JP2007258486A - White light emitting diode - Google Patents

White light emitting diode Download PDF

Info

Publication number
JP2007258486A
JP2007258486A JP2006081561A JP2006081561A JP2007258486A JP 2007258486 A JP2007258486 A JP 2007258486A JP 2006081561 A JP2006081561 A JP 2006081561A JP 2006081561 A JP2006081561 A JP 2006081561A JP 2007258486 A JP2007258486 A JP 2007258486A
Authority
JP
Japan
Prior art keywords
phosphor
layer
emitting diode
white light
light emitting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2006081561A
Other languages
Japanese (ja)
Inventor
Kenji Ito
健治 伊藤
Kazuyoshi Tomita
一義 冨田
Hiroshi Ito
伊藤　　博
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Central R&D Labs Inc
Original Assignee
Toyota Central R&D Labs Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toyota Central R&D Labs Inc filed Critical Toyota Central R&D Labs Inc
Priority to JP2006081561A priority Critical patent/JP2007258486A/en
Publication of JP2007258486A publication Critical patent/JP2007258486A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/10—Bump connectors; Manufacturing methods related thereto
    • H01L2224/15—Structure, shape, material or disposition of the bump connectors after the connecting process
    • H01L2224/16—Structure, shape, material or disposition of the bump connectors after the connecting process of an individual bump connector
    • H01L2224/161—Disposition
    • H01L2224/16135—Disposition the bump connector connecting between different semiconductor or solid-state bodies, i.e. chip-to-chip
    • H01L2224/16145—Disposition the bump connector connecting between different semiconductor or solid-state bodies, i.e. chip-to-chip the bodies being stacked
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805—Shape
    • H01L2224/4809—Loop shape
    • H01L2224/48091—Arched
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/481—Disposition
    • H01L2224/48151—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/48221—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/48245—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being metallic
    • H01L2224/48247—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being metallic connecting the wire to a bond pad of the item
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/481—Disposition
    • H01L2224/48151—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/48221—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/48245—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being metallic
    • H01L2224/48257—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being metallic connecting the wire to a die pad of the item
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15—Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/181—Encapsulation

Landscapes

  • Led Device Packages (AREA)
  • Led Devices (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a white light emitting diode which is higher in productivity and more excellent in luminous intensity than the prior art structure. <P>SOLUTION: In the white light emitting diode; a GaN-based LED layer 12 is provided on one surface of a substrate 10, a cathode electrode 12a and an anode electrode 12b are provided to the GaN-based LED layer 12, and a phosphor-contained layer 14 and a reflecting mirror 16 are sequentially provided on the other surface of the substrate 10. The thickness of the phosphor-contained layer 14 is preferably 25-150 μm. The phosphor-contained layer 14 contains preferably a phosphor and a glass-based material having the phosphor dispersed therein. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明は、白色発光ダイオードに関し、特に、共振型の白色発光ダイオードに関する。   The present invention relates to a white light emitting diode, and more particularly to a resonant white light emitting diode.

白色発光ダイオード（以下、「白色ＬＥＤ」ということがある）は、光電変換部であるＬＥＤ部分と、このＬＥＤによって発生した光から白色を得るための補色光発生部（波長変換部）である蛍光体部分とから構成される。例えば、ＬＥＤとして青色ＬＥＤを用い、この青色光によってＹＡＧ蛍光体を励起し黄色の発光を得、青色と黄色との両者を混ぜ合わせることにより白色を得ることができる。そのほかに紫外ＬＥＤを用い、それによって励起される蛍光体から３原色などの発光を得ることにより白色に変換する方法も検討されている。   A white light emitting diode (hereinafter sometimes referred to as a “white LED”) includes an LED portion that is a photoelectric conversion unit and a fluorescent light that is a complementary color light generation unit (wavelength conversion unit) for obtaining white from light generated by the LED. It is composed of body parts. For example, a blue LED is used as the LED, the YAG phosphor is excited by this blue light to obtain yellow light emission, and white can be obtained by mixing both blue and yellow. In addition, a method of converting to white by using an ultraviolet LED and obtaining light emission of three primary colors from a phosphor excited by the ultraviolet LED has been studied.

現状の白色ＬＥＤとしては、主に青色光をダイオードから、黄色光を蛍光体から得ることにより両者の混色として白色光を出力する構造が提案されている（例えば、特許文献１参照）。   As a current white LED, a structure is proposed in which white light is mainly output as a mixed color by obtaining blue light from a diode and yellow light from a phosphor (see, for example, Patent Document 1).

