponding to the reflecting mirror 48. Here, although ultraviolet rays are irradiated in this embodiment, if the resist applied in the photoresist coating process P1 is other than the UV resist, the corresponding light or electron beam is irradiated.

  Next, in the developing step P3, a developing solution that dissolves the photosensitive resin 62 is used, and the photosensitive resin 62 that is not exposed and part of the portion where the exposure amount is continuously changed is removed. A support layer 70 having a concave hole 46 having a partially spherical or partially parabolic reflecting mirror portion 50 in which the reflecting mirror 48 is formed in a film forming step P5 described later as shown in FIG. 7 (c) is formed. The

  Next, heat treatment is performed at around 150 ° C. in the baking step P4. As a result, the developer that swells the support layer 70 during development can be removed, the support layer 70 is cured, and the adhesion between the support layer 70 and the upper electrode 34 is improved.

  Subsequent film forming steps P5 to P7 correspond to film forming steps P4 to P6 in Example 1, and a point light source LED chip 64 as shown in FIG.

  According to the point light source LED chip 64 provided with the reflecting mirror 48 of the present embodiment, the support layer 70 has the photosensitive resin 62 coated on the one surface continuously having light transmittance at the boundary 65 of the exposure pattern. Since it is hardened by the light transmitted through the changing gray scale mask 66, there is an advantage that the concave hole 46 is formed relatively easily.

  The point light source LED chip 72 according to another embodiment of the present invention has the same configuration as that shown in FIGS. 1 and 2 except that the support layer 14 is laminated on the coupling layer 74 fixed on the upper surface of the main body 16. is there.

  FIG. 8 is a process diagram for explaining the main part of the manufacturing process of the point light source LED chip 72 in another embodiment of the present invention, and corresponds to FIG. 3 of the first embodiment. FIG. 9 is a schematic diagram for explaining an implementation state at a main stage of the manufacturing process shown in FIG. The resin sheet 76 shown in FIG. 9 includes a plate-like connecting layer 74 in which a rectangular through hole (not shown) that exposes the upper electrode 34 is formed, and the concave portion provided on the surface of the connecting layer 74 at a predetermined distance. And a support layer 14 having a reflecting mirror 48 formed on the inner peripheral surface of the hole 46, and is molded by imprint technology through the same steps as the resin coating step P1 to the curing step P3 in FIG. Prepared in advance. In this embodiment, both the coupling layer 74 and the support layer 14 are made of a photosensitive resin. However, the support layer 14 may be a material different from that of the coupling layer 74, for example, a semiconductor substrate such as GaAs or Si, a metal such as silver or aluminum, or a resin plate such as silicon resin. In addition, the resin sheet 76 may be manufactured by means of a photolithography technique that undergoes the same processes as the photoresist coating process P1 to the development process P3 in FIG.

  Hereinafter, the manufacturing process of the point light source LED chip 72 will be described with reference to FIGS. The point light source LED chip 72 in the present embodiment is manufactured using a technique for bonding the support layer 14 in a wafer state. First, in the bonding step P1, an adhesive made of epoxy resin or the like is applied on the one surface except for the upper electrode 34 of the semiconductor light emitting chip wafer 60 manufactured in the same manner as in Example 1, and the upper electrode is applied. The prepared resin sheet 76 is pressed and bonded to a predetermined position on 34. Here, when the connecting layer 74 is made of Si, it may be bonded by Si—Si bonding, or when the connecting layer 74 is made of Au, it may be bonded by Au—Au bonding. Thereafter, heat treatment is performed at about 150 ° C., for example, as necessary. Thereby, the adhesiveness of the resin sheet 76 and the upper electrode 34 improves.

  The subsequent inspection steps P2 to dicing P3 correspond to the inspection steps P5 to dicing P6 in the first embodiment, and the point light source LED chip 72 is obtained through the same procedure. In the case where the reflecting mirror 48 is not formed in advance on the resin sheet 46, a film formation configuration similar to the film formation process P4 of Example 1 is provided prior to the inspection process P2.

