JP2010263242A - Lighting device - Google Patents

Lighting device Download PDF

Info

Publication number
JP2010263242A
JP2010263242A JP2010178496A JP2010178496A JP2010263242A JP 2010263242 A JP2010263242 A JP 2010263242A JP 2010178496 A JP2010178496 A JP 2010178496A JP 2010178496 A JP2010178496 A JP 2010178496A JP 2010263242 A JP2010263242 A JP 2010263242A
Authority
JP
Japan
Prior art keywords
light
layer
semiconductor light
light emitting
emitting element
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
JP2010178496A
Other languages
Japanese (ja)
Inventor
Masahiro Izumi
昌裕 泉
Tomohiro Sanpei
友広 三瓶
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.)
Toshiba Lighting and Technology Corp
Original Assignee
Toshiba Lighting and Technology Corp
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 Toshiba Lighting and Technology Corp filed Critical Toshiba Lighting and Technology Corp
Priority to JP2010178496A priority Critical patent/JP2010263242A/en
Publication of JP2010263242A publication Critical patent/JP2010263242A/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
    • H01L2224/42—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
    • H01L2224/73—Means for bonding being of different types provided for in two or more of groups H01L2224/10, H01L2224/18, H01L2224/26, H01L2224/34, H01L2224/42, H01L2224/50, H01L2224/63, H01L2224/71
    • H01L2224/732—Location after the connecting process
    • H01L2224/73251—Location after the connecting process on different surfaces
    • H01L2224/73265—Layer and wire connectors
    • 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
    • H01L2924/30—Technical effects
    • H01L2924/301—Electrical effects
    • H01L2924/3025—Electromagnetic shielding

Landscapes

  • Led Device Packages (AREA)
  • Non-Portable Lighting Devices Or Systems Thereof (AREA)
  • Led Devices (AREA)
  • Fastening Of Light Sources Or Lamp Holders (AREA)

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting device in which it is easy to maintain light emission efficiency of a semiconductor light-emitting element and extraction efficiency of light can be improved. <P>SOLUTION: The lighting device includes a metal substrate 2, an insulating layer 5, a conductor 8, a light reflecting layer 4 made of metal, the semiconductor light-emitting element 11 having a semiconductor light-emitting layer 13 on one surface of a light-transmissive element substrate 12, a bonding wire 17, and a light-transmissive sealing member 22. The metal substrate 2 is provided with an element fitting portion 3 in one body. The insulating layer 5 is stacked on the metal substrate 2 except at the element fitting portion 3, and the conductor 8 is provided on the layer 5. The light-reflecting layer 4 having a higher reflection factor than the metal forming the substrate 2 is stacked on the element-fitting portion 3, and the layer 4 has such reflection characteristics that the ratio of a diffuse reflectance to a total light beam reflectance to light having a wavelength of 400 to 740 nm is ≥80. The light-emitting element 11 is die-bonded to the light reflecting layer 4 using a transparent die bonding material. Electrodes 14 and 15 of the light-emitting element 11 and the conductor 8 are connected using the bonding wire 17. The semiconductor light emitting element 11 is sealed with the sealing member 22. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、ＬＥＤ(発光ダイオード)チップ等の半導体発光素子を発光させて照明をする照明装置に関する。   The present invention relates to an illumination device that performs illumination by causing a semiconductor light emitting element such as an LED (light emitting diode) chip to emit light.

従来、プリント基板の上面に実装された複数のＬＥＤを発光させて、面状光源として用いるＬＥＤバックライトが知られている。このＬＥＤバックライトでは、ＬＥＤからの光を拡散する拡散板でプリント基板側に反射される光の利用効率を向上させるために、プリント基板のＬＥＤ実装領域を除く領域に、レジストの上面を覆うアルミ蒸着又は銀蒸着などで形成される反射膜を設けて、拡散板で反射されて戻った光を反射膜で反射させて再び拡散板に入射させて輝度を向上させるようにしている（例えば、特許文献１参照。）。   2. Description of the Related Art Conventionally, LED backlights that emit light from a plurality of LEDs mounted on an upper surface of a printed circuit board and are used as a planar light source are known. In this LED backlight, in order to improve the utilization efficiency of the light reflected to the printed circuit board side by the diffusion plate that diffuses the light from the LED, aluminum that covers the upper surface of the resist in the area excluding the LED mounting area of the printed circuit board. A reflective film formed by vapor deposition or silver vapor deposition is provided, and the light reflected and returned by the diffuser is reflected by the reflective film and incident on the diffuser again to improve the brightness (for example, patents) Reference 1).

従来、例えば縦横に列をなして二次元配列された複数のＬＥＤチップを電気的に接続して、これらのチップを発光させて、面状光源として用いる照明装置が知られている。そして、光源がＬＥＤチップである照明装置では、ＬＥＤが発した熱を外部に放出するために金属ベースドプリント基板が用いられている。このプリント基板は、アルミニウム等の金属板上に絶縁層を積層するとともに、この絶縁層上に導体パターンを設けて形成され、ＬＥＤチップは、絶縁層上にフリップチップ実装又はワイヤボンディングによって実装されている（例えば、特許文献２参照。）。   2. Description of the Related Art Conventionally, for example, there is known an illumination device that is used as a planar light source by electrically connecting a plurality of LED chips that are two-dimensionally arranged in rows and columns to emit light. And in the illuminating device whose light source is an LED chip, the metal based printed circuit board is used in order to discharge | release the heat | fever which LED emitted to the exterior. This printed circuit board is formed by laminating an insulating layer on a metal plate such as aluminum and providing a conductor pattern on this insulating layer, and the LED chip is mounted on the insulating layer by flip chip mounting or wire bonding. (For example, refer to Patent Document 2).

特開２００６−１８９５１９号公報（段落00021−0015、図１−図３）JP 2006-189519 A (paragraphs 00002-0015, FIGS. 1 to 3) 特開２００４−１９３３５７号公報（段落0002、0013、0038、図１−図７）Japanese Patent Laying-Open No. 2004-193357 (paragraphs 0002, 0013, 0038, FIGS. 1 to 7)

ＬＥＤが絶縁物からなるプリント基板のレジストの上面に実装されている特許文献１に記載の照明装置では、点灯時にＬＥＤが発する熱を、プリント基板を通して放出するには難がある。これにより、ＬＥＤの温度が上昇し易いから、ＬＥＤの発光効率を維持し難い。   In the illuminating device described in Patent Document 1 in which the LED is mounted on the upper surface of the resist of the printed circuit board made of an insulator, it is difficult to release the heat generated by the LED during lighting through the printed circuit board. Thereby, since the temperature of LED tends to rise, it is difficult to maintain the luminous efficiency of LED.

更に、特許文献１に記載の照明装置ではＬＥＤがいかなるタイプのものか不明である。ＬＥＤの中には、透光性の素子基板の一面に発光層を設け、この発光層と反対側の素子基板の面をプリント基板等に接着するとともに、発光層にボンディングワイヤをワイヤボンディングにより接続して使用されるチップ状のＬＥＤが知られている。そして、この種のＬＥＤチップでは、発光層から放射された光の一部が素子基板を通って裏側に放出される。この種のＬＥＤチップを特許文献１のＬＥＤに適用することは可能である。しかし、この適用例では、ＬＥＤチップまわりのレジストの上面に蒸着により鏡面に形成されたアルミや銀の反射膜が、ＬＥＤチップの直下に存在せず、ＬＥＤチップの裏側に放出された光の利用効率がよくないので、光の取出し性能を高める上では改善の余地がある。   Furthermore, in the illumination device described in Patent Document 1, it is unclear what type the LED is. In the LED, a light emitting layer is provided on one surface of a light-transmitting element substrate, and the surface of the element substrate opposite to the light emitting layer is bonded to a printed circuit board or the like, and a bonding wire is connected to the light emitting layer by wire bonding. Chip-shaped LEDs used in this manner are known. In this type of LED chip, part of the light emitted from the light emitting layer is emitted to the back side through the element substrate. It is possible to apply this type of LED chip to the LED of Patent Document 1. However, in this application example, the reflective film of aluminum or silver formed on the upper surface of the resist around the LED chip by mirror deposition does not exist directly under the LED chip, and the light emitted to the back side of the LED chip is used. Since the efficiency is not good, there is room for improvement in improving the light extraction performance.

又、特許文献２の記載の照明装置では、ＬＥＤチップとこれからの放熱促進を担う金属板との間に絶縁層が介在されている。絶縁層の厚みは、この絶縁層の両面に位置された金属板と導体パターンとの間の電気絶縁を確保する上で、現状では0.25ｍｍ以上必要であるとされている。絶縁層は金属材料に比較して遥かに熱伝導率が低い。特許文献２に記載のように絶縁層を、熱硬化性樹脂に無機質のフィラーを混ぜて熱伝導率を改善した構成としても、依然として金属材料と比較した場合の熱伝導率が低いことには変わりがない。そのため、ＬＥＤチップの温度上昇を十分に抑制し難く、ＬＥＤチップの発光効率を維持する上では改善の余地がある。   Moreover, in the illuminating device described in Patent Document 2, an insulating layer is interposed between the LED chip and a metal plate responsible for promoting heat dissipation. The thickness of the insulating layer is currently required to be 0.25 mm or more in order to ensure electrical insulation between the metal plate located on both surfaces of the insulating layer and the conductor pattern. The insulating layer has a much lower thermal conductivity than the metal material. Even if the insulating layer is configured to improve the thermal conductivity by mixing an inorganic filler with a thermosetting resin as described in Patent Document 2, the thermal conductivity is still low when compared with a metal material. There is no. Therefore, it is difficult to sufficiently suppress the temperature rise of the LED chip, and there is room for improvement in maintaining the light emission efficiency of the LED chip.

しかも、従来の照明装置は、個々のＬＥＤチップから放出される光の利用が十分ではない。そのため、照明装置全体としての光の取出し効率は、２５ｌｍ/Ｗ〜５０ｌｍ/Ｗ程度と低いものしか得られていない現状にある。   And the conventional illuminating device cannot fully utilize the light discharge | released from each LED chip. For this reason, the light extraction efficiency of the entire lighting device is only as low as about 25 lm / W to 50 lm / W.

本発明の目的は、半導体発光素子の発光効率を維持し易いともに、光の取出し効率を向上できる照明装置を提供することにある。   An object of the present invention is to provide an illumination device that can easily maintain the light emission efficiency of a semiconductor light emitting element and can improve the light extraction efficiency.

