JP4771800B2 - Semiconductor light emitting device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor light emitting device and its manufacturing method wherein uneven colors of mixed light of emitted light from a light emitting element chip and excitation light by a wavelength conversion material is prevented from occurring, and it has a high light derivation efficiency with a simplified structure. <P>SOLUTION: The semiconductor light emitting device 10 includes a substrate 11 having a recess 11a in an upper surface thereof, a semiconductor light emitting element 12 disposed on the bottom surface of the recess, and wavelength conversion layers 13, 15 for converting the wavelengths of light beams from the semiconductor light emitting element. The semiconductor light emitting device 10 further includes a first wavelength conversion layer 13 disposed excepting a just above region of the semiconductor light emitting element at a height separated off upward from a bottom surface of the recessed part, and a second wavelength conversion layer 15 disposed at a height separated above from the upper surface of the semiconductor light emitting element. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a semiconductor light-emitting device using a semiconductor light-emitting element, and in particular, emits light from the semiconductor light-emitting element through a wavelength conversion layer, and emits light from the light-emitting element chip and excitation light from the wavelength conversion layer. The present invention relates to a semiconductor light emitting device mixed and emitted to the outside, and a manufacturing method thereof.

Conventionally, such a semiconductor light-emitting device is configured, for example, as shown in Patent Document 1.
That is, according to Patent Document 1, as shown in FIG. 8, a semiconductor light emitting device 1 includes a base 2, a semiconductor light emitting element 3 disposed in a recess 2a provided on the upper surface of the base 2, and the recess 2a. The first wavelength conversion layer 4 formed on the bottom surface of the first, the sealing portion 5 filled in the recess 2a, and the second formed near the surface of the sealing portion 5 at the upper edge of the recess 2a. And a wavelength conversion layer 6.

Here, the base body 2 includes a substrate portion 2b having a pair of extraction electrodes 7a and 7b on the upper surface, and a reflection frame portion 2c having the above-described concave portion 2a placed on the substrate portion 2b. It is composed of
The substrate portion 2b is made of an insulating material, and the reflection frame portion 2c is made of an insulating material having heat resistance.
The lead electrodes 7a and 7b have one end exposed at the bottom surface in the recess 2a and the other end of the lead portion 7b from the side edge to the bottom surface of the substrate portion 2b. The terminal portion is formed.

In the illustrated case, the reflection frame portion 2c includes a recess 2a having a substantially vertical or upwardly extending side wall formed so as to surround the semiconductor light emitting element 3 disposed in the center from both sides. The concave portion 2a is formed of a white material so that the inner surface has reflection characteristics, or provided with a reflection surface by coating, plating, vapor deposition, or the like on the inner surface.
The reflection frame portion 2c may be formed in an inverted truncated cone shape so as to surround the semiconductor light emitting element 3 from the entire circumference.

  The reflection frame portion 2c may be integrally formed with the substrate portion 2b so that the extraction electrodes 7a and 7b are insert-molded, and the substrate portion on which the semiconductor light emitting element 3 is mounted. You may affix on the upper surface of 2b.

The semiconductor light emitting element 3 is configured to emit light having a wavelength that can excite a wavelength conversion material to be described later.
The semiconductor light emitting device 3 is mechanically and electrically connected to the lead electrode 7a by die bonding on the tip of one lead electrode 7a exposed at the bottom surface of the recess 2a of the base 2. Connected to.
The semiconductor light emitting device 3 is electrically connected to the lead electrode 7b by wire bonding an electrode portion (not shown) on the upper surface to the tip of the other lead electrode 7b. It has become.

  The semiconductor light emitting element 3 may be configured to include two electrode portions on the upper surface. In this case, each electrode portion is electrically connected to both the extraction electrodes 7a and 7b by wire bonding. Will be connected.

The first wavelength conversion layer 4 includes a wavelength conversion material such as inorganic phosphor particles, for example, and is excited by light from the semiconductor light emitting element 3 to emit wavelength-converted light (first wavelength light). It is like that.
The first wavelength conversion layer 4 is disposed in the bottom region of the recess 2 a of the base 2, and is located on the surface of the substrate portion 2 b and the upper surface of the semiconductor light emitting element 3 in the illustrated case. .

The sealing portion 5 transmits light from the semiconductor light emitting element 3 and first wavelength light from the first wavelength conversion layer 4 and preferably second wavelength light (described later) from the second wavelength conversion layer 6. For example, it is made of a thermosetting resin or low-melting glass.
Here, the sealing portion 5 is preferably formed such that its upper surface is curved in a concave shape.

The second wavelength conversion layer 6 contains a wavelength conversion material such as inorganic phosphor particles, for example, and is excited by light from the semiconductor light emitting element 3 to emit wavelength-converted light (second wavelength light). It is like that.
The second wavelength conversion layer 4 is separated from the semiconductor light emitting element 3 upward, that is, in a relatively wide central region of the upper edge of the recess 2a of the substrate 2, specifically in the recess 2a. It is arrange | positioned on the upper surface of the sealing part 5 with which it filled.

Here, the first wavelength conversion layer 4 is composed of, for example, a wavelength conversion material such as inorganic phosphor particles mixed in a thermosetting resin and applied to the bottom surface of the recess 2a, or the sealing portion 5 is configured. It is formed by mixing a wavelength conversion material in the translucent resin material to be filled, filling the recess 2a, and allowing the wavelength conversion material to settle.
And after the sealing part 5 is filled so that the semiconductor light-emitting device 3 may be covered in the said recessed part 2a, the 2nd wavelength conversion which contains the fluorescent substance as a predetermined amount of particulate wavelength conversion agents on it Layer 6 is applied.

According to the semiconductor light emitting device 1 having such a configuration, when a driving voltage is applied to the semiconductor light emitting element 3 through the pair of extraction electrodes 7a and 7b, the semiconductor light emitting element 3 emits light.
Of the light L from the semiconductor light emitting element 3, the light emitted in the optical axis direction substantially vertically upward is transmitted through the first wavelength conversion layer 4, and a part thereof is the second wavelength conversion layer. 6, the other part is wavelength-converted by the second wavelength conversion layer 6 to be reflected as the second wavelength light L 2, and the remaining light is further reflected by the second wavelength conversion layer 6. After being reflected, it enters the first wavelength conversion layer 4 again.
A part of the incident light is reflected by the first wavelength conversion layer 4 and radiates upward, and the other part is wavelength-converted by the first wavelength conversion layer 4 to be the first wavelength. The light L1 is emitted upward.

On the other hand, a part of the light that is off the optical axis and is emitted obliquely downward from the side surface enters the first wavelength conversion layer 4 to be wavelength-converted to become the first wavelength light L1. Is reflected by the first wavelength conversion layer 4 and emitted upward.
Therefore, the first wavelength light L1 and the second wavelength light L2 described above are mixed with the light L from the semiconductor light emitting element 3, so that light emission characteristics of uniform color as a whole can be obtained.

In this way, a semiconductor light emitting device with less color unevenness and less brightness unevenness can be configured with a simple configuration at low cost.
In addition, when the wavelength conversion material contained in the 1st wavelength conversion layer 4 and the 2nd wavelength conversion layer 6 is the same, the 1st wavelength light L1 and the 2nd wavelength light L2 become the light of the same color. As a result, light emission characteristics with more uniform color unevenness can be obtained as a whole.
JP 2005-191420 A

However, the semiconductor light emitting device 1 having such a configuration has the following problems.
That is, since the first wavelength conversion layer 4 is also disposed immediately above the semiconductor light emitting element 3, the light L emitted from the semiconductor light emitting element 3 is emitted most vertically upward in the optical axis direction. The light having high excitation intensity is first transmitted through the first wavelength conversion layer 4, reflected by the second wavelength conversion layer 6, and then reflected by the first wavelength conversion layer 4. The transmission / reflection by is repeated three times.

For this reason, the light with the strongest excitation intensity is greatly attenuated by the transmission / reflection, so that the light extraction efficiency is relatively low. For example, in the case of a white LED filled with a phosphor by general potting The light extraction efficiency will be about the same as that.
Therefore, along with a demand for higher output of the semiconductor light emitting device, a semiconductor light emitting device having higher light extraction efficiency has been demanded.