  According to the point light source LED chip 72 having the reflecting mirror 48 of the present embodiment, the support layer 14 is molded and the resin sheet 76 after the reflecting mirror 48 is formed on the inner peripheral surface of the recessed hole 46 is the above-described resin sheet 76. Since it is bonded on one surface, there is an advantage that the support layer 14 in which the concave hole 46 and the reflecting mirror 48 are provided on the inner peripheral surface thereof is provided relatively easily.

  FIG. 10 is a view for explaining the configuration of a point light source LED chip 78 in another embodiment of the present invention, and corresponds to FIG. The point light source LED chip 78 of this embodiment has the same configuration as that shown in FIGS. 1 and 2 except that the shape of the recessed hole 46 formed in the support layer 14 is different. That is, the point light source LED chip 78 is different in that a tapered fitting part 80 is provided in place of the fitting part 54 in the recessed hole 46.

  As shown in FIG. 10, the concave hole 46 of this embodiment is incident on the inner peripheral surface of the light output from the light transmitting surface 42 on the inner peripheral surface formed in a partial spherical shape or a partial parabolic shape. The reflecting mirror part 50 in which the reflecting mirror 48 that reflects the light to be reflected toward the end face 56 of the optical fiber 12 is formed, and adjacent to the side of the reflecting mirror part 50 that is separated from the one surface (the light transmitting surface 42), the light A vertical line passing through the center of the light transmitting surface 42 is formed with a tapered surface fitting portion 80 which is formed in a tapered surface shape having a larger diameter as the distance from the transmitting surface 42 increases. To be concentric with the optical axis A.

  According to the point light source LED chip 78 provided with the reflecting mirror 48 of the present embodiment, the tapered fitting portion 80 formed in the concave hole 46 has a larger diameter toward the opening edge of the concave hole 46. Therefore, it becomes easy to guide the tip end portion of the optical fiber 12 into the tapered fitting portion 80 and fit it, so that the tip portion of the optical fiber 12 and the point light source LED chip 78 are more easily positioned and assembled. It becomes. That is, the tapered fitting part 80 functions as a fitting part into which the tip part of the optical fiber 12 is fitted and a tapered guide part that guides the optical fiber 12 to the fitting part.

  FIG. 11 is a diagram for explaining the configuration of a point light source LED chip 82 according to another embodiment of the present invention, and corresponds to FIG. The point light source LED chip 82 of this embodiment has the same configuration as that shown in FIGS. 1 and 2 except that the shape of the recessed hole 46 formed in the support layer 14 is different. That is, the point light source LED chip 82 is different in that a tapered guide portion 84 is provided in the recessed hole 46 subsequent to the fitting portion 54.

  As shown in FIG. 11, the recessed hole 46 of this embodiment is incident on the inner peripheral surface of the light output from the light transmitting surface 42 on the inner peripheral surface formed in a partial spherical shape or a partial parabolic shape. The reflecting mirror part 50 in which the reflecting mirror 48 which reflects the light to be reflected toward the end surface 56 of the optical fiber 12 is formed, and the cylindrical part adjacent to the side away from the one surface (the light transmitting surface 42) of the reflecting mirror part 50 The fitting hole portion 54 is formed in a tapered surface shape having a diameter that increases with distance from the light transmission surface 42 adjacent to the fitting hole portion 54. And a tapered guide portion 84 for guiding to the optical axis A so as to be concentric with the optical axis A which is a vertical line passing through the center of the light transmission surface 42.

  According to the point light source LED chip 82 provided with the reflecting mirror 48 of the present embodiment, the concave hole 46 has a tapered guide portion 84 for guiding the tip end portion of the optical fiber 12 to the fitting portion 54. Therefore, positioning and assembling of the tip portion of the optical fiber 12 with the point light source LED chip 82 are further facilitated.

