JP2009088116A

JP2009088116A - Luminaire

Info

Publication number: JP2009088116A
Application number: JP2007253849A
Authority: JP
Inventors: Tomohiro Sanpei; 友広三瓶; Masahiro Izumi; 昌裕泉; Kiyoshi Otani; 清大谷; Kiyoshi Yokokura; 清横倉; Shinji Nogi; 新治野木
Original assignee: Toshiba Lighting and Technology Corp
Current assignee: Toshiba Lighting and Technology Corp
Priority date: 2007-09-28
Filing date: 2007-09-28
Publication date: 2009-04-23

Abstract

<P>PROBLEM TO BE SOLVED: To improve light extraction efficiency while suppressing an increase in the temperature of a semiconductor light-emitting device. <P>SOLUTION: The luminaire comprises: a copper substrate 2 which has one surface and also has a device fitting portion formed of a projection portion on the one surface in one body, the device fitting portion being formed gradually thicker from a tip surface thereof to the one surface; a nickel layer 30 formed on the tip surface of the device fitting portion and a tapered circumferential surface reaching the one surface continuously from the tip surface; a silver layer 4 formed on the nickel layer; an insulating layer 5 having a through hole into which the device fitting portion is inserted and bonded to the copper substrate with an adhesion substrate; a copper pattern 8 formed on the copper pattern 8; a silver layer 10 formed on the nickel layer; the semiconductor light emitting device 11 die-bonded to the silver layer; a bonding wire 17 connecting the semiconductor light emitting device and a conductor to each other; and a transparent sealing member 22 with which a phosphor is mixed and in which the device fitting portion, semiconductor light emitting element, and a bonding wire are embedded. <P>COPYRIGHT: (C)2009,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、光源がＬＥＤチップである照明装置で、金属ベースプリント基板の金属ベース板に形成した突台部にＬＥＤチップをダイボンドして、ＬＥＤチップが発した熱を外部に効率よく放出する技術が知られている（特許文献１等参照。）。 2. Description of the Related Art Conventionally, there is known a technology for efficiently radiating heat generated by an LED chip to the outside by die-bonding the LED chip to a protruding part formed on a metal base plate of a metal base printed board in an illumination device whose light source is an LED chip. (See Patent Document 1, etc.).

詳しくは、アルミニウム等の金属ベース板の一面に突台部を形成するとともに、前記一面に突台部が挿入される孔を有した絶縁部材を接着層により積層し、ダイボンド材を用いて前記突台部の先端面にＬＥＤチップを熱的に結合させて配置している。絶縁部材は前記孔とこれに挿入された突台部を囲む張出部を有している。そして、突台部及びＬＥＤチップを中央部に配した丸孔を有する絶縁部材に配線パターンを設け、このパターンの張出部に位置する部位とＬＥＤチップをボンディングワイヤにより電気的に接続するとともに、蛍光体が分散された透光性封止樹脂を前記丸孔に充填して、配線パターンとＬＥＤチップとボンディングワイヤを封止している。
特開２００２−９４１２２号公報（段落００１０−００１６、００５２−０１４１、図１−図２３） Specifically, a projecting portion is formed on one surface of a metal base plate such as aluminum, and an insulating member having a hole into which the projecting portion is inserted is stacked on an adhesive layer, and the projecting portion is formed using a die bond material. An LED chip is thermally coupled to the tip surface of the base part. The insulating member has an overhang portion that surrounds the hole and the protruding portion inserted into the hole. Then, a wiring pattern is provided in the insulating member having a round hole in which the protruding portion and the LED chip are arranged in the center portion, and the portion located in the projecting portion of the pattern and the LED chip are electrically connected by a bonding wire, The round hole is filled with a translucent sealing resin in which a phosphor is dispersed to seal the wiring pattern, the LED chip, and the bonding wire.
JP 2002-94122 A (paragraphs 0010-0016, 0052-0141, FIG. 1 to FIG. 23)

特許文献１の光源装置では、ＬＥＤチップの熱をこれに熱的に結合された突台部を有した金属ベース板に直接的に放出して、ＬＥＤチップの温度上昇を抑制できる。しかし、この光源装置は、ＬＥＤチップから放出される光の取出しが十分ではない。 In the light source device of Patent Document 1, the heat of the LED chip can be directly emitted to the metal base plate having the protruding portion thermally coupled thereto, and the temperature rise of the LED chip can be suppressed. However, this light source device does not sufficiently extract light emitted from the LED chip.

具体的には、ＬＥＤチップから放出された光の一部が、封止樹脂中の蛍光体に吸収されて他の色の光に変換されて放射されるに伴い、突台部側に向かった放射光の一部が突台部で反射されて光源装置の光の出射方向に取出される。この取出しにおいて、特許文献１の光源装置では、突台部に入射した光を効率よく反射させる工夫がないので、突台部をなすＡｌやＣｕ等の金属の地肌面でそこに入射した光が吸収され易い。しかも、突台部はその周囲を絶縁部材の張出部で覆われているので、突台部の先端面の内でＬＥＤチップの周囲に露出した限られた面積でしか、蛍光体から放射された光を反射することができない。 Specifically, part of the light emitted from the LED chip was absorbed by the phosphor in the sealing resin, converted into light of another color, and then emitted toward the bumper side. A part of the radiated light is reflected by the protrusion and taken out in the light emitting direction of the light source device. In this extraction, the light source device of Patent Document 1 does not have a device for efficiently reflecting the light incident on the projecting portion. Therefore, the light incident on the ground surface of a metal such as Al or Cu forming the projecting portion is not provided. Easy to be absorbed. Moreover, since the periphery of the projecting portion is covered with the protruding portion of the insulating member, the phosphor is radiated from the phosphor only in a limited area exposed around the LED chip within the tip surface of the projecting portion. Cannot reflect the light.

本発明の目的は、半導体発光素子の温度上昇を抑制しつつ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。 The objective of this invention is providing the illuminating device which can improve the extraction efficiency of light, suppressing the temperature rise of a semiconductor light-emitting device.