上記構造は、図２に示すように、引出電極２２を有する樹脂ケース２０上に青色ＬＥＤチップ２８が設けられ、その上に透明樹脂２６に分散されたＹＡＧ蛍光体２４が充填されている。青色ＬＥＤの発光のうちの一部は、ＹＡＧ蛍光体２４を励起して黄色発光させて、他の一部はそのまま透過して青色を発光する。そして、外部には、青色と黄色とが混色して白色光が得られる。   In the above structure, as shown in FIG. 2, a blue LED chip 28 is provided on a resin case 20 having an extraction electrode 22, and a YAG phosphor 24 dispersed in a transparent resin 26 is filled thereon. Part of the light emitted from the blue LED excites the YAG phosphor 24 to emit yellow light, and the other part transmits as it is to emit blue light. And outside, blue and yellow are mixed and white light is obtained.

白色ＬＥＤの効率はすでに白熱電球を上回っており、さらに蛍光灯の効率をも上回ることができれば、蛍光灯のＬＥＤへの置き換えも可能となる。そのためにはＬＥＤの電気−光変換効率の向上、蛍光体の光−光変換効率の向上、光の取り出し効率の向上などが課題である。   The efficiency of the white LED is already higher than that of the incandescent lamp, and if the efficiency of the fluorescent lamp can be exceeded, the replacement of the fluorescent lamp with the LED is possible. For that purpose, improvement of the electrical-light conversion efficiency of the LED, improvement of the light-light conversion efficiency of the phosphor, improvement of the light extraction efficiency, and the like are problems.

すなわち、蛍光灯と比較した場合、効率が低いため、より電気光変換効率のよいＬＥＤが求められている。ＬＥＤの発光効率および光の取り出し効率はかなり向上しているが、蛍光体の励起効率（光−光変換効率）を向上させることも必要である。   That is, when compared with a fluorescent lamp, since the efficiency is low, an LED having higher electro-optical conversion efficiency is demanded. Although the light emission efficiency and light extraction efficiency of the LED are considerably improved, it is also necessary to improve the excitation efficiency (light-light conversion efficiency) of the phosphor.

蛍光体の励起方法には透過型（図３）と反射型（図４）とがある。図３は、透過型の例であり、リードフレーム３０上にフリップチップＬＥＤ３２と、蛍光体層３７、紫外線反射層３８、およびガラス基板３９とが積層して設けられている。そして、これらの層が封止樹脂３６中に充填されている。ＬＥＤからの光は、一度だけ蛍光体層３７を通過し、白色光を発する構成となっている。   There are a transmission type (FIG. 3) and a reflection type (FIG. 4) in the excitation method of the phosphor. FIG. 3 shows an example of a transmission type, in which a flip chip LED 32, a phosphor layer 37, an ultraviolet reflection layer 38, and a glass substrate 39 are laminated on a lead frame 30. These layers are filled in the sealing resin 36. Light from the LED passes through the phosphor layer 37 only once and emits white light.

図４は、反射型の例であり、一対の引出電極４２を配線した樹脂ケース４０の凹内面に蛍光体層４４が形成され、上部にはフリップチップＬＥＤ４５、電極パターン４８、紫外線反射膜４９、ガラス基板５０が設けられている。蛍光体層４４とフリップチップＬＥＤ４５等との間の空隙には、樹脂４６または不活性ガスが充填されている。かかる構成もＬＥＤからの光は、一度だけ蛍光体層３７を通過し、白色光を発する構成となっている。   FIG. 4 shows an example of a reflection type, in which a phosphor layer 44 is formed on a concave inner surface of a resin case 40 in which a pair of extraction electrodes 42 is wired, and a flip chip LED 45, an electrode pattern 48, an ultraviolet reflection film 49, A glass substrate 50 is provided. A gap between the phosphor layer 44 and the flip chip LED 45 is filled with a resin 46 or an inert gas. In such a configuration, light from the LED passes through the phosphor layer 37 only once and emits white light.