  Such inconveniences also exist in various semiconductor light emitting devices such as LEDs that emit mixed color light of light from various semiconductor light emitting elements and excitation light of a wavelength conversion agent. In addition to an LED of a type in which a lead frame is insert-molded, it is formed of a conductive thin film that, for example, has a recess formed on the upper surface of a semiconductor substrate, and extends from the bottom of the recess through the side surface to the upper surface and possibly the lower surface of the substrate. The same applies to semiconductor light-emitting devices such as LEDs of the type provided with an electrode layer.

  In view of the above, the present invention has a simple configuration and does not cause color unevenness in the mixed color light of the light emitted from the light emitting element chip and the excitation light by the wavelength conversion agent, and has high light extraction efficiency. An object of the present invention is to provide a semiconductor light emitting device and a manufacturing method thereof.

  According to the first configuration of the present invention, the object is to provide a base having a recess on the upper surface, a semiconductor light emitting device disposed on the bottom surface of the recess, and wavelength conversion for wavelength conversion of light from the semiconductor light emitting device. A first wavelength conversion layer disposed excluding a region directly above the semiconductor light emitting element at a height position away from the bottom surface of the recess, and the semiconductor light emitting device. This is achieved by a semiconductor light emitting device comprising a second wavelength conversion layer disposed at a height position away from the upper surface of the element.

  The semiconductor light emitting device according to the present invention preferably includes a sealing portion that is filled in the recess and is made of a translucent material that does not absorb light from the semiconductor light emitting element.

  In the semiconductor light emitting device according to the present invention, preferably, the first wavelength conversion layer is disposed near the lower surface of the two-stage sealing portion.

  In the semiconductor light emitting device according to the present invention, preferably, the second wavelength conversion layer is disposed near the upper surface of the two-stage sealing portion.

  In the semiconductor light emitting device according to the present invention, preferably, a transparent substrate that penetrates through the first wavelength conversion layer is placed directly on the semiconductor light emitting element.

  In the semiconductor light emitting device according to the present invention, preferably, the first wavelength conversion layer is formed on the lower surface of the transparent substrate.

  In the semiconductor light emitting device according to the present invention, preferably, the second wavelength conversion layer is formed on the upper surface of the transparent substrate.

  In the semiconductor light emitting device according to the present invention, preferably, the first wavelength conversion layer has a substantially parabolic cross section that curves upward from the inner edge facing the semiconductor light emitting element toward the outside in the radial direction.

  In the semiconductor light emitting device according to the present invention, preferably, the upper surface of the sealing portion includes a recess in the vicinity of the center immediately above the semiconductor light emitting element.

In the semiconductor light emitting device according to the present invention, preferably, the first wavelength conversion layer and the second wavelength conversion layer are A ₃ B ₅ O ₁₂ : M (A: Y, Gd, Lu, Tb, B: Al, Ga, M: Ce ³⁺ , Tb ³⁺ , Eu ³⁺ , Cr ³⁺ , Nd ³⁺ or Er ³⁺ ), BAM phosphor (barium-aluminum-magnesium compound phosphor doped with rare earth), Y ₂ O ₂ S: Eu ³⁺ , ZnS: Sulfide compound phosphors such as Cu, Al or (Sr, Ca) S: Eu ²⁺ , CaGa ₂ S ₄ : Eu ²⁺ or SrGa ₂ S ₄ : Eu ²⁺ At least one composition of a rare earth-doped thiogallate phosphor such as TbAlO ₃ : Ce ³⁺ or an orthosilicate such as (Ba, Ca, Eu) _x Si _y O _z : Eu ²⁺ It contains the contained phosphor.

  In the semiconductor light emitting device according to the present invention, preferably, the sealing portion contains at least one resin of an epoxy resin, a silicone resin, a polydimethylsiloxane derivative having an epoxy group, an oxetane resin, an acrylic resin, or a cycloolefin resin. It is made of resin.

  According to the second configuration of the present invention, the semiconductor light emitting element is disposed in the recess provided on the upper surface of the base, and the region directly above the semiconductor light emitting element is located at a height away from the bottom of the recess. The first wavelength conversion layer is arranged except for the above, and the second wavelength conversion layer is arranged at a height position away from the upper surface of the semiconductor light emitting element so that the emitted light from the light emitting element chip is A method for manufacturing a semiconductor light emitting device, wherein wavelength conversion is performed by one wavelength conversion layer and a second wavelength conversion layer, and mixed color light of wavelength-converted light and light from a semiconductor light emitting element is emitted to the outside. Mix the wavelength conversion material of the first wavelength conversion layer into the material that forms the sealing portion to be filled in the recess, fill it up to a height in the middle of the recess, and turn the base upside down. The first wavelength conversion layer and the sealing portion are cured by curing in the state Characterized in that it includes the step of forming a lower, by the method of manufacturing a semiconductor light emitting device is achieved.

  In the method for manufacturing a semiconductor light emitting device according to the present invention, preferably, the second wavelength is contained in a material for forming a sealing portion to be filled in the concave portion in which the first wavelength conversion layer is formed. By mixing the wavelength conversion material of the conversion layer, filling up to the height position of the upper edge of the recess, and curing the base body upside down, the upper stage of the second wavelength conversion layer and the sealing portion Including the step of forming.

  In the method for manufacturing a semiconductor light emitting device according to the present invention, preferably, before the step of forming the first wavelength conversion layer and the lower stage of the sealing portion, the first wavelength conversion layer is provided directly on the semiconductor light emitting element. A step of disposing a transparent substrate extending upward to a position exceeding the height;

  In the method of manufacturing a semiconductor light emitting device according to the present invention, preferably, the second substrate is disposed in the concave portion in which the first wavelength conversion layer is formed by disposing the transparent substrate having the second wavelength conversion layer on the upper surface. Forming a wavelength conversion layer.

  According to the third configuration of the present invention, the semiconductor light emitting element is disposed in the recess provided on the upper surface of the base, and the region directly above the semiconductor light emitting element is located at a height away from the bottom of the recess. The first wavelength conversion layer is arranged except for the above, and the second wavelength conversion layer is arranged at a height position away from the upper surface of the semiconductor light emitting element so that the emitted light from the light emitting element chip is A method for manufacturing a semiconductor light emitting device, wherein wavelength conversion is performed by one wavelength conversion layer and a second wavelength conversion layer, and mixed color light of wavelength-converted light and light from a semiconductor light emitting element is emitted to the outside. By disposing a transparent substrate in which the first wavelength conversion layer is provided on the lower surface and the second wavelength conversion layer is provided on the upper surface in the recess, the first wavelength conversion layer and the second wavelength conversion layer are provided. Semiconductor light emission characterized in that it comprises a step of forming The method of manufacturing location, is achieved.

According to the first configuration, when a drive voltage is applied to the semiconductor light emitting element, the semiconductor light emitting element 3 emits light. Of the light from the semiconductor light emitting element 3, a part of the light emitted in the optical axis direction substantially perpendicularly upward is partially transmitted through the second wavelength conversion layer and the other part is second. The wavelength converted by the wavelength conversion layer is converted into the second wavelength light and reflected downward, and the remaining light is reflected by the second wavelength conversion layer, and then proceeds downward to enter the first wavelength conversion layer. Is incident on.
A part of this incident light is reflected by the first wavelength conversion layer and radiates upward, and another part of the incident light is wavelength-converted by the first wavelength conversion layer and is converted into the first wavelength light. It will be emitted upward.

In addition, a part of the light that is off the optical axis and is emitted obliquely downward from the side surface is incident on the first wavelength conversion layer to be converted into the first wavelength light, and the other part is the first wavelength light. The light passes through one wavelength conversion layer and is emitted upward.
Therefore, the above-described first wavelength light and second wavelength light are mixed with light from the semiconductor light emitting element, so that light emission characteristics with uniform color as a whole can be obtained.