  FIG. 12 is a view for explaining the configuration of a point light source LED chip 84 in another embodiment of the present invention, and corresponds to FIG. The point light source LED chip 84 of the present embodiment has the same configuration as that of FIGS. 1 and 2 except that the shape of the recessed hole 46 formed in the support layer 14 is different. That is, in the point light source LED chip 84, the second fitting portion 86 and the third fitting portion 88 having a larger diameter than the fitting portion 54 in the recessed hole 46 are sequentially provided concentrically. Is different.

  According to the point light source LED chip 84 provided with the reflecting mirror 48 of the present embodiment, the concave hole 46 has a fitting portion 54 having a different diameter in order to fit the tip portions of the plural types of optical fibers 12 having different diameters. Since the second fitting portion 86 and the third fitting portion 88 having a larger diameter are sequentially arranged on the side away from the one surface, the common point light source LED chip 84 is provided at the tip of the optical fiber 12 having a different diameter. Used to allow positioning and assembly.

  FIG. 13 is a view for explaining the configuration of a point light source LED chip 90 in another embodiment of the present invention, and corresponds to FIG. The point light source LED chip 90 of the present embodiment has the same configuration as that shown in FIGS. 1 and 2 except that the shape of the recessed hole 46 formed in the support layer 14 is different. That is, the point light source LED chip 90 has a tapered outer peripheral surface 92 concentrically provided on the outer peripheral surface of the support layer 14 formed in an annular shape around the light transmitting surface 42 so as to increase in diameter as it approaches the one surface. Is different.

  According to the point light source LED chip 90 provided with the reflecting mirror 48 of the present embodiment, the tapered outer peripheral surface 92 having a larger diameter as it approaches the one surface is provided on the outer peripheral surface of the support layer 14. The mechanical strength of the layer 14 is increased. Further, since the handling by the collet does not become an obstacle, the assemblability is further improved.

  As mentioned above, although one Example of this invention was described in detail with reference to drawings, this invention is not limited to those Examples, It can implement also in another aspect.

  For example, in the point light source LED chips 10, 72, 78, 82, 84, 90 of the above-described embodiment, the fitting portion 54 is formed in the recessed hole 46 formed in the support layer 14 following the reflecting mirror portion 50. Although the tapered fitting portion 80 and the like are formed according to various processes, only the reflecting mirror portion 50 may be formed in the concave hole 46 according to the same process.

  Further, the reflecting mirror part 50 formed in the concave hole 46 may be formed of a tapered surface having a diameter that becomes larger as it is separated from the one surface, that is, the light transmitting surface 42.

  In the above-described embodiment, the support layer 14 is formed in an annular shape around the light transmission surface 42 and has a smaller area than the upper surface of the main body portion 16, except for the vicinity of the bonding pad 35. The main body 16 may be fixed in the same area.

  In the above-described embodiment, the main body 16 of the point light source LED chips 10, 64, 72, 78, 82, 84, 90 may be of other types in the outer shape and the internal structure. For example, in the main body 16, the light emitting layer 24 having the quantum well structure is provided between the pair of multilayer reflective layers 20 and 28, and the first barrier layer 22, the active layer 24, and the second barrier layer 26 are quantum. Although the light emitting layer having the well structure is configured so that the multilayer film layer 28 forms a notch filter, the light emitting layer 24 may not have the quantum well structure, and both the multilayer film reflective layers 20 and 28 or one of the multilayer reflective layers 20 and 28 may be used. The multilayer film reflection layer 28 may be removed. Moreover, although the recessed part 40 was provided in the upper surface, the thing of the type in which the recessed part 40 is not provided may be sufficient. In this case, the light transmission surface 42 is flush with the upper surface of the current blocking layer 32.

  It should be noted that the above description is merely an embodiment, and other examples are not illustrated. However, the present invention is implemented in variously modified and improved modes based on the knowledge of those skilled in the art without departing from the gist of the present invention. Can do.