請求項１の照明装置は、素子取付け部を一体に有する金属基板と；金属基板に前記素子取付け部を除いて積層された絶縁層と；この絶縁層上に設けられるとともに、端と前記素子取付部との間に前記絶縁層が露出するように設けられた導体と；透光性の素子基板の一面であって前記導体の表面より高くいしされた半導体発光層を有するとともにこの発光層上に電極が設けられた前記素子取付け部に設けられる半導体発光素子と；前記素子取付け部及び前記導体に積層されるとともに前記金属基板をなした金属の反射率よりも高い反射率を有した銀製の光反射層であって、平均表面粗さ0.25μmであって、400nm〜740nmの波長の光の全光線反射率に対する拡散反射率の比を80以上とした前記光反射層と；前記素子基板の他面を前記光反射層に接着して前記半導体発光素子を前記素子取付け部にダイボンドした透光性のダイボンド材と；前記半導体発光素子の電極と前記導体とを接続したボンディングワイヤと；前記半導体発光素子を封止して設けた蛍光体が混入された透光性の封止部材と；
を具備したことを特徴とする。 The lighting device according to claim 1 includes a metal substrate integrally having an element mounting portion; an insulating layer laminated on the metal substrate except for the element mounting portion; provided on the insulating layer; A conductor provided so that the insulating layer is exposed between the first and second portions; and a semiconductor light emitting layer formed on one surface of the translucent element substrate and higher than the surface of the conductor, and on the light emitting layer A semiconductor light emitting device provided in the device mounting portion provided with electrodes; a silver light having a higher reflectance than that of the metal layered on the device mounting portion and the conductor and forming the metal substrate A reflection layer having an average surface roughness of 0.25 μm and a ratio of diffuse reflectance to total light reflectance of light having a wavelength of 400 nm to 740 nm of 80 or more; Adhering the surface to the light reflecting layer A translucent die-bonding material obtained by die-bonding the semiconductor light-emitting element to the element mounting portion; a bonding wire connecting the electrode of the semiconductor light-emitting element and the conductor; and a phosphor provided by sealing the semiconductor light-emitting element A translucent sealing member in which is mixed;
It is characterized by comprising.

請求項１及び以下の各発明で、金属基板は各種の金属材料で形成できるが、熱伝導性に優れたＣｕ（銅）やＡｌ（アルミニウム）及びその合金等を好適に用いることができるとともに、この金属基板の素子取付け部は、絶縁層に覆われない部位を指していて、凸部で形成することが好ましい。絶縁層で覆われた金属基板の部位の厚みは0.25ｍｍ〜0.50ｍｍとすることが好ましく、それにより、前記部位の厚み寸法の精度を向上できるに伴い、導体とこれにワイヤボンディングされたボンディングワイヤとの接合部での接合強度のばらつきが抑制されて、接合の信頼性を向上できる。   In claim 1 and each of the following inventions, the metal substrate can be formed of various metal materials, and Cu (copper), Al (aluminum) and alloys thereof excellent in thermal conductivity can be suitably used, The element mounting portion of the metal substrate points to a portion not covered with the insulating layer, and is preferably formed with a convex portion. The thickness of the portion of the metal substrate covered with the insulating layer is preferably 0.25 mm to 0.50 mm, so that the accuracy of the thickness dimension of the portion can be improved, and the conductor and the bonding wire bonded to the conductor are bonded thereto. Variations in the bonding strength at the bonded portion can be suppressed, and the bonding reliability can be improved.

請求項１及び以下の各発明で、絶縁層にはガラスエポキシ基板を好適に用いることができるとともに、良好な光反射性能を得るために白色を呈する絶縁層を使用することが好ましい。例えば、白色のガラスエポキシ基板からなる絶縁層を用いた場合には、半導体発光素子からその周囲に放出された光を反射できるから、絶縁層での光の吸収が抑制されて、光の取出し効率を高めるのに有効である。   In claim 1 and each of the following inventions, a glass epoxy substrate can be suitably used for the insulating layer, and it is preferable to use an insulating layer exhibiting white in order to obtain good light reflection performance. For example, when an insulating layer made of a white glass epoxy substrate is used, light emitted from the semiconductor light emitting element to the surroundings can be reflected, so that absorption of light in the insulating layer is suppressed and light extraction efficiency is reduced. It is effective to increase

請求項１及び以下の各発明で、導体は、例えばＣｕ（銅）やＡｇ（銀）等の電気伝導率が良い金属からなり、エッチング処理やメッキ処理により設けることができ、これ以外に接着剤を用いて絶縁層上に設けられたものであってもよい。この導体の表面にレジスト層を塗布することもできる。レジスト層で導体を覆った構成では、導体の絶縁性を向上できるとともに、導体の耐マイグレーション性の向上と、導体の酸化等を抑制できる点で好ましい。   In claim 1 and each of the following inventions, the conductor is made of a metal having good electrical conductivity such as Cu (copper) or Ag (silver), and can be provided by an etching process or a plating process. May be provided on the insulating layer. A resist layer can be applied to the surface of the conductor. The configuration in which the conductor is covered with the resist layer is preferable in that the insulation of the conductor can be improved, the migration resistance of the conductor can be improved, and the oxidation of the conductor can be suppressed.

請求項１及び以下の各発明で、半導体発光素子には、例えば青色発光をする青色ＬＥＤチップ、紫外光を発する紫外ＬＥＤチップ等を好適に用いることができる他、青色ＬＥＤチップ、赤色ＬＥＤチップ、緑色ＬＥＤチップのうちの少なくとも二種のＬＥＤチップを組み合わせて用いることも可能である。   In claim 1 and each of the following inventions, for example, a blue LED chip that emits blue light, an ultraviolet LED chip that emits ultraviolet light, or the like can be suitably used as the semiconductor light emitting element, a blue LED chip, a red LED chip, It is also possible to use a combination of at least two of the green LED chips.

請求項１及び以下の各発明で、半導体発光素子等を外気及び湿気から遮断してこの素子の寿命低下を防ぐ透光性の封止部材には、透光性の合成樹脂、例えばエポキシ樹脂、シリコーン樹脂、ウレタン樹脂等を用いることができる他、透明な低融点ガラスを用いることもできる。そして、例えば発光源に青色ＬＥＤチップを用いて白色発光をする照明装置とする場合には、青色の光で励起されて黄色の光を放射する蛍光体が混ぜられた封止部材を用いればよく、或いは紫外光で励起されて赤色の光を放射する蛍光体、紫外光で励起されて緑色の光を放射する蛍光体、及び紫外光で励起されて黄色の光を放射する蛍光体が夫々混ぜられた封止部材を用いればよい。封止部材は、少なくとも一つの半導体発光素子を収容するリフレクタを用いる場合には、このリフレクタの内部に、液状の状態を呈する未硬化の封止部材を注入して固化することで、リフレクタ内の半導体発光素子を封止することができる。又、リフレクタを用いない場合には、半導体発光素子毎、或いは全ての半導体発光素子にわたって液状の状態を呈する未硬化の封止部材をポッティングして、半導体発光素子を封止することができる。   In claim 1 and each of the following inventions, a translucent sealing member that shields a semiconductor light emitting element and the like from the outside air and moisture to prevent a decrease in the lifetime of the element includes a translucent synthetic resin such as an epoxy resin, A silicone resin, a urethane resin, etc. can be used, and transparent low melting glass can also be used. For example, when a lighting device that emits white light using a blue LED chip as a light source is used, a sealing member mixed with a phosphor that is excited by blue light and emits yellow light may be used. Or, a phosphor that emits red light when excited by ultraviolet light, a phosphor that emits green light when excited by ultraviolet light, and a phosphor that emits yellow light when excited by ultraviolet light are mixed. What is necessary is just to use the obtained sealing member. In the case of using a reflector that houses at least one semiconductor light-emitting element, the sealing member is injected with an uncured sealing member that exhibits a liquid state into the reflector to solidify, so that the inside of the reflector. The semiconductor light emitting device can be sealed. When the reflector is not used, the semiconductor light emitting element can be sealed by potting an uncured sealing member that exhibits a liquid state for each semiconductor light emitting element or over all the semiconductor light emitting elements.

請求項１及び以下の各発明で、素子取付け部に半導体発光素子をダイボンドするダイボンド材（接着剤）の厚みは、接着機能を失わない範囲で１０μｍ以下にするとよい。ダイボンド材には、透光性を有したフリットガラスや透光性合成樹脂例えば透明シリコーン樹脂等を用いることができる。   In claim 1 and each of the following inventions, the thickness of the die bond material (adhesive) for die-bonding the semiconductor light-emitting element to the element mounting portion is preferably 10 μm or less as long as the adhesion function is not lost. As the die bond material, a light-transmitting frit glass or a light-transmitting synthetic resin such as a transparent silicone resin can be used.

請求項１及び以下の各発明で、半導体発光素子から素子取付け部への熱伝導を実質的に妨げない金属の光反射層は、例えば無電解メッキにより好適に形成することができ、そのような光反射層として例えばＡｇ（銀）の無電解メッキ層を挙げることができる。   In claim 1 and each of the following inventions, the metal light reflecting layer that does not substantially hinder the heat conduction from the semiconductor light emitting element to the element mounting portion can be suitably formed by, for example, electroless plating. Examples of the light reflecting layer include an electroless plating layer of Ag (silver).

請求項１及び以下の各発明で、全光線反射率とは、以下の通り定義され、拡散反射率及び直線反射率との関係で説明する。直線反射とは図５（Ａ）に模式的に示したように光反射層４に入射した光束Ｌ１が正反射することを指しており、その正反射した光束Ｌ２の光量は、光束Ｌ１の入射点での光の吸収があるために、光束Ｌ１の光量より少ない。そのため、本明細書では光束Ｌ１に対する光束Ｌ２の比を直線反射率と称する。拡散反射とは図５（Ｂ）に模式的に示したように光反射層４に入射した光束Ｌ１がその入射点で吸収された分を除いて入射点を中心として各方面に乱反射することを指している。これら乱反射光は一部に直線反射する光束Ｌ３を含んでいるが、本明細書では、直線反射する光束Ｌ３を除外した残りの光束Ｌ４を拡散反射光と称するとともに、この光束Ｌ４の光束Ｌ１に対する比を本明細書では拡散反射率と称する。したがって、全光線反射率とは、直線反射率と拡散反射率を合計した値を指している。なお、図５（Ａ）の場合には拡散反射率が零であるので、拡散反射率は直線反射率に等しい。   In claim 1 and each of the following inventions, the total light reflectance is defined as follows, and will be described in relation to the diffuse reflectance and the linear reflectance. As schematically shown in FIG. 5A, the linear reflection means that the light beam L1 incident on the light reflecting layer 4 is regularly reflected, and the light amount of the regularly reflected light beam L2 is the incidence of the light beam L1. Since there is light absorption at the point, it is less than the light amount of the light beam L1. Therefore, in this specification, the ratio of the light beam L2 to the light beam L1 is referred to as a linear reflectance. Diffuse reflection means that, as schematically shown in FIG. 5B, the light beam L1 incident on the light reflecting layer 4 is diffusely reflected in various directions around the incident point except for the amount absorbed by the incident point. pointing. These irregularly reflected lights partially include a linearly reflected light beam L3, but in this specification, the remaining light beam L4 excluding the linearly reflected light beam L3 is referred to as diffusely reflected light, and the light beam L4 with respect to the light beam L1. The ratio is referred to herein as diffuse reflectance. Therefore, the total light reflectance refers to a value obtained by adding the linear reflectance and the diffuse reflectance. In the case of FIG. 5A, since the diffuse reflectance is zero, the diffuse reflectance is equal to the linear reflectance.

請求項１の発明の照明装置は、導体及びボンディングワイヤを介して半導体発光素子の半導体発光層に通電することにより、この発光層を発光させ、その光を封止部材に透過させて外部に取出し、その取出し方向の照明を行う。この点灯時、半導体発光層の裏側に放射された光は、透光性の素子基板及びダイボンド材を通って、金属基板をなした金属の反射率よりも高い反射率を有した光反射層に入射して、この光反射層により光の取出し方向に反射される。   In the illumination device of the first aspect of the present invention, the light emitting layer emits light by energizing the semiconductor light emitting layer of the semiconductor light emitting element through the conductor and the bonding wire, and the light is transmitted through the sealing member and taken out to the outside. , Lighting in the take-out direction. At the time of this lighting, the light emitted to the back side of the semiconductor light emitting layer passes through the light-transmitting element substrate and the die bond material to the light reflecting layer having a reflectance higher than that of the metal forming the metal substrate. Incident light is reflected in the light extraction direction by this light reflecting layer.

