JP2012069552A - Semiconductor light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor light-emitting device capable of improving extraction efficiency of light and capable of preventing temporal variation in optical characteristics.SOLUTION: A semiconductor light-emitting device comprises: a semiconductor light-emitting element 3 having a base 2, a first electrode 9 provided on a first surface, and a second electrode 10 provided on a second surface opposite to the first surface; and a junction portion 4 provided between the base and the second electrode. The junction portion has a resin portion. Conductors having conductivity and reflectors reflecting light emitted from the semiconductor light-emitting element are dispersed in the resin portion.

Description

  Embodiments described herein relate generally to a semiconductor light emitting device.

2. Description of the Related Art A semiconductor light emitting device in which a semiconductor light emitting element is bonded to a substrate using a conductive adhesive containing silver is known. In such a semiconductor light emitting device, the light emitted from the semiconductor light emitting element is reflected by the silver contained in the conductive bonding agent, and a part thereof is directed to the outside from the surface opposite to the bonding side of the semiconductor light emitting element. Are emitted.
However, although silver contained in the conductive bonding agent can be said to have high light reflectance as a conductive material, it is absolutely low in light reflectance. For this reason, the light extraction efficiency may be reduced.
In addition, when silver reflection is used, there is a possibility that optical characteristics such as light reflectivity will change over time due to silver sulfide.

JP 2004-39983 A

  Embodiments of the present invention provide a semiconductor light-emitting device that can improve the light extraction efficiency and suppress temporal fluctuations in optical characteristics.

  According to the embodiment, a semiconductor having a base, a first electrode provided on a first surface, and a second electrode provided on a second surface opposite to the first surface A light emitting element, a base portion, and a joint portion provided between the second electrode, the joint portion including a resin portion, a conductive conductor, and the semiconductor light emitting device. There is provided a semiconductor light emitting device characterized in that a reflector for reflecting light emitted from an element is dispersed in the resin portion.

(A) is a schematic top view of the semiconductor light-emitting device concerning 1st Embodiment, (b) is the sectional view on the AA line in (a). It is a model enlarged view of the B section in FIG.1 (b). It is a schematic graph for demonstrating the relationship between the volume resistivity of a conductor, and resistance value. It is a graph for demonstrating the light reflectivity of a reflector. It is a schematic graph for demonstrating the improvement of a light reflectance. It is a schematic graph for demonstrating a time-dependent change of a light reflectance. FIG. 6 is a schematic cross-sectional view illustrating a semiconductor light emitting device according to a second embodiment. It is a schematic diagram for illustrating about the magnitude | size of a conductor and the magnitude | size of a reflector. FIG. 6 is a schematic cross-sectional view illustrating a semiconductor light emitting device according to a third embodiment.

Hereinafter, embodiments will be illustrated with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.
[First embodiment]
FIG. 1 is a schematic cross-sectional view illustrating the semiconductor light emitting device according to the first embodiment. 1A is a schematic plan view of the semiconductor light emitting device according to the first embodiment, and FIG. 1B is a cross-sectional view taken along line AA in FIG.
FIG. 2 is a schematic enlarged view of a portion B in FIG.
As shown in FIG. 1, the semiconductor light emitting device 1 includes a base portion 2, a semiconductor light emitting element 3, a joint portion 4, a base portion 11, and a wiring portion 12.

The base 2 is provided with a substrate 5 and a conductive film 6 formed so as to cover the surface of the substrate 5.
The board | substrate 5 can be made into the plate-shaped body about 200 micrometers thick formed from copper, for example. However, it is not necessarily limited to this and can be changed as appropriate. For example, the board | substrate 5 can also be formed from metals, such as a copper alloy, an iron alloy, and aluminum. In addition, the substrate 5 may be formed of a conductive material powder containing a conductive material such as gold, silver, copper, or the like so as to have conductivity.

The conductive film 6 can be a film-like body made of silver and having a thickness of about 2 μm to 10 μm, for example. However, it is not necessarily limited to this and can be changed as appropriate. For example, the conductive film 6 may be formed of a metal such as a silver alloy (for example, an alloy of rhodium or palladium and silver), gold, a gold-silver alloy, palladium, platinum, or molybdenum.
The conductive film 6 can be formed using a plating method such as electrolytic plating. However, the conductive film 6 is not limited to the one formed using a plating method, and may be formed using a film forming method such as a sputtering method, for example.