請求項１に記載の発明は、一面を有しこの一面に凸部からなる素子取付け部が一体に形成された銅基板であって、前記素子取付け部がその先端面から前記一面に至るに従い次第に太く形成された銅基板と；前記素子取付け部の先端面及びこれに連続して前記一面に至るテーパ状周面に形成されたニッケル層と；ニッケル層の上に形成された銀層と；前記素子取付け部が挿入される通孔を有して前記銅基板の一面に接着層により接着して積層された絶縁層と；この絶縁層上に設けられた銅パターンと；この銅パターン上に形成されたニッケル層と；ニッケル層の上に形成された銀層と；前記素子取付け部の先端面を覆った銀層にダイボンドされた半導体発光素子と；この半導体発光素子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から放出された光の一部により励起され異なる色の光を放射する蛍光体が混入されていて、前記素子取付け部、半導体発光素子、及びボンディングワイヤを埋設した透光性封止部材と；を具備したことを特徴とする。 The invention according to claim 1 is a copper substrate having one surface and an element mounting portion formed of a convex portion integrally formed on the one surface, and the element mounting portion gradually increases from the tip surface to the one surface. A thick copper substrate; a nickel layer formed on a tip end surface of the element mounting portion and a tapered peripheral surface extending continuously to the one surface; a silver layer formed on the nickel layer; An insulating layer having a through-hole into which an element mounting portion is inserted and bonded and laminated on one surface of the copper substrate with an adhesive layer; a copper pattern provided on the insulating layer; and formed on the copper pattern A nickel layer formed thereon; a silver layer formed on the nickel layer; a semiconductor light emitting element die-bonded to the silver layer covering the tip surface of the element mounting portion; and connecting the semiconductor light emitting element and the conductor Bonding wire; said semiconductor A translucent sealing member in which a phosphor that is excited by a part of the light emitted from the light emitting element and emits light of different colors is mixed, and the element mounting portion, the semiconductor light emitting element, and the bonding wire are embedded; It is characterized by comprising;

請求項１の発明で、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。又、銅パターンは、エッチング処理により好適に設けることができるが、接着剤を用いて絶縁層上に貼付けられたものであってもよい。すなわち、銅パターンは、銅であればその形態等は問わない。この銅パターン上にニッケル層が形成され、さらに、ニッケル層の上に銀層が形成され、ニッケル及び銀はメッキにより形成されていてもよい。そして、ニッケル層は銅の耐マイグレーション性の向上と、酸化等を抑制できる点で好ましい。すなわち、マイグレーションにより銅は、ニッケル層に侵入するが銀層までには至らないため、銀の反射率が低下するのを抑制することができる。 In the invention of claim 1, 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 Moreover, although a copper pattern can be suitably provided by an etching process, what was affixed on the insulating layer using the adhesive agent may be used. That is, the form of the copper pattern is not limited as long as it is copper. A nickel layer may be formed on the copper pattern, a silver layer may be formed on the nickel layer, and nickel and silver may be formed by plating. And a nickel layer is preferable at the point which can improve the migration resistance of copper, and can suppress oxidation etc. That is, copper penetrates the nickel layer by migration, but does not reach the silver layer, so that the reflectance of silver can be suppressed from decreasing.

また、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が、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。また、素子取付け部に半導体発光素子をダイボンドするには、ダイボンド材（接着剤）を用いるが、このダイボンド材の厚みは接着機能を失わない範囲で１０μｍ以下にするとよく、又、光の取出し性能をより向上させる上では、ダイボンド材を透光性として、半導体発光素子から放射された光の一部を素子取付け部で反射させることが好ましい。更に、ダイボンド材には、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。ダイボンド材を透明シリコーン樹脂とすることは、ダイボンド材が変色を伴って劣化する可能性が極めて小さいので、長期にわたり光の取出し効率を維持できる点で好ましい。 Further, 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. However, at least two of the blue LED chip, the red LED chip, and the green LED chip can be used. It is also possible to use various types of LED chips in combination. A die-bonding material (adhesive) is used to die-bond the semiconductor light-emitting element to the element mounting portion. The thickness of the die-bonding material may be 10 μm or less as long as the bonding function is not lost, and the light extraction performance. In order to further improve the above, it is preferable to make the die bond material translucent and reflect a part of the light emitted from the semiconductor light emitting element at the element mounting portion. Further, frit glass or translucent synthetic resin such as transparent silicone resin can be used as the die bond material. It is preferable to use a transparent silicone resin as the die bond material because the possibility that the die bond material is deteriorated with discoloration is extremely small, and the light extraction efficiency can be maintained over a long period of time.

さらに、半導体発光素子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、熱硬化性の透光性合成樹脂、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、例えば発光源である半導体発光素子に青色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、青色の光を吸収し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、或いは紫外光を吸収して赤色の光を放射する蛍光体、紫外光を吸収して緑色の光を放射する蛍光体、及び紫外光を吸収し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。 Further, the light-transmitting sealing member that shields the semiconductor light-emitting element from the outside air and moisture and prevents the lifetime of the element from being reduced includes a thermosetting light-transmitting synthetic resin such as an epoxy resin, a silicone resin, a urethane resin, and the like. In addition, transparent low melting point glass can also be used. For example, in the case of a lighting device that emits white light using a blue LED chip as a semiconductor light-emitting element that is a light-emitting source, sealing in which a phosphor that absorbs blue light and emits yellow light is mixed. A phosphor that absorbs ultraviolet light and emits red light, a phosphor that absorbs ultraviolet light and emits green light, and a phosphor that absorbs ultraviolet light and emits yellow light may be used. What is necessary is just to use the sealing member with which each fluorescent substance was mixed.

前記銅パターン及びボンディングワイヤを介して半導体発光素子に通電することにより、この素子を発光させ、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。この点灯時に、銅パターンと銅基板との間の電気的絶縁を担う絶縁層は、銅基板と半導体発光素子との間には介在されておらず、又、半導体発光素子は銅基板と一体の素子取付け部に直接的に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銀層、ニッケル層及びダイボンド材を経て銅基板の素子取付け部に直接的に伝導する。しかも、素子取付け部の断面積は絶縁層が接着された銅基板の一面に近付く程大きいので、半導体発光素子から銅基板の背面に向けての熱伝導がより容易となる。従って、半導体発光素子の熱が、高効率で銅基板に伝わってこの銅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。 By energizing the semiconductor light emitting element through the copper pattern and the bonding wire, this element emits light, the light is transmitted through the sealing member and taken out to the outside, and illumination in the taking direction is performed. During this lighting, the insulating layer responsible for electrical insulation between the copper pattern and the copper substrate is not interposed between the copper substrate and the semiconductor light emitting element, and the semiconductor light emitting element is integrated with the copper substrate. It is die-bonded directly to the element mounting portion. Therefore, the heat generated by the semiconductor light emitting element during lighting is directly conducted to the element mounting portion of the copper substrate through the silver layer, the nickel layer, and the die bond material without being interrupted by the insulating layer. In addition, since the cross-sectional area of the element mounting portion increases as it approaches one surface of the copper substrate to which the insulating layer is bonded, heat conduction from the semiconductor light emitting element toward the back surface of the copper substrate becomes easier. Therefore, since the heat of the semiconductor light emitting element is transmitted to the copper substrate with high efficiency and is released to the outside, the temperature rise of the semiconductor light emitting element can be effectively suppressed.

