JP4585014B2

JP4585014B2 - Light emitting device

Info

Publication number: JP4585014B2
Application number: JP2008145862A
Authority: JP
Inventors: 士郎酒井; 金平敖; 泰夫大野
Original assignee: Seoul Semiconductor Co Ltd
Current assignee: Seoul Semiconductor Co Ltd
Priority date: 2002-04-12
Filing date: 2008-06-03
Publication date: 2010-11-24
Anticipated expiration: 2022-08-29
Also published as: JP2009182358A; JP2009182357A; JP4585028B2; JP2009296011A; JP2009296012A; JP4939584B2; JP2012089887A; JP2009296013A; JP4938822B2; JP2009182356A; JP4938821B2; JP5524881B2; JP2009182355A; JP2009267423A; JP2008211255A; JP2011109143A

Description

本発明は、基板上に複数の発光素子が形成された発光装置に関する。 The present invention relates to a light emitting device in which a plurality of light emitting elements are formed on a substrate.

発光素子（ＬＥＤ）等の発光手段が表示用途等に使用される場合には、その使用条件が駆動電圧約１〜４Ｖ、駆動電流が約２０ｍＡとなっている。ところで、近年ＧａＮ系化合物半導体を用いた短波長ＬＥＤが開発され、フルカラーや白色等の固体光源が実用化されたことに伴い、次第にＬＥＤを照明用途にも応用することが検討されている。ＬＥＤを照明用途に応用する場合に、上述した駆動電圧１〜４Ｖ、駆動電流２０ｍＡという使用条件とは異なる条件で使用される事態も生じる。このため、ＬＥＤにより大電流を流し、発光出力を大きくする工夫がなされている。大電流を流すためには、ＬＥＤのｐｎ接合面積を大きくし、電流密度を小さく抑える必要がある。 When a light emitting means such as a light emitting element (LED) is used for a display application or the like, the use conditions are a drive voltage of about 1 to 4 V and a drive current of about 20 mA. By the way, with the recent development of short-wavelength LEDs using GaN-based compound semiconductors and the practical use of solid-state light sources such as full color and white, it has been studied to gradually apply LEDs to lighting applications. When the LED is applied to lighting applications, there is a situation in which the LED is used under conditions different from the use conditions of the drive voltage of 1 to 4 V and the drive current of 20 mA. For this reason, a device has been devised in which a large current is passed through the LED to increase the light emission output. In order to flow a large current, it is necessary to increase the pn junction area of the LED and reduce the current density.

特開２００１−３０７５０６号公報JP 2001-307506 A 特開昭５９−２０６８７３号公報JP 59-206873 A

ＬＥＤを照明用光源として使用する場合には、電源として交流を使用し、１００Ｖ以上の駆動電圧で使用できることが便利である。また、同じ電力を投入して同じ発光出力を得るのであれば、低い電流値を保ちながら高い電圧を印加した方が電力損失を小さくすることができる。しかし、従来のＬＥＤでは、必ずしも十分に駆動電圧を高くすることはできなかった。 When using an LED as a light source for illumination, it is convenient that an alternating current is used as a power source and it can be used at a driving voltage of 100 V or more. If the same light output is obtained by applying the same power, the power loss can be reduced by applying a high voltage while maintaining a low current value. However, in the conventional LED, the drive voltage cannot always be sufficiently increased.

本発明は、上記従来技術の有する課題に鑑みなされたものであり、その目的は、高い駆動電圧で動作できる発光装置を提供することにある。 The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide a light-emitting device that can operate at a high driving voltage.