  Further, the base 2 is not limited to one formed only from a conductive material. For example, an insulating substrate (for example, a glass epoxy substrate (FR-4, CEM-3) provided with electrical wiring (not shown) is used. Etc.), ceramic substrates, silicon substrates, glass substrates, etc.) and flexible printed circuits (FPC). In this case, the electrical wiring (not shown) can be, for example, a copper wiring.

The semiconductor light emitting element 3 is provided with a light emitting layer 7, a substrate 8, an electrode 9 (first electrode), and an electrode 10 (second electrode).
The light emitting layer 7 may have a quantum well structure including a well layer that generates light by recombination of holes and electrons, and a barrier layer (clad layer) having a larger band gap than the well layer. it can.
In this case, a single quantum well (SQW) structure or a multiple quantum well (MQW) structure may be used. A plurality of single quantum well structures may be stacked.

For example, as a single quantum well structure, a barrier layer made of GaN (gallium nitride), a well layer made of InGaN (indium gallium nitride), and a barrier layer made of GaN (gallium nitride) are stacked in this order. Can be illustrated.
As the multi-quantum well structure, a barrier layer made of GaN (gallium nitride), a well layer made of InGaN (indium gallium nitride), a barrier layer made of GaN (gallium nitride), a well layer made of InGaN (indium gallium nitride) An example in which barrier layers made of GaN (gallium nitride) are stacked in this order can be exemplified.
The light emitting layer 7 is not limited to the quantum well structure, and a structure capable of emitting light can be selected as appropriate.

  A light emitting layer 7 is formed on one main surface of the substrate 8 by crystal growth. In this case, the substrate 8 is preferably made of the same material as that for crystal growth, or made of a material having a lattice constant and a thermal expansion coefficient close to those for crystal growth. However, when the crystal growth is made of a nitride semiconductor, it is difficult to form a base 8 having an appropriate size made of a nitride semiconductor. Therefore, the substrate 8 can be made of SiC, spinel, or the like.

The electrode 9 is provided on the surface (first surface) of the semiconductor light emitting element 3. That is, the electrode 9 is provided on the surface of the light emitting layer 7 opposite to the side provided on the substrate 8.
The electrode 9 can be made of, for example, gold.
The electrode 10 is provided on the surface (second surface) opposite to the surface of the semiconductor light emitting element 3. That is, the electrode 10 is provided on the surface of the base 8 opposite to the side on which the light emitting layer 7 is provided.
The electrode 10 may be a triple layer of Ti (titanium) / Ni (nickel) / Au (gold).
However, the materials and the number of layers of the electrode 9 and the electrode 10 are not limited to those illustrated, and can be changed as appropriate.
The electrode 9 can be an anode electrode, and the electrode 10 can be a cathode electrode.
By arranging the electrode 9 and the electrode 10 in this way, a current can flow in the thickness direction of the semiconductor light emitting element 3.

Here, the shape and dimension of each element provided in the semiconductor light emitting element 3 are illustrated.
The light emitting layer 7 can have a square shape with a side of about 550 μm.
The base 8 can have a square shape with a side of about 600 μm and a thickness of about 150 μm.
The electrode 9 can have a circular shape with a diameter of about 100 μm and a thickness of about 1000 mm.
The electrode 10 is formed so as to cover the main surface of the substrate 8, and the thickness of Ti (titanium) can be about 1000 mm, the thickness of Ni (nickel) can be about 2000 mm, and the thickness of Au (gold) can be about 1000 mm. .
However, the shapes, dimensions, and the like of the light emitting layer 7, the base 8, the electrode 9, and the electrode 10 are not limited to those illustrated, and can be appropriately changed.

The base 11 is provided separately from the base 2. The base 11 is provided with a substrate 15 and a conductive film 16 formed so as to cover the surface of the substrate 15.
In this case, the substrate 15 can be the same as the substrate 5 described above. The conductive film 16 can be the same as the conductive film 6 described above. Therefore, the detailed description regarding the base 11 is omitted.
The wiring part 12 electrically connects the base part 11 and the electrode 9. For example, the wiring portion 12 may be a gold wire having a diameter of about 20 μm.