この照明装置の点灯時に、封止部材中の蛍光体から放射された光の一部は、素子取付け部に入射される。この場合、素子取付け部の先端面の内でＬＥＤチップの周囲だけではなく、この先端面に連なっているテーパ状周面にも前記放射光の一部が入射可能であるから、反射面積を大きく確保できる。その上、素子取付け部の先端面及びテーパ状周面には銀層が形成されており、この銀層の光反射率は９０％以上と高い。そのため、ＬＥＤチップの放熱を促進させる素子取付け部を利用して、照明装置の光の出射方向に取出される光の取出し効率を向上させることができる。 When the lighting device is turned on, a part of the light emitted from the phosphor in the sealing member is incident on the element mounting portion. In this case, a part of the radiated light can be incident not only on the LED chip around the tip surface of the element mounting portion but also on the tapered peripheral surface connected to the tip surface. It can be secured. In addition, a silver layer is formed on the tip surface and the tapered peripheral surface of the element mounting portion, and the light reflectance of this silver layer is as high as 90% or more. Therefore, the extraction efficiency of the light extracted in the light emission direction of the lighting device can be improved by using the element mounting portion that promotes the heat dissipation of the LED chip.

請求項２の発明は、前記接着層が前記素子取付け部の根元方向への食み出し部を有し、前記通孔の内面に対する前記の食み出し部の食み出し寸法を0.2mm以下とするとともに、前記テーパ状周面に形成された銀層を前記食み出し部に連続させたことを特徴としている。 In the invention of claim 2, the adhesive layer has a protruding portion in the root direction of the element mounting portion, and the protruding size of the protruding portion with respect to the inner surface of the through hole is 0.2 mm or less. In addition, a silver layer formed on the tapered peripheral surface is continuous with the protruding portion.

この発明では、接着層が素子取付け部の根元方向への食み出し部を有しているから、封止部材を設ける前の状態で、接着層が絶縁層の通孔の内面に対して素子取付け部から遠ざかるように引っ込んでいる場合のように、絶縁層と銅基板との間に通孔に連通する空気溜りが形成されることがない。そのため、熱硬化性の樹脂からなる封止部材を加熱硬化して封止する際、又は低融点ガラスで封止する際に、前記空気溜り内の空気が未硬化の封止部材内に流出して気泡となって残留しないようにできる。そして、絶縁層の通孔の内面に対する前記食み出し部を、テーパ状周面に形成された銀層に連続させるとともに、その食み出し寸法を0.2mm以下としたので、銀層の面積が減ることは実質的に無視できるとともに、接着層が着色されている場合、その食み出し部による光の吸収も実質的に無視できるので、光の取出し効率を向上させる上で前記食み出し部が実質的な支障とならないようにできる。 In this invention, since the adhesive layer has a protruding portion in the root direction of the element mounting portion, the adhesive layer is in contact with the inner surface of the through hole of the insulating layer before the sealing member is provided. There is no formation of an air pocket communicating with the through hole between the insulating layer and the copper substrate, as in the case of retracting away from the mounting portion. Therefore, when the sealing member made of a thermosetting resin is heat-cured and sealed, or when sealed with low-melting glass, the air in the air reservoir flows into the uncured sealing member. Can be prevented from remaining as bubbles. And since the said protrusion part with respect to the inner surface of the through-hole of an insulating layer was continued with the silver layer formed in the taper-shaped surrounding surface, and the protrusion dimension was 0.2 mm or less, the area of a silver layer is The reduction can be substantially ignored, and when the adhesive layer is colored, the absorption of light by the protruding portion can be substantially ignored, so that the protruding portion is improved in improving the light extraction efficiency. Can be prevented from substantial trouble.

請求項１の発明の照明装置によれば、半導体発光素子の温度上昇を抑制しつつ素子取付け部での反射を良好として光の取出し効率を向上できる。 According to the illumination device of the first aspect of the present invention, it is possible to improve the light extraction efficiency by improving the reflection at the element mounting portion while suppressing the temperature rise of the semiconductor light emitting element.

請求項２の発明の照明装置によれば、封止部材で半導体発光素子を封止することに伴い封止部材内に気泡が残留しないようにできるとともに、これを実現するための絶縁層の食み出し部が、照明装置の光の出射方向に取出される光の取出し効率を向上させる上で実質的な支障とならないようにできる。 According to the illumination device of the second aspect of the present invention, it is possible to prevent bubbles from remaining in the sealing member as the semiconductor light emitting element is sealed with the sealing member, and to prevent the corrosion of the insulating layer for realizing this. It is possible to prevent the protruding portion from substantially hindering the efficiency of extracting the light extracted in the light emitting direction of the lighting device.

図１〜図３を参照して本発明の第１実施形態を説明する。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銅基板２と、銀層４としての銀メッキ層、ニッケル層３０としてのニッケルメッキ層と、絶縁層５と、複数の銅パターン８と、複数の半導体発光素子例えばＬＥＤチップ１１と、ボンディングワイヤ１７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。 A first embodiment of the present invention will be described with reference to FIGS. Reference numeral 1 in FIG. 1 denotes an illumination device that forms an LED package. The lighting device 1 includes a package substrate, for example, a copper substrate 2, a silver plating layer as the silver layer 4, a nickel plating layer as the nickel layer 30, an insulating layer 5, a plurality of copper patterns 8, and a plurality of semiconductor light emitting elements. For example, the LED chip 11, the bonding wire 17, the reflector 20, and the sealing member 22 are formed.

銅基板２は、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長方形状をなしている。図２に示す銅基板２の一面(正面)２ｂに、この銅基板２と一体の凸部からなる素子取付け部３が例えばＬＥＤチップ１１と同数形成されている。素子取付け部３を除いた基板主部２ａ（図２参照）の厚みは例えば０．１８μｍである。素子取付け部３が設けられていない銅基板２の他面（背面）２ｃは、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 copper substrate 2 has a predetermined shape, for example, a rectangular shape, in order to obtain a light emitting area required for the lighting device 1. On the one surface (front surface) 2 b of the copper substrate 2 shown in FIG. 2, the same number of element mounting portions 3 as convex portions integrated with the copper substrate 2 are formed, for example. The thickness of the substrate main portion 2a (see FIG. 2) excluding the element attachment portion 3 is, for example, 0.18 μm. The other surface (back surface) 2c of the copper substrate 2 on which the element mounting portion 3 is not provided is used as a heat transfer surface that is in surface contact with the heat dissipation surface or another heat dissipation member.

