JP5266603B2 - Semiconductor light emitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor light emitting device capable of taking out light to the outside by highly efficiently exciting both front and rear surfaces of a wavelength conversion layer. <P>SOLUTION: The semiconductor light emitting device 10 is provided with: a substrate 20 having a recess having a reflection surface 22 formed therein; a mounting substrate 40 causing a semiconductor light emitting element 50 to be mounted so that a light emitting surface oppose the reflection surface 22, and fixed on the substrate 20; and the wavelength conversion layer 32 fixed on the substrate 20 or the mounting substrate 40, and arranged between the semiconductor light emitting element 50 and the reflection surface 22 so as to be away from the semiconductor light emitting element 50 and the reflection surface 22. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a semiconductor light emitting device, and more particularly to a semiconductor light emitting device that emits mixed color light of light from a semiconductor light emitting element and light from a wavelength conversion layer.

  Currently, semiconductor light-emitting devices that produce white light by combining part of the light from the blue light-emitting element with a phosphor and combining the light from the blue light-emitting element with the light from the phosphor are used in general lighting, street lights, and heads. It is used as a light source for lighting fixtures such as lamps.

As a conventional semiconductor light-emitting device of this type, Patent Document 1 discloses a light-emitting element, a main body having a reflective concave curved surface, and a main body with a simple configuration, in order to provide light with uniform color conversion efficiently and uniformly. The light emitting element has a light emitting surface facing the reflective concave surface, and a specific color light from the light emitting surface is reflected by the reflective concave curved surface, and is then formed into a film on the reflective concave curved surface. There has been disclosed a light emitting diode comprising a color light conversion resin film containing a phosphor for converting a part of specific color light to other color light.
JP 2001-230451 A

  Incidentally, in the semiconductor light emitting device disclosed in Patent Document 1, the phosphor layer is formed on the reflecting surface. For this reason, the proportion of light reflected by the reflective concave surface and reflected upward is very small, and the reflected light is only in the normal direction of the resin film. In this semiconductor light emitting device, the light reflected by the reflecting concave curved surface cannot be used efficiently.

  In addition, the distance between the light emitting element and the reflective concave curved surface needs to be separated by a certain distance or more due to the structure. Therefore, there has been a problem that the excitation light density from the light emitting element incident on the color light conversion resin film is reduced, and the light density in the light extraction direction is also reduced.

  In addition, the light emitting element is arranged in a hollow state using a lead frame, and when the light emitting element is driven with a large current, heat radiation is not sufficient from the lead frame alone.

  Further, since the light emitting element is arranged at the center position of the reflective concave curved surface, there is a problem that the light reflected by the reflective concave curved surface is shielded.

  The present invention has been made in view of such circumstances, and can provide a semiconductor light emitting device that can efficiently excite both the front surface and the back surface of the wavelength conversion layer and extract light to the outside.

In order to achieve the above object, a semiconductor light emitting device according to the present invention includes a substrate having a concave portion formed with a reflecting surface, and a plurality of semiconductor light emitting elements mounted so that the light emitting surface faces the reflecting surface, A mounting member fixed to a base body, and a wavelength conversion layer fixed to the base body or the mounting member and disposed between the semiconductor light emitting element and the reflecting surface so as to be separated from the semiconductor light emitting element and the reflecting surface. The mounting member is composed of a mounting substrate having an opening for extracting light, and the base is composed of a metal substrate, a ceramic substrate, or a semiconductor substrate, and the mounting member Is made of a highly heat-dissipating material capable of generating heat from the semiconductor light-emitting element, and is fixed so as to be in thermal contact with the periphery of the reflecting surface on the substrate. Formed on a metal mesh thermally embedded in an adhesive interface between the mounting member and the semiconductor light emitting element, the semiconductor light emitting element is located outside the opening and toward the center of the reflective surface of the base of the mounting member. The light is emitted from the semiconductor light emitting element so as to be obliquely incident on the wavelength conversion layer, and the opening is smaller than the size of the wavelength conversion layer.
Preferably, the wavelength conversion layer is formed at a central portion of the metal mesh.
Preferably, a mesh opening in which the wavelength conversion layer is not formed is provided in an outer peripheral portion of the metal mesh, and the element mounting portion is a primary excitation light emitted from the semiconductor light emitting element. The portion is incident on the surface of the wavelength conversion layer, and a part is formed at a position where the portion enters the reflection surface through the mesh opening .
Preferably, the mounting member is formed of a silicon substrate .
Preferably, a sealing layer made of a translucent resin is formed in a space formed by the base and the mounting member .