The joint portion 4 is provided between the base portion 2 and the electrode 10.
In the semiconductor light emitting device 1 according to the present embodiment, a current flows in the thickness direction of the semiconductor light emitting element 3 via the junction 4.
In addition, the light emitted from the semiconductor light emitting element 3 to the base 2 side is reflected inside the joint 4 so that the light can be extracted to the outside.
Therefore, as shown in FIG. 2, the bonding portion 4 includes a resin portion 17, and a conductive portion 18 having conductivity and a reflector 19 that reflects light emitted from the semiconductor light emitting element 3 are connected to the resin portion 17. Dispersed in.
That is, the junction 4 has the conductor 18 so that the electrode 10 of the semiconductor light emitting element 3 and the base 2 can be electrically connected.
Moreover, the junction part 4 has the reflector 19 so that the light emitted from the semiconductor light emitting element 3 toward the base part 2 can be reflected and extracted to the outside.
And since the junction part 4 has the resin part 17, the semiconductor light-emitting device 3 and the base 2 can be mechanically joined now.

  The joint 4 protrudes from the periphery of the base 8 by about 150 μm. Further, in order to ensure the bonding strength, the portion protruding from the peripheral edge of the base 8 covers up to a position about 1/3 to 2/3 of the thickness of the base 8. The thickness of the joint portion 4 between the electrode 10 and the base portion 2 can be about 2 μm to 10 μm.

  The resin part 17 can be formed of, for example, an epoxy resin, a silicone resin, or a mixture of an epoxy resin and a silicone resin. However, the resin forming the resin portion 17 is not limited to the illustrated one, and can be changed as appropriate. In this case, it is preferable that the resin forming the resin portion 17 can be supplied in a liquid state and can be cured by being held in an atmosphere of 200 ° C. or lower. If it is such, the mechanical joining of the semiconductor light emitting element 3 and the base 2 can be facilitated.

For example, the conductor 18 may have a scale shape, a flat shape, or the like. The average dimension of the longest portion of the conductor 18 can be about 2 μm to 3 μm. The conductor 18 may be formed of silver, gold, copper, platinum, nickel, iron, zinc, ruthenium, rhodium, palladium, indium, or an alloy thereof.
In this case, a conductor formed from the same material may be included in the joint 4, or a plurality of types of conductors formed from different materials may be included in the joint 4.
Note that the shape, dimensions, and material of the conductor 18 are not limited to those illustrated, but can be changed as appropriate.

The volume ratio of the conductor 18 in the resin part 17 can be 40% or more and 90% or less.
FIG. 3 is a schematic graph for illustrating the relationship between the volume resistivity and the resistance value of the conductor. As shown in FIG. 3, if the volume ratio of the conductor 18 is 40% or more, sufficient electrical conductivity can be ensured.

  Moreover, if the volume resistivity of the conductor 18 is 90% or less, the volume for including the reflector 19 can be secured.

For example, the reflector 19 may have a scale shape, a flat shape, or the like. The average dimension of the longest portion of the reflector 19 can be about 1 μm.
The light reflectance of the reflector 19 with respect to the light emitted from the semiconductor light emitting element 3 is preferably 85% or more. By doing so, the light extraction efficiency can be improved.
In addition, the light reflectance in this specification is the light reflectance (light reflectance of the reflector 19 before including in the junction part 4) in the reflector 19 single-piece | unit. Further, the light reflectance in the present specification is for light emitted from the semiconductor light emitting element 3 or light having a longer wavelength than light emitted from the semiconductor light emitting element 3.
FIG. 4 is a graph for illustrating the light reflectance of the reflector.
FIG. 4 illustrates the case where the reflector is titanium dioxide (TiO ₂ ) as an example.
As shown in FIG. 4, when the reflector is made of titanium dioxide (TiO ₂ ), sufficient light reflectance can be secured for light having a wavelength exceeding 400 nm.

The reflector is not limited to titanium dioxide (TiO ₂ ).

Moreover, it is preferable that the reflector 19 has a small change in light reflectance with time.
Examples of such a reflector 19 include those formed from white pigments. Examples of white pigments include zinc oxide (ZnO), barium sulfate (BaSO ₄ ), titanium dioxide (TiO ₂ ), boron nitride (BrN), magnesium oxide (MgO), calcium carbonate (CaCO ₃ ), and alumina (Al ₂ O _3). ), Barium oxide (BaO), zirconia (ZrO ₂ ), and the like. However, the white pigment is not limited to those illustrated, and can be appropriately changed.

  If a white resin made of an organic material or the like is used, the surface of the white resin may be altered by the light emitted from the semiconductor light emitting element 3, and the light reflectance of the white resin may change with time. Therefore, it is preferable to use a white pigment made of an inorganic material.