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２ｂ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から銅基板２の一面２ｂ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から銅基板２の一面２ｂ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。そのため、素子取付け部３はその先端面３ａから銅基板２の一面にわたるテーパ状周面３ｂを有している。このテーパ状周面３ｂと銅基板２の一面２ｂとはこれらの間に角を作ることなく弧状をなして連続している。先端面３ａの直径は例えば０．５７ｍｍであり、素子取付け部３の最大径をなす根元の直径は例えば１．０８ｍｍである。 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 2b. The element mounting portion 3 is gradually formed thicker from the tip end surface 3a to the one surface 2b of the copper 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 the one surface 2 b of the copper substrate 2. For this reason, the element mounting portion 3 has a tapered peripheral surface 3 b extending from the tip surface 3 a to one surface of the copper substrate 2. The tapered peripheral surface 3b and the one surface 2b of the copper substrate 2 are continuous in an arc without forming a corner therebetween. The diameter of the distal end surface 3a is, for example, 0.57 mm, and the diameter of the root that forms the maximum diameter of the element mounting portion 3 is, for example, 1.08 mm.

表面素子取付け部３の略全体にニッケルメッキ層を介して銀メッキ層４が形成されている。ニッケルメッキ層は、銅基板２の銅がマイグレーションにより銀メッキ層に侵入するのを抑制し、銀の反射率が低下するのを抑制している。また、銀メッキ層４は、表面素子取付け部３の先端面３ａ全体に形成された端面メッキ部４ａと、これに一体に連続した表面素子取付け部３のテーパ状周面３ｂの略全体に形成された周面数メッキ部４ｂとからなる。銀メッキ層４は無電解メッキにより設けられた薄膜であって、その膜厚は例えば０．３μｍ〜０．４μｍである。この銀メッキ層４の光の反射率は９０％以上である。ニッケルメッキ層が銅のマイグレーションを抑制するので上記反射率を長期間維持することができ、発光効率が低下しにくくなる。銀メッキ層４ａを含めた素子取付け部３の高さは、図２においてＬＥＤチップ１１の上面の高さ位置を銅パターン８の高さ位置以上とすることが好ましい。 A silver plating layer 4 is formed on substantially the entire surface element mounting portion 3 via a nickel plating layer. The nickel plating layer suppresses the copper of the copper substrate 2 from entering the silver plating layer due to migration, and suppresses the silver reflectance from decreasing. Further, the silver plating layer 4 is formed on substantially the entire end surface plating portion 4a formed on the entire front end surface 3a of the surface element attachment portion 3 and the tapered peripheral surface 3b of the surface element attachment portion 3 continuous integrally therewith. The peripheral surface number plated portion 4b. The silver plating layer 4 is a thin film provided by electroless plating, and the film thickness is, for example, 0.3 μm to 0.4 μm. The light reflectance of the silver plating layer 4 is 90% or more. Since the nickel plating layer suppresses copper migration, the reflectance can be maintained for a long time, and the light emission efficiency is unlikely to decrease. The height of the element mounting portion 3 including the silver plating layer 4a is preferably set so that the height position of the upper surface of the LED chip 11 is equal to or higher than the height position of the copper pattern 8 in FIG.

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。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、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。絶縁層５は素子取付け部３が個々に挿入される複数の通孔６を有している。通孔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以上に大きい。本実施形態では素子取付け部３の根元部の直径と同径の１．０８ｍｍとしてある。 For example, a white glass epoxy substrate is used for the insulating layer 5 in order to obtain light reflection performance. In this embodiment, the insulating layer 5 is formed as a single layer, but it can also be formed as two layers, thereby ensuring a higher withstand voltage than that of a single layer. The insulating layer 5 has a plurality of through holes 6 into which the element mounting portions 3 are individually inserted. The through-hole 6 is circular, for example, and its diameter is larger than the diameter of the root portion that forms the maximum diameter of the element mounting portion 3. In this embodiment, the diameter is 1.08 mm which is the same diameter as the diameter of the base portion of the element mounting portion 3.

絶縁層５は銅基板２の一面２ｂに接着層７により貼り合わされ銅基板２に積層されている。接着層７は、紙や布等の繊維材料からなるシートに熱硬化性の接着樹脂を含浸してなり、絶縁層５の通孔６に個別に連通する複数の孔を有している。これらの孔の円形の縁によって、図２及び図３で代表して示すように前記貼り合わせに伴い通孔６に挿入された素子取付け部３に向けて食み出した食み出し部７ａを形成することが好ましい。この食み出し部７ａはテーパ状周面３ｂに形成された周面メッキ部４ｂに連続している。 The insulating layer 5 is bonded to the one surface 2 b of the copper substrate 2 by the adhesive layer 7 and laminated on the copper substrate 2. The adhesive layer 7 is formed by impregnating a sheet made of a fiber material such as paper or cloth with a thermosetting adhesive resin, and has a plurality of holes individually communicating with the through holes 6 of the insulating layer 5. With the circular edges of these holes, as shown in FIG. 2 and FIG. 3, the protruding portion 7 a protruding toward the element mounting portion 3 inserted into the through hole 6 with the bonding is provided. It is preferable to form. The protruding portion 7a is continuous with the peripheral plating portion 4b formed on the tapered peripheral surface 3b.

なお、絶縁層５が銅基板２に接着される前の状態では、接着層７の孔の直径は通孔６の直径より多少大きいが、食み出し部７ａは、絶縁層５が銅基板２に接着されるに伴い形成される。これは、予め接着層７が貼り付けられた絶縁層５を銅基板２に押付けた状態のままで加熱炉に通して接着層７を加熱硬化することに伴い、前記押付けにより接着層７が圧縮されて変形することで、接着層７の孔が通孔６の直径より縮径されるからである。通孔６の内面６ａに対する食み出し部７aの食み出し寸法Ａは０．２ｍｍ以下である。この食み出し寸法Ａは、接着層７の厚み及び銅基板２への絶縁層５の押付け力の加減等により規定できる。 In the state before the insulating layer 5 is bonded to the copper substrate 2, the diameter of the hole of the adhesive layer 7 is slightly larger than the diameter of the through hole 6. It is formed as it is adhered to. This is because the insulating layer 5 to which the adhesive layer 7 has been applied in advance is pressed against the copper substrate 2 while being passed through a heating furnace to heat and cure the adhesive layer 7, and the pressing causes the adhesive layer 7 to be compressed. This is because the hole of the adhesive layer 7 is reduced in diameter than the diameter of the through hole 6 by being deformed. The protruding dimension A of the protruding portion 7a with respect to the inner surface 6a of the through hole 6 is 0.2 mm or less. This protrusion dimension A can be defined by the thickness of the adhesive layer 7 and the adjustment of the pressing force of the insulating layer 5 to the copper substrate 2.