  According to the present invention, by disposing the wavelength conversion layer so as to be separated from the reflection surface, it is possible to efficiently excite both the front surface and the back surface of the wavelength conversion layer and extract light to the outside.

  According to the present invention, by disposing the wavelength conversion layer between the semiconductor light emitting element and the reflection surface so as to be separated from the reflection surface, both the front and back surfaces of the wavelength conversion layer are efficiently excited to the outside. A semiconductor light-emitting device that can extract light can be obtained.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The present invention will be described with reference to the following preferred embodiments, but can be modified in many ways without departing from the scope of the present invention, and other embodiments than the present embodiment can be utilized. be able to. Accordingly, all modifications within the scope of the present invention are included in the claims.

[First Embodiment]
FIG. 1 shows a first embodiment of a semiconductor light emitting device of the present invention.

  The semiconductor light emitting device 10 includes a substrate 20 having a recess formed with a reflection surface 22, a heat dissipation mesh 30 including a wavelength conversion layer 32 fixed to the substrate 20, and an element mounting portion 42 and a light extraction device fixed to the substrate 20. In a space formed by the mounting substrate 40 having the opening 44 for the semiconductor, the semiconductor light emitting element 50 mounted on the element mounting portion 42 so that the light emitting surface faces the reflecting surface 22, and the substrate 20 and the mounting substrate 40. The sealing layer 60 is filled.

  The substrate 20 is made of a material having high thermal conductivity, for example, a metal substrate such as copper or aluminum, a ceramic substrate such as aluminum oxide, silicon carbide, silicon nitride, or zirconium oxide, or a semiconductor substrate such as silicon.

  The substrate 20 is formed with a recess having a reflecting surface 22 in a parabolic shape. By making the reflecting surface 22 into a parabolic shape, light can be collected at the center of the reflecting surface 22, and efficient light extraction can be performed from the opening 44. If the substrate 20 is a highly reflective member, the recess can be used as it is as the reflecting surface 22. On the other hand, when the substrate 20 is made of a material having a low reflectance, a thin film having a high reflectance can be formed in the recess by metal deposition, plating, or the like to form the reflective surface 22.

  In the present embodiment, the shape of the recess is a paraboloid. However, the shape is not limited to this, and the shape can be a mortar shape or an elliptical shape.

  The mounting substrate 40 is made of a material having high heat dissipation, such as silicon, and is fixed so as to be in thermal contact with the periphery of the reflective surface 22 on the substrate 20 with a heat dissipation adhesive or the like. Here, thermal contact means that a heat path is formed between the mounting substrate 40 and the substrate 20. In addition to the case where the mounting substrate 40 and the substrate 20 are in direct contact, the case where an intermediate member is inserted between the mounting substrate 40 and the substrate 20 is also included. Since the semiconductor light emitting element is mounted on the mounting substrate having high heat dissipation, heat generated from the semiconductor light emitting element can be efficiently generated.

  In the present embodiment, an element mounting portion 42 that is substantially parallel to the substrate 20 is formed on the mounting substrate 40. As shown in FIG. 1, the mounting substrate 40 is inclined inwardly toward the center of the reflection surface 22 as it goes upward from the substrate 20. The mounting board 40 has an overhang shape at a predetermined height from the board 20 and further toward the center of the reflecting surface 22 and substantially parallel to the board 20. This overhanging portion becomes the element mounting portion 42. The mounting substrate 40 is further inclined outward from the element mounting portion 42 upward. Thereby, as shown in FIG. 1, an opening 44 for light extraction is formed in the mounting substrate 40 above the central portion of the reflecting surface 22.

  The semiconductor light emitting element 50 is mounted on the element mounting portion 42 via a bonding agent so that the light emitting surface thereof faces the reflecting surface 22. Since the element mounting portion 42 is located on the inner side from the periphery of the reflecting surface 22, the semiconductor light emitting element 50 is disposed in the vicinity of the peripheral portion of the reflecting surface 22. Thereby, the semiconductor light emitting element 50 can be prevented from covering the central portion of the reflecting surface 22.