In this case, the reflector 19 formed from the same material may be included in the joint 4, or a plurality of types of reflectors 19 formed from different materials may be included in the joint 4. .
The shape, dimensions, and material of the reflector 19 are not limited to those illustrated, but can be changed as appropriate.

  The volume ratio of the reflector 19 in the resin part 17 can be 5% or more and 40% or less. If the volume ratio of the reflector 19 is 5% or more and 40% or less, the light extraction efficiency can be improved.

Here, the size of the reflector 19 is preferably smaller than the size of the conductor 18. This is because if the size of the reflector 19 is smaller than the size of the conductor 18, it is easy to ensure conduction even if the reflector 19 enters between the conductors 18.
The volume ratio of the reflector 19 is preferably smaller than the volume ratio of the conductor 18. This is because if the volume ratio of the reflector 19 is less than the volume ratio of the conductor 18, it is easy to ensure conduction even if the reflector 19 enters between the conductors 18.

Next, the effect when the reflector 19 is included in the joint portion 4 will be illustrated.
FIG. 5 is a schematic graph for illustrating an improvement in light reflectance.
In addition, C in FIG. 5 is the case of the spherical conductor 18 formed from silver, and D is the case of the scale-like conductor 18 formed from silver.
Moreover, E in FIG. 5 is the case of the spherical reflector 19 formed from a white pigment.

As indicated by C and D in FIG. 5, it can be said that silver has a high light reflectance as a conductive material. Therefore, the light reflectance can be increased only by including the conductor 18 formed of silver in the joint portion 4.
However, as shown by E in FIG. 5, the reflector 19 formed from a white pigment has a higher light reflectance. Therefore, if the reflector 19 made of a white pigment is further included in the joint portion 4, the light reflectance can be further increased. In this case, if the light reflectance can be increased, the amount of light absorbed inside the joint 4 can be reduced, so that the light extraction efficiency can be improved.

FIG. 6 is a schematic graph for illustrating the change in light reflectance with time.
In addition, F and G in FIG. 6 are cases of the conductor 18 formed from silver. F is a case where light having a wavelength of 570 nm is irradiated, and G is a case where light having a wavelength of 460 nm is irradiated. H and I are the cases of the reflector 19 formed from a white pigment. H is when light having a wavelength of 570 nm is irradiated, and I is when light having a wavelength of 460 nm is irradiated.
When the silver is irradiated with light, the silver is sulfided inside the joint 4. For this reason, silver sulfidation progresses as the irradiation time becomes longer, so that the light reflectance of the conductor 18 decreases as shown by F and G in FIG.
On the other hand, the white pigment has very little alteration due to light irradiation. Therefore, as shown to H and I in FIG. 6, it can suppress that the light reflectivity of the reflector 19 falls even if irradiation time becomes long.

According to the present embodiment, since the conductor 18 and the reflector 19 are included in the joint portion 4, a current can flow in the thickness direction of the semiconductor light emitting element 3, and the base portion 2 extends from the semiconductor light emitting element 3. The light emitted to the side can be reflected inside the joint 4.
Moreover, since the reflector 19 is formed of a white pigment, it is possible to suppress a change in light reflectance with time at the joint 4. Therefore, it is possible to suppress the temporal variation of the optical characteristics of the semiconductor light emitting device.

[Second Embodiment]
FIG. 7 is a schematic cross-sectional view illustrating a semiconductor light emitting device according to the second embodiment.

FIG. 7 schematically shows a cross section of the joint 4a as in the case of FIG.
In addition, since each element other than the junction part 4a provided in a semiconductor light-emitting device can be made to be the same as that illustrated in FIG. 1, their illustration and description are omitted.
As shown in FIG. 7, the bonding portion 4 a includes a resin portion 17, and a conductive conductor 18 a and a reflector 19 a that reflects light emitted from the semiconductor light emitting element 3 are provided in the resin portion 17. Distributed.

That is, the junction 4a has the conductor 18a, so that the electrode 10 of the semiconductor light emitting element 3 and the base 2 can be electrically connected.
Further, the joint 4a includes the reflector 19a, so that the light emitted from the semiconductor light emitting element 3 toward the base 2 can be reflected and extracted to the outside.
And since the junction part 4a has the resin part 17, it can join the semiconductor light-emitting device 3 and the base 2 mechanically.