In this case, since the first wavelength conversion layer is not provided in the region immediately above the semiconductor light emitting element, the light emitted from the semiconductor light emitting element in the optical axis direction does not need to pass through the first wavelength conversion layer. Therefore, the transmission loss at the time of transmission through the first wavelength conversion layer is eliminated, and the light extraction efficiency is improved.
In addition, since the first wavelength conversion layer is disposed above the bottom surface of the substrate recess, all the light emitted from the side surface of the semiconductor light emitting element is incident on the first wavelength conversion layer. The wavelength conversion efficiency in one wavelength conversion layer is improved.

  In a case where the sealing portion is made of a translucent material that is filled in the recess and does not absorb light from the semiconductor light emitting element, the sealing portion causes the semiconductor light emitting element in the base recess to be It will be held fixed and protected.

  When the first wavelength conversion layer is disposed near the lower surface of the two-stage sealing portion, the first wavelength conversion layer is stably held on the lower surface of the sealing portion. At the same time, the wavelength conversion is performed by mixing the material constituting the sealing portion with the wavelength conversion agent for the first wavelength conversion layer, filling the concave portion, and curing the material by turning it upside down. Since the agent settles near the lower surface of the sealing portion due to gravity, the first wavelength conversion layer can be easily formed.

  When the second wavelength conversion layer is disposed near the upper surface of the two-stage sealing portion, the second wavelength conversion layer is stably formed on the upper surface of the sealing portion in the same manner. At the time of manufacture, by mixing the wavelength conversion agent for the second wavelength conversion layer into the material constituting the sealing portion, filling the concave portion, and then rotating it upside down to cure Since the wavelength conversion agent settles near the upper surface of the sealing portion due to gravity, the second wavelength conversion layer can be easily formed.

  When a transparent substrate that penetrates the first wavelength conversion layer is placed immediately above the semiconductor light emitting element, the first wavelength conversion layer is formed directly above the semiconductor light emitting element when the first wavelength conversion layer is formed. It can be reliably prevented that the wavelength conversion layer is formed.

  When the first wavelength conversion layer is formed on the lower surface of the transparent substrate, or when the second wavelength conversion layer is formed on the upper surface of the transparent substrate, the lower surface or the upper surface of the transparent substrate is used. By forming the first wavelength conversion layer and the second wavelength conversion layer, respectively, by disposing the transparent substrate in the substrate recess, the first wavelength conversion layer and / or the predetermined wavelength in the recess The second wavelength conversion layer is disposed, and can be easily assembled with a simple configuration.

  In the case where the first wavelength conversion layer has a substantially parabolic cross section that curves upward from the inner edge facing the semiconductor light emitting element toward the radially outer side, the lower stage of the sealing portion in a state where the top and bottom are reversed. As the thickness of the first wavelength conversion layer gradually increases toward the outside in the radial direction when hardening in the recess, the first wavelength conversion is performed in the peripheral region where the amount of incident light is relatively small. Since the amount of wavelength-converted light by the layer is increased, the amount of wavelength-converted light is made uniform.

  When the upper surface of the sealing portion has a recess near the center immediately above the semiconductor light emitting element, the recess of the sealing portion formed in advance is filled with the material of the second wavelength conversion layer by potting or the like. Thus, the second wavelength conversion layer can be easily formed.

The first wavelength conversion layer and the second wavelength conversion layer include A ₃ B ₅ O ₁₂ : M (A: Y, Gd, Lu, Tb, B: Al, Ga, M: Ce ³⁺ , Tb ^3+. , Eu ³⁺ , Cr ³⁺ , Nd ³⁺ or Er ³⁺ ), BAM phosphor (barium-aluminum-magnesium compound phosphor doped with rare earth), Y ₂ O ₂ S: Eu ³⁺ or ZnS: Cu Sulfide-based compound phosphors such as Al, Al or thiogallate phosphors doped with rare earth such as (Sr, Ca) S: Eu ²⁺ , CaGa ₂ S ₄ : Eu ²⁺ or SrGa ₂ S ₄ : Eu ²⁺ When a phosphor containing at least one composition of aluminate such as TbAlO ₃ : Ce ³⁺ or orthosilicate such as (Ba, Ca, Eu) _x Si _y O _z : Eu ²⁺ is included By using these general wavelength conversion agents, the wavelength conversion layer can be easily Can be formed.

  When the sealing part is composed of an epoxy resin, a silicone resin, a polydimethylsiloxane derivative having an epoxy group, an oxetane resin, an acrylic resin, or a resin containing at least one of a cycloolefin resin. By using these general resin materials, it is possible to easily form a sealing portion having translucency with respect to light from the semiconductor light emitting element and wavelength converted light from each wavelength conversion layer. become.

According to said 2nd structure, the wavelength conversion agent for the 1st wavelength conversion layer is mixed with the material which comprises a sealing part, it fills in a recessed part, and it is made to invert and harden | cure the wavelength, Since the conversion agent settles near the lower surface of the sealing portion due to gravity, the semiconductor light emission occurs in the recess of the base material, near the lower surface of the sealing portion, that is, at a height away from the bottom surface of the recess. The first wavelength conversion layer is formed except for the region directly above the element. Therefore, since the first wavelength conversion layer is not provided in the region directly above the semiconductor light emitting element, light emitted from the semiconductor light emitting element in the optical axis direction does not need to pass through the first wavelength conversion layer. The transmission loss during transmission through the first wavelength conversion layer is eliminated, and the light extraction efficiency is improved.
In addition, since the first wavelength conversion layer is disposed above the bottom surface of the substrate recess, all the light emitted from the side surface of the semiconductor light emitting element is incident on the first wavelength conversion layer. The wavelength conversion efficiency in one wavelength conversion layer is improved.

In the concave portion in which the first wavelength conversion layer is formed, the wavelength converting material of the second wavelength conversion layer is further mixed with the material forming the sealing portion to be filled in the concave portion, If it includes the step of forming the second wavelength conversion layer and the upper part of the sealing part by filling up to the height of the edge and curing the substrate in an upside down state, the same applies. The wavelength converting agent for the second wavelength conversion layer is mixed with the material constituting the sealing portion, filled in the recesses, and reversed and cured, so that the wavelength converting agent is sealed by gravity. The second wavelength conversion layer is formed in the vicinity of the upper surface, i.e., at a height away from the surface of the semiconductor light emitting device.
As a result, the light emitted upward from the upper surface of the semiconductor light emitting element along the optical axis direction enters the second wavelength conversion layer without passing through the first wavelength conversion layer. The wavelength conversion efficiency in the wavelength conversion layer is improved.

  Prior to the step of forming the first wavelength conversion layer and the lower part of the sealing portion, a transparent base material extending upward to a height position exceeding the first wavelength conversion layer is disposed immediately above the semiconductor light emitting element. When the first wavelength conversion layer and the lower part of the sealing part are formed, when the material of the sealing part is filled in the recess, the region directly above the semiconductor light emitting element The material of the sealing part is not filled. Therefore, it can be reliably prevented that the first wavelength conversion layer is formed in the region immediately above the semiconductor light emitting element.

  A step of forming a second wavelength conversion layer by disposing a transparent substrate having a second wavelength conversion layer provided on the upper surface in the recess in which the first wavelength conversion layer is formed; By disposing the transparent substrate in the recess, it is not necessary to wait for the upper stage of the sealing portion to be cured, and the second wavelength conversion layer can be formed in a short time.

  According to the third configuration, by forming the first wavelength conversion layer and the second wavelength conversion layer on the lower surface or the upper surface of the transparent substrate, respectively, by disposing the transparent substrate in the base recess. The first wavelength conversion layer and / or the second wavelength conversion layer is disposed at a predetermined position in the recess, and can be easily assembled with a simple configuration and forms a sealing portion. Since no curing time is required for the material to be assembled, assembly can be performed in a short time.