上記のような従来技術では、反射型のほうが励起強度の高い光を有効に取り出すことが可能であるが、構造が簡単で作製が容易であることから透過型が主に使用されている。透過型の場合、蛍光体の厚さを最適化することにより最も効率的に白色光を取り出すことが可能となる。一方で、反射型では励起強度の高い表面からの蛍光を有効に取り出すことができるため、薄い蛍光体膜厚でより高い輝度を実現することが可能である。しかし、構造が複雑になるという欠点がある。
特開平７−９９３４５ In the prior art as described above, the reflection type can effectively extract light with high excitation intensity, but the transmission type is mainly used because of its simple structure and easy fabrication. In the case of the transmission type, white light can be extracted most efficiently by optimizing the thickness of the phosphor. On the other hand, since the fluorescence from the surface with high excitation intensity can be effectively extracted in the reflection type, higher luminance can be realized with a thin phosphor film thickness. However, there is a drawback that the structure becomes complicated.
JP-A-7-99345

以上から、本発明は、上記従来の課題を解決することを目的とする。すなわち、本発明は、従来構造よりも生産性が高く、発光強度に優れた白色発光ダイオードを提供することを目的とする。   In view of the above, an object of the present invention is to solve the above conventional problems. That is, an object of the present invention is to provide a white light emitting diode having higher productivity than the conventional structure and excellent emission intensity.

上記課題を解決すべく鋭意検討したところ、本発明者らは、下記本発明に想到し、当該課題を解決できることを見出した。すなわち、本発明は、基板の一方の面側にＧａＮ系ＬＥＤ層が設けられ、前記ＧａＮ系ＬＥＤ層にカソード電極およびアノード電極が設けられ、前記基板の他方の面側に蛍光体含有層と反射鏡とが順次設けられていることを特徴とする白色発光ダイオードである。   As a result of intensive studies to solve the above problems, the present inventors have conceived the present invention described below and found that the problems can be solved. That is, according to the present invention, a GaN-based LED layer is provided on one surface side of a substrate, a cathode electrode and an anode electrode are provided on the GaN-based LED layer, and a phosphor-containing layer and a reflection are provided on the other surface side of the substrate. The white light emitting diode is characterized in that a mirror is sequentially provided.

反射鏡の一態様であるアノード電極と他の反射鏡とからなる共振器の形成によりＬＥＤの発する励起光はこの共振器内部に閉じ込められるため、ＬＥＤのチップ直上における光強度は共振器を形成しない場合と比較して高くなる。光強度の高められた共振器内部に蛍光体を挿入することにより、蛍光体の励起強度を向上させることが可能となる。   The excitation light emitted from the LED is confined inside the resonator by forming a resonator composed of an anode electrode and another reflecting mirror, which is one aspect of the reflecting mirror, so that the light intensity directly above the LED chip does not form a resonator. Higher than the case. By inserting the phosphor into the resonator with increased light intensity, the excitation intensity of the phosphor can be improved.

上記の効果により高効率の波長変換が可能になる。また、光強度の増加によって、より薄い蛍光体層によって高い発光強度を得ることが可能になり、蛍光体の使用量を低減することができ、コストの低減につながる。すなわち、生産性が向上するといえる。また、より薄い蛍光体層にできることにより、蛍光体の再吸収による遮蔽効果を低減することができる。励起光源として紫外ＬＥＤを用いた場合は、共振器のミラーの反射率を１に近づけることにより、外部に放射される紫外線を有効に低減することができる。   The above-described effect enables highly efficient wavelength conversion. Further, by increasing the light intensity, it becomes possible to obtain a high light emission intensity with a thinner phosphor layer, the amount of phosphor used can be reduced, and the cost is reduced. That is, it can be said that productivity is improved. In addition, since the phosphor layer can be made thinner, the shielding effect due to reabsorption of the phosphor can be reduced. When an ultraviolet LED is used as the excitation light source, the ultraviolet rays radiated to the outside can be effectively reduced by bringing the reflectance of the mirror of the resonator close to 1.

前記蛍光体含有層の厚みは、２０〜１５０μｍであることが好ましい。２０〜１５０μｍとすることで、良好な発光特性を維持しながら、簡易な構成の白色発光ダイオードを実現することができる。   The thickness of the phosphor-containing layer is preferably 20 to 150 μm. By setting the thickness to 20 to 150 μm, it is possible to realize a white light emitting diode having a simple configuration while maintaining good light emission characteristics.

また、前記蛍光体含有層は、蛍光体とこれを分散保持するガラス系材料とを含むことが好ましい。ガラス系材料を使用することで、蛍光体含有層を平坦化させることが可能となり、その上に形成される反射鏡も平坦化させることができる。   Moreover, it is preferable that the said fluorescent substance containing layer contains fluorescent substance and the glass-type material which carries out dispersion | distribution holding | maintenance. By using the glass-based material, the phosphor-containing layer can be flattened, and the reflecting mirror formed thereon can be flattened.