  The semiconductor light emitting device 50 is, for example, a blue light emitting LED, and is configured by a semiconductor epitaxial layer having a light emitting portion composed of an InGaN-based semiconductor formed on a transparent substrate or an opaque substrate and these substrates. The number of semiconductor light emitting elements 50 and the like are determined as appropriate.

  The heat dissipation mesh 30 in which the wavelength conversion layer 32 is formed is thermally embedded in the adhesive interface between the substrate 20 and the mounting substrate 40. A heat path is formed so that heat generated in the wavelength conversion layer 32 is radiated to the substrate 20 and the mounting substrate 40 through the heat dissipation mesh 30.

  FIG. 2 shows a front view of the heat dissipating mesh 30 provided with the wavelength conversion layer 32 containing a phosphor. The heat radiating mesh 30 is made of a material having high thermal conductivity such as gold, aluminum, copper, and tungsten. As the phosphor, a YAG phosphor or a silicate phosphor is used. These phosphors are excited by blue light from a blue light emitting LED and emit yellow light. The blue light of the blue light emitting LED and the yellow light of the phosphor are combined to produce white light.

  In the present embodiment, the wavelength conversion layer 32 is formed at the center of the heat dissipation mesh 30. However, the wavelength conversion layer 32 may be formed on the entire surface of the heat dissipation mesh 30 without being limited thereto. The size of the wavelength conversion layer 32 is appropriately determined depending on the emission color required for the semiconductor light emitting device 10.

  The wavelength conversion layer 32 can be formed in the central portion of the heat dissipation mesh 30 by, for example, performing screen printing, stencil printing, or the like on the heat dissipation mesh 30 with a light-transmitting resin mixed with a predetermined concentration of phosphor.

  The sealing layer 60 is made of a translucent resin such as an epoxy resin or a silicone resin. In particular, a silicone resin is preferable from the viewpoints of heat resistance and thermal stress relaxation.

  Next, a method for manufacturing the semiconductor light emitting device 10 will be briefly described. First, a recess that becomes the reflection surface 22 is formed on the surface of the substrate 20 by wet or dry etching. If necessary, a highly reflective thin film can be formed in the recess by metal vapor deposition or plating.

  A silicon substrate is prepared as the mounting substrate 40, and the element mounting portion 42 is formed by anisotropic etching or the like. The semiconductor light emitting element 50 is mounted on the element mounting portion 42 by, for example, a flip chip method. A mounting substrate 40 on which the semiconductor light emitting element 50 is mounted is prepared in advance.

  Similar to the mounting substrate 40, a heat dissipation mesh 30 having a wavelength conversion layer 32 formed by screen printing, stencil printing or the like is prepared in advance.

  The heat dissipating mesh 30 is fixed so as to be in thermal contact with the substrate 20 via a heat dissipating adhesive or the like so as to separate the wavelength conversion layer 32 from the reflecting surface 22. Further, the mounting substrate 40 is fixed via a heat dissipating adhesive or the like so as to be in thermal contact with the heat dissipating mesh 30 and the substrate 20.

  Finally, a translucent resin is injected from the opening 44 to fill the space formed by the substrate 20 and the mounting substrate 40, and the sealing layer 60 is formed. At this time, liquid light-transmitting resin can be easily poured into the reflection surface 22 from the mesh opening of the outer periphery of the heat dissipation mesh 30 where the wavelength conversion layer 32 is not formed.

  Even when the wavelength conversion layer 32 is formed on the entire surface of the heat dissipation mesh 30, for example, after first injecting a translucent resin into the reflective surface 22 of the substrate 20, and then fixing the heat dissipation mesh 30 and the mounting substrate 40, The sealing layer 60 can be easily formed by injecting a translucent resin from the opening 44.

  Next, the operation of the semiconductor light emitting device 10 of the present embodiment will be described with reference to FIG.

  First, the light path will be described. Part of the blue light (hereinafter referred to as primary excitation light) emitted from the semiconductor light emitting element 50 made of a blue light emitting LED is incident on the surface of the wavelength conversion layer 32, and the others are the heat dissipation mesh 30 in which the wavelength conversion layer 32 is not formed. And is incident on the reflection surface 22.