  The joint portion 4 a extends from the periphery of the base 8 by about 150 μm. Further, in order to ensure the bonding strength, the portion protruding from the peripheral edge of the base 8 covers up to a position about 1/3 to 2/3 of the thickness of the base 8. The thickness of the joint portion 4a between the electrode 10 and the base portion 2 can be about 2 μm to 10 μm.

The conductor 18a has a spherical shape. If the conductor 18a has a spherical shape, a gap is easily formed between the conductors 18a, and the reflector 19a can be easily mixed.
The average diameter of the conductor 18a can be about 2 μm to 3 μm. The conductor 18a can be formed of silver, gold, copper, platinum, nickel, iron, zinc, ruthenium, rhodium, palladium, indium, or an alloy thereof.
In this case, a conductor formed from the same material may be included in the joint 4a, or a plurality of types of conductors formed from different materials may be included in the joint 4a.
In addition, the dimension and material of the conductor 18a are not necessarily limited to what was illustrated, and can be changed suitably.

  The volume ratio of the conductor 18a can be 40% or more and 90% or less.

As illustrated in FIG. 3, if the volume ratio of the conductor 18a is 40% or more, sufficient electric conductivity can be ensured.
Further, if the volume resistivity of the conductor 18a is 90% or less, a volume for including the reflector 19 can be secured.

The reflector 19a has a spherical shape.
The light reflectance of the reflector 19a is preferably 85% or more. By doing so, the light extraction efficiency can be improved.

Moreover, it is preferable that the reflector 19a has little change in light reflectance with time.
As such a reflector 19a, the thing formed from the material similar to the case of the reflector 19 mentioned above can be illustrated. For example, the reflector 19a can be formed from a white pigment.

In this case, the reflector 19a formed from the same material may be included in the joint 4a, or a plurality of types of reflectors 19a formed from different materials may be included in the joint 4a. .
In addition, the dimension and material of the reflector 19a are not necessarily limited to what was illustrated, and can be changed suitably.

  The volume ratio of the reflector 19a can be 5% or more and 40% or less. If the volume ratio of the reflector 19a is 5% or more and 40% or less, the light extraction efficiency can be improved.

Here, the size of the reflector 19a is preferably smaller than the size of the conductor 18a. This is because if the size of the reflector 19a is smaller than the size of the conductor 18a, it is easy to ensure conduction even if the reflector 19a enters between the conductors 18a.
Further, the volume ratio of the reflector 19a is preferably smaller than the volume ratio of the conductor 18a. This is because if the volume ratio of the reflector 19a is smaller than the volume ratio of the conductor 18a, it is easy to ensure conduction even if the reflector 19a enters between the conductors 18a.

Next, the size of the conductor 18a and the size of the reflector 19a will be further illustrated. The spheres with the same radius can be packed most closely when the spheres are arranged on the face of the cube (face-centered cubic lattice).
Therefore, if the reflector 19a has such a size that can enter a gap generated between the conductors 18a arranged at the center of the cube, the contact between the conductors 18a is prevented from being hindered. be able to.

そのため、導電体１８ａの半径Ｒと、反射体１９ａの半径ｒとが以下の（２）式に表すような関係となるようにすれば、導電体１８ａ同士の間に生ずる隙間に反射体１９ａが入り込めることになる。すなわち、導電体１８ａ同士の間に反射体１９ａが入り込んだとしても、導電体１８ａ同士の間における接触が阻害されることを抑制することができる。
また、反射体１９ａが小さい表面積を有し、分散しやすいものとなる。 FIG. 8 is a schematic diagram for illustrating the size of the conductor 18a and the size of the reflector 19a. FIG. 8 exemplifies the contact state of one surface of the cube of the conductor 18a arranged at the center of the cube.
As shown in FIG. 8, if the radius of the conductor 18a is R, the gap generated between the conductors 18a can be expressed by the following equation (1).

Therefore, if the radius R of the conductor 18a and the radius r of the reflector 19a are set to have a relationship represented by the following formula (2), the reflector 19a is formed in a gap generated between the conductors 18a. It will get in. That is, even if the reflector 19a enters between the conductors 18a, it is possible to prevent the contact between the conductors 18a from being inhibited.
Further, the reflector 19a has a small surface area and is easily dispersed.