この場合、400nm〜740nmの波長の光の全光線反射率に対する拡散反射率の比を80以上とした光反射層の反射特性により、光反射層での反射は、正反射される光成分が少なく、光反射層で拡散反射される光成分が多い。これにより、半導体発光素子の半導体発光層の電極直下に位置した部位からこの部位に対して直角となるように裏側に直進して放出された光の内で、光反射層で直線反射されることで、その反射方向に位置した電極で遮光される光量が減るとともに、光反射層で拡散反射されることで、電極に遮られることなく光の取出し方向に反射される光量が増加する。即ち、電極による光の損失が抑制されるので、半導体発光素子から放出された光の取出し効率を向上できる。   In this case, due to the reflection characteristics of the light reflection layer in which the ratio of the diffuse reflectance to the total light reflectance of light having a wavelength of 400 nm to 740 nm is 80 or more, the reflection at the light reflection layer has less light components that are regularly reflected. Many light components are diffusely reflected by the light reflecting layer. As a result, the light reflected from the portion of the semiconductor light emitting element that is located immediately below the electrode of the semiconductor light emitting layer and straightly emitted to the back side so as to be perpendicular to the portion is linearly reflected by the light reflecting layer. Thus, the amount of light shielded by the electrode positioned in the reflection direction is reduced, and the amount of light reflected in the light extraction direction is increased without being blocked by the electrode by being diffusely reflected by the light reflection layer. That is, the loss of light by the electrode is suppressed, so that the extraction efficiency of light emitted from the semiconductor light emitting element can be improved.

又、請求項１の発明の照明装置では、導体と金属基板との間の電気的絶縁を担う絶縁層が、金属基板と半導体発光素子との間に介在されておらず、しかも、半導体発光素子は金属基板と一体の素子取付け部に積層された金属の光反射層に接着してダイボンドされている。そのため、点灯時に半導体発光素子が発する熱は、絶縁層に邪魔されることなく金属基板にダイボンド材及び光反射層を介して直接的に伝導する。この場合、金属で形成されている光反射層は、半導体発光素子から素子取付け部への熱伝導を実質的に妨げない。従って、半導体発光素子の熱が、高効率で金属基板に伝わってこの金属基板から外部に放出されるので、半導体発光素子の温度上昇を効果的に抑制できる。   In the lighting device according to the first aspect of the present invention, the insulating layer responsible for electrical insulation between the conductor and the metal substrate is not interposed between the metal substrate and the semiconductor light emitting device, and the semiconductor light emitting device Is die-bonded to a metal light reflection layer laminated on an element mounting portion integrated with the metal substrate. Therefore, the heat generated by the semiconductor light emitting element during lighting is directly conducted to the metal substrate through the die bond material and the light reflecting layer without being interrupted by the insulating layer. In this case, the light reflecting layer formed of metal does not substantially hinder heat conduction from the semiconductor light emitting element to the element mounting portion. Therefore, the heat of the semiconductor light emitting element is transmitted to the metal substrate with high efficiency and released from the metal substrate, so that the temperature rise of the semiconductor light emitting element can be effectively suppressed.

また、例えばＡｇ製等の光反射層は、460nmの波長の光に対する550nm及び630nmの波長の光の拡散反射率の比を１以上とすることが好ましい。言い換えれば、460nmの青色の光に対する光反射層の拡散反射率と、視感度の向上に貢献する550nmの緑色の光に対する光反射層の拡散反射率との比が１以上であること、並びに460nmの青色の光に対する光反射層の拡散反射率と、演色性の向上に貢献する630nmの赤色の光に対する光反射層の拡散反射率との比が１以上であることを指している。このようにする場合には、以下のように光の取出し効率を向上しつつ、更に好ましい照明ができる。   In addition, for example, a light reflection layer made of Ag or the like preferably has a ratio of diffuse reflectance of light having wavelengths of 550 nm and 630 nm to light having a wavelength of 460 nm of 1 or more. In other words, the ratio of the diffuse reflectance of the light reflecting layer to blue light of 460 nm and the diffuse reflectance of the light reflecting layer to green light of 550 nm that contributes to improving the visibility is 1 or more, and 460 nm. This indicates that the ratio of the diffuse reflectance of the light reflecting layer to blue light and the diffuse reflectance of the light reflecting layer to red light of 630 nm, which contributes to the improvement in color rendering, is 1 or more. In this case, more preferable illumination can be achieved while improving the light extraction efficiency as follows.

また、導体及びボンディングワイヤを介して半導体発光素子の半導体発光層に通電することにより、この発光層を発光させ、発光された460nmの青色の光を封止部材に透過させて外部に取出し、その取出し方向の照明を行う。この点灯時、半導体発光層の裏側に放射された460nmの青色の光は、透光性の素子基板及びダイボンド材を通って、金属基板をなした金属の反射率よりも高い反射率を有した光反射層に入射して、この光反射層により光の取出し方向に反射される。   Further, by energizing the semiconductor light emitting layer of the semiconductor light emitting element through the conductor and the bonding wire, the light emitting layer emits light, and the emitted blue light of 460 nm is transmitted through the sealing member and taken out to the outside. Illuminate in the take-out direction. At the time of lighting, the 460 nm blue light emitted to the back side of the semiconductor light emitting layer has a reflectance higher than that of the metal forming the metal substrate through the translucent element substrate and the die bond material. The light enters the light reflection layer and is reflected by the light reflection layer in the light extraction direction.

この場合、460nmの波長の光の反射率に対する拡散反射率の比を80以上とした光反射層の反射特性により、光反射層での反射は、正反射される光成分が少なく、光反射層で拡散反射される光成分が多い。これにより、半導体発光素子の半導体発光層の電極直下に位置した部位からこの部位に対して直角となるように裏側に直進して放出された青色の光の内で、光反射層で直線反射されることで、その反射方向に位置した電極で遮光される光量が減るとともに、光反射層で拡散反射されることで、電極に遮られることなく光の取出し方向に反射される光量が増加する。即ち、電極による光の損失が抑制されるので、半導体発光素子から放出された光の取出し効率を向上できる。   In this case, due to the reflection characteristics of the light reflection layer in which the ratio of the diffuse reflectance to the reflectance of light having a wavelength of 460 nm is 80 or more, the light reflection layer reflects less light components, and the light reflection layer There are many light components that are diffusely reflected. As a result, the blue light emitted from the portion located immediately below the electrode of the semiconductor light emitting layer of the semiconductor light emitting element and traveling straight to the back side so as to be perpendicular to this portion is linearly reflected by the light reflecting layer. As a result, the amount of light blocked by the electrode positioned in the reflection direction is reduced, and the amount of light reflected in the light extraction direction is increased without being blocked by the electrode by being diffusely reflected by the light reflection layer. That is, the loss of light by the electrode is suppressed, so that the extraction efficiency of light emitted from the semiconductor light emitting element can be improved.

また、本発明の一例の照明装置では、導体と金属基板との間の電気的絶縁を担う絶縁層が、金属基板と半導体発光素子との間に介在されておらず、しかも、半導体発光素子は金属基板と一体の素子取付け部に積層された金属の光反射層に接着してダイボンドされている。そのため、点灯時に半導体発光素子が発する熱は、絶縁層に邪魔されることなく金属基板にダイボンド材及び光反射層を介して直接的に伝導する。この場合、金属で形成されている光反射層は、半導体発光素子から素子取付け部への熱伝導を実質的に妨げない。従って、半導体発光素子の熱が、高効率で金属基板に伝わってこの金属基板から外部に放出されるので、半導体発光素子の温度上昇を効果的に抑制できる。   Moreover, in the illumination device of an example of the present invention, the insulating layer responsible for electrical insulation between the conductor and the metal substrate is not interposed between the metal substrate and the semiconductor light emitting element, and the semiconductor light emitting element is It is die-bonded by bonding to a metal light reflection layer laminated on an element mounting portion integrated with the metal substrate. Therefore, the heat generated by the semiconductor light emitting element during lighting is directly conducted to the metal substrate through the die bond material and the light reflecting layer without being interrupted by the insulating layer. In this case, the light reflecting layer formed of metal does not substantially hinder heat conduction from the semiconductor light emitting element to the element mounting portion. Therefore, the heat of the semiconductor light emitting element is transmitted to the metal substrate with high efficiency and released from the metal substrate, so that the temperature rise of the semiconductor light emitting element can be effectively suppressed.

本発明の照明装置によれば、半導体発光素子の熱を直接的に金属基板に伝えて放出するので、半導体発光素子の温度上昇が抑制され半導体発光素子の発光効率を維持し易いともに、半導体発光層の裏側に放出された光を素子取付け部に積層された光反射層で主に拡散反射させて、半導体発光素子の電極による光の損失を抑制したので、光の取出し効率を向上できる。   According to the lighting device of the present invention, the heat of the semiconductor light emitting element is directly transmitted to the metal substrate and released, so that the temperature rise of the semiconductor light emitting element is suppressed and the light emitting efficiency of the semiconductor light emitting element can be easily maintained, and the semiconductor light emitting Since the light emitted to the back side of the layer is mainly diffusely reflected by the light reflecting layer laminated on the element mounting portion to suppress the light loss due to the electrodes of the semiconductor light emitting element, the light extraction efficiency can be improved.

本発明の一実施形態に係る照明装置を一部切欠いて示す正面図。1 is a front view showing a lighting device according to an embodiment of the present invention with a part cut away. 図１の照明装置の一部を拡大して示す断面図。Sectional drawing which expands and shows a part of illuminating device of FIG. 図２に示された部分を封止部材が除かれた状態で示す正面図。The front view which shows the part shown by FIG. 2 in the state from which the sealing member was removed. 図１の照明装置の金属基板とこれに被着された光反射層の一部を拡大して模式的に示した断面図。Sectional drawing which expanded and showed typically a part of metal substrate of the illuminating device of FIG. 1, and the light reflection layer adhering to this. （Ａ）（Ｂ）は夫々異なる反射形態を説明するために模式的に示した図。(A) and (B) are diagrams schematically illustrating different reflection modes.

図１〜図４を参照して本発明の一実施形態を説明する。   An embodiment of the present invention will be described with reference to FIGS.

図１中符号１はＬＥＤパッケージを形成する照明装置を示している。この照明装置１は、パッケージ基板例えば金属基板２（図２参照）と、光反射層４（図２参照）と、絶縁層５（図２参照）と、複数の導体８と、複数の半導体発光素子１１と、ボンディングワイヤ１７，１８と、リフレクタ２０と、封止部材２２と、を備えて形成されている。   Reference numeral 1 in FIG. 1 denotes an illumination device that forms an LED package. The lighting device 1 includes a package substrate such as a metal substrate 2 (see FIG. 2), a light reflecting layer 4 (see FIG. 2), an insulating layer 5 (see FIG. 2), a plurality of conductors 8, and a plurality of semiconductor light emitting devices. The element 11, the bonding wires 17 and 18, the reflector 20, and the sealing member 22 are formed.