本発明の白色発光ダイオードは、図１に示すように、基板１０の一方の面側にＧａＮ系ＬＥＤ層１２が設けられ、ＧａＮ系ＬＥＤ層１２上にカソード電極１２ａおよびアノード電極１２ｂが設けられている。また、基板１０の他方の面側には、蛍光体含有層１４と反射鏡１６とが順次設けられている。   As shown in FIG. 1, the white light emitting diode of the present invention has a GaN-based LED layer 12 provided on one surface side of a substrate 10, and a cathode electrode 12 a and an anode electrode 12 b provided on the GaN-based LED layer 12. Yes. A phosphor-containing layer 14 and a reflecting mirror 16 are sequentially provided on the other surface side of the substrate 10.

本発明の白色発光ダイオードは、発光に寄与するＬＥＤおよび蛍光体が、アノード電極１２ｂと反射鏡１６との間に設けられ、アノード電極１２ｂと反射鏡１６とが共振器を形成するための２つの鏡の役割を有している。共振器を構成する２枚の鏡は励起波長の全部あるいは一部を共振器内部に閉じ込めると同時に、蛍光体の発光波長に対しては一方の鏡はすべてを反射し、もう一方（光取り出し側）の鏡はほとんどすべてを透過可能なものとすることが好ましい。   In the white light emitting diode of the present invention, an LED and a phosphor that contribute to light emission are provided between the anode electrode 12b and the reflecting mirror 16, and the anode electrode 12b and the reflecting mirror 16 form two resonators for forming a resonator. Has the role of a mirror. The two mirrors constituting the resonator confine all or part of the excitation wavelength inside the resonator, and at the same time, one mirror reflects all of the emission wavelength of the phosphor and the other (light extraction side) It is preferable that almost all of the mirror) can be transmitted.

ここで、ＬＥＤの発光波長は蛍光体を励起できるものであって、主に青色から紫外の発光を有するものであることが必要である。そのため、ＧａＮ系ＬＥＤが採用される。当該ＧａＮ系ＬＥＤ層１２の厚みは、１〜１０μｍ程度であることが好ましく、２〜６μｍであることがより好ましい。ＧａＮ系ＬＥＤ層１２は公知のＭＯＣＶＤ法により形成することができる。   Here, the light emission wavelength of the LED must be capable of exciting the phosphor, and should mainly emit blue to ultraviolet light. Therefore, GaN-based LEDs are used. The thickness of the GaN-based LED layer 12 is preferably about 1 to 10 μm, and more preferably 2 to 6 μm. The GaN-based LED layer 12 can be formed by a known MOCVD method.

カソード電極１２ａは、Ａｌなどを使用することができる。アノード電極１２ｂは、Ａｇなどを使用することができる。カソード電極１２ａは、電流を供給するためのもので、ｎ型ＧａＮ上でＬＥＤの発光領域の周囲に設けることが好ましい。アノード電極１２ｂは、ｐ型ＧａＮ上で発光領域の全面に渡り設けることが好ましい。これらの電極は、公知の真空蒸着法あるいはスパッタリング法により形成することができる。   Al or the like can be used for the cathode electrode 12a. For the anode electrode 12b, Ag or the like can be used. The cathode electrode 12a is for supplying a current, and is preferably provided around the light emitting region of the LED on the n-type GaN. The anode electrode 12b is preferably provided over the entire surface of the light emitting region on the p-type GaN. These electrodes can be formed by a known vacuum deposition method or sputtering method.

蛍光体含有層１４に含有される蛍光体は、青色から紫外の発光波長によって励起されるとともに、蛍光体の発光あるいはＬＥＤの発光が混ざり合うことによって白色が得られるものであることが必要である。具体的には、ＹＡＧやサイアロンを使用することができる。   The phosphor contained in the phosphor-containing layer 14 needs to be excited by the emission wavelength from blue to ultraviolet and obtain a white color by mixing phosphor emission or LED emission. . Specifically, YAG or sialon can be used.