複数の銅パターン８は、各ＬＥＤチップ１１への通電要素としてこれらＬＥＤチップ１１を直列に接続するために、絶縁層５の銅基板２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。これらの銅パターン８は、絶縁層５を銅基板２に貼り合わせる前に設けられる。 In order to connect the LED chips 11 in series as current-carrying elements to the LED chips 11, the plurality of copper patterns 8 are etched on the surface opposite to the back surface bonded to the copper substrate 2 of the insulating layer 5. It is formed by. These copper patterns 8 are provided before the insulating layer 5 is bonded to the copper substrate 2.

図１に示すように各銅パターン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。各列での複数の銅パターン８は所定ピッチで各通孔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銅パターン８には電線接続部９ａが一体に連続して形成されているとともに、同列の他端側に位置した銅パターン８には電線接続部９ｂが一体に連続して形成されている。これら電線接続部９ａ，９ｂの夫々は銅パターン８より幅広であって、これらには図示しない外部電源にいたる外部絶縁被覆電線が個別に半田付けされる。 As shown in FIG. 1, the copper patterns 8 are formed in two rows in the longitudinal direction of the insulating layer 5 at predetermined intervals. The plurality of copper patterns 8 in each row are alternately arranged with each through hole 6 at a predetermined pitch. The copper pattern 8 located on one end side of these rows is integrally formed with a wire connecting portion 9a, and the copper pattern 8 located on the other end side of the same row is continuously joined with a wire connecting portion 9b. Is formed. Each of these electric wire connecting portions 9a and 9b is wider than the copper pattern 8, and external insulation coated electric wires to an external power source (not shown) are individually soldered to these.

図２及び図３で代表して示すように各銅パターン８は、通孔６の縁には達しておらず、この通孔６の縁から所定距離隔てられている。銅パターン８の端８ａとこれに最も近接している通孔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。この露出した面（露出面）を符号５ａで示す。これにより、銅パターン８の端８ａと素子取付け部３との間の絶縁距離をより長く確保できるとともに、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 copper pattern 8 does not reach the edge of the through hole 6 but is separated from the edge of the through hole 6 by a predetermined distance. A part of the white insulating layer 5 is exposed between the end 8a of the copper pattern 8 and the edge of the through hole 6 closest to the end 8a. This exposed surface (exposed surface) is denoted by reference numeral 5a. Thereby, it is possible to secure a longer insulation distance between the end 8a of the copper pattern 8 and the element mounting portion 3, and it is possible to reflect the light incident on the exposed surface 5a in the light extraction direction.

各銅パターン８の表面にニッケル層としてのニッケルメッキ層３０を介して光反射層１０が形成されている。光反射層１０は、反射率が９０％以上の銀メッキ層からなる。この光反射層１０と前記銀メッキ層４は、無電解メッキ処理により一度に設けられる。前期ニッケルメッキ層３０は、銅パターン８の銅がマイグレーションにより銀メッキ層１０に侵入するのを抑制し、銀の反射率が低下するのを抑制している。 A light reflection layer 10 is formed on the surface of each copper pattern 8 via a nickel plating layer 30 as a nickel layer. The light reflecting layer 10 is made of a silver plating layer having a reflectance of 90% or more. The light reflecting layer 10 and the silver plating layer 4 are provided at a time by electroless plating. The first nickel plating layer 30 suppresses the copper of the copper pattern 8 from entering the silver plating layer 10 due to migration, and suppresses the silver reflectance from being lowered.

各ＬＥＤチップ１１は例えば青色の光を発する青色ＬＥＤチップ１１からなる。このＬＥＤチップ１１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で代表して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は反射膜を有しておらず、ＬＥＤチップ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 LED chip 11 includes a blue LED chip 11 that emits blue light, for example. The LED chip 11 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 representatively shown in FIG. Has been. The element substrate 12 is made of, for example, a sapphire substrate. The semiconductor light emitting layer 13 does not have a reflective film, and can emit light in both the thickness directions of the LED chip 11 and can also emit light from the side surface of the element substrate 12 to the side.

これらのＬＥＤチップ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の先端面３ａを覆っている銀メッキ層４の端面メッキ部４ａ上にダイボンドされている。それによって、各ＬＥＤチップ１１は各銅パターン８と交互に配置されている。ダイボンド材１６の厚みは０．１０ｍｍ以下である。ダイボンド材１６はＬＥＤチップ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。銅基板２の長手方向に交互に配置された銅パターン８とＬＥＤチップ１１とは、ワイヤボンディングにより設けられたボンディングワイヤ１７で電気的に直列に接続されている。 In these LED chips 11, the other surface parallel to the one surface of the element substrate 12 is covered with a tip end surface 3 a of each element mounting portion 3 using a die bond material 16 made of an adhesive such as a translucent silicone resin. It is die-bonded on the end plating portion 4 a of the plating layer 4. Thereby, each LED chip 11 is alternately arranged with each copper pattern 8. The thickness 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 LED chip 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. The copper patterns 8 and the LED chips 11 alternately arranged in the longitudinal direction of the copper substrate 2 are electrically connected in series by bonding wires 17 provided by wire bonding.

ＬＥＤチップ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。半導体発光層１３の高さ位置を銅パターン８表面の光反射層１０より高く位置させるために、本実施形態ではＬＥＤチップ１１全体が銅パターン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 LED chip 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. In order to position the height position of the semiconductor light emitting layer 13 higher than the light reflecting layer 10 on the surface of the copper pattern 8, the entire LED chip 11 is positioned higher than the light reflecting layer 10 on the surface of the copper pattern 8 in this embodiment.

こうした高さの差によって、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１７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１７の他端を銅パターン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１７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, one end of the bonding wire 17 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 17 is bonded to the copper pattern 8. At this time, the insulating layer 5 is unlikely to obstruct the movement of the bonding tool of the bonding machine, and the bonding wire 17 is not forcibly pulled downward, so that wire bonding is easy.

更に、本実施形態のようにＬＥＤチップ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、ＬＥＤチップ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、通孔６の周辺に差し込み易い。それにより、ＬＥＤチップ１１のまわ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。なお、本発明では、一つの素子取付け部３に一個のＬＥＤチップ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ＬＥＤチップ１１を並べて取付けることも可能である。その場合、同じ色の光を発する複数個のＬＥＤチップ１１であっても、或いは異なる色の光を発する複数個のＬＥＤチップ１１であってもよく、異なる色の光を発する複数個のＬＥＤチップ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ＬＥＤチップ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ＬＥＤチップ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。 Furthermore, in the preferred configuration in which the entire LED chip 11 is disposed at a position higher than the surface of the insulating layer 5 as in the present embodiment, light emitted from the LED chip 11 to the surroundings is blocked by the insulating layer 5. It is easy to insert in the periphery of the through-hole 6 without. Thereby, light can be extracted around the LED chip 11 by reflecting light, which is advantageous in that the light extraction efficiency can be increased. In the present invention, it is not limited to mounting one LED chip 11 on one element mounting portion 3, and a plurality of LED chips 11 can be mounted side by side on one element mounting portion 3. . In that case, it may be a plurality of LED chips 11 that emit light of the same color or a plurality of LED chips 11 that emit light of different colors, and a plurality of LED chips that emit light of different colors. When 11 is mounted on one element mounting portion 3, three LED chips 11 emitting red, yellow and blue light can be mounted side by side. In the configuration in which a plurality of LED chips 11 are mounted side by side on one element mounting portion 3, the total luminous flux of the lighting device 1 can be improved.