Thus, according to the present invention, since the first wavelength conversion layer is not provided in the region immediately above the semiconductor light emitting element, the light emitted from the semiconductor light emitting element in the optical axis direction is converted into the first wavelength conversion. Since there is no need to transmit the layer, the transmission loss at the time of transmission through the first wavelength conversion layer is eliminated, and the light extraction efficiency is improved. In addition, since the first wavelength conversion layer is disposed above the bottom surface of the substrate recess, all the light emitted from the side surface of the semiconductor light emitting element is incident on the first wavelength conversion layer. The wavelength conversion efficiency in one wavelength conversion layer is improved.
Furthermore, according to the present invention, since a lead frame as a conventional extraction electrode can be used as it is, no new equipment cost is required, and a transmissive and reflective semiconductor light emitting device can be manufactured at low cost. It is.

In addition, when the semiconductor light emitting element as the excitation light source emits near ultraviolet light, luminance unevenness is reduced and transmitted excitation light emitted to the outside can be suppressed, so that deterioration of the light guide plate or the like due to ultraviolet light is prevented. It can be prevented.
Furthermore, in the case of a semiconductor light-emitting device that emits white light to the outside by mixing the excitation light and wavelength-converted light, color unevenness and luminance unevenness can be reduced. The device can be manufactured.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

[Example 1]
FIG. 1 shows a first embodiment of a semiconductor light emitting device according to the present invention.
In FIG. 1, a semiconductor light emitting device 10 includes a base 11, a semiconductor light emitting element 12 disposed in a recess 11a provided on the upper surface of the base 11, and a first formed away from the bottom of the recess 11a. The wavelength conversion layer 13, the sealing portion 14 filled in the recess 11 a, and the second wavelength conversion layer 15 formed near the surface of the sealing portion 14 at the upper edge of the recess 11 a Has been.

Here, the base body 11 includes a substrate portion 11b having a pair of extraction electrodes 16a and 16b on the upper surface, and a reflection frame portion 11c having the above-described recess 11a placed on the substrate portion 11b. It is composed of
The substrate portion 11b is made of an insulating material such as glass or epoxy resin, and the reflecting frame portion 11c is made of an insulating material having heat resistance.
One end of each of the extraction electrodes 16a and 16b is exposed on the bottom surface in the recess 11a, and the other end of each of the extraction electrodes 16a and 16b extends from the side edge to the bottom surface of the substrate portion 11b. The terminal portion is formed.
The base 11 and the lead electrodes 16a and 16b may be in any form as long as the semiconductor light emitting element 12 is fixed on the base 11 and electrically connected to the lead electrodes 16a and 16b. .

In the illustrated case, the reflection frame portion 11c includes a recess 11a having a side wall that extends substantially vertically or upward so as to surround the semiconductor light emitting element 12 disposed in the center from both sides (or the entire circumference). In addition, the inner surface of the recess 11a may be formed of a white material so that the inner surface of the recess 11a has reflection characteristics, or may be provided with a reflecting surface having a high reflectance by coating, plating, vapor deposition, or the like.
Here, the concave portion 11a is formed so as to be inclined so that the inner surface of the concave portion 11a expands upward, for example, in the shape of an inverted truncated cone or an inverted quadrangular pyramid. The inner surface may be formed substantially vertically.
The reflection frame portion 11c may be formed integrally with the substrate portion 11b, or may be bonded to the substrate portion 11b by adhesion or the like.

  The reflection frame portion 11c may be integrally formed with the substrate portion 11b so that the extraction electrodes 16a and 16b are insert-molded, and the substrate portion on which the semiconductor light emitting element 12 is mounted. You may affix on the upper surface of 11b.

The semiconductor light emitting element 12 is configured to emit light having a wavelength capable of exciting a wavelength conversion material to be described later, for example, ultraviolet light to blue light (emission peak wavelength range of about 300 to 490 nm).
Specifically, the semiconductor light emitting device 12 typically includes a group III-nitrogen compound (InGaAlN) semiconductor, a zinc oxide compound (ZnMgO) semiconductor, and a zinc selenide compound (ZnMgSeSTe) semiconductor. , Silicon carbide compound (SiGeC) semiconductors and the like are used.

The semiconductor light emitting element 12 is fixed with an adhesive such as an epoxy resin on the leading end of the one extraction electrode 16a exposed on the bottom surface of the recess 11a of the base 11 or on the bottom surface of the recess 11a.
The semiconductor light emitting device 12 has two electrode portions (not shown) on the upper surface thereof wire-bonded to the leading ends of the extraction electrodes 16a and 16b, respectively, so that each of the extraction electrodes 16a and 16b is electrically connected. Connected.

The semiconductor light emitting element 12 may be configured to have an electrode portion on each of the lower surface and the upper surface. In this case, the semiconductor light emitting element 12 is die-bonded on the one extraction electrode 16a and the electrode on the upper surface. The portion is electrically connected to the other extraction electrode 16b by wire bonding.
In addition, the semiconductor light emitting element 12 may be configured to have electrode portions on both side edges of the lower surface. In this case, the semiconductor light emitting element 12 has electrode electrodes on both side edges of the lower surface corresponding to the extraction electrodes. The eutectic material such as Au-Sn, Au bump, conductive sheet having anisotropy, conductive resin such as Ag paste, etc. so as to straddle between the extraction electrodes 16a and 16b so as to come into contact with 16a and 16b It is fixed to the bottom surface of the recess 11a and is electrically connected to both the extraction electrodes 16a and 16b.
Furthermore, the base body 11 may be made of a conductive material such as a metal, and the base body 11 may also function as one extraction electrode 16a.

The first wavelength conversion layer 13 includes a wavelength conversion material such as inorganic phosphor particles, for example, and is excited by light from the semiconductor light emitting element 12 to emit wavelength-converted light (first wavelength light). It is like that.
The first wavelength conversion layer 13 is disposed in a height position away from the bottom surface in the concave portion 11a of the base body 11, and the top surface of the first wavelength conversion layer 13 is directed radially outward from the inner edge. It has a substantially parabolic cross section so that it is curved. The upper surface of the first wavelength conversion layer 13 may be formed in an arbitrary shape, for example, flat.
Further, the first wavelength conversion layer 13 is located at a height position near the upper surface of the semiconductor light emitting element 12, and in the illustrated case, the inner edge facing the semiconductor light emitting element 12 is near the upper surface of the semiconductor light emitting element 12. It is located at the height position.

The sealing portion 14 is made of a translucent material that is transparent from the emission peak wavelength of light from the semiconductor light emitting element 12 to a short wavelength region.
As long as the material of the sealing part 14 can further mix the wavelength conversion material of the first wavelength conversion layer 13 and the wavelength conversion material of the first wavelength conversion layer 13 can be settled by heating, leaving, etc. A thermosetting resin, low melting point glass, or the like can be used.
In addition, since the specific gravity of a general resin is about 1.1, and the specific gravity of a general BAM phosphor as a wavelength conversion material to be used is about 3.8, the wavelength conversion material can settle.

  Specifically, in the embodiment of the present invention, a thermosetting resin is used as the material of the sealing portion 14 and an epoxy resin, a silicone resin, a polydimethylsiloxane derivative having an epoxy group, an oxetane resin, an acrylic resin, or a cyclo resin. Resins containing at least one olefin resin can be used.

In the case shown in the drawing, the sealing portion 14 is configured in a two-stage configuration, and the first wavelength conversion layer 13 is disposed on the upper surface of the lower stage 14a, and the second wavelength conversion layer is disposed on the upper surface of the upper stage 14b. 15 is arranged.
Furthermore, the upper stage 14b of the sealing part 14 is provided with a recessed part 14c by forming its upper surface curved in a concave shape.
Here, the upper stage 14b of the sealing portion may be made of a material different from that of the lower stage 14a. In this case, the material of the upper stage 14b may be any material that has excellent adhesion to the lower stage 14a and is not deteriorated by the excitation light from the semiconductor light emitting element 12.

The second wavelength conversion layer 15 includes a wavelength conversion material such as inorganic phosphor particles, for example, and is excited by light from the semiconductor light emitting element 12 to emit wavelength-converted light (second wavelength light). It is like that.
The second wavelength conversion layer 13 is separated upward from the semiconductor light emitting element 12, that is, in a relatively wide central region of the upper edge of the recess 11a of the base 11, specifically, in the recess 11a. It is arranged on the upper surface of the sealing part 14 filled with.