本発明は、絶縁基板上に複数のＧａＮ系発光ダイオード素子を形成してなる発光装置であって、前記複数の発光ダイオード素子は前記絶縁基板上に、マトリクス状に配置され、前記複数の発光ダイオード素子は、互いに反対極性として第１の組と第２の組とに電気的に分けられるように２個の交流電源用電極に並列接続され、前記第１の組の発光ダイオード素子が第１の発光ダイオード素子の列と第２の発光ダイオード素子の列とを含み、前記第２の組の発光ダイオード素子が第３の発光ダイオード素子の列と第４の発光ダイオード素子の列とを含み、前記第３の発光ダイオード素子の列が前記第１の発光ダイオード素子の列と前記第２の発光ダイオード素子の列との間に配置され、前記第１の発光ダイオード素子の列の前記マトリクス状の配列の１辺側の端部の発光ダイオード素子の電極と、前記第２の発光ダイオード素子の列の前記１辺側の端部の発光ダイオード素子の電極と、前記第３の発光ダイオード素子の列の前記１辺側の端部の発光ダイオード素子の電極と、前記第４の発光ダイオード素子の列の前記１辺側の端部の発光ダイオード素子の電極とが共有されて電気的に接続され、かつ、前記２個の交流電源用電極とは直接には接続されていないことを特徴とする。
The present invention is a light-emitting device in which a plurality of GaN-based light-emitting diode elements are formed on an insulating substrate, wherein the plurality of light-emitting diode elements are arranged in a matrix on the insulating substrate, and the plurality of light-emitting diodes The elements are connected in parallel to the two AC power supply electrodes so as to be electrically divided into a first set and a second set with opposite polarities, and the first set of light emitting diode elements is a first set. A column of light emitting diode elements and a column of second light emitting diode elements, wherein the second set of light emitting diode elements includes a column of third light emitting diode elements and a column of fourth light emitting diode elements; A third light emitting diode element row is disposed between the first light emitting diode element row and the second light emitting diode element row, and the matrix of the first light emitting diode element rows. The electrode of the light emitting diode element at the end of one side of the row, the electrode of the light emitting diode element at the end of the first side of the row of the second light emitting diode device, and the row of the third light emitting diode element The electrode of the light emitting diode element at the end on the one side and the electrode of the light emitting diode element at the end on the one side of the column of the fourth light emitting diode elements are shared and electrically connected , and, said the two AC power supply electrode directly is characterized in that no Tei is connected.

また、本発明は、前段落記載の発光装置において、さらに前記第１の列を構成する発光ダイオード素子の前記マトリクス上の配置の１辺の側の端部の発光ダイオード素子の第１の電極と、前記第２の列を構成する発光ダイオード素子の前記１辺の側の端部の発光ダイオード素子の第２の電極と、前記第３の列を構成する発光ダイオード素子の前記１辺の側の端部の発光ダイオード素子の第３の電極と、前記第４の列を構成する発光ダイオード素子の前記１辺の側の端部の発光ダイオード素子の第４の電極とがそれぞれ共有され、電気的に接続され、前記第１の電極と前記第４の電極とは同じ極性であり、前記第２の電極と前記第３の電極とは同じ極性であり、前記第１の電極及び前記第４の電極と前記第２の電極及び前記第３の電極の極性は異なることを特徴とする発光装置を提供する。 According to the present invention, in the light-emitting device described in the preceding paragraph, the first electrode of the light-emitting diode element at the end on one side of the arrangement of the light-emitting diode elements constituting the first column on the matrix; , The second electrode of the light emitting diode element at the end of the one side of the light emitting diode element constituting the second row, and the one side of the light emitting diode element constituting the third row. The third electrode of the light emitting diode element at the end and the fourth electrode of the light emitting diode element at the end on the one side of the light emitting diode elements constituting the fourth row are shared, respectively, The first electrode and the fourth electrode have the same polarity, the second electrode and the third electrode have the same polarity, and the first electrode and the fourth electrode The polarities of the electrode, the second electrode, and the third electrode are It becomes possible to provide a light emitting device according to claim.

本発明によれば、高い駆動電圧で駆動し発光させることができる。 According to the present invention, light can be emitted by driving at a high driving voltage.

以下、図面に基づき本発明の実施形態について説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

図１には、本実施形態においてＧａＮ系化合物半導体発光素子としてのＬＥＤ１の基本構成が示されている。ＬＥＤ１は、基板１０上に順次ＧａＮ層１２、Ｓｉドープのｎ型ＧａＮ層１４、ＩｎＧａＮ発光層１６、ＡｌＧａＮ層１８、ｐ型ＧａＮ層２０が積層され、ｐ型ＧａＮ層２０に接してｐ電極２２、ｎ型ＧａＮ層１４に接してｎ電極２４が形成される構成である。 FIG. 1 shows a basic configuration of an LED 1 as a GaN-based compound semiconductor light-emitting element in the present embodiment. In the LED 1, a GaN layer 12, a Si-doped n-type GaN layer 14, an InGaN light emitting layer 16, an AlGaN layer 18, and a p-type GaN layer 20 are sequentially stacked on a substrate 10, and a p-electrode 22 is in contact with the p-type GaN layer 20. The n electrode 24 is formed in contact with the n-type GaN layer 14.