蛍光体含有層１４中の蛍光体を分散させるマトリックスとしては、エポキシ樹脂やシリコーン樹脂を使用することができるが、蛍光体含有層１４上に平坦な反射鏡を設けることを考慮すると、ＳＯＧ（スピンオングラス）といったガラス系材料を使用することが好ましい。ＳＯＧを使用することで、平坦な蛍光体含有層１４を形成することが可能となり、その上に形成する反射鏡も平坦なものとすることができる。   As a matrix for dispersing the phosphor in the phosphor-containing layer 14, an epoxy resin or a silicone resin can be used. In consideration of providing a flat reflecting mirror on the phosphor-containing layer 14, however, SOG (spin-on) It is preferable to use a glass-based material such as glass. By using SOG, the flat phosphor-containing layer 14 can be formed, and the reflecting mirror formed thereon can be flat.

蛍光体とこれを分散するガラス系材料（例えば、ＳＯＧ）とを含む蛍光体含有層（ＳＯＧ膜）は、シロキサンまたはシリケートを溶剤に混合させてＳＯＧ溶液を調製しこれに蛍光体を添加（例えば、１０〜２０質量％）して、ノズルを通じて基板上にＳＯＧ溶液を滴下して回転塗布（スピンコート）を実施した後、脱水及び凝縮のためにベーク又はキュリング行って、形成することができる。スピンコートの回転数は、１０００〜５０００ｒｐｍとすることが好ましい。   A phosphor-containing layer (SOG film) containing a phosphor and a glass-based material (for example, SOG) in which the phosphor is dispersed is prepared by mixing siloxane or silicate with a solvent to prepare an SOG solution and adding the phosphor to the layer (for example, 10-20% by mass), and a SOG solution is dropped onto a substrate through a nozzle and spin coating is performed, followed by baking or curling for dehydration and condensation. The rotation speed of the spin coat is preferably 1000 to 5000 rpm.

ここで、ＳＯＧは、好ましくは側鎖（side chain）がＣｘＨ２ｘ＋１（ｘは自然数）の結合構造を有する有機シリコン系であり、また、溶剤は、好ましくはエーテル系の溶剤であり、より好ましくはプロピレングリコールジメチルエーテルを使用する。しかし、エーテル系溶剤より性能は良くないがアルコール系の溶剤も使用することができる。 Here, the SOG is preferably an organic silicon type having a bond structure in which the side chain is C x H 2x + 1 (x is a natural number), and the solvent is preferably an ether type solvent. Preferably propylene glycol dimethyl ether is used. However, although the performance is not as good as that of ether solvents, alcohol solvents can also be used.

蛍光体含有層１４の厚みは、２０〜１５０μｍであることが好ましく、４０〜１４０μｍであることがより好ましい。かかる範囲とすることで、良好な発光特性を維持しながら、簡易な構成の白色発光ダイオードを実現することができる。   The thickness of the phosphor-containing layer 14 is preferably 20 to 150 μm, and more preferably 40 to 140 μm. By setting it as such a range, a white light emitting diode having a simple configuration can be realized while maintaining good light emission characteristics.

反射鏡１６は、既述のように、アノード電極１２ｂと共に共振器を構成する。反射鏡１６としては、ＳｉＯ／ＨｆＯ、ＳｉＯ／ＭｇＯ、ＳｉＯ／ＹＯ、ＳｉＯとＴｉＯとを積層した誘電体反射層、ＳｉＯとＺｒＯとを積層した誘電体反射層を用いることが好ましい。反射鏡を構成する各層の厚みは、その屈折率をｎとしたとき、λ／４ｎ（λはＬＥＤの発光波長）となることが好ましい。例えば、誘電体反射層は、それぞれの層を公知のスパッタリングにより、形成することができる。   As described above, the reflecting mirror 16 constitutes a resonator together with the anode electrode 12b. As the reflecting mirror 16, it is preferable to use SiO / HfO, SiO / MgO, SiO / YO, a dielectric reflecting layer in which SiO and TiO are laminated, and a dielectric reflecting layer in which SiO and ZrO are laminated. The thickness of each layer constituting the reflecting mirror is preferably λ / 4n (λ is the emission wavelength of the LED), where n is the refractive index. For example, each of the dielectric reflection layers can be formed by known sputtering.

なお、アノード電極１２ｂを反射鏡とせずに、別途反射鏡を設けてもよい。この場合、反射鏡としては、既述の誘電体反射層や金属を使用することができる。そして、当該反射鏡を設ける場合は、アノード電極１２ｂは、透明電極とすることが好ましく、例えば、ＩＴＯやＺｎＯを使用することができる。   Note that a separate reflecting mirror may be provided without using the anode electrode 12b as a reflecting mirror. In this case, the above-described dielectric reflecting layer or metal can be used as the reflecting mirror. When the reflecting mirror is provided, the anode electrode 12b is preferably a transparent electrode, and for example, ITO or ZnO can be used.