It is the figure seen from the one surface side which light outputs in the point light source LED chip which is one Example of this invention. It is a figure explaining the structure of the point light source LED chip of FIG. 1, and is II-II sectional view taken on the line in FIG. It is process drawing explaining the principal part of the manufacturing process of the point light source LED light-emitting chip of FIG.1 and FIG.2. It is a figure explaining the content of each process in the manufacturing process of FIG. It is the figure which showed an example of the relationship between the electric current applied to RC-LED (resonance cavity type light emitting diode) provided with the internal optical resonator which is a point light source LED chip like FIG. 1, and the directivity of output light. . It is process drawing for demonstrating the principal part of the manufacturing process of the point light source LED chip in the other Example of this invention, and is a figure equivalent to FIG. It is a figure explaining the content of each process in the manufacturing process of FIG. It is process drawing for demonstrating the principal part of the manufacturing process of the point light source LED chip in the other Example of this invention, and is a figure equivalent to FIG. It is a figure explaining the content of each process in the manufacturing process of FIG. It is sectional drawing for demonstrating the structure of the point light source LED chip in the other Example of this invention, and is a figure equivalent to FIG. It is sectional drawing for demonstrating the structure of the point light source LED chip in the other Example of this invention, and is a figure equivalent to FIG. It is sectional drawing for demonstrating the structure of the point light source LED chip in the other Example of this invention, and is a figure equivalent to FIG. It is sectional drawing for demonstrating the structure of the point light source LED chip in the other Example of this invention, and is a figure equivalent to FIG.

Explanation of symbols

10, 64, 72, 78, 82, 84, 90: Point light source LED chip (semiconductor light emitting chip)
14: Support layer 42: Light transmitting surface 46: Recess hole 48: Reflecting mirror 54: Fitting portion 62: Photosensitive resin (resist resin)
63: Light transmission mold 66: Gray scale mask 76: Resin sheet 80: Tapered fitting part (fitting part, tapered guide part)
84: Tapered guide

Claims (8)

A semiconductor light emitting chip in which a light transmitting surface from which light is output is locally provided on one surface,
A support layer formed of a photosensitive resin after curing, fixed on the one surface, and formed with a concave hole that optically exposes the light transmission surface to the bottom surface;
A reflecting mirror formed on the inner peripheral surface of the concave hole and reflecting light incident on the inner peripheral surface out of the light output from the light transmitting surface. Semiconductor light emitting chip.   2. The semiconductor light emitting chip having a reflecting mirror according to claim 1, wherein the support layer is formed by curing a photosensitive resin applied on the one surface.   The said support layer is hardened by the light which permeate | transmits this light transmissive shaping | molding die in the state in which the photosensitive resin apply | coated on the said surface was pressed by the light transmissive shaping | molding die. A semiconductor light emitting chip comprising two reflecting mirrors.   The support layer is characterized in that the photosensitive resin applied on the one surface is cured by light transmitted through a gray scale mask in which the light transmittance at the boundary of the exposure pattern changes continuously. A semiconductor light emitting chip comprising the reflecting mirror according to claim 2.   2. The semiconductor with a reflecting mirror according to claim 1, wherein the support layer is formed by molding and a resin sheet after the reflecting mirror is formed on the inner peripheral surface of the recessed hole is bonded onto the one surface. Light emitting chip.   6. The semiconductor light-emitting chip provided with the reflecting mirror according to claim 1, wherein the concave hole has an inner peripheral surface formed in a partial spherical shape or a partial parabolic shape.   The concave hole includes a reflecting mirror part in which the reflecting mirror is formed and one or more concentric with the reflecting mirror part in order to fit the tip of the optical fiber on the side away from the one surface of the reflecting mirror part. A semiconductor light-emitting chip comprising the reflecting mirror according to claim 1, further comprising a fitting portion.   8. The reflecting mirror according to claim 7, wherein the concave hole has a tapered guide portion for guiding the tip end portion of the optical fiber to the fitting portion on a side separated from the one surface of the fitting portion. Semiconductor light emitting chip provided.

Images