金属基板２は、Ｃｕからなるとともに、照明装置１として必要とされる発光面積を得るために所定形状例えば方形状具体的には長方形状をなしている。金属基板２は、これと一体の凸部からなる素子取付け部３を例えば半導体発光素子１１と同数有している。金属基板２の凸部からなる素子取付け部３は、レーザ光を用いた加工、機械加工等で形成できる他、エッチング処理でも形成できる。   The metal substrate 2 is made of Cu and has a predetermined shape, for example, a rectangular shape, specifically a rectangular shape, in order to obtain a light emitting area required for the lighting device 1. The metal substrate 2 has, for example, the same number of element mounting portions 3 made of convex portions integrated with the metal substrate 2 as the semiconductor light emitting elements 11. The element mounting portion 3 formed of a convex portion of the metal substrate 2 can be formed by processing using laser light, machining, or the like, or can be formed by etching.

なお、本発明は、素子取付け部３に一個の半導体発光素子１１を取付けることに制約されることはなく、一つの素子取付け部３に複数個の半導体発光素子１１を並べて取付けることも可能である。その場合、同じ色を発する複数個の半導体発光素子１１であっても、或いは異なる色を発する複数個の半導体発光素子１１であってもよい。異なる色を発する複数個の半導体発光素子１１を一つの素子取付け部３に取付ける場合には、赤色、黄色、青色の光を発する３個の半導体発光素子１１を並べて取付けることもできる。そして、一つの素子取付け部３に複数個の半導体発光素子１１を並べて取付けた構成においては、照明装置１の全光束を向上させることが可能である。   The present invention is not limited to mounting one semiconductor light emitting element 11 on the element mounting portion 3, and a plurality of semiconductor light emitting elements 11 can be mounted side by side on one element mounting portion 3. . In that case, it may be a plurality of semiconductor light emitting elements 11 emitting the same color, or a plurality of semiconductor light emitting elements 11 emitting different colors. In the case where a plurality of semiconductor light emitting elements 11 emitting different colors are attached to one element attaching portion 3, three semiconductor light emitting elements 11 emitting red, yellow and blue light can be attached side by side. In the configuration in which a plurality of semiconductor light emitting elements 11 are mounted side by side on one element mounting portion 3, the total luminous flux of the lighting device 1 can be improved.

金属基板２の素子取付け部３以外の基板主部２ａ（図２参照）の厚みＡは例えば0.25ｍｍである。素子取付け部３が設けられていない基板主部２ａの裏面２ｂは、大気中に放熱するための放熱面、又は他の放熱部材に面接触する伝熱面として用いられる。   The thickness A of the substrate main portion 2a (see FIG. 2) other than the element mounting portion 3 of the metal substrate 2 is, for example, 0.25 mm. The back surface 2b of the substrate main portion 2a on which the element mounting portion 3 is not provided is used as a heat radiating surface for radiating heat into the atmosphere or a heat transfer surface in surface contact with another heat radiating member.

素子取付け部３は基板主部２ａの表面(一面)に突設されている。図２で代表して示すように素子取付け部３の先端面３ａは前記一面と平行な平坦面をなしている。素子取付け部３はその先端面３ａから金属基板２の一面に至るに従い次第に太く形成されている。言い換えれば、素子取付け部３は、その高さ方向と直交する断面積が先端面３ａから金属基板２の一面に至るに従い次第に大きくなる円錐台状に形成されている。   The element mounting portion 3 is projected from the surface (one surface) of the substrate main portion 2a. As representatively shown in FIG. 2, the tip surface 3a of the element mounting portion 3 forms a flat surface parallel to the one surface. The element mounting portion 3 is gradually formed thicker from the tip end surface 3a to one surface of the metal substrate 2. In other words, the element mounting portion 3 is formed in a truncated cone shape whose cross-sectional area perpendicular to the height direction becomes gradually larger from the tip surface 3 a to one surface of the metal substrate 2.

素子取付け部３の先端面３ａを含む先端部に例えば金属メッキ層よりなる光反射層４が被着されている。光反射層４は、Ａｇの薄膜からなり、その厚みＪは0.003ｍｍ〜0.005ｍｍである。これとともに、Ａｇ製の光反射層４は、金属基板２をなしたＣｕの反射率よりも高い反射率を有して形成され、この光反射層４に入射した光の多くを拡散反射するとともに一部を鏡面反射（正反射とも言う）する反射面をなし、この光反射層４全体の反射率（全光線反射率とも言う）は９０％以上である。なお、拡散反射率が８０％以上であるＡｇの光反射層４の全光線反射率は、例えば酸化アルミニウム等の白色粉末を混入して成形した白色系合成樹脂の反射率と同程度である。   A light reflecting layer 4 made of, for example, a metal plating layer is attached to the tip portion including the tip surface 3a of the element mounting portion 3. The light reflecting layer 4 is made of an Ag thin film, and its thickness J is 0.003 mm to 0.005 mm. At the same time, the light reflecting layer 4 made of Ag is formed to have a reflectance higher than that of Cu forming the metal substrate 2, and diffusely reflects most of the light incident on the light reflecting layer 4. A part of the reflection surface is specularly reflected (also referred to as regular reflection), and the reflectance of the entire light reflection layer 4 (also referred to as total light reflectance) is 90% or more. The total light reflectance of the Ag light reflecting layer 4 having a diffuse reflectance of 80% or more is approximately the same as the reflectance of a white synthetic resin formed by mixing a white powder such as aluminum oxide.

Ａｇ製の光反射層４の反射特性は、400nm〜740nmの波長の光の全光線反射率に対する拡散反射率の比率）が８０以上好ましくは９０以上となるように設定されている。表１に光反射層４の反射特性を示す。この表１では、400nm〜740nmの全区間の平均及び360ｎｍ〜740nmの各波長の光について、夫々全光線反射率と、その内訳である拡散反射率及び直線反射率と、反率（全光線反射率に対する拡散反射率の比率）との関係を示した。なお、この表１での光反射層４は後述のようにＡｇの無電解メッキ層からなる。   The reflection characteristics of the Ag light reflection layer 4 are set such that the ratio of the diffuse reflectance to the total light reflectance of light having a wavelength of 400 nm to 740 nm is 80 or more, preferably 90 or more. Table 1 shows the reflection characteristics of the light reflecting layer 4. In Table 1, for the light of each wavelength of 360 nm to 740 nm, the total light reflectance, the diffuse reflectance and the linear reflectance, and the reciprocity (total light reflection) for the average of all the wavelengths from 400 nm to 740 nm and the wavelengths of 360 nm to 740 nm, respectively. The ratio of the diffuse reflectance to the ratio) was shown. The light reflecting layer 4 in Table 1 is composed of an electroless plating layer of Ag as will be described later.

Figure 2010263242
Figure 2010263242

光反射層４の平均表面粗さは0.25μｍ以上である。ここに、表面粗さは、光反射層４の面の肌の算術平均粗さ（Ｒａ）を指している。0.25μｍ以上のＲａを得るために、光反射層４は、Ａｇを無電解メッキ（置換型メッキ）で素子取付け部３の先端部に生成されたメッキ層で形成されている。ここに無電解メッキとは、イオン化傾向を利用した電位差置換による浸漬メッキを指している。即ち、この無電解メッキでは、素子取付け部３の先端部が浸漬された処理液の酸により、素子取付け部３をなした金属、即ち、銅（Ｃｕ）が溶解されるに伴い、処理液中のＡｇが電位差によってＣｕと置換されることで、素子取付け部３の先端部の表面にＡｇの被膜を析出させる。こうして形成されたＡｇの被膜（光反射層４）は、処理液中のＡｇが次々に処理液中に溶解されるＣｕと置換して生成されるので、図４で模式的に示したように恰もＡｇの粒子（図５中符号Ａｇで示す）が重なり合って密集した状態に形成される。そのため、光反射層４の表面（光反射面）４ａは、微視的にみれば、Ａｇ粒子の大きさに依存した凹凸をなしている。これにより、光反射層４の表面４ａに0.25μｍ以上の平均表面粗さを得て、この光反射層４が主に拡散反射をするように形成されている。   The average surface roughness of the light reflecting layer 4 is 0.25 μm or more. Here, the surface roughness refers to the arithmetic average roughness (Ra) of the skin of the surface of the light reflecting layer 4. In order to obtain Ra of 0.25 μm or more, the light reflecting layer 4 is formed of a plating layer formed at the tip of the element mounting portion 3 by electroless plating (substitution plating) of Ag. Here, the electroless plating refers to immersion plating by potential difference replacement using an ionization tendency. That is, in this electroless plating, as the metal forming the element mounting portion 3, that is, copper (Cu) is dissolved by the acid of the processing liquid in which the tip of the element mounting portion 3 is immersed, Is replaced with Cu by a potential difference, thereby depositing an Ag coating on the surface of the tip of the element mounting portion 3. Since the Ag coating (light reflecting layer 4) formed in this way is formed by replacing Ag in the treatment liquid with Cu dissolved in the treatment liquid one after another, as schematically shown in FIG. The soot is also formed in a dense state in which Ag particles (indicated by Ag in FIG. 5) overlap each other. Therefore, the surface (light reflecting surface) 4a of the light reflecting layer 4 has irregularities depending on the size of the Ag particles when viewed microscopically. Thus, an average surface roughness of 0.25 μm or more is obtained on the surface 4a of the light reflecting layer 4, and the light reflecting layer 4 is formed so as to mainly diffusely reflect.

分光測色計を用いて鏡面反射光（正反射光とも言う）を含むモード（ＳＣＩモード）で測定資料であるＡｇの光反射層４の反射率を測定した値は「全光線反射率」と称され、鏡面反射光（正反射光）を除去したモード（ＳＣＥモード）で測定資料であるＡｇの光反射層４の反射率を測定した値は「拡散反射率」と称されており、そして、全光線反射率から拡散反射率を引いた値は「鏡面反射率（直線反射率とも言う）」と称されている。このため、例えば光反射層４全体の全光線反射率が９０％で、この全光線反射率に対する拡散反射率の比が８０とは、光反射層４の反射率９０％の内訳が、拡散反射率８０％、直線反射率１０％であることを指している。   Using a spectrocolorimeter, the reflectance of the light reflection layer 4 of Ag, which is a measurement material, in a mode (SCI mode) including specular reflection light (also called specular reflection light) is “total light reflectance”. The value obtained by measuring the reflectance of the light reflection layer 4 of Ag, which is a measurement material, in a mode (SCE mode) in which specular reflection light (regular reflection light) is removed is referred to as “diffuse reflectance”, and The value obtained by subtracting the diffuse reflectance from the total light reflectance is referred to as “specular reflectance (also referred to as linear reflectance)”. Therefore, for example, the total light reflectance of the entire light reflection layer 4 is 90%, and the ratio of the diffuse reflectance to the total light reflectance is 80. The breakdown of the reflectance 90% of the light reflection layer 4 is diffuse reflection. The rate is 80% and the linear reflectance is 10%.

光反射層４を含めた素子取付け部３の先端面の高さは、図２において半導体発光素子１１の上面の高さ位置が導体８の高さ位置以上になることを満たせば、基板主部２ａの厚みＡより低くても差し支えないが、基板主部２ａの厚みＡと同じかそれ以上の高さとすることが好ましく、本実施形態では絶縁層５及び導体８の合計厚みより高くしてある。   If the height of the tip surface of the element mounting portion 3 including the light reflecting layer 4 satisfies that the height position of the upper surface of the semiconductor light emitting element 11 is equal to or higher than the height position of the conductor 8 in FIG. Although it may be smaller than the thickness A of 2a, it is preferably set to a height equal to or higher than the thickness A of the substrate main portion 2a. In this embodiment, the thickness is higher than the total thickness of the insulating layer 5 and the conductor 8. .