図１に示されたＬＥＤは以下のプロセスにより作製される。すなわち、まず、ＭＯＣＶＤ装置にてサファイアｃ面基板を水素雰囲気中で１１００℃、１０分間熱処理する。そして、温度を５００℃まで降温させ、シランガスとアンモニアガスを１００秒間供給して不連続なＳｉＮ膜を基板１０上に形成する。なお、このプロセスはデバイス中の転位密度を低減させるためのものであり、図ではＳｉＮ膜は省略している。次に、同一温度でトリメチルガリウム及びアンモニアガスを供給してＧａＮ層を２０ｎｍ厚成長させる。温度を１０５０℃に昇温し、再びトリメチルガリウム及びアンモニアガスを供給してアンドープＧａＮ（ｕ−ＧａＮ）層１２及びＳｉドープのｎ型ＧａＮ層１４を各２μｍ厚成長させる。その後、温度を７００℃程度まで降温してＩｎＧａＮ発光層１６を２ｎｍ厚成長させる。目標組成はｘ＝０．１５、すなわちＩｎ０．１５Ｇａ０．８５Ｎである。発光層１６成長後、温度を１０００℃まで昇温してＡｌＧａＮ正孔注入層１８を成長させ、さらにｐ型ＧａＮ層２０を成長させる。 The LED shown in FIG. 1 is manufactured by the following process. That is, first, a sapphire c-plane substrate is heat-treated in a hydrogen atmosphere at 1100 ° C. for 10 minutes by a MOCVD apparatus. Then, the temperature is lowered to 500 ° C., silane gas and ammonia gas are supplied for 100 seconds, and a discontinuous SiN film is formed on the substrate 10. This process is for reducing the dislocation density in the device, and the SiN film is omitted in the figure. Next, trimethylgallium and ammonia gas are supplied at the same temperature to grow a GaN layer to a thickness of 20 nm. The temperature is raised to 1050 ° C., and trimethylgallium and ammonia gas are supplied again to grow the undoped GaN (u-GaN) layer 12 and the Si-doped n-type GaN layer 14 to a thickness of 2 μm each. Thereafter, the temperature is lowered to about 700 ° C., and the InGaN light emitting layer 16 is grown to a thickness of 2 nm. The target composition is x = 0.15, ie In0.15Ga0.85N. After the light emitting layer 16 is grown, the temperature is raised to 1000 ° C. to grow the AlGaN hole injection layer 18 and further the p-type GaN layer 20 is grown.

ｐ型ＧａＮ層２０を成長させた後、ウエハをＭＯＣＶＤ装置から取り出し、Ｎｉ１０ｎｍ厚、Ａｕ１０ｎｍ厚を順次真空蒸着で成長層表面に形成する。５％の酸素を含む窒素ガス雰囲気中で５２０℃熱処理することで金属膜はｐ型透明電極２２となる。透明電極形成後、全面にフォトレジストを塗布し、ｎ型電極形成のためのエッチングをフォトレジストをマスクとして行う。エッチング深さは、例えば６００ｎｍ程度である。エッチングで露出したｎ型ＧａＮ層１４上にＴｉ５ｎｍ厚、Ａｌ５ｎｍ厚を形成し、窒素ガス雰囲気中で４５０℃、３０分間熱処理してｎ型電極２４を形成する。最後に、基板１０の裏面を１００μｍまで研磨してチップを切り出し、マウントすることでＬＥＤ１が得られる。 After the p-type GaN layer 20 is grown, the wafer is taken out from the MOCVD apparatus, and Ni 10 nm thickness and Au 10 nm thickness are sequentially formed on the growth layer surface by vacuum deposition. The metal film becomes the p-type transparent electrode 22 by heat treatment at 520 ° C. in a nitrogen gas atmosphere containing 5% oxygen. After forming the transparent electrode, a photoresist is applied to the entire surface, and etching for forming the n-type electrode is performed using the photoresist as a mask. The etching depth is, for example, about 600 nm. Ti 5 nm thickness and Al 5 nm thickness are formed on the n-type GaN layer 14 exposed by etching, and an n-type electrode 24 is formed by heat treatment at 450 ° C. for 30 minutes in a nitrogen gas atmosphere. Finally, the back surface of the substrate 10 is polished to 100 μm, the chip is cut out, and mounted to obtain the LED 1.

図１では、基板１０上に一つのＬＥＤ１が形成されているが、本実施形態では、基板１０上にＬＥＤ１をモノリシックに、かつ二次元アレイ状に複数形成し、各ＬＥＤを接続して発光装置（チップ）を構成する。 In FIG. 1, one LED 1 is formed on the substrate 10, but in this embodiment, a plurality of LEDs 1 are formed monolithically and in a two-dimensional array on the substrate 10, and each LED is connected to form a light emitting device. (Chip).