以上のように銀メッキ層４が略全体に形成された素子取付け部３を有した銅基板２、光反射層１０を有した銅パターン８付きの絶縁層５、ＬＥＤチップ１１、ボンディングワイヤ１７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 copper substrate 2 having the element mounting portion 3 in which the silver plating layer 4 is formed almost entirely, the insulating layer 5 with the copper pattern 8 having the light reflection layer 10, the LED chip 11, and the bonding wire 17. A planar light source of the lighting device 1 is formed.

リフレクタ２０は、一個一個又は数個のＬＥＤチップ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ＬＥＤチップ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９ａ，９ｂは外部絶縁被覆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。 The reflector 20 is not individually provided for each one or several LED chips 11, but is a single one that surrounds all the LED chips 11 on the insulating layer 5, and has a frame, for example, shown in FIG. Thus, it is formed with a rectangular frame. The reflector 20 is bonded to the insulating layer 5. The electric wire connecting portions 9a and 9b are located outside the reflector 20 in order to connect an external insulation covered electric wire.

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酸化アルミニウム等の白色粉末(図示しない)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、投光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 inner peripheral surface of the reflector 20 is a light reflecting surface. Therefore, for example, a white powder (not shown) such as aluminum oxide is mixed in a 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 projection target.

封止部材２２は、リフレクタ２０内に未硬化の状態で注入された後硬化されたものであり、前記面状発光源を埋めている。この封止部材２２は絶縁層５の通孔６内に充填されている。それにより、封止部材２２は、銀メッキ層４で覆われた素子取付け部３のテーパ状周面３ｂ及び食み出し部７ａに通孔６内で接してこれらを覆っている。封止部材２２は、熱硬化性の透光性材料例えば透明シリコーン樹脂からなり、その内部に蛍光体(図示しない)が混入されている。本実施形態では白色系の照明光を得るために、ＬＥＤチップ１１が発する光(具体的に青色の光)の一部により励起されて、このＬＥＤチップ１１が発する光とは異なる色の光(具体的には黄色の光)を放射する蛍光体が用いられ、この蛍光体は好ましくは略均一に分散した状態で封止部材２２内に混入されている。 The sealing member 22 is injected into the reflector 20 in an uncured state and then cured, and fills the planar light source. The sealing member 22 is filled in the through hole 6 of the insulating layer 5. Thereby, the sealing member 22 is in contact with and covers the tapered peripheral surface 3 b and the protruding portion 7 a of the element mounting portion 3 covered with the silver plating layer 4 in the through hole 6. The sealing member 22 is made of a thermosetting translucent material such as a transparent silicone resin, and a phosphor (not shown) is mixed therein. In the present embodiment, in order to obtain white illumination light, light that is excited by a part of light emitted from the LED chip 11 (specifically, blue light) and has a color different from that emitted from the LED chip 11 ( Specifically, a phosphor that emits yellow light) is used, and this phosphor is preferably mixed in the sealing member 22 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光の混合によって照明装置１は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。そのため、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できる。 With 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 excited. Thus, yellow light is emitted, and this yellow light passes through the sealing member 22, so that the lighting device 1 can irradiate white light by mixing these two colors of complementary colors. 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. Therefore, there is little light loss caused by reflection, and the light extraction efficiency can be improved.

以上の構成の照明装置１は、各ＬＥＤチップ１１に通電して、これらＬＥＤチップ１１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。この点灯時に各ＬＥＤチップ１１は発熱する。 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 LED chip 11 and causing the LED chips 11 to emit light. Each LED chip 11 generates heat during the lighting.

ところで、ＬＥＤチップ１１に電力を導く銅パターン８は、絶縁層５により銅基板２に対して電気的に絶縁されているが、絶縁層５は銅基板２とＬＥＤチップ１１との間には介在されていないとともに、ＬＥＤチップ１１は銅基板２の素子取付け部３上に直接的にダイボンドされている。 By the way, the copper pattern 8 for guiding power to the LED chip 11 is electrically insulated from the copper substrate 2 by the insulating layer 5, but the insulating layer 5 is interposed between the copper substrate 2 and the LED chip 11. In addition, the LED chip 11 is directly die-bonded on the element mounting portion 3 of the copper substrate 2.

そのため、各ＬＥＤチップ１１が発する熱は、絶縁層５に邪魔されることなく銅基板２に直接的に伝導する。より具体的には、ＬＥＤチップ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、銀メッキ層４及びニッケルメッキ層３０を経て銅基板２の素子取付け部３に伝えられる。しかも、素子取付け部３は、ＬＥＤチップ１１がダイボンドされた先端面３ａから銅基板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、ＬＥＤチップ１１から基板主部２ａに向けての熱伝導がより容易となる。そして、銅基板２の熱はこの銅基板２の背面２ｃから外部に放出される。 Therefore, the heat generated by each LED chip 11 is directly conducted to the copper substrate 2 without being disturbed by the insulating layer 5. More specifically, the heat of the LED chip 11 passes through the die bonding material 16 that is so thin that it does not substantially become a thermal resistance, and then passes through the silver plating layer 4 and the nickel plating layer 30, and the element mounting portion 3 of the copper substrate 2. To be told. In addition, the element mounting portion 3 gradually becomes thicker from the tip surface 3a to which the LED chip 11 is die-bonded to the substrate main portion 2a of the copper substrate 2. In other words, the cross-sectional area of the element mounting portion 3 approaches the substrate main portion 2a. Since it becomes so large, the heat conduction from the LED chip 11 toward the substrate main part 2a becomes easier. The heat of the copper substrate 2 is released from the back surface 2c of the copper substrate 2 to the outside.