絶縁層５には光反射性能を得るために例えば白色のガラスエポキシ基板が用いられている。絶縁層５の厚みＢは、最小で0.060ｍｍあればよく、本実施形態では例えば0.25ｍｍにしてある。この絶縁層５は、図２及び図３で代表して示すように素子取付け部３が通る逃げ孔６を有している。この逃げ孔６は例えば円形で、その直径は素子取付け部３の最大径をなす根元部の直径より大きい。逃げ孔６は素子取付け部３と同数設けられている。なお、本実施例では絶縁層５を一層としたが、これは二層とすることもでき、例えば前記最小厚みである場合でも、厚み0.030ｍｍのガラスエポキシ基板を二枚積層したものを用いることが可能であり、それにより、一層のものよりも高い絶縁耐圧を確保できる。   For example, a white glass epoxy substrate is used for the insulating layer 5 in order to obtain light reflection performance. The thickness B of the insulating layer 5 may be 0.060 mm at the minimum, and is set to, for example, 0.25 mm in this embodiment. The insulating layer 5 has an escape hole 6 through which the element mounting portion 3 passes, as representatively shown in FIGS. 2 and 3. The escape hole 6 is circular, for example, and the diameter thereof is larger than the diameter of the root portion forming the maximum diameter of the element mounting portion 3. The same number of escape holes 6 as the element mounting portions 3 are provided. In this embodiment, the insulating layer 5 is a single layer. However, this may be a double layer. For example, even when the thickness is the minimum thickness, a laminate of two glass epoxy substrates having a thickness of 0.030 mm is used. This can ensure a higher withstand voltage than a single layer.

絶縁層５は基板主部２ａの表面(一面)に接着剤７（図２参照）を用いて貼り合わせることにより金属基板２に積層されている。接着剤７は、絶縁性であって、絶縁層５と基板主部２ａとの間に例えば0.005ｍｍ以下の膜厚Ｃで設けられる。絶縁層５の接着において、絶縁層５の各逃げ孔６は各素子取付け部３に夫々嵌合するので、絶縁層５は金属基板２に素子取付け部３を除いて積層され、それにより、素子取付け部３は逃げ孔６に露出されている。   The insulating layer 5 is laminated on the metal substrate 2 by being bonded to the surface (one surface) of the substrate main portion 2a using an adhesive 7 (see FIG. 2). The adhesive 7 is insulative and is provided with a film thickness C of, for example, 0.005 mm or less between the insulating layer 5 and the substrate main portion 2a. In adhesion of the insulating layer 5, each escape hole 6 of the insulating layer 5 is fitted into each element mounting portion 3, so that the insulating layer 5 is laminated on the metal substrate 2 except for the element mounting portion 3. The attachment portion 3 is exposed in the escape hole 6.

前記嵌合により、素子取付け部３をスペーサとして、絶縁層５が金属基板２に対して浮くようなことがなく、絶縁層５が素子取付け部３に適正に重ね合わされるとともに、金属基板２に対し絶縁層５が位置決めされる。言い換えれば、凸部からなる素子取付け部３が通る絶縁層５の逃げ孔６によって、金属基板２へ絶縁層５を接着する際に、この絶縁層５が素子取付け部３に当たらないようにして、金属基板２に絶縁層５を適正に積層させることができる。   By the fitting, the element mounting portion 3 is used as a spacer, the insulating layer 5 does not float with respect to the metal substrate 2, and the insulating layer 5 is appropriately superimposed on the element mounting portion 3, and On the other hand, the insulating layer 5 is positioned. In other words, when the insulating layer 5 is bonded to the metal substrate 2 by the escape hole 6 of the insulating layer 5 through which the element mounting portion 3 made of a convex portion passes, the insulating layer 5 is prevented from hitting the element mounting portion 3. The insulating layer 5 can be appropriately laminated on the metal substrate 2.

そして、前記貼り合わせにおいて接着剤７の塗布量が多く余剰を生じた場合、その余剰分７ａ(図２及び図３参照)の一部は逃げ孔６に流入し、より正確には、素子取付け部３の形状に起因して、この素子取付け部３の周面と逃げ孔６との間に必然的に形成される環状の隙間に、余剰分７ａが流入してそこに溜まって固化される。それにより、絶縁層５は素子取付け部３の周面に対しても接着されるので、積層強度が高められる。しかも、余剰分７ａは体積固有抵抗が１０−２〜１０−１５Ω・ｍの絶縁層として機能するので、後述のように導体８が装着された絶縁層５と素子取付け部３の周面との間の耐電圧を向上できる。なお、接着剤７が乳白色ないしは白色である場合には、半導体発光素子１１からその周囲に放射された光を、逃げ孔６に溜められた接着剤７の余剰分７ａによって光の取出し方向に反射させて、光の取出し効率を高めるのに寄与できる。   And when the application amount of the adhesive 7 is large in the bonding, a part of the surplus 7a (see FIGS. 2 and 3) flows into the escape hole 6, and more precisely, the element mounting Due to the shape of the portion 3, the surplus 7 a flows into the annular gap inevitably formed between the peripheral surface of the element mounting portion 3 and the escape hole 6, and accumulates and solidifies there. . As a result, the insulating layer 5 is also bonded to the peripheral surface of the element mounting portion 3, so that the lamination strength is increased. Moreover, since the surplus portion 7a functions as an insulating layer having a volume resistivity of 10-2 to 10-15 Ω · m, the insulating layer 5 on which the conductor 8 is mounted and the peripheral surface of the element mounting portion 3 as described later. The withstand voltage can be improved. When the adhesive 7 is milky white or white, the light emitted from the semiconductor light emitting element 11 to the periphery thereof is reflected in the light extraction direction by the excess 7a of the adhesive 7 accumulated in the escape hole 6. This can contribute to increasing the light extraction efficiency.

複数の導体８は、各半導体発光素子１１への通電要素としてこれら半導体発光素子１１を直列に接続するために設けられ、絶縁層５の基板主部２ａに接着された裏面とは反対側の面にエッチング処理等により形成されている。これらの導体８は、Ｃｕからなり、絶縁層５を基板主部２ａに貼り合わせる前に設けられる。図１に示すように各導体８は、絶縁層５の長手方向に所定間隔毎に点在して二列形成されている。各列での複数の導体８は例えば４ｍｍピッチで各逃げ孔６と交互に並べられている。これら列の一端側に位置した導体８には電線接続部９（図１参照）が一体に連続して形成されている。これら電線接続部９の夫々には図示しない電源にいたる電線が個別に半田付けされる。   The plurality of conductors 8 are provided to connect the semiconductor light emitting elements 11 in series as current-carrying elements to the semiconductor light emitting elements 11, and are opposite to the back surface bonded to the substrate main portion 2a of the insulating layer 5. It is formed by an etching process or the like. These conductors 8 are made of Cu, and are provided before the insulating layer 5 is bonded to the substrate main portion 2a. As shown in FIG. 1, the conductors 8 are formed in two rows at intervals of a predetermined interval in the longitudinal direction of the insulating layer 5. The plurality of conductors 8 in each row are alternately arranged with each escape hole 6 at a pitch of 4 mm, for example. An electric wire connecting portion 9 (see FIG. 1) is integrally and continuously formed on the conductor 8 located on one end side of these rows. Each of these electric wire connecting portions 9 is individually soldered with electric wires leading to a power source (not shown).

図２及び図３で代表して示すように各導体８は、逃げ孔６の縁には達しておらず、この逃げ孔６の縁から所定距離隔てられている。それにより、導体８の端８ａとこれに最も近接している逃げ孔６の縁との間に、白色の絶縁層５の一部が露出されている。この露出面を図３中に符号５ａで露出面を示す。そのため、導体８の端８ａと素子取付け部３との間に前記環状の隙間より大きい絶縁距離を確保することができるとともに、露出面５ａでもそこに入射した光を光の取出し方向に反射させることができる。   As representatively shown in FIGS. 2 and 3, each conductor 8 does not reach the edge of the escape hole 6 but is separated from the edge of the escape hole 6 by a predetermined distance. Thereby, a part of the white insulating layer 5 is exposed between the end 8a of the conductor 8 and the edge of the escape hole 6 closest to the end 8a. This exposed surface is indicated by reference numeral 5a in FIG. Therefore, an insulation distance larger than the annular gap can be ensured between the end 8a of the conductor 8 and the element mounting portion 3, and light incident on the exposed surface 5a is reflected in the light extraction direction. Can do.

導体８の端８ａは、半導体発光素子１１の後述する電極１４又は１５から0.25ｍｍ〜6.0ｍｍの距離Ｄを隔てて位置される。これは、後述のワイヤボンディングにおいて導体８に対しては、その端８ａをボンディングマシンに認識させて、そこを基準に所定距離Ｅ離れた位置にボンディングワイヤを接合するので、その際にボンディングワイヤの接合部にストレスが残留することを極力抑制するための配慮である。   The end 8a of the conductor 8 is located at a distance D of 0.25 mm to 6.0 mm from an electrode 14 or 15 described later of the semiconductor light emitting element 11. This is because, in the wire bonding described later, the end 8a of the conductor 8 is recognized by the bonding machine, and the bonding wire is bonded to a position separated by a predetermined distance E with reference to the end 8a. This is a consideration for suppressing the residual stress at the joint as much as possible.

各導体８の表面にはＡｇの光反射層１０が被着されている。光反射層１０は導体８の端８ａにも被着されている。この光反射層１０は、反射率が９０％以上のＡｇの薄膜からなり、その厚みは0.003ｍｍ〜0.005ｍｍである。光反射層１０を含めた導体８の厚みＧは0.012ｍｍ〜0.018ｍｍである。各導体８上の光反射層１０は無電解メッキの層で形成されている。この光反射層１０は各素子取付け部３に対する光反射層４の形成と同時に無電解メッキにより設けることができる。なお、光反射層１０の表面にレジスト膜を積層することも可能である。   An Ag light reflecting layer 10 is deposited on the surface of each conductor 8. The light reflecting layer 10 is also attached to the end 8 a of the conductor 8. The light reflecting layer 10 is made of an Ag thin film having a reflectance of 90% or more, and has a thickness of 0.003 mm to 0.005 mm. The thickness G of the conductor 8 including the light reflection layer 10 is 0.012 mm to 0.018 mm. The light reflecting layer 10 on each conductor 8 is formed of an electroless plating layer. The light reflecting layer 10 can be provided by electroless plating simultaneously with the formation of the light reflecting layer 4 for each element mounting portion 3. A resist film can be laminated on the surface of the light reflecting layer 10.