図２には、発光装置の等価回路図が示されている。図２において、２次元アレイ状に形成された発光素子群は同数（図では４個）ずつ２組に分けられ、各組のＬＥＤ１はそれぞれ直列接続され、２組のＬＥＤ列は電極（駆動電極）に対して逆極性となるように並列接続される。このようにＬＥＤ列が直列接続されることにより、各々の駆動電圧が加算された高い電圧でＬＥＤ１を駆動することができる。また、各ＬＥＤ列はその極性が互いに反対となるように電極に並列接続されているので、電源として交流電源を使用した場合にも、電源の各周期中に必ずどちらかのＬＥＤ列が発光していることになるので、効率のよい発光を行うことができる。 FIG. 2 shows an equivalent circuit diagram of the light emitting device. In FIG. 2, the light emitting element groups formed in a two-dimensional array are divided into two sets of the same number (four in the figure), each set of LEDs 1 is connected in series, and two sets of LED rows are electrodes (drive electrodes). ) Are connected in parallel so as to have a reverse polarity. Thus, by connecting the LED strings in series, the LED 1 can be driven with a high voltage obtained by adding the drive voltages. In addition, since each LED string is connected in parallel to the electrodes so that the polarities are opposite to each other, even when an AC power source is used as a power source, one of the LED columns always emits light during each cycle of the power source. Therefore, efficient light emission can be performed.

図３には、基板１０上にモノリシックに形成された複数のＬＥＤの部分的な平面図が示されている。また、図４は、図３のＩＶ−ＩＶ断面図が示されている。図３において、ＬＥＤ１の上面には、図１に示されるようにｐ電極２２及びｎ電極２４が形成されている。隣接するＬＥＤ１のｐ電極２２とｎ電極２４との間がエアブリッジ配線２８により接続され、複数のＬＥＤ１が直列接続される。 FIG. 3 shows a partial plan view of a plurality of LEDs monolithically formed on the substrate 10. FIG. 4 is a sectional view taken along the line IV-IV in FIG. In FIG. 3, a p-electrode 22 and an n-electrode 24 are formed on the upper surface of the LED 1 as shown in FIG. The p-electrode 22 and the n-electrode 24 of the adjacent LEDs 1 are connected by an air bridge wiring 28, and a plurality of LEDs 1 are connected in series.

図４において、各ＬＥＤ１は説明の都合上簡略的に示されている。すなわち、ｎ−ＧａＮ層１４、ｐ−ＧａＮ層２０、ｐ−電極２２、ｎ−電極２４のみが示されている。実際には図１に示されるようにＩｎＧａＮ発光層１６等が存在することは云うまでもない。エアブリッジ配線２８は、ｐ電極２２からｎ電極２４までを空中を介して接続する。これにより、素子表面に絶縁膜を塗布し、この上に電極を形成してｐ電極２２とｎ電極２４とを電気的に接続する方法に比べ、エッチング溝に沿って電極を配置する必要が無くなるので、配線切れや絶縁膜からｎ層、ｐ層へ絶縁材料を構成する元素が熱拡散してＬＥＤ１を劣化させるという問題を回避できる。エアブリッジ配線２８は、ＬＥＤ１間のみならずＬＥＤ１と図示しない電極との間の接続にも使用される。 In FIG. 4, each LED 1 is simply shown for convenience of explanation. That is, only the n-GaN layer 14, the p-GaN layer 20, the p-electrode 22, and the n-electrode 24 are shown. Needless to say, an InGaN light emitting layer 16 or the like actually exists as shown in FIG. The air bridge wiring 28 connects the p electrode 22 to the n electrode 24 through the air. As a result, it is not necessary to dispose an electrode along the etching groove as compared with a method in which an insulating film is applied to the element surface, an electrode is formed thereon, and the p-electrode 22 and the n-electrode 24 are electrically connected. Therefore, it is possible to avoid the problem that the elements constituting the insulating material are thermally diffused from the wiring breakage or from the insulating film to the n layer and the p layer to deteriorate the LED 1. The air bridge wiring 28 is used not only between the LEDs 1 but also for connection between the LEDs 1 and an electrode (not shown).

また、図４に示されるように、各ＬＥＤ１は互いに独立し、電気的に絶縁される必要がある。このため、各ＬＥＤ１はサファイア基板１０上で分離された構成となっている。サファイアはそれ自身絶縁体であるので、ＬＥＤ１をそれぞれ電気的に分離することができる。このように、サファイア基板１０をＬＥＤの電気的な分離を行うための抵抗体として使用することにより、容易かつ確実にＬＥＤの電気的な分離を行うことができる。 Further, as shown in FIG. 4, each LED 1 is independent from each other and needs to be electrically insulated. For this reason, each LED1 becomes the structure isolate | separated on the sapphire substrate 10. FIG. Since sapphire is itself an insulator, each LED 1 can be electrically isolated. As described above, by using the sapphire substrate 10 as a resistor for electrically separating the LEDs, it is possible to easily and reliably electrically separate the LEDs.

なお、発光素子としては、ｐｎ接合を有するＬＥＤの他、ＭＩＳとすることもできる。 In addition, as a light emitting element, it can also be set to MIS besides LED which has a pn junction.