  Here, the positional relationship between the first wavelength conversion layer 13 and the second wavelength conversion layer 15 is such that, for example, the semiconductor light emitting element 12 emits ultraviolet light, and the first wavelength conversion layer 13 and the second wavelength conversion layer. In the case where white phosphor or other color light is extracted by exciting the 15 phosphors with the ultraviolet light, the ultraviolet light from the semiconductor light emitting element 12 is arranged not to be directly emitted to the outside, and each wavelength conversion is performed. The thickness and material of the layers 13 and 15 are selected.

According to the manufacturing method of this invention, the said 1st wavelength conversion layer 13, the 2nd wavelength conversion layer 15, and the sealing part 14 are formed as follows.
That is, the first wavelength conversion layer 13 is obtained by mixing a wavelength conversion material such as inorganic phosphor particles in the resin material for forming the sealing portion 14, so that the height position in the middle of the recess 11 a is obtained. And the substrate 11 is cured in a state of being inverted, so that the wavelength conversion material settles in the resin material based on gravity, and the upper surface of the sealing portion 14 having a substantially parabolic cross section is provided below. 14a is formed on the surface at the same time. At that time, based on the surface tension of the resin material filled in the recess 11a, the resin material crawls up along the inner surface of the recess 11a, and the substantially parabolic shape of the upper surface of the first wavelength conversion layer 13 described above. The cross section can be easily formed.
In this case, the first wavelength conversion layer 13 gradually increases in thickness toward the outer side in the radial direction based on the above-described substantially parabolic cross-sectional shape of the upper surface of the lower stage 14a of the sealing portion 14, The amount or concentration of the wavelength converting material increases toward the surface.

This parabolic cross-sectional shape is set in accordance with the light distribution characteristics of the semiconductor light emitting element 12.
That is, when the semiconductor light emitting element 12 irradiates light exclusively toward the bottom surface of the recess 11a, for example, like an MB chip manufactured by Cree, the apex of the parabolic cross section of the first wavelength conversion layer 13 is It is desirable to be at the upper end of the semiconductor light emitting element 12 or at a higher position.

When the apex of the parabolic cross-sectional shape of the first wavelength conversion layer 13 is lower than the upper end of the semiconductor light emitting element 12, the first wavelength conversion layer 13 and the second wavelength conversion layer are used. 15, a spacer portion formed of a resin material of the sealing portion 14 may be disposed.
Here, the spacer portion facilitates the formation of the second wavelength conversion layer 15, the excitation light from the semiconductor light emitting element 12 on the bottom surface of the second wavelength conversion layer 15, and the first wavelength conversion layer 13. In order to efficiently diffuse the wavelength-converted light, it can be formed in a concave shape in the region immediately above the semiconductor light emitting element 12.
This concave shape can be formed by utilizing shrinkage due to solvent volatilization during curing, or by causing a meniscus phenomenon by controlling the resin material, or by compression molding or the like.

Here, the filling of the resin material into the concave portion 11a is normally performed up to the same height as the upper edge of the concave portion 11a, or until it is slightly recessed from the upper edge.
However, when the evaporation amount of the solvent of the resin material is relatively large, the resin material may be filled up to a state where the resin material is raised from the upper edge of the recess 11a.
The thickness of the first wavelength conversion layer 13 is determined based on the wavelength conversion efficiency of the wavelength conversion material, and is preferably selected to be about 20 to 150 μm.

On the other hand, the second wavelength conversion layer 15 is mixed with the resin material in which the sealing portion 14 is to be formed in the same manner as the first wavelength conversion layer 13, and the concave portion 11a. Filling by potting using a dispenser or the like up to a height position near the upper edge of the substrate, and curing the substrate 11 in an inverted state, the wavelength conversion material settles in the resin material based on gravity. The second wavelength conversion layer 15 is simultaneously formed on the surface together with the upper stage 14b of the sealing portion 14. The second wavelength conversion layer 15 is formed on the sealing portion 14 so as to cover the semiconductor light emitting element 12 in the concave portion 11a. After the upper stage 14b is filled and cured, the second wavelength conversion layer 6 containing a predetermined amount of the particulate wavelength conversion agent is applied by potting or the like into the recessed part 14c formed thereon. Also good. In this case, it is not necessary to cure the substrate 11 in a state where the substrate 11 is turned upside down.

Here, the thickness of the second wavelength conversion layer 15 is such that a wavelength conversion effect can be obtained even when only one layer of wavelength conversion material particles is formed. Although a wavelength conversion effect is obtained between the height positions up to the upper edge of 11a, it is preferably selected to be about 20 to 150 μm.
The horizontal size of the second wavelength conversion layer 15 is selected so that direct light from the semiconductor light emitting element 12 that does not transmit through the first wavelength conversion layer 13 is not emitted to the outside.

Here, the wavelength conversion material for the first wavelength conversion layer 13 and the second wavelength conversion layer 15 is one or more materials that convert a light emission peak longer than the light emission peak wavelength of the semiconductor light emitting element 12. In consideration of color unevenness, the same wavelength conversion materials for the first wavelength conversion layer 13 and the second wavelength conversion layer 15 are generally used.
However, different wavelength conversion materials for the first wavelength conversion layer 13 and the second wavelength conversion layer 15 may be used depending on the physical properties of the constituent materials such as reflectance.

The wavelength conversion material for the first wavelength conversion layer 13 and the second wavelength conversion layer 15 is generally A ₃ B ₅ O ₁₂ : M (A: Y, Gd, Lu, Tb, B: Al, Ga, M: Ce ³⁺ , Tb ³⁺ , Eu ³⁺ , Cr ³⁺ , Nd ³⁺ or Er ³⁺ ), rare earth doped BAM phosphor (barium-aluminum-magnesium compound phosphor), Y ₂ O ₂ S: Eu ³⁺ , ZnS: Sulphide compound phosphors such as Cu, Al or (Sr, Ca) S: Eu ²⁺ , CaGa ₂ S ₄ : Eu ²⁺ and SrGa ₂ S ₄ : Eu ^At least one of thiogallate phosphors doped with rare earth such as ²⁺ , aluminate such as TbAlO ₃ : Ce ³⁺ or orthosilicate such as (Ba, Ca, Eu) _x Si _y O _z : Eu ²⁺ A phosphor containing one composition is included.
Note that, if necessary, a scattering material such as barium sulfate, magnesium oxide, or silicon oxide may be mixed in these materials in order to assist reflection of excitation light and wavelength-converted light.

The semiconductor light emitting device 10 according to the embodiment of the present invention is configured as described above. When a driving voltage is applied to the semiconductor light emitting element 12 through the pair of extraction electrodes 16a and 16b, the semiconductor light emitting element 12 emits light. .
The light L from the semiconductor light emitting element 12 is radiated in all directions, and the light L having the highest excitation intensity that is emitted almost vertically upward in the optical axis direction is the lower stage 14a of the sealing portion 14. From the first wavelength conversion layer 13, without passing through the first wavelength conversion layer 13, a part of the sealing portion 14 is transmitted through the second wavelength conversion layer 15 and the other part is the second wavelength The wavelength is converted by the conversion layer 15 to become the second wavelength light L2 and reflected downward, and the remaining light L is reflected by the second wavelength conversion layer 15 and then incident on the first wavelength conversion layer 13. To do.

  A part of the incident light is reflected by the first wavelength conversion layer 13 and radiates upward, and a part of the light L is wavelength-converted by the first wavelength conversion layer 13 to be first. The wavelength light L1 is emitted upward.

On the other hand, a part of the light emitted from the side surface of the semiconductor light emitting element 12 off the optical axis is reflected by the bottom surface or the side surface of the recess 12a, and the other part is directly the first wavelength conversion layer. 13 is incident. Then, part of the light is wavelength-converted to become the first wavelength light L1, and the other part is transmitted through the first wavelength conversion layer 13 and emitted upward.
Therefore, the first wavelength light L1 and the second wavelength light L2 described above are emitted toward the outside by being mixed with the light L from the semiconductor light emitting element 12.