各半導体発光素子１１は例えば青色ＬＥＤチップからなる。このＬＥＤチップは、例えば窒化物半導体を用いてなるダブルワイヤー型であって、図２に示すように透光性を有する素子基板１２の一面に半導体発光層１３を積層して形成されている。素子基板１２は例えばサファイア基板で作られている。半導体発光層１３が有した図示しないｎ形半導体層上にはｎ側電極１４が設けられ、同様に半導体発光層１３が有した図示しないｐ形半導体層上にはｐ側電極１５が設けられている。電極１４，１５はＡｕ製である。これらの電極１４，１５の合計面積は、半導体発光素子１１の正面の面積の１割〜２割を占めており、例えば、半導体発光素子１１の縦横寸法が240μｍ、450μｍである場合、電極１４，１５の大きさは夫々直径100μｍである。半導体発光層１３は、反射膜を有しておらず、したがって、半導体発光素子１１の厚み方向の双方に光を放射できるとともに、素子基板１２の側面から側方へも光を放射できる。   Each semiconductor light emitting element 11 is made of, for example, a blue LED chip. This LED chip is a double-wire type using, for example, a nitride semiconductor, and is formed by laminating a semiconductor light emitting layer 13 on one surface of a light-transmitting element substrate 12 as shown in FIG. The element substrate 12 is made of, for example, a sapphire substrate. An n-side electrode 14 is provided on an n-type semiconductor layer (not shown) included in the semiconductor light emitting layer 13, and a p-side electrode 15 is provided on a p-type semiconductor layer (not shown) included in the semiconductor light emitting layer 13. Yes. The electrodes 14 and 15 are made of Au. The total area of these electrodes 14 and 15 occupies 10% to 20% of the front surface area of the semiconductor light emitting element 11. For example, when the vertical and horizontal dimensions of the semiconductor light emitting element 11 are 240 μm and 450 μm, Each of the sizes 15 has a diameter of 100 μm. The semiconductor light emitting layer 13 does not have a reflective film, and therefore can emit light both in the thickness direction of the semiconductor light emitting element 11 and can also emit light from the side surface of the element substrate 12 to the side.

これらの半導体発光素子１１は、素子基板１２の前記一面と平行な他面を接着剤例えば透光性のシリコーン樹脂からなるダイボンド材１６を用いて各素子取付け部３の光反射層４上にダイボンドされている。それによって、各半導体発光素子１１は、各導体８と同じく例えば４ｍｍピッチで、これら導体８と交互に配置されている。   These semiconductor light-emitting elements 11 are die-bonded on the light-reflecting layer 4 of each element mounting portion 3 on the other surface parallel to the one surface of the element substrate 12 by using a die-bonding material 16 made of an adhesive such as a translucent silicone resin. Has been. Accordingly, the respective semiconductor light emitting elements 11 are arranged alternately with these conductors 8 at a pitch of 4 mm, for example, like the respective conductors 8.

ダイボンド材１６の厚みＨは0.10ｍｍ以下である。ダイボンド材１６は半導体発光素子１１から素子取付け部３への伝熱の抵抗部材となるが、以上のようにきわめて薄いので、このダイボンド材１６での熱抵抗は実質的に無視できる程度である。ダイボンド材１６の厚みＨは、接着性能を失わない範囲でできるだけ薄くすることが望ましい。   The thickness H of the die bond material 16 is 0.10 mm or less. The die bond material 16 serves as a resistance member for heat transfer from the semiconductor light emitting element 11 to the element mounting portion 3. However, since the die bond material 16 is extremely thin as described above, the thermal resistance of the die bond material 16 is substantially negligible. It is desirable that the thickness H of the die bond material 16 be as thin as possible without losing the bonding performance.

半導体発光素子１１の半導体発光層１３と素子取付け部３との間の絶縁耐圧は、ダイボンド材１６だけではなく、このダイボンド材１６よりもはるかに厚いサファイア製の素子基板１２で確保されている。ダイボンド材１６を含めた半導体発光素子１１の厚みＩは例えば0.09ｍｍである。こうした半導体発光素子１１を用いることによって、半導体発光層１３は導体８表面の光反射層１０より高く位置されており、しかも、本実施形態では半導体発光素子１１全体が導体８表面の光反射層１０より高く位置されている。   The withstand voltage between the semiconductor light emitting layer 13 of the semiconductor light emitting element 11 and the element mounting portion 3 is secured not only by the die bond material 16 but also by the element substrate 12 made of sapphire much thicker than the die bond material 16. The thickness I of the semiconductor light emitting element 11 including the die bond material 16 is 0.09 mm, for example. By using such a semiconductor light emitting element 11, the semiconductor light emitting layer 13 is positioned higher than the light reflecting layer 10 on the surface of the conductor 8. In addition, in this embodiment, the entire semiconductor light emitting element 11 is the light reflecting layer 10 on the surface of the conductor 8. Is positioned higher.

こうした高さの差によって、後述のワイヤボンディングにおいて、ボンディングマシンでボンディングワイヤの一端を半導体発光層１３の電極１４，１５にボールボンディングにより接合した後に、このボンディングワイヤの他端を導体８に接合する際、ボンディングマシンのボンディングツールの移動に絶縁層５が邪魔になり難く、又、ボンディングワイヤを斜め下方に無理に引くこともないので、ワイヤボンディングがし易い。   Due to the difference in height, in wire bonding described later, one end of the bonding wire is bonded to the electrodes 14 and 15 of the semiconductor light emitting layer 13 by ball bonding in a bonding machine, and the other end of the bonding wire is bonded to the conductor 8. At this time, the insulating layer 5 does not easily interfere with the movement of the bonding tool of the bonding machine, and the bonding wire is not forcibly pulled downward, so that wire bonding is easy.

更に、本実施形態のように半導体発光素子１１全体が絶縁層５の表面よりも高い位置に配置されている好ましい構成では、半導体発光素子１１からその周囲に放射される光が、絶縁層５に妨げられることなく、逃げ孔６の周辺に差し込み易い。それにより、半導体発光素子１１の周りで光を反射させて光を取出すことができるので、光の取出し効率を高めることができる点で有利である。   Furthermore, in a preferred configuration in which the entire semiconductor light emitting element 11 is disposed at a position higher than the surface of the insulating layer 5 as in the present embodiment, light emitted from the semiconductor light emitting element 11 to the periphery thereof is applied to the insulating layer 5. It is easy to insert into the periphery of the escape hole 6 without being obstructed. Thereby, the light can be extracted by reflecting the light around the semiconductor light emitting element 11, which is advantageous in that the light extraction efficiency can be increased.

金属基板２の長手方向に交互に配置された導体８と半導体発光素子１１とは、ワイヤボンディングにより設けられた金製等のボンディングワイヤ１７で接続されている。更に、前記二列の導体列の他端側に位置した導体８同士は、図１に示すようにワイヤボンディングにより設けられた金製等の端部ボンディングワイヤ１８で接続されている。従って、本実施形態の場合、各半導体発光素子１１は電気的に直列に接続されている。   The conductors 8 and the semiconductor light emitting elements 11 arranged alternately in the longitudinal direction of the metal substrate 2 are connected by bonding wires 17 such as gold provided by wire bonding. Further, the conductors 8 positioned on the other end side of the two conductor rows are connected by an end bonding wire 18 made of gold or the like provided by wire bonding as shown in FIG. Accordingly, in the present embodiment, the semiconductor light emitting elements 11 are electrically connected in series.

以上のように光反射層４が被着された素子取付け部３を有した金属基板２、光反射層１０を有した導体８付きの絶縁層５、半導体発光素子１１、ボンディングワイヤ１７、及び端部ボンディングワイヤ１８によって、照明装置１の面状発光源が形成されている。   As described above, the metal substrate 2 having the element mounting portion 3 to which the light reflecting layer 4 is applied, the insulating layer 5 with the conductor 8 having the light reflecting layer 10, the semiconductor light emitting element 11, the bonding wire 17, and the end. A planar light source of the lighting device 1 is formed by the partial bonding wire 18.

リフレクタ２０は、一個一個又は数個の半導体発光素子１１毎に個別に設けられるものではなく、絶縁層５上の全ての半導体発光素子１１を包囲する単一のものであり、枠、例えば図１に示すように長方形をなす枠で形成されている。リフレクタ２０は絶縁層５に接着されている。電線接続部９の一部は電線を接続するためにリフレクタ２０の外に位置されている。リフレクタ２０の内周面は光反射面となっている。そのために、例えばリフレクタ２０の成形材料である合成樹脂中には酸化アルミニウム等の白色粉末が混入されている。このリフレクタ２０は、光の取出し方向に取出された光を、被照射対象に対して制御をするレンズ等の配光制御部材(図示しない)の取付け部として、利用することが可能である。   The reflector 20 is not individually provided for each one or several semiconductor light emitting elements 11, but is a single one surrounding all the semiconductor light emitting elements 11 on the insulating layer 5. As shown in FIG. 2, it is formed of a rectangular frame. The reflector 20 is bonded to the insulating layer 5. A part of the wire connecting portion 9 is located outside the reflector 20 in order to connect the wire. The inner peripheral surface of the reflector 20 is a light reflecting surface. Therefore, for example, white powder such as aluminum oxide is mixed in the synthetic resin that is a molding material of the reflector 20. The reflector 20 can use the light extracted in the light extraction direction as an attachment portion of a light distribution control member (not shown) such as a lens that controls the irradiation target.

封止部材２２は、リフレクタ２０内に注入して固化されていて、前記面状発光源のリフレクタ２０内に位置された殆どの部分を埋めている。この封止部材２２は、透光性材料例えば透明シリコーン樹脂からなり、その内部には必要により蛍光体が混入されている。本実施形態では半導体発光素子１１が青色発光をするので、この光を吸収して黄色の光を放射する蛍光体(図示しない)が、好ましくは略均一に分散した状態で混入されている。   The sealing member 22 is injected into the reflector 20 and solidified, and fills most of the portion located in the reflector 20 of the planar light source. The sealing member 22 is made of a translucent material such as a transparent silicone resin, and a phosphor is mixed therein if necessary. In the present embodiment, since the semiconductor light emitting element 11 emits blue light, phosphors (not shown) that absorb this light and emit yellow light are preferably mixed in a substantially uniformly dispersed state.

この組み合わせにより、照明装置１の点灯により半導体発光層１３から放出された青色の光の一部が蛍光体に当たることなく封止部材２２を通過する一方で、青色の光が当たった蛍光体が、青色の光で励起されて黄色の光を放射し、この黄色の光が封止部材２２を通過するので、これら補色関係にある二色の混合によって照明装置１の白色光を照射できる。なお、リフレクタ２０が枠形であるので、照明装置１から取出される光の多くは、リフレクタ２０で反射されることなく封止部材２２を透過するので、反射を原因とする光の損失が少なく、光の取出し効率を向上するにも有効である。   By this combination, a part of blue light emitted from the semiconductor light emitting layer 13 by lighting of the lighting device 1 passes through the sealing member 22 without hitting the phosphor, while the phosphor hit by the blue light is The yellow light is excited by the blue light and radiates yellow light, and the yellow light passes through the sealing member 22. Therefore, the white light of the illumination device 1 can be irradiated by mixing these two complementary colors. In addition, since the reflector 20 has a frame shape, most of the light extracted from the lighting device 1 passes through the sealing member 22 without being reflected by the reflector 20, so that the loss of light due to reflection is small. It is also effective in improving the light extraction efficiency.

以上の構成の照明装置１は、各半導体発光素子１１に通電して、これらの半導体発光素子１１の半導体発光層１３を発光させることにより図２中矢印方向に光を取出して照明を行う。   The illuminating device 1 having the above configuration performs illumination by extracting light in the direction of the arrow in FIG. 2 by energizing each semiconductor light emitting element 11 and causing the semiconductor light emitting layer 13 of these semiconductor light emitting elements 11 to emit light.