図５には、発光装置の他の等価回路図が示されている。図において、２０個のＬＥＤ１が直列接続されて１つのＬＥＤアレイを形成しており、２つのＬＥＤアレイ（合計４０個のＬＥＤ）が電源に並列に接続されている。ＬＥＤ１の駆動電圧は５Ｖに設定されており、各ＬＥＤアレイの駆動電圧は１００Ｖとなっている。２つのＬＥＤアレイは図２と同様に互いに反対極性となるように電源に並列接続されており、電源の極性がいずれであっても必ずどちらかのＬＥＤアレイが発光することになる。 FIG. 5 shows another equivalent circuit diagram of the light emitting device. In the figure, 20 LEDs 1 are connected in series to form one LED array, and two LED arrays (total of 40 LEDs) are connected in parallel to the power source. The drive voltage of the LED 1 is set to 5V, and the drive voltage of each LED array is 100V. As in FIG. 2, the two LED arrays are connected in parallel to the power supply so as to have opposite polarities, and either LED array always emits light regardless of the polarity of the power supply.

図６には、二次元アレイが具体的に示されている。図２の等価回路図に対応するものである。図において、サファイア基板１０上に合計４０個のＬＥＤ１が形成されており、それぞれ２０個ずつ２組に分けられ、エアブリッジ配線２８により直列接続されて２つのＬＥＤアレイを形成している。より詳細には、各ＬＥＤ１は全て同形の正方形で同サイズであり、１つのＬＥＤアレイは上から６個、７個、７個とそれぞれ直線上に配置され、上から第１列目（６個）と第２列目（７個）は互いに逆向きに形成され、第２列目と第３列目も互いに逆向きに形成される。第１列目と第２列目、第２列目と第３列目は互いに離間して配置されている。これは、後述するように他方のＬＥＤアレイの列が交互に挿入されるためである。第１列目の右端のＬＥＤ１と第２列目の右端のＬＥＤ１とはエアブリッジ配線２８により接続される。第２列目の左端のＬＥＤ１と第３列目の左端のＬＥＤ１もエアブリッジ配線２８で接続されてジグザグ配列となる。第１列目の左端のＬＥＤ１は基板１０の左上部に形成された電極（パッド）３２にエアブリッジ配線２８で接続され、第３列目の右端のＬＥＤ１は基板１０の右下部に形成された電極（パッド）３２にエアブリッジ配線２８で接続される。２つの電極（パッド）３２もＬＥＤ１と同形の正方形である。他方のＬＥＤアレイは上述した一方のＬＥＤアレイの間隙に互い違いとなるように形成される。すなわち、他方のＬＥＤアレイは上から７個、７個、６個とそれぞれ直線上に配置され、上から第１列目は一方のＬＥＤアレイの第１列目と第２列目の間に形成され、第２列目は一方のＬＥＤアレイの第２列目と第３列目の間に形成され、第３列目は一方のＬＥＤアレイの第３列目の下に形成される。他方のＬＥＤアレイの第１列目と第２列目、及び第２列目と第３列目も互いに逆方向となるように形成され、第１列目の右端のＬＥＤ１は第２列目の右端のＬＥＤ１にエアブリッジ配線２８で接続され、第２列目の左端のＬＥＤ１は第３列の左端のＬＥＤ１にエアブリッジ配線２８で接続されてジグザグ状となる。他方のＬＥＤアレイの第１列目の左端のＬＥＤは基板１０の左上部に形成された電極３２にエアブリッジ配線２８で接続され、第３列目の右端のＬＥＤ１は基板１０の右下部に形成された電極３２にエアブリッジ配線２８で接続される。一方のＬＥＤアレイと他方のＬＥＤアレイの電極３２に対する極性は互いに逆である。発光装置（チップ）の全体形状は長方形である。電源が供給される２つの電極３２は、長方形の対角位置に離間して形成される点も着目されたい。 FIG. 6 specifically shows a two-dimensional array. This corresponds to the equivalent circuit diagram of FIG. In the figure, a total of 40 LEDs 1 are formed on the sapphire substrate 10, each being divided into two sets of 20 pieces and connected in series by an air bridge wiring 28 to form two LED arrays. More specifically, the LEDs 1 are all the same shape and are the same size, and one LED array is arranged on a straight line of 6, 7, and 7, respectively, from the top. ) And the second row (seven) are formed in opposite directions, and the second row and the third row are also formed in opposite directions. The first row and the second row, and the second row and the third row are arranged apart from each other. This is because the columns of the other LED array are alternately inserted as will be described later. The rightmost LED 1 in the first row and the rightmost LED 1 in the second row are connected by an air bridge wiring 28. The leftmost LED 1 in the second row and the leftmost LED 1 in the third row are also connected by the air bridge wiring 28 to form a zigzag arrangement. The leftmost LED 1 in the first row is connected to an electrode (pad) 32 formed in the upper left portion of the substrate 10 by an air bridge wiring 28, and the rightmost LED 1 in the third row is formed in the lower right portion of the substrate 10. An air bridge wiring 28 is connected to the electrode (pad) 32. The two electrodes (pads) 32 are also square with the same shape as the LED 1. The other LED array is formed to be staggered in the gap between the one LED array described above. That is, the other LED array is arranged on a straight line with 7, 7, and 6 from the top, and the first column from the top is formed between the first column and the second column of one LED array. The second column is formed between the second column and the third column of one LED array, and the third column is formed below the third column of the one LED array. The first column and the second column of the other LED array, and the second column and the third column are also formed in opposite directions, and the rightmost LED 1 of the first column is the second column. The leftmost LED 1 in the second row is connected to the rightmost LED 1 by the air bridge wiring 28, and the leftmost LED 1 in the second row is connected to the leftmost LED 1 by the air bridge wiring 28 to form a zigzag shape. The leftmost LED in the first column of the other LED array is connected to the electrode 32 formed in the upper left portion of the substrate 10 by the air bridge wiring 28, and the rightmost LED 1 in the third column is formed in the lower right portion of the substrate 10. The air bridge wiring 28 is connected to the formed electrode 32. The polarities of the one LED array and the other LED array with respect to the electrode 32 are opposite to each other. The overall shape of the light emitting device (chip) is rectangular. It should also be noted that the two electrodes 32 to which power is supplied are formed apart from each other in a rectangular diagonal position.