  A portion of the primary excitation light incident on the surface of the wavelength conversion layer 32 is absorbed and wavelength-converted by a phosphor such as YAG: Ce contained in the wavelength conversion layer 32, and is primarily excited from the upper opening 44. It is extracted as reflected primary wavelength converted light (yellow light) having a wavelength longer than that of light. A portion of the primary excitation light incident on the surface of the wavelength conversion layer 32 is scattered by the phosphor of the wavelength conversion layer 32 and is extracted as reflected primary excitation light from the upper opening 44 without being wavelength-converted. Two dashed-dotted arrows heading from the wavelength conversion layer 32 toward the opening 44 schematically represent the reflected primary wavelength converted light and the reflected primary excitation light. A part of the primary excitation light passes through the wavelength conversion layer 32 and enters the reflection surface 22.

  On the other hand, the primary excitation light that has passed through the wavelength conversion layer 32 and the heat radiating mesh 30 and entered the reflection surface 22 is reflected upward by the reflection surface 22 to become secondary excitation light, and enters the back surface of the wavelength conversion layer 32. Part of the secondary excitation light wavelength-converted on the back surface passes through the wavelength conversion layer 32 and is extracted from the upper opening 44 as transmitted secondary wavelength-converted light. A part of the secondary excitation light is scattered by the phosphor of the wavelength conversion layer 32, and is extracted as transmitted secondary excitation light from the upper opening 44 without wavelength conversion. One dotted arrow heading from the wavelength conversion layer 32 toward the opening 44 schematically represents the transmitted secondary wavelength converted light and the transmitted secondary excitation light.

  In reality, the reflected primary excitation light, the reflected primary wavelength converted light, the transmitted secondary excitation light, and a part of the transmitted secondary wavelength conversion are reflected a plurality of times in the space formed by the mounting substrate 40 and the substrate 20, There is a case where it is finally taken out from the opening 44. These are referred to as transmitted secondary excitation light and transmitted secondary wavelength conversion.

  In the present invention, since the wavelength conversion layer 32 is disposed at a position separated from the reflection surface 22, a space is formed between the wavelength conversion layer 32 and the reflection surface 22. Due to the space, the reflected light from the reflecting surface 22 can be efficiently guided to the wavelength conversion layer 32, and the reflected light can be wavelength-converted effectively.

  Further, as shown in FIG. 1, by forming the opening 44 smaller than the size of the wavelength conversion layer 32, light can be collected and the light density can be improved. The size of the opening 44 can be formed to a desired size by performing anisotropic etching of the silicon substrate under appropriate conditions.

  In the present embodiment, the semiconductor light emitting element 50 is disposed in the vicinity of the peripheral edge of the heat dissipation mesh 30. Thereby, since the thing which shields light is not arrange | positioned in the center part of the reflective surface 22 with high light intensity, light can be taken out efficiently.

  Next, the heat path will be described. The heat generated from the semiconductor light emitting device 50 is transmitted to the silicon mounting substrate 40 having high thermal conductivity. Furthermore, it is transmitted to the substrate 20 with high heat dissipation that is in thermal contact. Heat generated from the phosphor contained in the wavelength conversion layer 32 is transmitted to the highly heat-dissipating substrate 20 through the metal heat dissipating mesh 30, and the phosphor does not store heat even if the intensity of the excitation light increases. . Furthermore, in the present invention, since the wavelength conversion layer 32 is disposed at a position separated from the reflecting surface 22, chromaticity can be adjusted using reflected light and transmitted light. In the phosphor layer formed adjacent to the reflecting surface shown in Patent Document 1 of the prior art, even if the concentration or thickness is changed, the contribution to wavelength conversion is mainly a constant surface layer portion, and the phosphor Since the inherent absorptance and reflectance become dominant, it only approaches a certain chromaticity, and it is extremely difficult to control the chromaticity. Since the support member that holds the wavelength conversion layer is in thermal contact with the mounting substrate and the substrate having high heat dissipation, heat generated from the wavelength conversion layer can be efficiently dissipated. Thereby, it can prevent that the efficiency of fluorescent substance falls and emitted light color changes, or the member of the periphery of a wavelength conversion layer deteriorates.

  In the present embodiment, the wavelength conversion layer 32 is formed on the heat dissipation mesh 30, but the wavelength conversion layer 32 may be a glass plate in which phosphors are dispersed.

  The wavelength conversion layer 32 may have any shape as long as it can be separated from the reflection surface 22.