In this case, as a feature of the present invention, since the first wavelength conversion layer 13 is not provided in the region immediately above the semiconductor light emitting element 12, the light emitted from the semiconductor light emitting element 12 in the optical axis direction has the first wavelength. Since there is no need to transmit through the conversion layer 13, the transmission loss at the time of transmission through the first wavelength conversion layer 13 is eliminated, the light extraction efficiency is improved, and high efficiency can be realized. become.
Further, since the first wavelength conversion layer 13 is disposed above the bottom surface of the recess 11 a of the base 11, all the light emitted from the semiconductor light emitting element 12 to the side is incident on the first wavelength conversion layer 13. Therefore, the light from the semiconductor light emitting element 12 is not directly emitted to the outside, so that the color unevenness between the second wavelength conversion unit 15 and its surroundings can be reduced.
Furthermore, since the upper surface of the first wavelength conversion layer 13 has a substantially parabolic cross section upward, the concentration of the wavelength conversion material decreases toward the center. The light extraction efficiency is improved.

[Experimental Example 1]
An experimental example of the semiconductor light emitting element 10 described above will be described below.
First, as the substrate 11, an insulating ceramic material in which Ag-plated extraction electrodes 16 a and 16 b were wired was prepared.
Then, a metal ring in which an Ag-based alloy is vapor-deposited on the inner surface of the recess 11a (end face angle of about 60 degrees, depth 1000 μm) of the base 11 is electrically connected to the base 11 and the extraction electrodes 16a and 16b. The substrate 11 was brazed while removing the mechanical insulation.
Next, an InGaN-based compound semiconductor (emission wavelength peak: 405 nm, height: 350 μm) formed on the n-type SiC substrate is used as the semiconductor light-emitting element 12 with respect to the extraction electrode 16a corresponding to the cathode electrode formed on the n-type substrate. Then, it was electrically connected with Ag paste and fixed to the base 11, and the lead electrode 16b corresponding to the anode electrode formed on the InGaN-based semiconductor was wire-bonded with Au wire and electrically connected.

10 wt% of BAM blue phosphor + BAM green phosphor + germanium oxide red phosphor prepared as a first wavelength conversion layer 13 so as to be white in a silicone resin with respect to such a substrate 11. The mixed resin material is filled into the concave portion 11a so as to form a substantially parabolic cross section connecting the upper edge of the concave portion 11a and the upper end of the semiconductor light emitting element 12, and the base 11 is turned upside down at 150 ° C. for one hour. The resin material was held and cured, and the phosphors were allowed to settle to form the first wavelength conversion layer 13 and the lower stage 14a of the sealing portion 14.
Thereafter, a transparent silicone resin is filled on the lower stage 14a of the sealing portion 14 in the concave portion 11a up to the vicinity of the upper edge of the concave portion 11a so that the surface thereof is slightly dented, and held at 150 ° C. for 1 hour. The resin was cured to form the upper stage 14b of the sealing part 14 as a spacer part.
Finally, in the concave portion 14c of the upper stage 14b of the sealing portion 14, the above phosphor mixed with 10% by weight of silicone resin is filled and held at 150 ° C. for 1 hour to obtain the second wavelength conversion layer. 15 was formed.

On the other hand, as Comparative Example 1 based on Patent Document 1, a substrate in which the base 11 was cured without being turned upside down when the first wavelength conversion layer 13 was formed was produced.
When the completed Experimental Example 1 and Comparative Example 1 were operated, the chromaticity coordinates of the outgoing light to the outside were both (0.36, 0.38). In addition, the power efficiency (lm / W) and the total luminous flux (lm) are 102% and 103%, respectively, with the total value with Comparative Example 1 as 100%, and the power efficiency and the light extraction efficiency are improved. Was confirmed.

[Example 2]
FIG. 2 shows a configuration of a second embodiment of the semiconductor light emitting device according to the present invention. In FIG. 2, the semiconductor light emitting device 20 has substantially the same configuration as that of the semiconductor light emitting device 10 shown in FIG. 1, and is different only in the following points.
That is, the transparent substrate 21 is disposed immediately above the semiconductor light emitting element 12.
The transparent substrate 21 is made of a transparent material that does not absorb excitation light from the semiconductor light emitting element 12, for example, the same material as the resin material that forms the sealing portion 14.

The transparent substrate 21 is formed on the upper surface of the semiconductor light emitting element 12 by bonding or the like before the first wavelength conversion layer 13 and the lower stage 14a of the sealing portion 14 are formed when the semiconductor light emitting device 20 is manufactured. Is done.
Thereafter, the resin material mixed with the phosphor is filled up to the vicinity of the upper surface of the transparent substrate 21, and the substrate 11 is cured in an inverted state, whereby the lower stage 14a of the first wavelength conversion layer 13 and the sealing portion 14 is obtained. Is formed.
In this case, the formation of the first wavelength conversion layer 13 immediately above the semiconductor light emitting element 12 can be reliably excluded.

[Example 3]
FIG. 3 shows the configuration of the third embodiment of the semiconductor light emitting device according to the present invention. 3, the semiconductor light emitting device 30 is different from the semiconductor light emitting device 10 of FIG. 1 only in the following points.
That is, in the semiconductor light emitting device 30, the substrate portion 11 b and the reflection frame portion 11 c of the base body 11 are integrally formed, and a transparent substrate 31 is provided instead of the sealing portion 14. A first wavelength conversion layer 13 is formed on the lower surface, a second wavelength conversion layer 15 is formed on the upper surface, and a pair of extraction electrodes 16 a and 16 b are formed on the bottom surface of the substrate 11.

  The transparent substrate 31 is formed of a material that does not absorb the excitation light from the semiconductor light emitting element 12 and the light wavelength-converted by the first and second wavelength conversion layers 13 and 15, and preferably the sealing portion 14 and Have the same or lower index of refraction.

Moreover, the said transparent substrate 31 is generally comprised from the parallel plate which can be installed in the recessed part 11a.
The transparent substrate 31 may be larger than the recess 11a, and does not need to be a parallel plate. In this case, the transparent substrate 31 is given a predetermined shape by polishing, heat molding, compression molding or the like before or after the first and second wavelength conversion layers 13 and 15 are formed, or the semiconductor light emitting element 12 is formed. It is also possible to provide a recessed portion or a through hole that covers the surface.
Further, in the illustrated case, the transparent substrate 31 can be fixedly held in the recess 11a by being placed on a step portion 11d provided in the recess 11a. The transparent substrate 31 may be fixed by a fixing claw, caulking or the like in the recess 11a.

The first and second wavelength conversion layers 13 and 15 are formed on the transparent substrate 31 by using a printing technique such as a screen printing method, vapor deposition such as a reactive sputtering method or a resistance heating vapor deposition method, or a sheet shape. This wavelength conversion layer can be prepared and sandwiched between transparent substrates.
In this case, the thickness of the second wavelength conversion layer 15 is selected to be about 50 to 150 μm, for example.

According to the semiconductor light emitting device 30 having such a configuration, the semiconductor light emitting device 10 operates in the same manner as the semiconductor light emitting device 10 shown in FIG. 1 and does not include the sealing portion 14 in the recess 11a. Thus, the filling process and the curing process in the inverted state are not required, and the assembly time can be shortened.
Note that the sealing portion 14 (lower stage 14a) may be filled in the recess 11a below the transparent substrate 31. In this case, the material of the sealing portion 14 is not limited to the above-described resin material because the first wavelength conversion layer 13 does not need to settle, and for example, low-pressure air below atmospheric pressure, N2, Ar, etc. The sealing portion 14 (lower stage 14a) may be formed by sealing a gas such as an inert gas.