図７には、図６の回路図が示されている。それぞれのＬＥＤアレイはジグザグ状に屈曲しつつ直列接続され、２つのＬＥＤアレイはジグザグ状の各列が互いの列の間に形成される様子が明らかとなろう。このような配置とすることで、多数のＬＥＤ１を小さな基板１０上に配置することができる。また、４０個のＬＥＤ１に対して電極３２が２個でよいので、この点でも基板１０の使用効率を向上させることができる。また、各ＬＥＤ１を分離するためにＬＥＤ１を個別に形成する場合にはウエハをカットして分離する必要があるのに対し、本実施形態では各ＬＥＤ１の分離をエッチングで行うことができるので、ＬＥＤ１の間隔を狭くすることができる。これにより、サファイア基板１０の大きさをより小さくすることができる。ＬＥＤ１同士の分離は、フォトレジストや反応性イオンエッチング、ウエットエッチングを併用することでＬＥＤ１以外の領域を基板１０に達するまでエッチング除去することで達成される。各ＬＥＤアレイは交互に発光するので、発光効率を向上できるとともに放熱特性も向上させることができる。また、直列接続させるＬＥＤ１の数を変更すれば、全体としての駆動電圧も変更できる。また、ＬＥＤ１の面積を小さくすると、１つのＬＥＤ当たりの駆動電圧を高くすることもできる。ＬＥＤ１を２０個直列に接続した場合、商用電源（１００Ｖ、６０Ｈｚ）で駆動すると、およそ１５０ｍＷの発光出力を得ることができる。この場合の駆動電流としては２０ｍＡ程度である。 FIG. 7 shows a circuit diagram of FIG. It will be apparent that the respective LED arrays are connected in series while being bent in a zigzag manner, and two LED arrays are formed in a zigzag manner between each other. With such an arrangement, a large number of LEDs 1 can be arranged on the small substrate 10. Further, since only two electrodes 32 are required for 40 LEDs 1, the use efficiency of the substrate 10 can be improved in this respect. In addition, when the LEDs 1 are individually formed to separate the LEDs 1, it is necessary to cut and separate the wafer. In the present embodiment, the LEDs 1 can be separated by etching. The interval can be reduced. Thereby, the size of the sapphire substrate 10 can be further reduced. Separation of the LEDs 1 is achieved by etching away regions other than the LED 1 until the substrate 10 is reached by using a photoresist, reactive ion etching, and wet etching together. Since each LED array emits light alternately, it is possible to improve the light emission efficiency and heat dissipation characteristics. Further, if the number of LEDs 1 connected in series is changed, the driving voltage as a whole can also be changed. Moreover, if the area of LED1 is made small, the drive voltage per LED can also be made high. When 20 LEDs 1 are connected in series, a light output of about 150 mW can be obtained when driven by a commercial power supply (100 V, 60 Hz). In this case, the drive current is about 20 mA.