本実施の形態によれば、接合部４ａに導電体１８ａと反射体１９ａとを含ませているので、半導体発光素子３の厚み方向に電流を流すことができるとともに、半導体発光素子３から基部２の側に出射した光を接合部４ａの内部において反射させることができる。
また、反射体１９ａが白色顔料から形成されているので、接合部４ａにおける光反射率の経時変化を抑制することができる。そのため、半導体発光装置の光学特性の経時的な変動を抑制することができる。

According to the present embodiment, since the conductor 18a and the reflector 19a are included in the joint 4a, a current can flow in the thickness direction of the semiconductor light emitting element 3, and the base 2 The light emitted to the side can be reflected inside the joint 4a.
Moreover, since the reflector 19a is formed of a white pigment, it is possible to suppress a change with time in the light reflectance at the joint 4a. Therefore, it is possible to suppress the temporal variation of the optical characteristics of the semiconductor light emitting device.

  Further, if the radius R of the conductor 18a and the radius r of the reflector 19a are in the relationship expressed by the above-described equation (2), the contact between the conductors 18a is inhibited. Can be suppressed.

In addition, the combination of the shape of a conductor and the shape of a reflector is not necessarily limited to what was mentioned above, It can also be set as the combination illustrated below.
For example, the conductor may have a scale shape, and the reflector may have a spherical shape. In this way, since the number of contact points between the conductors can be increased, the electrical conductivity can be improved. In addition, the reflector has a small surface area and can be easily dispersed.
Further, for example, the conductor may have a spherical shape, and the reflector may have a non-spherical shape.
The non-spherical shape includes, for example, those having a distorted shape in addition to the scale shape and the flat shape described above.
In this way, it becomes easy to form a gap between the conductors, so it is easy to mix the reflectors. Moreover, since the surface area with respect to the unit volume of a reflector can be increased, a light reflection characteristic can be improved.
In addition, for example, the conductor may have a scale shape, and the reflector may have an aspheric shape.
In this way, since the number of contact points between the conductors can be increased, the electrical conductivity can be improved. Moreover, since the surface area with respect to the unit volume of a reflector can be increased, a light reflection characteristic can be improved.

[Third embodiment]
FIG. 9 is a schematic cross-sectional view illustrating a semiconductor light emitting device according to the third embodiment.
As shown in FIG. 9, the semiconductor light emitting device 1 a includes a base portion 2, a semiconductor light emitting element 3, a junction portion 4, a base portion 11, and a wiring portion 12 in the same manner as illustrated in FIG. 1. Furthermore, a reflection unit 20 and a wavelength conversion unit 21 are provided.

The reflection unit 20 is provided so as to surround the periphery of the wavelength conversion unit 21.
The reflection unit 20 diffuses the light emitted from the semiconductor light emitting element 3 into the wavelength conversion unit 21 and emits the light toward the front side of the semiconductor light emitting device 1a.
In order to easily reflect the light emitted from the semiconductor light emitting element 3, the reflectance of the reflecting portion 20 can be set to 90% or more in a wavelength region of 380 nm to 720 nm, for example.

Examples of the material for forming the reflective portion 20 include polyphthalamide resin (PPA) and silicone resin. Further, a reflective film (for example, a metal thin film) made of a material having a high light reflectivity may be provided on the surface of the reflective portion 20.
However, it is not necessarily limited to these illustrated materials, and can be appropriately changed.

A reflection surface (a surface on the wavelength conversion unit 21 side) 20a of the reflection unit 20 is inclined in a direction in which the emission side tip is separated from the central axis of the semiconductor light emitting device 1a. Therefore, the light emitted from the semiconductor light emitting element 3 can be diffused into the wavelength conversion unit 21 and the light can be efficiently emitted toward the front side of the semiconductor light emitting device 1a.
The base 2 and the base 11 are provided so as to penetrate the reflection part 20. A leg 2a for mounting on a substrate or the like is provided at the end of the base 2. A leg 11a for mounting on a substrate or the like is provided at the end of the base 11.

The wavelength conversion unit 21 is provided so as to cover the semiconductor light emitting element 3, the bonding unit 4, the wiring unit 12, the reflection surface 20 a of the reflection unit 20, and the like.
The wavelength conversion unit 21 can be formed from a resin in which phosphors capable of wavelength conversion are dispersed.
A fluorescent substance can be made into a particulate form, for example, and the particle diameter can be 10 micrometers or less.
The wavelength converter 21 is at least one of phosphors having a peak emission wavelength of 440 nm to 470 nm (blue), 500 nm to 555 nm (green), 560 nm to 580 nm (yellow), and 600 nm to 670 nm (red). The above may be included.
In addition, a phosphor having an emission wavelength band of 380 nm to 720 nm may be included.
As phosphors, silicon (Si), aluminum (Al), titanium (Ti), germanium (Ge), phosphorus (P), boron (B), yttrium (Y), alkaline earth element, sulfide element, rare earth It may include at least one element selected from the group consisting of elements and nitride elements.