この照明装置１が備えるダブルワイヤー型の各半導体発光素子１１は全方向に光を放射するが、取分け、半導体発光層１３を基準として表方向つまり金属基板２とは反対側の光の取出し方向に放射される光の強度よりも、裏側つまり金属基板２に向けて放射される光の強度の方が強い。   Each of the double-wire type semiconductor light emitting elements 11 provided in the lighting device 1 emits light in all directions, but in particular, in the surface direction, that is, in the light extraction direction opposite to the metal substrate 2 with respect to the semiconductor light emitting layer 13. The intensity of light emitted toward the back side, that is, the metal substrate 2 is higher than the intensity of emitted light.

そして、裏方向に放射された光の多くは、透光性の素子基板１２及びダイボンド材１６を通って９０％以上の光反射率を有したＡｇメッキ層からなる光反射層４に入射し、この光反射層４で光の取出し方向に反射される。この場合、半導体発光素子１１直下に設けられている光反射層４は、400nm〜740nmの波長の光の全光線反射率に対する拡散反射率の比を80以上とした反射特性を有している、具体的には表１から明らかなように400nm〜740nm区間の平均の比率が98.62であるので、光反射層４での光の反射は、光反射層４で光の取出し方向に正反射（直線反射）される光成分が少なく、光反射層４で光の取出し方向に拡散反射される光成分が多い態様となっている。このように拡散反射される光成分を多くすることは、光反射層４の平均表面粗さ（Ｒａ）を0.25μｍ以上としたことで実現されている。   And most of the light emitted in the back direction is incident on the light reflection layer 4 made of an Ag plating layer having a light reflectance of 90% or more through the light-transmitting element substrate 12 and the die bonding material 16. The light reflecting layer 4 reflects the light in the light extraction direction. In this case, the light reflection layer 4 provided immediately below the semiconductor light emitting element 11 has a reflection characteristic in which the ratio of the diffuse reflectance to the total light reflectance of light having a wavelength of 400 nm to 740 nm is 80 or more. Specifically, as apparent from Table 1, since the average ratio in the 400 nm to 740 nm section is 98.62, the reflection of light at the light reflecting layer 4 is specularly reflected in the light extraction direction at the light reflecting layer 4 (straight line). The light component reflected is small, and the light reflection layer 4 has a large amount of light component diffusely reflected in the light extraction direction. Increasing the light component diffusely reflected in this way is realized by setting the average surface roughness (Ra) of the light reflecting layer 4 to 0.25 μm or more.

これにより、半導体発光素子１１の半導体発光層１３の電極１４，１５の直下に位置した部位からこの部位に対して直角となるように裏側に直進して放出された青色の光の内で、光反射層４で直線反射されることで、その反射方向に位置した電極１４，１５で遮光される光量が減るとともに、光反射層４で拡散反射されることで、電極１４，１５に遮られることなく光の取出し方向に反射される光量が増加する。   As a result, among the blue light emitted from the portion located immediately below the electrodes 14 and 15 of the semiconductor light emitting layer 13 of the semiconductor light emitting element 11 to the back side so as to be perpendicular to this portion, By being linearly reflected by the reflective layer 4, the amount of light blocked by the electrodes 14 and 15 located in the reflection direction is reduced, and by being diffusely reflected by the light reflective layer 4, the light is blocked by the electrodes 14 and 15. The amount of light reflected in the light extraction direction increases.

即ち、電極１４，１５による光の損失が抑制されるので、半導体発光素子１１から放出されて図２中矢印方向に取出される光の取出し効率が向上されるので、被照射対象を照らす明るさを向上できる。ちなみに、本発明者の測定結果によれば、全光線反射率に対する拡散反射率の比を88とした場合の光の取出し効率は100％、同様に、前記の比を99とした場合の光の取出し効率は110％となることが確かめられた。   That is, since the loss of light by the electrodes 14 and 15 is suppressed, the extraction efficiency of light emitted from the semiconductor light emitting element 11 and extracted in the direction of the arrow in FIG. Can be improved. Incidentally, according to the measurement results of the present inventors, the light extraction efficiency when the ratio of the diffuse reflectance to the total light reflectance is 88 is 100%, and similarly, when the ratio is 99, The extraction efficiency was confirmed to be 110%.

加えて、前記裏側方向に放射された光の一部、及び封止部材２２内の蛍光体から放射された光の一部は、白色の絶縁層５に入射し、この絶縁層５で光の取出し方向に反射される。加えて、前記裏側に向かった光の一部は導体８を覆ったＡｇメッキ層からなる光反射層１０に入射し、この光反射層１０で光の取出し方向に反射される。更に、絶縁層５の逃げ孔６の周辺は、その一部が導体８で覆われることがなく、この導体８と逃げ孔６との間おいて露出面５ａを有している。言い換えれば、逃げ孔６の周辺は、その周方向に沿って途切れることなく連続した白色反射面とみなすことができるので、そこに入射した光を、光の取出し方向に反射させることができる。半導体発光素子１１の直下では光反射層４での反射率が下がるほど相対発光強度（取出される光の強さ）が下がり、逆に、反射率が上がるほど相対発光強度が上がる関係があるため、Ａｇメッキ層からなる光反射層１０、及び白色の絶縁層５での高反射特性により、照明装置１の発光効率（光の取出し効率）を向上できる。   In addition, a part of the light emitted in the rear side direction and a part of the light emitted from the phosphor in the sealing member 22 are incident on the white insulating layer 5, and light is transmitted by the insulating layer 5. Reflected in the extraction direction. In addition, part of the light directed toward the back side is incident on the light reflecting layer 10 made of an Ag plating layer covering the conductor 8 and is reflected by the light reflecting layer 10 in the light extraction direction. Furthermore, the periphery of the escape hole 6 of the insulating layer 5 is not partially covered with the conductor 8, and has an exposed surface 5 a between the conductor 8 and the escape hole 6. In other words, since the periphery of the escape hole 6 can be regarded as a continuous white reflecting surface without interruption along the circumferential direction, the light incident thereon can be reflected in the light extraction direction. Immediately below the semiconductor light emitting element 11, the relative light emission intensity (the intensity of the extracted light) decreases as the reflectance at the light reflecting layer 4 decreases, and conversely, the relative light emission intensity increases as the reflectance increases. The luminous efficiency (light extraction efficiency) of the lighting device 1 can be improved by the high reflection characteristics of the light reflection layer 10 made of an Ag plating layer and the white insulating layer 5.

照明装置１の点灯時に各半導体発光素子１１は発熱する。ところで、半導体発光素子１１に電力を導く導体８と金属基板２とは、これらの間に設けた絶縁層５で電気的に絶縁されているが、この絶縁層５は金属基板２と半導体発光素子１１との間には介在されていないとともに、半導体発光素子１１は金属基板２の素子取付け部３にこれ被着された光反射層４を介して直接的にダイボンドされている。   Each semiconductor light emitting element 11 generates heat when the lighting device 1 is turned on. By the way, the conductor 8 for guiding electric power to the semiconductor light emitting element 11 and the metal substrate 2 are electrically insulated by an insulating layer 5 provided therebetween. The insulating layer 5 is electrically insulated from the metal substrate 2 and the semiconductor light emitting element. The semiconductor light emitting element 11 is directly die-bonded to the element mounting portion 3 of the metal substrate 2 via the light reflecting layer 4 attached thereto.

そのため、各半導体発光素子１１が発する熱は、絶縁層５に邪魔されることなく金属基板２に直接的に伝導する。より具体的には、半導体発光素子１１の熱は、実質的に熱抵抗とはならないほど薄いダイボンド材１６を通ってから、Ａｇの光反射層４を経て金属基板２の素子取付け部３に伝えられる。しかも、金属基板２の素子取付け部３は、半導体発光素子１１がダイボンドされた先端面３ａから金属基板２の基板主部２ａに至るに従い次第に太く、言い換えれば、素子取付け部３の断面積が基板主部２ａに近付く程大きくなっているので、半導体発光素子１１から金属基板２の裏面に向けての熱伝導がより容易となる。そして、金属基板２の熱はこの金属基板２の裏面２ｂから外部に放出される。   Therefore, the heat generated by each semiconductor light emitting element 11 is directly conducted to the metal substrate 2 without being disturbed by the insulating layer 5. More specifically, the heat of the semiconductor light-emitting element 11 passes through the die-bonding material 16 that is so thin that it does not substantially become thermal resistance, and then is transmitted to the element mounting portion 3 of the metal substrate 2 through the Ag light reflecting layer 4. It is done. Moreover, the element mounting portion 3 of the metal substrate 2 gradually becomes thicker from the tip surface 3a to which the semiconductor light emitting element 11 is die-bonded to the substrate main portion 2a of the metal substrate 2, in other words, the cross-sectional area of the element mounting portion 3 is the substrate. Since it becomes so large that it approaches the main part 2a, the heat conduction from the semiconductor light emitting element 11 toward the back surface of the metal substrate 2 becomes easier. The heat of the metal substrate 2 is released from the back surface 2b of the metal substrate 2 to the outside.

こうして半導体発光素子１１の熱が高効率に金属基板２を通って外部に放出されるので、各半導体発光素子１１の温度上昇が効果的に抑制され、各半導体発光素子１１の温度を設計通りに維持できる。そのため、各半導体発光素子１１の発光効率の低下と、各半導体発光素子１１が発する光量のばらつきが抑制され、その結果的として、各半導体発光素子１１から取出される光の色むらを抑制できる。   In this way, the heat of the semiconductor light emitting element 11 is released to the outside through the metal substrate 2 with high efficiency, so that the temperature rise of each semiconductor light emitting element 11 is effectively suppressed, and the temperature of each semiconductor light emitting element 11 is set as designed. Can be maintained. Therefore, a decrease in the light emission efficiency of each semiconductor light emitting element 11 and a variation in the amount of light emitted from each semiconductor light emitting element 11 are suppressed, and as a result, uneven color of light extracted from each semiconductor light emitting element 11 can be suppressed.

したがって、前記構成の照明装置１は、高熱伝導により各半導体発光素子１１の温度上昇による発光効率の低下を抑制しつつ、各半導体発光素子１１の裏側に放射された光の高反射特性により、光の取出し効率を向上できる。   Therefore, the illumination device 1 having the above-described configuration suppresses a decrease in light emission efficiency due to a temperature rise of each semiconductor light emitting element 11 due to high heat conduction, and has a high reflection characteristic of light emitted to the back side of each semiconductor light emitting element 11. The extraction efficiency can be improved.

又、金属基板２の素子取付け部３に半導体発光素子１１をダイボンドしたダイボンド材１６を形成した透明なシリコーン樹脂は、熱等を受けても変色を伴って劣化する可能性が極めて小さい。したがって、半導体発光素子１１の直下の光反射層４で反射されて取出される光の取出し効率を長期にわたり維持できる。   In addition, the transparent silicone resin in which the die bonding material 16 in which the semiconductor light emitting element 11 is die-bonded to the element mounting portion 3 of the metal substrate 2 is very unlikely to deteriorate with discoloration even when receiving heat or the like. Accordingly, it is possible to maintain the extraction efficiency of light reflected and extracted by the light reflection layer 4 directly below the semiconductor light emitting element 11 for a long period of time.