なお、図７から分かるように、２つのＬＥＤアレイをジグザグ状に交互に配列する場合、エアブリッジ配線２８に交叉部分３４が必然的に発生する。例えば、他方のＬＥＤアレイの第１列目と第２列目を接続する際に、一方のＬＥＤアレイの第１列目と第２列目を接続するための配線部分と交叉する。しかし、本実施形態のエアブリッジ配線２８は、上述したように基板１０に接着しておらず、基板１０から離れて空中を通過するので、交叉部分３４においてエアブリッジ配線２８同士が接触し、短絡することを容易に回避することができる。エアブリッジ配線２８を用いる利点の一つである。エアブリッジ配線２８は、例えば以下のようにして形成される。すなわち、全面に２μｍの厚さのフォトレジストを塗布し、エアブリッジ配線の形状に穴を開けた後にポストベークする。その上に、真空蒸着でＴｉを１０ｎｍ、Ａｕを１０ｎｍ、この順序で蒸着する。さらにその上の全面に２μｍ厚さでフォトレジストを再度塗布し、エアブリッジ配線を形成する部分のみに穴を開ける。次いで、ＴｉとＡｕを電極として電解液中でイオンプレーティング（メッキ）により電極全面に３〜５μｍの厚さのＡｕを付着させる。その後、試料をアセトンに浸し、超音波洗浄によりフォトレジストを溶解除去してエアブリッジ配線２８が完成する。 As can be seen from FIG. 7, when two LED arrays are alternately arranged in a zigzag shape, a crossing portion 34 is inevitably generated in the air bridge wiring 28. For example, when connecting the first column and the second column of the other LED array, it intersects with a wiring portion for connecting the first column and the second column of one LED array. However, since the air bridge wiring 28 of the present embodiment is not bonded to the substrate 10 as described above and passes through the air away from the substrate 10, the air bridge wirings 28 come into contact with each other at the crossover portion 34, and are short-circuited. This can be easily avoided. This is one of the advantages of using the air bridge wiring 28. The air bridge wiring 28 is formed as follows, for example. That is, a 2 μm-thick photoresist is applied to the entire surface, a hole is formed in the shape of the air bridge wiring, and post-baking is performed. On top of this, 10 nm of Ti and 10 nm of Au are deposited in this order by vacuum deposition. Further, a photoresist is again applied to the entire surface with a thickness of 2 μm, and a hole is made only in a portion where the air bridge wiring is formed. Next, Au having a thickness of 3 to 5 μm is attached to the entire surface of the electrode by ion plating (plating) in an electrolytic solution using Ti and Au as electrodes. Thereafter, the sample is immersed in acetone, and the photoresist is dissolved and removed by ultrasonic cleaning to complete the air bridge wiring 28.

このように、複数のＬＥＤ１を二次元アレイ状に配置することで、基板面積を有効に活用しつつ高駆動電圧、特に商用電源での駆動も可能となるが、二次元アレイのパターンとしてはこの他にも種々のパターンが可能である。一般に、二次元アレイパターンとしては、以下の条件を備えることが望ましい。
（１）各ＬＥＤに均一に電流を流し、均一な発光を得るためには各ＬＥＤの形状、電極位置が同一であることが望ましい。
（２）ウエハをカットしてチップにするためには、各ＬＥＤの辺は直線であることが望ましい。
（３）光取り出し効率を向上させるため、標準的なマウントを使用して周辺からの反射を利用するためにはＬＥＤは平面形状が正方形に近い形状が望ましい。
（４）２つの電極（ボンディングパット）の大きさは１００μｍ角程度で、互いに離れていることが望ましい。
（５）ウエハ面積の有効利用のため、配線、パッドの占める割合は小さい方が望ましい。もちろん、これらは必須ではなく、例えば各ＬＥＤの形状としては平面形状三角形を用いることも可能であろう。各ＬＥＤの形状が三角形であっても、これらを組み合わせることで全体形状を略正方形とすることができる。以下、二次元アレイパターンの例をいくつか示す。 Thus, by arranging a plurality of LEDs 1 in a two-dimensional array, it is possible to drive with a high drive voltage, particularly a commercial power supply, while effectively utilizing the substrate area. Various other patterns are possible. In general, the two-dimensional array pattern preferably has the following conditions.
(1) It is desirable that the shape and the electrode position of each LED be the same in order to pass a current uniformly to each LED and obtain uniform light emission.
(2) In order to cut the wafer into chips, it is desirable that the sides of each LED be straight.
(3) In order to improve the light extraction efficiency, in order to utilize reflection from the periphery using a standard mount, the LED preferably has a planar shape close to a square.
(4) The size of the two electrodes (bonding pads) is about 100 μm square, and it is desirable that they are separated from each other.
(5) In order to effectively use the wafer area, it is desirable that the proportion of wiring and pads is small. Of course, these are not essential, and for example, it is possible to use a planar shape triangle as the shape of each LED. Even if each LED has a triangular shape, the overall shape can be made substantially square by combining them. Hereinafter, some examples of the two-dimensional array pattern are shown.