Examples of the phosphor material that emits red fluorescence include the following. However, the phosphor emitting red fluorescence used in the embodiment is not limited to these.
Y ₂ O ₂ S: Eu,
Y ₂ O ₂ S: Eu + pigment,
Y ₂ O ₃ : Eu,
Zn ₃ (PO ₄ ) ₂ : Mn,
(Zn, Cd) S: Ag + In ₂ O ₃ ,
(Y, Gd, Eu) BO ₃ ,
(Y, Gd, Eu) ₂ O ₃ ,
YVO ₄ : Eu,
La ₂ O ₂ S: Eu, Sm,
LaSi ₃ N ₅ : Eu ²⁺ ,
α-sialon: Eu ²⁺ ,
CaAlSiN ₃ : Eu ²⁺ ,
CaSiN _X : Eu ²⁺ ,
CaSiN _X : Ce ²⁺ ,
M ₂ Si ₅ N ₈ : Eu ²⁺ ,
CaAlSiN ₃ : Eu ²⁺ ,
(SrCa) AlSiN ₃ : Eu ^{X +} ,
Sr _x (Si _y Al ₃ ) _z (O _x N): Eu ^{X +}

Examples of the phosphor material that emits green fluorescence include the following. However, the fluorescent substance which emits the green fluorescence used for embodiment is not limited to these.
ZnS: Cu, Al,
ZnS: Cu, Al + pigment,
(Zn, Cd) S: Cu, Al,
ZnS: Cu, Au, Al, + pigment,
Y ₃ Al ₅ O ₁₂ : Tb,
Y ₃ (Al, Ga) ₅ O ₁₂ : Tb,
Y ₂ SiO ₅ : Tb,
Zn ₂ SiO ₄ : Mn,
(Zn, Cd) S: Cu,
ZnS: Cu,
Zn ₂ SiO ₄ : Mn,
ZnS: Cu + Zn ₂ SiO ₄ : Mn,
Gd ₂ O ₂ S: Tb,
(Zn, Cd) S: Ag,
ZnS: Cu, Al,
Y ₂ O ₂ S: Tb,
ZnS: Cu, Al + In ₂ O ₃ ,
(Zn, Cd) S: Ag + In ₂ O ₃ ,
(Zn, Mn) ₂ SiO ₄ ,
BaAl ₁₂ O ₁₉ : Mn
(Ba, Sr, Mg) O.aAl ₂ O ₃ : Mn,
LaPO ₄ : Ce, Tb,
Zn ₂ SiO ₄ : Mn,
ZnS: Cu,
3 (Ba, Mg, Eu, Mn) O.8Al ₂ O ₃ ,
_{La 2 O 3 · 0.2SiO 2 ·} 0.9P 2 O 5: Ce, Tb,
CeMgAl ₁₁ O ₁₉ : Tb,
CaSc ₂ O ₄ : Ce,
(BrSr) SiO ₄ : Eu,
α-sialon: Yb ²⁺ ,
β-sialon: Eu ²⁺ ,
(SrBa) YSi ₄ N ₇ : Eu ²⁺ ,
(CaSr) Si ₂ O ₄ N ₇ : Eu ²⁺ ,
Sr (SiAl) (ON): Ce

Examples of the phosphor material that emits blue fluorescence include the following. However, the fluorescent substance which emits the blue fluorescence used for embodiment is not limited to these.
ZnS: Ag,
ZnS: Ag + pigment,
ZnS: Ag, Al,
ZnS: Ag, Cu, Ga, Cl,
ZnS: Ag + In ₂ O ₃ ,
ZnS: Zn + In ₂ O ₃ ,
(Ba, Eu) MgAl ₁₀ O ₁₇ ,
(Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) 6 Cl ₂ : Eu,
Sr ₁₀ (PO ₄ ) 6Cl ₂ : Eu,
(Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ ,
10 (Sr, Ca, Ba, Eu) · 6PO ₄ · Cl ₂ ,
BaMg ₂ Al ₁₆ O ₂₅ : Eu