[Experiment 2]
An experimental example of the semiconductor light emitting element 10 described above will be described below.
First, as the substrate 11, a resin plate having a high reflectivity, in which Ag-plated extraction electrodes 16a and 16b are wired, was prepared.
The concave portion 11a (depth: 500 μm) of the base body 11 is provided with a step portion 11d at a height of 400 μm from the bottom surface, and has an end surface angle of about 60 degrees below the step portion 11d and above the step portion 11d. The end face angle is formed at about 90 degrees.
Next, an InGaN-based compound semiconductor (emission wavelength peak 470 nm, height 100 μm) formed on the transparent sapphire substrate as the semiconductor light emitting element 12 was fixed to the bottom surface of the recess 11 a of the base 11 with a transparent epoxy resin.
Then, the anode electrode and the cathode electrode formed on the InGaN-based semiconductor were wire-bonded to the corresponding extraction electrodes 16a and 16b with Au wires and electrically connected.

Further, on the lower surface of a quartz glass substrate having a thickness of 100 μm as the transparent substrate 31, a silicone resin mixed with 4 wt% of orthosilicate yellow phosphor was applied by screen printing to a thickness of 20 μm, and 150 ° C. For 1 hour to cure the silicone resin and form the first wavelength conversion layer 13.
Further, on the upper surface of the quartz glass substrate, a silicone resin mixed with 6% by weight of an orthosilicate-based yellow phosphor was applied by screen printing at a thickness of 15 μm, held at 150 ° C. for 1 hour, and second The wavelength conversion layer 15 was formed.
Finally, the transparent substrate 31 is placed in a state where the concave portion 11a is filled with the transparent silicone resin up to the height position near the step portion 11d so that the bubbles do not enter from the end. Excess silicone resin is discharged from a slight gap (not shown) provided between the uppermost edges of the recess 11a and held at 150 ° C. for 1 hour to cure the silicone resin. The transparent substrate 31 was fixed.

  On the other hand, as Comparative Example 2 based on Patent Document 1, in place of the transparent substrate 31, 6 wt% of an orthosilicate yellow phosphor is mixed with an epoxy resin in an area above the step portion 11d of the concave portion 11a. After the phosphor is sufficiently settled, the epoxy resin is cured at 150 ° C. for 1 hour to form the first wavelength conversion layer 13, and then the epoxy is formed in the recess 11 a. The resin was filled with 8% by weight of an orthosilicate-based yellow phosphor, and after sufficiently precipitating the phosphor, it was held at 150 ° C. for 1 hour to produce a cured epoxy resin. .

  When the completed Experimental Example 2 and Comparative Example 2 were operated, the chromaticity coordinates of the outgoing light to the outside were both (0.32, 0.34). In addition, the power efficiency (lm / W) and the total luminous flux (lm) are 102% and 103%, respectively, with the total value with Comparative Example 1 as 100%, and the power efficiency and the light extraction efficiency are improved. Was confirmed.

[Example 4]
FIG. 4 shows the configuration of the fourth embodiment of the semiconductor light emitting device according to the present invention. In FIG. 4, the semiconductor light emitting device 40 has substantially the same configuration as that of the semiconductor light emitting device 10 shown in FIG. 1, and is different only in the following points.
That is, in the semiconductor light emitting device 40, the upper surface of the upper portion 14b of the sealing portion 14 is formed flat and does not include the concave portion 14c.
The second wavelength conversion layer 15 is preferably formed to have a substantially parabolic cross section so as to protrude upward from the upper surface of the upper portion 14b of the sealing portion 14.

  According to the semiconductor light emitting device 40 having such a configuration, the semiconductor light emitting device 10 operates in the same manner as the semiconductor light emitting device 10 shown in FIG. 1 and the upper surface of the second wavelength conversion layer 15 is formed so as to be raised. The total reflection of the light emitted upward from the second wavelength conversion layer 15 can be reduced, and the light extraction efficiency to the outside is improved.

[Example 5]
FIG. 5 shows the configuration of the fifth embodiment of the semiconductor light emitting device according to the present invention. In FIG. 5, the semiconductor light emitting device 50 has substantially the same configuration as that of the semiconductor light emitting device 10 shown in FIG. 1, and is different only in the following points.
That is, in the semiconductor light emitting device 50, the convex transparent member 51 is formed on the upper surface of the upper portion 14 b of the sealing portion 14.
The convex transparent member 51 is provided on the upper surface of the upper part 14b by pasting or the like after the second wavelength conversion layer 15 and the upper part 14b of the sealing part 14 are formed. In this case, the convex transparent member 51 can be made of a transparent resin material constituting the sealing portion 14 or a transparent material containing a high reflectance agent.

  According to the semiconductor light emitting device 50 having such a configuration, the convex transparent member 51 is arranged on the second wavelength conversion layer 15 while acting in the same manner as the semiconductor light emitting device 10 shown in FIG. Therefore, the total reflection of the light emitted upward from the second wavelength conversion layer 15 can be reduced, and the light extraction efficiency to the outside is improved.

[Example 6]
FIG. 6 shows the configuration of a sixth embodiment of the semiconductor light-emitting device according to the present invention. In FIG. 6, the semiconductor light emitting device 60 has substantially the same configuration as that of the semiconductor light emitting device 10 shown in FIG. 1, and is different only in the following points.
That is, in the semiconductor light emitting device 60, the upper surface of the second wavelength conversion layer 15 is formed in a concave shape upward in the recess 14 c on the upper surface of the upper portion 14 b of the sealing portion 14.

  According to the semiconductor light emitting device 60 having such a configuration, the second light converting device 15 operates in the same manner as the semiconductor light emitting device 10 shown in FIG. Total reflection of the light emitted upward from the wavelength conversion layer 15 can be reduced, and the light extraction efficiency to the outside is improved.

[Example 7]
FIG. 7 shows a configuration of a seventh embodiment of the semiconductor light emitting device according to the present invention. In FIG. 7, the semiconductor light emitting device 70 has substantially the same configuration as the semiconductor light emitting device 10 shown in FIG. 1, and is different only in the following points.
In other words, in the semiconductor light emitting device 70, the optical member 71 having a large number of dot-shaped convex portions is formed on the upper surface of the upper portion 14 b of the sealing portion 14.
The optical member 71 is provided on the upper surface of the upper portion 14b by pasting or the like after the second wavelength conversion layer 15 and the upper portion 14b of the sealing portion 14 are formed.
In this case, the optical member 71 can be made of a transparent resin material constituting the sealing portion 14 or a transparent material containing a high reflectivity agent.

  According to the semiconductor light emitting device 50 having such a configuration, the optical member 71 is disposed on the second wavelength conversion layer 15 while acting in the same manner as the semiconductor light emitting device 10 shown in FIG. The total reflection of the light emitted upward from the second wavelength conversion layer 15 can be reduced, and the light extraction efficiency to the outside is improved.

In the embodiment described above, the recess 11a is formed so as to expand upward. However, the present invention is not limited to this, and the side wall of the recess 11a may be perpendicular to the bottom surface.
In the embodiment described above, the semiconductor light emitting element 12 emits blue light from ultraviolet light. However, the semiconductor light emitting element 12 is not limited to this, and may be the compound semiconductor or other compound semiconductor described above. However, any semiconductor light emitting device that emits light within the above emission peak wavelength range can be used within the scope of the present invention, and further includes a semiconductor light emitting device fixed on a submount. it is obvious.

  Furthermore, in the above-described embodiment, the first wavelength conversion layer 13 has a substantially parabolic cross section whose surface is concave upward, based on the surface tension of the resin material, and the base material 11 is top and bottom. In the inverted state, it is formed on the surface of the lower portion 14a of the sealing portion 14 by sedimentation. However, the present invention is not limited to this, and after the lower portion 14a of the sealing portion 14 is molded using a mold. The first wavelength conversion layer 13 may be formed on the surface by vapor deposition or printing.