本発明の白色発光ダイオードについて、蛍光体含有層の厚みを変化させて、当該厚みと放射強度との関係を調査した。   Regarding the white light emitting diode of the present invention, the thickness of the phosphor-containing layer was changed, and the relationship between the thickness and the radiation intensity was investigated.

具体的には、図１に示す構成の白色発光ダイオードについて調査した。まず、近紫外域（３８５ｎｍ）で発光する発光ダイオードとして、ＩｎＧａＡｌＮからなるＧａＮ系ＬＥＤ層１２を、両面を鏡面研磨されたサファイヤ基板（厚さ４３０μｍ）１０上に形成した。フォトレジストを用いたパターニングとＩＣＰ（Ｉｎｄｕｃｔｉｖｅ Ｃｏｕｐｌｅｄ Ｐｌａｓｍａ）を用いたＲＩＥによりｎ型ＩｎＧａＡｌＮ層の一部を露出させ、Ａｌからなるカソード電極１２ａを形成した。また、ｐ型ＩｎＧａＡｌＮ表面にアノード電極１２ｂを形成した。ここではアノード電極としてＡｇを用いることにより近紫外光に対して９０％の高い反射率を得ている。これによって、このＡｇ電極は、既に述べた共振器を構成する一端の鏡として作用する。   Specifically, a white light emitting diode having the configuration shown in FIG. 1 was investigated. First, as a light emitting diode emitting light in the near ultraviolet region (385 nm), a GaN-based LED layer 12 made of InGaAlN was formed on a sapphire substrate (thickness: 430 μm) 10 having both surfaces mirror-polished. A part of the n-type InGaAlN layer was exposed by patterning using a photoresist and RIE using ICP (Inductive Coupled Plasma) to form a cathode electrode 12a made of Al. An anode electrode 12b was formed on the p-type InGaAlN surface. Here, by using Ag as the anode electrode, a high reflectance of 90% with respect to near-ultraviolet light is obtained. Thus, this Ag electrode acts as a mirror at one end constituting the resonator already described.

蛍光体（Ｙ２Ｏ２Ｓ：Ｅｕ，（Ｂａ，Ｍｇ）Ａｌ１０Ｏ１７：Ｅｕ，Ｍｎ，（Ｂａ，Ｍｇ）Ａｌ１０Ｏ１７：Ｅｕ）を重量比１：１．３：０．１５で混合しＳＯＧに重量比２０％で混合してサファイヤ基板裏面に塗布し、蛍光体含有層１４を形成した。これによって蛍光体を塗布した層の平坦性を得ることができる。続いてその上にスパッタリングを用いてＳｉＯ（厚さ６５ｎｍ）およびＺｒＯ（厚さ４５ｎｍ）を交互に３周期（それぞれ３層）ほど積層し、反射鏡１６を設けることによって蛍光体の発する可視光の透過率が高く、ＬＥＤの発する近紫外光の反射率の高い鏡を具備する白色発光ダイオードを作製した。 Phosphor (Y 2 O 2 S: Eu, (Ba, Mg) Al 10 O 17 : Eu, Mn, (Ba, Mg) Al 10 O 17 : Eu) in a weight ratio of 1: 1.3: 0.15 The mixture was mixed with SOG at a weight ratio of 20% and applied to the back surface of the sapphire substrate to form the phosphor-containing layer 14. Thereby, the flatness of the layer coated with the phosphor can be obtained. Subsequently, SiO (thickness: 65 nm) and ZrO (thickness: 45 nm) are alternately laminated by about 3 periods (three layers each) by sputtering, and a reflecting mirror 16 is provided to provide visible light emitted from the phosphor. A white light emitting diode including a mirror having high transmittance and high reflectivity of near-ultraviolet light emitted from the LED was manufactured.

図５に、上記白色発光ダイオードの放射強度の蛍光体含有層の厚さ依存性を示す。また、比較として、透過型（図３参照）および反射型（図４参照）の各構造の白色発光ダイオードにおける放射強度の蛍光体層の厚さ依存性を示す。図５より、共振型である本発明の白色発光ダイオードの採用により従来構造よりも薄い蛍光体含有層で最も高い発光強度が得られることが確認できた。   FIG. 5 shows the dependence of the radiation intensity of the white light emitting diode on the thickness of the phosphor-containing layer. Further, as a comparison, the dependence of the radiation intensity on the thickness of the phosphor layer in the white light emitting diodes of the transmissive (see FIG. 3) and reflective (see FIG. 4) structures is shown. From FIG. 5, it was confirmed that the highest emission intensity can be obtained with the phosphor-containing layer thinner than the conventional structure by adopting the resonance type white light emitting diode of the present invention.