[Second Embodiment]
FIG. 3 shows a second embodiment of the semiconductor light emitting device of the present invention. The same components as those of the semiconductor light emitting device shown in the first embodiment may be denoted by the same reference numerals and description thereof may be omitted.

  The semiconductor light emitting device 10 of the present embodiment includes a substrate 20 having a recess formed with a reflecting surface 22, a heat dissipation mesh 30 including a wavelength conversion layer 32 fixed to the substrate 20, and an element mounted. A space formed by the mounting substrate 40 having the portion 42 and the opening 44, the semiconductor light emitting element 50 mounted on the element mounting portion 42 so that the light emitting surface faces the reflecting surface 22, and the substrate 20 and the mounting substrate 40. And a sealing layer 60 filled in the container.

  The semiconductor light emitting device 10 of the present embodiment is inclined inwardly toward the center of the reflecting surface 22 as the element mounting portion 42 moves upward from the substrate 20. This is different from the semiconductor light emitting device 10 of the first embodiment including the element mounting portion 42 formed substantially parallel to the substrate 20 shown in FIG.

  In the present embodiment, the semiconductor light emitting element 50 is mounted on the element mounting portion 42 inclined inward, and the primary excitation light emitted from the semiconductor light emitting element 50 is incident on the wavelength conversion layer 32 obliquely. As a result, most of the wavelength conversion layer 32 can be excited, and the semiconductor light emitting device 10 with high utilization efficiency of the wavelength conversion layer 32 can be realized.

  Further, by adjusting the inclination of the element mounting portion 42 with respect to the substrate 20, most of the reflected primary excitation light and reflected primary wavelength converted light having strong light intensity can be guided to the opening 44. Furthermore, the semiconductor light emitting device 10 with high utilization efficiency is possible.

  According to the present embodiment, the element mounting portion 42 can be disposed at a position close to the substrate 20 with high heat dissipation, and heat generated from the semiconductor light emitting element 50 can be efficiently radiated through the substrate 20. .

  With respect to the light and heat paths, the same effect as in the first embodiment can be obtained.

[Third Embodiment]
FIG. 4 shows a third embodiment of the semiconductor light emitting device of the present invention. The same components as those in the semiconductor light emitting devices shown in the first embodiment and the second embodiment may be denoted by the same reference numerals and description thereof may be omitted.

  The semiconductor light emitting device 10 according to the present embodiment is fixed to the substrate 20, the substrate 20 having a recess having the reflective surface 22 formed thereon, the light transmissive substrate 70 including the wavelength conversion layer 72 embedded in the reflective surface 22, and the substrate 20. And a mounting substrate 40 having an element mounting portion 42 and an opening 44, a semiconductor light emitting element 50 mounted on the element mounting portion 42 so that the light emitting surface faces the reflection surface 22, and the substrate 20 and the mounting substrate 40. It is comprised from the sealing layer 60 with which the filled space was filled.

  In the semiconductor light emitting device 10 of the present embodiment, the wavelength conversion layer 72 is formed on the light transmissive substrate 70. This point is different from the semiconductor light emitting devices 10 of the first and second embodiments in which the wavelength conversion layer 32 shown in FIGS.

  The light transmissive substrate 70 is made of, for example, glass, quartz, sapphire, or the like. A wavelength conversion layer 72 containing a phosphor is formed at the center of the light transmissive substrate 70. As the phosphor, a YAG phosphor or a silicate phosphor is used. These phosphors are excited by blue light from a blue light emitting LED and emit yellow light. The blue light of the blue light emitting LED and the yellow light of the phosphor are combined to produce white light.

  In the present embodiment, as shown in FIG. 4, a light transmissive substrate 70 having a wavelength conversion layer 72 formed on the upper surface is embedded in the reflecting surface 22. Thereby, the wavelength conversion layer 72 is disposed so as to be separated from the reflection surface 22, and a space is formed between the wavelength conversion layer 72 and the reflection surface 22.

  Next, a method for forming the wavelength conversion layer 72 on the light transmissive substrate 70 will be described. First, a recess is formed on the upper surface of the light transmitting substrate 70 by wet or dry etching. Next, a mixture of a light transmissive resin and a phosphor is poured into the concave portion using a dispenser injection method, a stencil printing method, or the like, and the wavelength conversion layer 72 is formed by heat curing the light transmissive resin. The thickness of the wavelength conversion layer 72 is determined by the depth of the concave portion of the light transmissive substrate 70. In addition, the wavelength conversion layer 72 can be directly formed on the upper surface of the light transmissive substrate 70 by using a stencil printing method or the like without forming a recess in the light transmissive substrate 70.