Further, in the above-described embodiments, in the semiconductor light emitting devices 10, 20, 40, 50, 60, and 70, the first wavelength conversion layer 13 and the lower portion 14a of the sealing portion 14 are formed in the recess 11a, and then the upper surface. Or you may make it install the transparent substrate provided with the 2nd wavelength conversion layer 15 in the lower surface in the recessed part 11a.
Furthermore, after disposing a transparent substrate having the first wavelength conversion layer 13 in the recess 11a as in the semiconductor light emitting device 30, the wavelength conversion material of the second wavelength conversion layer 15 is mixed on the transparent substrate. The second wavelength conversion layer 15 may be formed on the surface of the upper portion 14a of the sealing portion 14 by filling the transparent resin thus prepared and curing it in a state where it is inverted upside down.

  In this way, according to the present invention, with a simple configuration, color unevenness does not occur in the mixed color light of the light emitted from the light emitting element chip and the excitation light by the wavelength conversion agent, and the light extraction efficiency is high. A semiconductor light emitting device and a method for manufacturing the same can be provided.

It is a schematic sectional drawing which shows the structure of 1st embodiment of the semiconductor light-emitting device by this invention. It is a schematic sectional drawing which shows the structure of 2nd embodiment of the semiconductor light-emitting device by this invention. It is a schematic sectional drawing which shows the structure of 3rd embodiment of the semiconductor light-emitting device by this invention. It is a schematic sectional drawing which shows the structure of 4th embodiment of the semiconductor light-emitting device by this invention. It is a schematic sectional drawing which shows the structure of 5th embodiment of the semiconductor light-emitting device by this invention. It is a schematic sectional drawing which shows the structure of 6th embodiment of the semiconductor light-emitting device by this invention. It is a schematic sectional drawing which shows the structure of 7th embodiment of the semiconductor light-emitting device by this invention. It is (A) schematic sectional drawing and (B) schematic plan view which show the structure of an example of the conventional semiconductor light-emitting device.

Explanation of symbols

10, 20, 30, 40, 50, 60, 70 Semiconductor light emitting device 11 Base 11a Recess 11b Substrate 11c Reflective frame 11d Step 12 Semiconductor light emitting element 13 First wavelength conversion layer 14 Sealing portion 14a Lower 14b Upper 14c Concave portion 15 Second wavelength conversion layer 16a, 16b Extraction electrode 21 Transparent substrate 31 Transparent substrate 51 Convex transparent member 71 Dot-shaped optical member

Claims (16)

A semiconductor light emitting device comprising: a base body having a concave portion on the upper surface; a semiconductor light emitting element disposed on the bottom surface of the concave portion; and a wavelength conversion layer for wavelength converting light from the semiconductor light emitting element,
A first wavelength conversion layer disposed excluding the region directly above the semiconductor light emitting element at a height position away from the bottom surface of the recess;
And a second wavelength conversion layer disposed at a height away from the upper surface of the semiconductor light emitting element.   2. The semiconductor light emitting device according to claim 1, further comprising a sealing portion that is filled in the recess and is made of a translucent material that does not absorb light from the semiconductor light emitting element.   3. The semiconductor light emitting device according to claim 1, wherein the first wavelength conversion layer is disposed near a lower surface of a two-stage sealing portion. 4.   4. The semiconductor light emitting device according to claim 1, wherein the second wavelength conversion layer is disposed in the vicinity of the upper surface of the two-stage sealing portion.   5. The semiconductor light emitting device according to claim 1, wherein a transparent substrate penetrating the first wavelength conversion layer is placed immediately above the semiconductor light emitting element. 6.   5. The semiconductor light emitting device according to claim 1, wherein the first wavelength conversion layer is formed on a lower surface of a transparent substrate.   The semiconductor light-emitting device according to claim 1, wherein the second wavelength conversion layer is formed on an upper surface of a transparent substrate.   8. The first wavelength conversion layer according to claim 1, wherein the first wavelength conversion layer has a substantially parabolic cross section that curves upward from the inner edge facing the semiconductor light emitting element toward the radially outer side. The semiconductor light-emitting device described in 1.   9. The semiconductor light emitting device according to claim 1, wherein the upper surface of the sealing portion includes a recess in the vicinity of the center immediately above the semiconductor light emitting element. The first wavelength conversion layer and the second wavelength conversion layer include A ₃ B ₅ O ₁₂ : M (A: Y, Gd, Lu, Tb, B: Al, Ga, M: Ce ³⁺ , Tb ^3+. , Eu ³⁺ , Cr ³⁺ , Nd ³⁺ or Er ³⁺ ), BAM phosphor (barium-aluminum-magnesium compound phosphor doped with rare earth), Y ₂ O ₂ S: Eu ³⁺ or ZnS: Cu Sulfide-based compound phosphors such as Al, Al or thiogallate phosphors doped with rare earth such as (Sr, Ca) S: Eu ²⁺ , CaGa ₂ S ₄ : Eu ²⁺ or SrGa ₂ S ₄ : Eu ²⁺ It includes a phosphor containing at least one composition of aluminate such as TbAlO ₃ : Ce ³⁺ or orthosilicate such as (Ba, Ca, Eu) _x Si _y O _z : Eu ^2+. A semiconductor light-emitting device according to claim 1.   The sealing part is made of an epoxy resin, a silicone resin, a polydimethylsiloxane derivative having an epoxy group, an oxetane resin, an acrylic resin or a resin containing a cycloolefin resin. The semiconductor light-emitting device according to claim 1, wherein the semiconductor light-emitting device is characterized.   A base with a recess on the top surface;
  A semiconductor light emitting element disposed on the bottom surface of the recess;
  A first wavelength conversion layer for wavelength-converting light from the semiconductor light-emitting element, which is disposed excluding the region directly above the semiconductor light-emitting element at a height position away from the bottom surface of the recess;
  Between the first wavelength conversion layer and the bottom of the recess, a first sealing portion for sealing the semiconductor light emitting element;
  A second wavelength conversion layer for wavelength-converting light from the semiconductor light emitting element, which is disposed at a height position away from the upper surface of the semiconductor light emitting element. Including the following steps:
  A first step of mixing a material used for the first sealing portion and a material used for the first wavelength conversion layer;
  A second step of filling the material mixed in the first step into the concave portion up to an intermediate height position;
  A third step of curing the material mixed in the first step with the base turned upside down to form a first sealing portion and a first wavelength conversion layer;   A method of manufacturing a semiconductor light emitting device according to claim 12,
  The semiconductor light emitting device further includes a second sealing portion disposed between the second wavelength conversion layer and the first wavelength conversion layer,
  The method for manufacturing the semiconductor light emitting device further includes the following steps;
  A fourth step of mixing the material used for the second sealing portion and the material used for the second wavelength conversion layer;
  Fifth filling the material mixed in the fourth step above the first sealing portion and the first wavelength conversion layer into the concave portion up to a height position of the upper edge of the concave portion. The process of;
  A sixth step of forming the second sealing portion and the second wavelength conversion layer by curing the material mixed in the fourth step in a state where the base is inverted upside down. Before the second step , the method further includes a seventh step of disposing a transparent base material extending immediately above the semiconductor light emitting element to a height position exceeding the first wavelength conversion layer. The method of manufacturing a semiconductor light emitting device according to claim 12 or 13. After the third step, the method further includes an eighth step of disposing a transparent substrate having a second wavelength conversion layer on the top surface on the first wavelength conversion layer and the first sealing portion. A method for manufacturing a semiconductor light emitting device according to claim 12. The semiconductor light emitting element is disposed in a recess provided on the upper surface of the substrate, and the first wavelength conversion layer is disposed at a height position away from the bottom surface of the recess except for the region directly above the semiconductor light emitting element. A second wavelength conversion layer is disposed at a height away from the upper surface of the semiconductor light emitting device, and the wavelength of the light emitted from the light emitting device chip is converted by the first wavelength conversion layer and the second wavelength conversion layer. A method for manufacturing a semiconductor light-emitting device that emits mixed color light of wavelength-converted light and light from a semiconductor light-emitting element to the outside,
By disposing a transparent substrate in which the first wavelength conversion layer is provided on the lower surface and the second wavelength conversion layer is provided on the upper surface in the recess, the first wavelength conversion layer and the second wavelength conversion layer are disposed. The manufacturing method of the semiconductor light-emitting device characterized by including the step of forming.

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