本発明の白色発光ダイオードの層構成を示す断面図である。It is sectional drawing which shows the layer structure of the white light emitting diode of this invention. 従来の白色発光ダイオードの層構成を示す断面図である。It is sectional drawing which shows the layer structure of the conventional white light emitting diode. 透過型の白色発光ダイオードの層構成を示す断面図である。It is sectional drawing which shows the layer structure of a transmissive | pervious white light emitting diode. 反射型の白色発光ダイオードの層構成を示す断面図である。It is sectional drawing which shows the layer structure of a reflection type white light emitting diode. 白色発光ダイオードの放射強度の蛍光体含有層の厚さ依存性を示す図である。It is a figure which shows the thickness dependence of the fluorescent substance containing layer of the radiation intensity of a white light emitting diode.

符号の説明Explanation of symbols

１０・・・基板
１２・・・ＧａＮ系ＬＥＤ層
１２ａ・・・カソード電極
１２ｂ・・・アノード電極
１４・・・蛍光体含有層
１６・・・反射鏡 DESCRIPTION OF SYMBOLS 10 ... Board | substrate 12 ... GaN-type LED layer 12a ... Cathode electrode 12b ... Anode electrode 14 ... Phosphor containing layer 16 ... Reflective mirror

Claims (3)

基板の一方の面側にＧａＮ系ＬＥＤ層が設けられ、前記ＧａＮ系ＬＥＤ層にカソード電極およびアノード電極が設けられ、
前記基板の他方の面側に蛍光体含有層と反射鏡とが順次設けられていることを特徴とする白色発光ダイオード。 A GaN-based LED layer is provided on one surface side of the substrate, a cathode electrode and an anode electrode are provided on the GaN-based LED layer,
A white light-emitting diode, wherein a phosphor-containing layer and a reflecting mirror are sequentially provided on the other surface side of the substrate. 前記蛍光体含有層の厚みが、２５〜１５０μｍであることを特徴とする請求項１に記載の白色発光ダイオード。   The white light-emitting diode according to claim 1, wherein the phosphor-containing layer has a thickness of 25 to 150 μm. 前記蛍光体含有層が、蛍光体とこれを分散保持するガラス系材料とを含むことを特徴とする請求項１または２に記載の白色発光ダイオード。   3. The white light emitting diode according to claim 1, wherein the phosphor-containing layer includes a phosphor and a glass-based material that holds the phosphor in a dispersed manner.
JP2006081561A 2006-03-23 2006-03-23 White light emitting diode Pending JP2007258486A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2006081561A JP2007258486A (en) 2006-03-23 2006-03-23 White light emitting diode

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2006081561A JP2007258486A (en) 2006-03-23 2006-03-23 White light emitting diode

Publications (1)

Publication Number Publication Date
JP2007258486A true JP2007258486A (en) 2007-10-04

Family

ID=38632415

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2006081561A Pending JP2007258486A (en) 2006-03-23 2006-03-23 White light emitting diode

Country Status (1)

Country Link
JP (1) JP2007258486A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7939843B2 (en) * 2006-10-26 2011-05-10 Toyoda Gosei Co., Ltd. Light emitting device and high refractive index layer
JP5961740B1 (en) * 2015-04-09 2016-08-02 エルシード株式会社 Optical device and light emitting element
US9537060B2 (en) 2013-03-15 2017-01-03 Samsung Electronics Co., Ltd. Semiconductor light emitting device package

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998054929A2 (en) * 1997-05-27 1998-12-03 Koninklijke Philips Electronics N.V. Uv/blue led-phosphor device with efficient conversion of uv/blue light to visible light
JP2001015817A (en) * 1999-04-26 2001-01-19 Matsushita Electronics Industry Corp Compound light-emitting element, light-emitting diode and manufacture thereof
JP2002141559A (en) * 2000-10-31 2002-05-17 Sanken Electric Co Ltd Light emitting semiconductor chip assembly and light emitting semiconductor lead frame
JP2002203989A (en) * 2000-12-21 2002-07-19 Lumileds Lighting Us Llc Light emitting device and its manufacturing method
JP2002246651A (en) * 2001-02-20 2002-08-30 Hitachi Cable Ltd Light-emitting diode and its manufacturing method
JP2003101074A (en) * 2001-09-26 2003-04-04 Stanley Electric Co Ltd Light-emitting device
JP2003243717A (en) * 2002-02-14 2003-08-29 Matsushita Electric Works Ltd Light emitting device
JP2004134633A (en) * 2002-10-11 2004-04-30 Sharp Corp Lighting device
WO2005101445A1 (en) * 2004-04-15 2005-10-27 Koninklijke Philips Electronics N.V. Electrically controllable color conversion cell
JP2006352085A (en) * 2005-03-14 2006-12-28 Philips Lumileds Lightng Co Llc Wavelength conversion semiconductor light emitting device