  Next, a method for manufacturing the semiconductor light emitting device 10 of the present embodiment will be briefly described. First, a recess that becomes the reflection surface 22 is formed on the surface of the substrate 20 by wet or dry etching.

  The wavelength conversion layer 72 is formed on the light transmissive substrate 70 by the method described above. In addition, when forming the wavelength conversion layer 72, you may form a light reflection part (not shown) in the transparent substrate 70. FIG. First, a highly reflective metal thin film (for example, aluminum or silver) is formed on the entire surface of the light transmissive substrate 70 by vacuum deposition or sputtering. Next, at the same time as etching the recess for the wavelength conversion layer 72, the metal thin film on the upper surface of the light-transmitting substrate 70 is selectively removed. Thereby, a metal thin film is selectively formed on the side and bottom surfaces of the light-transmitting substrate 70.

  Next, a light transmissive substrate 70 having a wavelength conversion layer 72 on which a light reflecting portion is formed is embedded in the reflecting surface 22 of the substrate 20. Next, the mounting substrate 40 on which the semiconductor light emitting element 50 is mounted is fixed so as to be in thermal contact with the substrate 20 with a heat dissipating adhesive (not shown) or the like.

  Finally, a translucent resin is injected from the opening 44 to fill the space formed by the substrate 20 and the mounting substrate 40, and the sealing layer 60 is formed.

  In the above manufacturing method, the case where the light reflecting portion is formed on the light transmissive substrate 70 has been described. As another manufacturing method of the light reflecting portion, when the light transmissive substrate 70 on which the wavelength conversion layer 72 is formed is embedded in the reflecting surface 22 of the substrate 20, a white adhesive (for example, silica, titania) having a high light reflectance. The light-reflecting portion can be formed by adhering the light-transmitting substrate 70 and the reflecting surface 22 to each other with a filler such as alumina mixed therein. In particular, the use of a highly heat-dissipating adhesive with high alumina filling is more effective for heat dissipation of the wavelength conversion layer 72.

  Next, the operation of the semiconductor light emitting device 10 of the present embodiment will be described with reference to FIG.

  First, the light path will be described. A part of the blue light (hereinafter referred to as primary excitation light) emitted from the semiconductor light emitting element 50 made of a blue light emitting LED is incident on the surface of the wavelength conversion layer 72, and the other is a light transmittance in which the wavelength conversion layer 72 is not formed. The light passes through the peripheral edge of the substrate 70 and enters the reflecting surface 22.

  A portion of the primary excitation light incident on the surface of the wavelength conversion layer 72 is absorbed and wavelength-converted by a phosphor such as YAG: Ce contained in the wavelength conversion layer 72, and is primarily excited from the upper opening 44. It is extracted as reflected primary wavelength converted light (yellow light) having a wavelength longer than that of light. Part of the primary excitation light incident on the surface of the wavelength conversion layer 72 is scattered by the phosphor of the wavelength conversion layer 72 and is extracted as reflected primary excitation light from the upper opening 44 without being wavelength-converted. Two dashed-dotted arrows from the wavelength conversion layer 72 toward the opening 44 schematically represent the reflected primary wavelength converted light and the reflected primary excitation light. A part of the primary excitation light passes through the wavelength conversion layer 72 and enters the reflection surface 22.

  On the other hand, the primary excitation light that has passed through the wavelength conversion layer 72 and the light transmissive substrate 70 and entered the reflection surface 22 is reflected a plurality of times by the reflection surface 22 and becomes secondary excitation light, which is incident on the back surface of the wavelength conversion layer 72. To do. Part of the secondary excitation light wavelength-converted on the back surface passes through the wavelength conversion layer 72 and is extracted from the upper opening 44 as transmitted secondary wavelength-converted light. Part of the secondary excitation light is scattered by the phosphor of the wavelength conversion layer 72, and is extracted as transmitted secondary excitation light from the upper opening 44 without being wavelength-converted. One dotted arrow heading from the wavelength conversion layer 72 toward the opening 44 schematically represents the transmitted secondary wavelength converted light and the transmitted secondary excitation light.