こうしてＬＥＤチップ１１の熱が高効率に銅基板２を通って外部に放出されるので、各ＬＥＤチップ１１の温度上昇が効果的に抑制され、各ＬＥＤチップ１１の温度を設計通りに維持できる。そのため、各ＬＥＤチップ１１の発光効率の低下と、各ＬＥＤチップ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ＬＥＤチップ１１の発光色のむらを抑制できる。又、前記構成の各ＬＥＤチップ１１は全方向に光を放射し、取分け、正面方向つまり銅基板２とは反対側の光の取出し方向に放射される光よりも、背面方向つまり銅基板２に向けて放射される光の方が強い。 Thus, the heat of the LED chip 11 is released to the outside through the copper substrate 2 with high efficiency, so that the temperature rise of each LED chip 11 is effectively suppressed, and the temperature of each LED chip 11 can be maintained as designed. Therefore, a decrease in the light emission efficiency of each LED chip 11 and a variation in the amount of light emitted from each LED chip 11 are suppressed, and as a result, unevenness in the light emission color of each LED chip 11 can be suppressed. Further, each LED chip 11 having the above configuration emits light in all directions, and in particular, the light is emitted in the back direction, that is, the copper substrate 2 rather than the light emitted in the front direction, that is, the light extraction direction opposite to the copper substrate 2. The light emitted toward it is stronger.

そして、背面方向に放射された光の多くは、透光性のダイボンド材１６を通って９０％以上の光反射率を有した銀メッキ層４の端面メッキ部４ａに入射し、この端面メッキ部４ａで光の取出し方向に反射される。このようなＬＥＤチップ１１直下での高効率の反射により、光の取出し効率をより向上させることができる。 And most of the light radiated in the back direction passes through the translucent die-bonding material 16 and is incident on the end plating portion 4a of the silver plating layer 4 having a light reflectance of 90% or more. 4a is reflected in the light extraction direction. Such high-efficiency reflection directly under the LED chip 11 can further improve the light extraction efficiency.

しかも、前記背面２ｃ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、背面２ｃ方向に向かった光の一部は銅パターン８を覆った光反射層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。 In addition, a part of the light emitted in the direction of the back surface 2 c 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 surface 2 c is incident on the light reflecting layer 10 covering the copper pattern 8, and is reflected by the light reflecting layer 10 in the light extraction direction.

更に、絶縁層５の通孔６の周辺は、その一部が銅パターン８で覆われることがなく、この銅パターン８と通孔６との間おいて露出面５ａを有している。言い換えれば、通孔６の周辺を、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。それだけではなく、点灯時に、封止部材２２中の蛍光体から放射された光の一部を、素子取付け部３によって光の取出し方向に反射させることができる。詳しくは、素子取付け部３のテーパ状周面３ｂに対して絶縁層５の通孔６の内面６ａは離れていて、これらの間に封止部材２２の一部が充填された状態にある。そのため、封止部材２２中の蛍光体から放射された光の一部は、素子取付け部３の先端面３ａの内でＬＥＤチップ１１の周囲だけではなく、絶縁層５で妨げられることなくテーパ状周面３ｂにも入射可能である。言い換えれば、素子取付け部３での反射面積が、先端面３ａの内でＬＥＤチップ１１の周囲以外にテーパ状周面３ｂにも確保されている。そして、このテーパ状周面３ｂでの反射面積は、先端面３ａの内でＬＥＤチップ１１の周囲の反射面積よりも大きい。 Furthermore, the periphery of the through hole 6 of the insulating layer 5 is not partially covered with the copper pattern 8, and has an exposed surface 5 a between the copper pattern 8 and the through hole 6. In other words, since the periphery of the through-hole 6 can be regarded as a continuous white reflecting surface without being interrupted along the circumferential direction, the light incident thereon can be reflected in the light extraction direction. In addition, at the time of lighting, a part of the light emitted from the phosphor in the sealing member 22 can be reflected in the light extraction direction by the element mounting portion 3. Specifically, the inner surface 6a of the through hole 6 of the insulating layer 5 is separated from the tapered peripheral surface 3b of the element mounting portion 3, and a part of the sealing member 22 is filled therebetween. Therefore, a part of the light radiated from the phosphor in the sealing member 22 is tapered not only by the periphery of the LED chip 11 but also by the insulating layer 5 in the tip surface 3 a of the element mounting portion 3. It can also enter the peripheral surface 3b. In other words, the reflection area at the element mounting portion 3 is also secured on the tapered peripheral surface 3b in addition to the periphery of the LED chip 11 in the tip surface 3a. And the reflective area in this taper-shaped surrounding surface 3b is larger than the reflective area around the LED chip 11 in the front end surface 3a.

こうした条件に加えて、素子取付け部３の反射面として機能する先端面３ａ及びテーパ状周面３ｂは、光反射率が９０％以上と高い銀メッキ層４で覆われている。そのため、テーパ状周面３ｂに入射した光を、効率よく光の取出し方向に反射させることができる。なお、テーパ状周面３ｂに対する銀メッキ層４の周面メッキ部４ｂの形成面積が、銅基板２に絶縁層５を固定する接着層７の食み出し部７ａによって減少することは、この食み出し部７ａの食み出し寸法が０．２ｍｍ以下と極小であることにより、実質的に無視できる。これとともに、接着層７の色が黒色等の白色系以外の色である場合、食み出し部７による光の吸収も実質的に無視できる。このように食み出し部７ａは、照明装置１の光の出射方向に取出される光の取出し効率を向上させる上で、実質的な支障とならないものである。 In addition to these conditions, the tip surface 3a and the tapered peripheral surface 3b functioning as the reflection surface of the element mounting portion 3 are covered with a silver plating layer 4 having a high light reflectance of 90% or more. Therefore, the light incident on the tapered peripheral surface 3b can be efficiently reflected in the light extraction direction. Note that the formation area of the peripheral plating portion 4b of the silver plating layer 4 with respect to the tapered peripheral surface 3b is reduced by the protruding portion 7a of the adhesive layer 7 that fixes the insulating layer 5 to the copper substrate 2. Since the protruding dimension of the protruding portion 7a is as small as 0.2 mm or less, it can be substantially ignored. At the same time, when the color of the adhesive layer 7 is a color other than white, such as black, light absorption by the protruding portion 7 can be substantially ignored. As described above, the protrusion 7a does not substantially hinder the improvement of the extraction efficiency of light extracted in the light emission direction of the lighting device 1.

したがって、前記構成の照明装置１は、ＬＥＤチップ１１の放熱を促進させる素子取付け部３を利用して、照明装置１の光の出射方向に取出される光の取出し効率を向上させることができる。ちなみに、素子取付け部３に銀メッキ層を設けない構成の照明装置の全光束を１００とした場合に比較して、前記構成の照明装置１での全光束は１１０であることが、本発明者による比較試験で明らかになった。 Therefore, the illumination device 1 having the above-described configuration can improve the light extraction efficiency of the illumination device 1 extracted in the light emission direction by using the element mounting portion 3 that promotes heat dissipation of the LED chip 11. Incidentally, the present inventor shows that the total luminous flux of the illumination device 1 having the above-described configuration is 110 as compared with the case where the total luminous flux of the illumination device having the configuration in which the element mounting portion 3 is not provided with the silver plating layer is 100. It became clear in the comparative test by.