Examples of the phosphor material that emits yellow fluorescence include the following. However, the fluorescent substance which emits yellow fluorescence used for embodiment is not limited to these.
Li (Eu, Sm) W ₂ O ₈ ,
(Y, Gd) ₃ , (Al, Ga) ₅ O ₁₂ : Ce ³⁺ ,
Li ₂ SrSiO ₄ : Eu ²⁺ ,
(Sr (Ca, Ba)) ₃ SiO ₅ : Eu ²⁺ ,
SrSi ₂ ON _2.7 : Eu ²⁺

Examples of the phosphor material that emits yellow-green fluorescence include the following. However, the phosphor emitting yellow-green fluorescence used in the embodiment is not limited to this.
SrSi ₂ ON _2.7 : Eu ²⁺
Examples of the resin in which the phosphor is dispersed include epoxy resin, silicone resin, methacrylic resin (PMMA), polycarbonate (PC), cyclic polyolefin (COP), alicyclic acrylic (OZ), and allyl diglycol carbonate (ADC). ), Acrylic resin, fluorine resin, hybrid resin of silicone resin and epoxy resin, urethane resin, and the like.
The refractive index of the resin in which the phosphor is dispersed is preferably less than or equal to the refractive index of the phosphor. The transmittance of the resin in which the phosphor is dispersed is preferably 90% or more.

In this case, when the light emitted from the semiconductor light emitting element 3 is ultraviolet to blue light having a short wavelength and the luminance is high, the resin forming the wavelength conversion unit 21 may be deteriorated. For this reason, it is preferable that the resin forming the wavelength conversion unit 21 is not easily deteriorated by blue light or the like. Examples of the resin that is hardly deteriorated by blue light and the like include methylphenyl silicone, dimethyl silicone, a hybrid resin of methylphenyl silicone and epoxy resin having a refractive index of about 1.5.
However, the resin in which the phosphor is dispersed is not limited to those illustrated, and can be appropriately changed.

As mentioned above, although several embodiment of this invention was illustrated, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, changes, and the like can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and the equivalents thereof.
For example, the shape, size, material, arrangement, number, and the like of each element included in the semiconductor light emitting device 1 and the semiconductor light emitting device 1a are not limited to those illustrated, but can be changed as appropriate. Further, the above-described embodiments can be implemented in combination with each other.

  DESCRIPTION OF SYMBOLS 1 Semiconductor light-emitting device, 1a Semiconductor light-emitting device, 2 base part, 3 Semiconductor light-emitting device, 4 junction part, 4a junction part, 5 board | substrate, 6 Conductive film, 7 Light emitting layer, 8 base | substrate, 9 electrode, 10 electrode, 11 base, 12 Wiring part, 17 resin, 18 conductor, 18a conductor, 19 reflector, 19a reflector, 20 reflector, 21 wavelength converter

Claims (8)

The base,
A semiconductor light-emitting element comprising: a first electrode provided on a first surface; and a second electrode provided on a second surface opposite to the first surface;
A joint provided between the base and the second electrode;
With
The bonding portion includes a resin portion, and a conductive conductor and a reflector that reflects light emitted from the semiconductor light emitting element are dispersed in the resin portion. A semiconductor light emitting device. The volume ratio of the conductor in the resin portion is 40% or more and 90% or less,
The semiconductor light emitting device according to claim 1, wherein a volume ratio of the reflector in the resin portion is 5% or more and 40% or less.   3. The semiconductor light emitting device according to claim 1, wherein a light reflectance of the reflector with respect to light emitted from the semiconductor light emitting element is 85% or more. The semiconductor light-emitting device according to claim 1, wherein the conductor and the reflector have a spherical shape and satisfy the following expression.

Here, R is an average radius of the conductor, and r is an average radius of the reflector.   4. The reflector according to claim 1, wherein the reflector is formed of a white pigment and has at least one shape selected from the group consisting of a scale shape, a flat shape, and a spherical shape. The semiconductor light-emitting device described in 1.   The semiconductor light-emitting device according to claim 1, wherein the conductor has a scale shape, and the reflector has a spherical shape.   The semiconductor light-emitting device according to claim 1, wherein the conductor has a spherical shape, and the reflector has an aspherical shape.   The semiconductor light emitting device according to claim 1, wherein the conductor has a scale shape, and the reflector has an aspheric shape.

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