本発明は前記一実施形態には制約されない。例えば、半導体発光層１３が青色の光を発光するものに限定した照明装置１の場合、光反射層４の反射特性を、460nmの波長の青色光の反射率に対する拡散反射率の比が80以上好ましくは90以上となる設定にして実施することができる。なお、その他の構成は前記一実施形態と同じである。したがって、こうした照明装置１においても、前記一実施形態で説明した理由により本発明の課題を解決できる。   The present invention is not limited to the one embodiment. For example, in the case of the lighting device 1 limited to the semiconductor light emitting layer 13 that emits blue light, the reflection characteristic of the light reflecting layer 4 is set such that the ratio of diffuse reflectance to blue light with a wavelength of 460 nm is 80 or more. Preferably, the setting can be 90 or more. The rest of the configuration is the same as in the above embodiment. Therefore, also in such an illuminating device 1, the subject of this invention can be solved for the reason demonstrated in the said one Embodiment.

１…照明装置、２…金属基板、２ａ…基板主部、３…素子取付け部、３ａ…素子取付け部の先端面、４…光反射層、５…絶縁層、６…逃げ孔、７…接着剤、８…導体、１１…半導体発光素子、１２…素子基板、１３…半導体発光層、１４，１５…電極、１６…ダイボンド材、１７…ボンディングワイヤ、２２…封止部材 DESCRIPTION OF SYMBOLS 1 ... Illuminating device, 2 ... Metal substrate, 2a ... Substrate main part, 3 ... Element attachment part, 3a ... Tip surface of element attachment part, 4 ... Light reflection layer, 5 ... Insulating layer, 6 ... Escape hole, 7 ... Adhesion Agent, 8 ... Conductor, 11 ... Semiconductor light emitting element, 12 ... Element substrate, 13 ... Semiconductor light emitting layer, 14, 15 ... Electrode, 16 ... Die bond material, 17 ... Bonding wire, 22 ... Sealing member

Claims (1)

素子取付け部を一体に有する金属基板と；
金属基板に前記素子取付け部を除いて積層された絶縁層と；
この絶縁層上に設けられた導体と；
透光性の素子基板の一面であって前記導体の表面より高い位置く位置される半導体発光層を有するとともにこの発光層上に電極が設けられた前記素子取付け部に設けられる半導体発光素子と；
前記素子取付け部及び前記導体に積層されるとともに前記金属基板をなした金属の反射率よりも高い反射率を有した銀製の光反射層であって、平均表面粗さ0.25μmであって、400nm〜740nmの波長の光の全光線反射率に対する拡散反射率の比を80以上とした前記光反射層と；
前記素子基板の他面を前記光反射層に接着して前記半導体発光素子を前記素子取付け部にダイボンドした透光性のダイボンド材と；
前記半導体発光素子の電極と前記導体とを接続したボンディングワイヤと；
前記半導体発光素子を封止して設けた蛍光体が混入された透光性の封止部材と；
を具備したことを特徴とする照明装置。 A metal substrate integrally having an element mounting portion;
An insulating layer laminated on the metal substrate excluding the element mounting portion;
A conductor provided on the insulating layer;
A semiconductor light-emitting element provided on the element mounting portion having a semiconductor light-emitting layer located on one surface of the light-transmitting element substrate and positioned higher than the surface of the conductor; and an electrode provided on the light-emitting layer;
A light reflecting layer made of silver having a reflectance higher than that of the metal layered on the element mounting portion and the conductor and forming the metal substrate, and having an average surface roughness of 0.25 μm and 400 nm The light reflecting layer having a ratio of diffuse reflectance to total light reflectance of light having a wavelength of ˜740 nm of 80 or more;
A translucent die-bonding material in which the other surface of the element substrate is bonded to the light reflecting layer and the semiconductor light emitting element is die-bonded to the element mounting portion;
A bonding wire connecting the electrode of the semiconductor light emitting element and the conductor;
A translucent sealing member mixed with a phosphor provided by sealing the semiconductor light emitting element;
An illumination device comprising:
JP2010178496A 2007-05-31 2010-08-09 Lighting device Pending JP2010263242A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2010178496A JP2010263242A (en) 2007-05-31 2010-08-09 Lighting device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2007145334 2007-05-31
JP2010178496A JP2010263242A (en) 2007-05-31 2010-08-09 Lighting device

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
JP2008138226A Division JP4771179B2 (en) 2007-05-31 2008-05-27 Lighting device

Publications (1)

Publication Number Publication Date
JP2010263242A true JP2010263242A (en) 2010-11-18

Family

ID=40325090

Family Applications (2)

Application Number Title Priority Date Filing Date
JP2008138226A Expired - Fee Related JP4771179B2 (en) 2007-05-31 2008-05-27 Lighting device
JP2010178496A Pending JP2010263242A (en) 2007-05-31 2010-08-09 Lighting device

Family Applications Before (1)

Application Number Title Priority Date Filing Date
JP2008138226A Expired - Fee Related JP4771179B2 (en) 2007-05-31 2008-05-27 Lighting device

Country Status (1)

Country Link
JP (2) JP4771179B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016025160A (en) * 2014-07-17 2016-02-08 シチズン電子株式会社 Led light emitting device and manufacturing method of the same
JP2018200332A (en) * 2017-05-25 2018-12-20 オリンパス株式会社 Illuminator for microscope, and microscope

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010192606A (en) * 2009-02-17 2010-09-02 Toshiba Lighting & Technology Corp Light-emitting device
JP2010225607A (en) * 2009-03-19 2010-10-07 Toshiba Lighting & Technology Corp Light emitting device
JP2010251686A (en) 2009-03-26 2010-11-04 Harison Toshiba Lighting Corp Light emitting device and method for manufacturing the same
JP5330889B2 (en) * 2009-04-14 2013-10-30 電気化学工業株式会社 LED module for lighting
JP5479214B2 (en) * 2009-05-28 2014-04-23 電気化学工業株式会社 Manufacturing method of light emitting element mounting substrate
JP2011014890A (en) 2009-06-02 2011-01-20 Mitsubishi Chemicals Corp Metal substrate and light source device
JP5275140B2 (en) * 2009-06-04 2013-08-28 昭和電工株式会社 Lighting device and light emitting device
CN102804429A (en) * 2009-06-24 2012-11-28 古河电气工业株式会社 Lead frame for optical semiconductor device, process for manufacturing lead frame for optical semiconductor device, and optical semiconductor device
JP5746620B2 (en) 2009-06-26 2015-07-08 株式会社朝日ラバー White reflector and manufacturing method thereof
EP2551929A4 (en) 2010-03-23 2013-08-14 Asahi Rubber Inc Silicone resin reflective substrate, manufacturing method for same, and base material composition used in reflective substrate
KR101847938B1 (en) * 2011-03-14 2018-04-13 삼성전자주식회사 Light emitting device package and manufacturing method thereof
KR101533068B1 (en) * 2014-02-28 2015-07-01 아이지티 주식회사 PCB and Semiconductor module including the same
JP6846866B2 (en) * 2015-12-24 2021-03-24 株式会社シンテック Reflector for LED light emitting element
CN110731129B (en) * 2017-06-09 2024-01-09 电化株式会社 Ceramic circuit board

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1126811A (en) * 1997-07-02 1999-01-29 Toshiba Corp Semiconductor light emitting device
JP2005136224A (en) * 2003-10-30 2005-05-26 Asahi Kasei Electronics Co Ltd Light-emitting diode illumination module
JP2005209958A (en) * 2004-01-23 2005-08-04 Kyocera Corp Light emitting storage package and light emitting device
JP2008199000A (en) * 2007-01-18 2008-08-28 Citizen Electronics Co Ltd Semiconductor light-emitting device

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3065258B2 (en) * 1996-09-30 2000-07-17 日亜化学工業株式会社 Light emitting device and display device using the same
JP3028813B1 (en) * 1999-06-23 2000-04-04 サンケン電気株式会社 Semiconductor light emitting device
JP4432275B2 (en) * 2000-07-13 2010-03-17 パナソニック電工株式会社 Light source device
JP2002049326A (en) * 2000-08-02 2002-02-15 Fuji Photo Film Co Ltd Plane light source and display element using the same
JP4045781B2 (en) * 2001-08-28 2008-02-13 松下電工株式会社 Light emitting device
WO2003030274A1 (en) * 2001-09-27 2003-04-10 Nichia Corporation Light-emitting device and its manufacturing method
JP2004095941A (en) * 2002-09-02 2004-03-25 Toyoda Gosei Co Ltd Light emitting device
JP2004319939A (en) * 2003-02-25 2004-11-11 Kyocera Corp Package for housing light emitting element and light emitting device
JP4862274B2 (en) * 2005-04-20 2012-01-25 パナソニック電工株式会社 Method for manufacturing light emitting device and method for manufacturing light emitting device unit using the light emitting device
JP2007067116A (en) * 2005-08-30 2007-03-15 Toshiba Lighting & Technology Corp Light-emitting device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1126811A (en) * 1997-07-02 1999-01-29 Toshiba Corp Semiconductor light emitting device
JP2005136224A (en) * 2003-10-30 2005-05-26 Asahi Kasei Electronics Co Ltd Light-emitting diode illumination module
JP2005209958A (en) * 2004-01-23 2005-08-04 Kyocera Corp Light emitting storage package and light emitting device
JP2008199000A (en) * 2007-01-18 2008-08-28 Citizen Electronics Co Ltd Semiconductor light-emitting device

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2016025160A (en) * 2014-07-17 2016-02-08 シチズン電子株式会社 Led light emitting device and manufacturing method of the same
US10084122B2 (en) 2014-07-17 2018-09-25 Citizen Electronics Co., Ltd. Light-emitting apparatus and method of manufacturing the same
JP2018200332A (en) * 2017-05-25 2018-12-20 オリンパス株式会社 Illuminator for microscope, and microscope

Also Published As

Publication number Publication date
JP2009010360A (en) 2009-01-15
JP4771179B2 (en) 2011-09-14

Similar Documents

Publication Publication Date Title
JP4771179B2 (en) Lighting device
JP5273486B2 (en) Lighting device
JP4674282B2 (en) LED module for line light source
KR100752586B1 (en) Light-emitting apparatus and illuminating apparatus
JP4678391B2 (en) Lighting equipment
TWI581450B (en) Semiconductor light emitting module and manufacturing method thereof
JP4600455B2 (en) Lighting device
JP3872490B2 (en) Light emitting element storage package, light emitting device, and lighting device
KR20080042921A (en) Light-emitting device
JP2006049814A (en) Light emitting device and illumination system
JP2008244165A (en) Lighting system
JP4948818B2 (en) Light emitting device and lighting device
JP2009289810A (en) Illuminator
JP4948841B2 (en) Light emitting device and lighting device
JP2008078401A (en) Lighting device
JP2015050303A (en) Light-emitting device
JP2005210042A (en) Light emitting apparatus and illumination apparatus
JP2008251664A (en) Illumination apparatus
JP5125060B2 (en) Light emitting device
JP5817297B2 (en) Light emitting device and lighting device
JP2009231397A (en) Lighting system
JP2006066657A (en) Light emitting device and lighting device
JP2007266222A (en) Substrate for loading light emitting element, package for storing light emitting element, light emitting device and light system
JP2006237571A (en) Light-emitting diode device
JP2008235720A (en) Illumination apparatus

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20100831

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20121114

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20121122

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20130314