又、既述のように接着層７は素子取付け部３の根元方向へ突出した食み出し部７ａを有しているから、封止部材２２による封止に伴って封止部材２２内に気泡が残留しないようにできる。即ち、封止部材２２は、未硬化の状態でリフレクタ２０内に所定量注入された後に、加熱炉によって加熱されることで硬化して、ＬＥＤチップ１１等を封止する。この場合、リフレクタ２０内に空気溜りがあると、そこに溜まっていた空気が、加熱に伴って未硬化の封止部材２２内に流出して、それが抜けきらない内に封止部材２２が硬化することにより、気泡となって封止部材２２内に残留することがある。そのため、封止部材２２を設ける前の状態で、接着層７が絶縁層５の通孔６の内面６ａに対して素子取付け部３から遠ざかるように引っ込んでいる場合には、絶縁層５と銅基板２との間に通孔６に連通する空気溜りが形成される。 Further, as described above, since the adhesive layer 7 has the protruding portion 7 a protruding in the root direction of the element mounting portion 3, there is a bubble in the sealing member 22 along with the sealing by the sealing member 22. Can be prevented from remaining. That is, the sealing member 22 is injected by a predetermined amount into the reflector 20 in an uncured state and then cured by being heated by a heating furnace to seal the LED chip 11 and the like. In this case, if there is an air reservoir in the reflector 20, the air accumulated in the reflector 20 flows into the uncured sealing member 22 with heating, and the sealing member 22 is not fully removed. By curing, bubbles may remain in the sealing member 22. Therefore, when the adhesive layer 7 is retracted away from the element mounting portion 3 with respect to the inner surface 6a of the through hole 6 of the insulating layer 5 before the sealing member 22 is provided, the insulating layer 5 and the copper An air pocket communicating with the through hole 6 is formed between the substrate 2 and the substrate 2.

しかし、照明装置１は既述のように素子取付け部３の根元方向へ突出する接着層７の食み出し部７ａを有しているから、リフレクタ２０内に空気溜りが形成されることがない。したがって、加熱されることにより硬化する封止部材２２内に気泡が残留することを抑制できる。そのため、封止部材２２内に水が溜まって、封止部材２２の絶縁性能の低下がもたらされないようにできる。 However, since the lighting device 1 has the protruding portion 7a of the adhesive layer 7 protruding in the root direction of the element mounting portion 3 as described above, no air pocket is formed in the reflector 20. . Therefore, it is possible to suppress the bubbles from remaining in the sealing member 22 that is cured by being heated. Therefore, it is possible to prevent water from accumulating in the sealing member 22 and reducing the insulation performance of the sealing member 22.

なお、接着層７が黒色系である場合、その食み出し部７ａと白色の絶縁層５の通孔６の内面６ａとのコントラストが明確である。そのため、銅パターン８にボンディングワイヤ１７をワイヤボンディングする場合のＣＣＤカメラでの視認に基づく位置決めの基準を、食み出し部７ａと通孔６の内面６ａとの境界に求めることができるので、低解像度のＣＣＤカメラでも前記位置決め基準を確実に視認することが可能である。 When the adhesive layer 7 is black, the contrast between the protruding portion 7a and the inner surface 6a of the through hole 6 of the white insulating layer 5 is clear. Therefore, the positioning reference based on the visual recognition with the CCD camera when the bonding wire 17 is wire bonded to the copper pattern 8 can be obtained at the boundary between the protruding portion 7a and the inner surface 6a of the through hole 6. Even with a CCD camera having a resolution, the positioning reference can be reliably recognized.

本発明の第１実施形態に係る照明装置を一部切欠いて示す正面図。FIG. 2 is a front view showing the lighting device according to the first 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.

Explanation of symbols

１…照明装置、２…銅基板、２ａ…基板主部、３…素子取付け部、３ａ…素子取付け部の先端面、３ｂ…素子取付け部のテーパ状周面、４…銀層、４ａ…端面メッキ部、４ｂ…周面メッキ部、５…絶縁層、６…通孔、７…接着層、７ａ…接着層の食み出し部、８…銅パターン、１１…ＬＥＤチップ（半導体発光素子）、１２…素子基板、１３…半導体発光層、１６…ダイボンド材、１７…ボンディングワイヤ、２２…封止部材、３０…ニッケル層。 DESCRIPTION OF SYMBOLS 1 ... Illuminating device, 2 ... Copper substrate, 2a ... Substrate main part, 3 ... Element attachment part, 3a ... Tip surface of element attachment part, 3b ... Tapered peripheral surface of element attachment part, 4 ... Silver layer, 4a ... End face Plated portion, 4b ... peripheral plating portion, 5 ... insulating layer, 6 ... through hole, 7 ... adhesive layer, 7a ... protruding portion of adhesive layer, 8 ... copper pattern, 11 ... LED chip (semiconductor light emitting element), DESCRIPTION OF SYMBOLS 12 ... Element substrate, 13 ... Semiconductor light emitting layer, 16 ... Die bond material, 17 ... Bonding wire, 22 ... Sealing member, 30 ... Nickel layer.

Claims

A copper substrate having one surface and an element mounting portion formed integrally with a convex portion on the one surface, wherein the element mounting portion is gradually formed thicker from the tip surface to the one surface;
A nickel layer formed on the tip end surface of the element mounting portion and a tapered peripheral surface extending continuously to the one surface;
A silver layer formed on the nickel layer;
An insulating layer having a through hole into which the element mounting portion is inserted and laminated by adhering to one surface of the copper substrate with an adhesive layer;
A copper pattern provided on the insulating layer;
A nickel layer formed on the copper pattern;
A silver layer formed on the nickel layer;
A semiconductor light emitting device die-bonded to a silver layer covering the tip surface of the device mounting portion;
A bonding wire connecting the semiconductor light emitting element and the conductor;
A translucent seal in which a phosphor that is excited by a part of light emitted from the semiconductor light emitting device and emits light of different colors is mixed, and the device mounting portion, the semiconductor light emitting device, and a bonding wire are embedded With members;
An illumination device comprising:

The adhesive layer has a protruding portion in the root direction of the element mounting portion, the protruding size of the protruding portion with respect to the inner surface of the through hole is 0.2 mm or less, and the tapered peripheral surface The illuminating device according to claim 1, wherein a silver layer formed on the protrusion is continuous with the protruding portion.