  In the present invention, since the wavelength conversion layer 72 is disposed at a position separated from the reflection surface 22, a space is formed between the wavelength conversion layer 72 and the reflection surface 22. Due to the space, the reflected light from the reflecting surface can be efficiently guided to the wavelength conversion layer, and the reflected light can be effectively wavelength-converted.

  Further, as shown in FIG. 4, by forming the opening 44 smaller than the size of the wavelength conversion layer 32, it is possible to condense light and to improve the light density. The size of the opening 44 can be formed to a desired size by performing anisotropic etching of the silicon substrate under appropriate conditions.

  In the present embodiment, the semiconductor light emitting element 50 is disposed in the vicinity of the peripheral edge of the light transmissive substrate 70. Thereby, since the thing which shields light is not arrange | positioned in the center part of the reflective surface 22 with high light intensity, light can be taken out efficiently.

  Next, the heat path will be described. The heat generated from the semiconductor light emitting device 50 is transmitted to the silicon mounting substrate 40 having high thermal conductivity. Furthermore, it is transmitted to the substrate 20 with high heat dissipation that is in thermal contact. Heat generated from the phosphor contained in the wavelength conversion layer 72 is transmitted to the highly heat-radiating substrate 20 through, for example, a glass light-transmitting substrate 70, and the phosphor stores heat even when the intensity of the excitation light increases. Not to do. Thereby, it can prevent that the efficiency of fluorescent substance falls and emitted light color changes, or the member of the periphery of a wavelength conversion layer deteriorates.

  The present invention is not limited to the above-described embodiments, and many modifications are possible based on the above description.

1 is a schematic configuration diagram showing a semiconductor light emitting device according to a first embodiment. The schematic block diagram which shows the thermal radiation mesh used for 1st Embodiment Schematic configuration diagram showing a semiconductor light emitting device according to a second embodiment Schematic configuration diagram showing a semiconductor light emitting device according to a third embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Semiconductor light-emitting device, 20 ... Board | substrate, 22 ... Reflecting surface, 30 ... Radiation mesh, 32 ... Wavelength conversion layer, 40 ... Mounting substrate, 42 ... Element mounting part, 44 ... Opening part, 50 ... Semiconductor light-emitting element, 60 ... Sealing layer, 70 ... light transmissive substrate, 72 ... wavelength conversion layer

Claims (5)

A substrate having a recess formed with a reflective surface;
A plurality of semiconductor light emitting elements are mounted such that the light emitting surface faces the reflecting surface, and a mounting member fixed to the base body,
A wavelength conversion layer fixed to the base body or the mounting member, and disposed between the semiconductor light emitting element and the reflective surface and spaced apart from the semiconductor light emitting element and the reflective surface;
A semiconductor light emitting device comprising :
The mounting member is composed of a mounting substrate having an opening for extracting light,
The base is composed of a metal substrate, a ceramic substrate or a semiconductor substrate,
The mounting member is made of a highly heat-dissipating material capable of generating heat from the semiconductor light emitting element, and is fixed so as to be in thermal contact with the periphery of the reflective surface on the base,
The wavelength conversion layer is formed on a metal mesh thermally embedded in an adhesive interface between the base and the mounting member,
The semiconductor light emitting element is mounted on an element mounting portion that is outside the opening and is inclined inward toward the center of the reflecting surface of the base of the mounting member, and light emitted from the semiconductor light emitting element is Arranged to enter the wavelength conversion layer at an angle,
The opening is smaller than the size of the wavelength conversion layer;
Semiconductor light emitting device. The semiconductor light emitting device according to claim 1, wherein the wavelength conversion layer is formed at a central portion of the metal mesh . A mesh opening that does not form the wavelength conversion layer is provided on the outer periphery of the metal mesh ,
The element mounting portion is located at a position where a part of the primary excitation light emitted from the semiconductor light emitting element is incident on the surface of the wavelength conversion layer and a part is incident on the reflecting surface through the mesh opening. The semiconductor light-emitting device according to claim 2 formed . The semiconductor light-emitting device according to claim 1, wherein the mounting member is formed of a silicon substrate . The semiconductor light-emitting device according to claim 1, wherein a sealing layer made of a translucent resin is formed in a space formed by the base and the mounting member .

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