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998054929A2 (en) * 1997-05-27 1998-12-03 Koninklijke Philips Electronics N.V. Uv/blue led-phosphor device with efficient conversion of uv/blue light to visible light
JP2001015817A (en) * 1999-04-26 2001-01-19 Matsushita Electronics Industry Corp Compound light-emitting element, light-emitting diode and manufacture thereof
JP2002141559A (en) * 2000-10-31 2002-05-17 Sanken Electric Co Ltd Light emitting semiconductor chip assembly and light emitting semiconductor lead frame
JP2002203989A (en) * 2000-12-21 2002-07-19 Lumileds Lighting Us Llc Light emitting device and its manufacturing method
JP2002246651A (en) * 2001-02-20 2002-08-30 Hitachi Cable Ltd Light-emitting diode and its manufacturing method
JP2003101074A (en) * 2001-09-26 2003-04-04 Stanley Electric Co Ltd Light-emitting device
JP2003243717A (en) * 2002-02-14 2003-08-29 Matsushita Electric Works Ltd Light emitting device
JP2004134633A (en) * 2002-10-11 2004-04-30 Sharp Corp Lighting device
WO2005101445A1 (en) * 2004-04-15 2005-10-27 Koninklijke Philips Electronics N.V. Electrically controllable color conversion cell
JP2006352085A (en) * 2005-03-14 2006-12-28 Philips Lumileds Lightng Co Llc Wavelength conversion semiconductor light emitting device

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7939843B2 (en) * 2006-10-26 2011-05-10 Toyoda Gosei Co., Ltd. Light emitting device and high refractive index layer
US9537060B2 (en) 2013-03-15 2017-01-03 Samsung Electronics Co., Ltd. Semiconductor light emitting device package
JP5961740B1 (en) * 2015-04-09 2016-08-02 エルシード株式会社 Optical device and light emitting element
JP2016201525A (en) * 2015-04-09 2016-12-01 エルシード株式会社 Optical device and light-emitting element
WO2017056660A1 (en) * 2015-04-09 2017-04-06 エルシード株式会社 Optical device and light-emitting element

Similar Documents

Publication Publication Date Title
US7242030B2 (en) Quantum dot/quantum well light emitting diode
JP5044194B2 (en) Light emitting diode module
TWI420147B (en) White light-emitting device using fluorescent fiber
TWI355095B (en) Light emitting devices with enhanced luminous effi
US11411134B2 (en) Light emitting apparatus, method of fabricating light emitting apparatus, and method of emitting light using light emitting apparatus thereof
JP2017027019A (en) Light source device
US20220174795A1 (en) System and method for providing color light sources in proximity to predetermined wavelength conversion structures
JP2015176960A (en) light-emitting device
CN102738330B (en) High-white-light luminous efficiency gallium nitride LED pipe core structure
JP2011523225A (en) LED module
TWI441351B (en) White light emitting diode chip and manufacturing method thereof
JP2011513964A (en) Light emitting diode device
JP2008124168A (en) Semiconductor light emitting device
TWI502776B (en) Light emitting device
KR20070065486A (en) White light emitting device
JP7016037B2 (en) Light emitter and light emitting device
JP2009212275A (en) Backlight source for liquid crystal display device
JP2010021497A (en) Semiconductor light-emitting device
JP2007258486A (en) White light emitting diode
US10758937B2 (en) Phosphor device comprising plural phosphor agents for converting waveband light into plural color lights
TW200836379A (en) Light emitting semiconductor device
KR100721127B1 (en) Light source using dichroic color filter
CN102683547A (en) Light emitting diode packaging structure
JP6058948B2 (en) Optical filter, light source device, lighting device
WO2019061818A1 (en) Wavelength conversion device and light emitting device

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20090113

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20110518

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20110531

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20111004