図８には、合計６個のＬＥＤ１を二次元に配置した例が示されており、図９にはその回路図が示されている。図８の配置は、基本的には図６の配置と同様であり、合計６個のＬＥＤアレイは同数ずつ２組に分けられ、それぞれ直列接続された３個のＬＥＤから構成される。一方のＬＥＤアレイはジグザグ状に配列され、上から第１列目は１個のＬＥＤ１、第２列目は２個のＬＥＤ１が形成される。第１列目のＬＥＤと第２列目の右端のＬＥＤ１はエアブリッジ配線２８で直列接続され、第２列目の２個のＬＥＤ１もエアブリッジ配線２８で直列接続される。基板１０の左上部と左下部に電極（パッド）３２が形成され、第１列目のＬＥＤ１は左上部の電極３２にエアブリッジ配線で接続され、第２列目の左端のＬＥＤ１は左下部の電極３２に接続される。他方のＬＥＤアレイもジグザグ状に配列され、上から第１列目は２個のＬＥＤ１、第２列目は１個のＬＥＤ１が形成される。他方のＬＥＤアレイの第１列目は前記一方のＬＥＤアレイの第１列目と第２列目の間に形成され、他方のＬＥＤアレイの第２列目は前記一方のＬＥＤアレイの第２列目の下方に形成される。第１列目の右端のＬＥＤ１は第２列目のＬＥＤ１にエアブリッジ配線２８で直列接続され、第１列目の２個のＬＥＤ１同士もエアブリッジ配線２８で直列接続される。第１列目の左端のＬＥＤ１は左上部の電極３２にエアブリッジ配線２８で接続され、第２列目のＬＥＤ１は左下部の電極３２にエアブリッジ配線２８で接続される。図９から分かるように、この例でも２つのＬＥＤアレイは互いに並列に電極３２に接続され、かつ、互いに逆極性となるように接続される。したがって、交流電源を供給した場合、２つのＬＥＤアレイは交互に発光することになる。 FIG. 8 shows an example in which a total of six LEDs 1 are two-dimensionally arranged, and FIG. 9 shows a circuit diagram thereof. The arrangement of FIG. 8 is basically the same as the arrangement of FIG. 6, and the total of six LED arrays are divided into two sets of the same number, and are each composed of three LEDs connected in series. One LED array is arranged in a zigzag shape. From the top, one LED 1 is formed in the first row, and two LEDs 1 are formed in the second row. The LEDs in the first row and the rightmost LED 1 in the second row are connected in series by the air bridge wiring 28, and the two LEDs 1 in the second row are also connected in series by the air bridge wiring 28. Electrodes (pads) 32 are formed on the upper left and lower left of the substrate 10, the first row of LEDs 1 are connected to the upper left electrode 32 by air bridge wiring, and the leftmost LED 1 of the second row is connected to the lower left. Connected to the electrode 32. The other LED array is also arranged in a zigzag shape. From the top, two LEDs 1 are formed in the first row, and one LED 1 is formed in the second row. The first column of the other LED array is formed between the first column and the second column of the one LED array, and the second column of the other LED array is the second column of the one LED array. Formed below the eyes. The rightmost LED 1 in the first row is connected in series to the second row LED 1 via the air bridge wiring 28, and the two LEDs 1 in the first row are also connected in series via the air bridge wiring 28. The LED 1 at the left end of the first row is connected to the upper left electrode 32 by the air bridge wiring 28, and the LED 1 in the second row is connected to the lower left electrode 32 by the air bridge wiring 28. As can be seen from FIG. 9, also in this example, the two LED arrays are connected to the electrode 32 in parallel to each other and are connected to have opposite polarities. Therefore, when the AC power is supplied, the two LED arrays emit light alternately.

図１０には、合計１４個のＬＥＤを二次元配置した例が示されており、図１１にはその回路図が示されている。合計１４個のＬＥＤアレイは２組に分けられ、それぞれ直列接続された７個のＬＥＤから構成される。一方のＬＥＤアレイはジグザグ状に配列され、上から第１列目は３個のＬＥＤ１、第２列目は４個のＬＥＤ１が形成される。第１列目の左端のＬＥＤと第２列目の左端のＬＥＤ１はエアブリッジ配線２８で直列接続され、第１列目の３個のＬＥＤ同士、及び第２列目の４個のＬＥＤ１同士もエアブリッジ配線２８で直列接続される。基板１０の右上部と右下部に電極（パッド）３２が形成され、第１列目の右端のＬＥＤ１は右上部の電極３２にエアブリッジ配線で接続され、第２列目の右端のＬＥＤ１は右下部の電極３２に接続される。他方のＬＥＤアレイもジグザグ状に配列され、上から第１列目は４個のＬＥＤ１、第２列目は３個のＬＥＤ１が形成される。他方のＬＥＤアレイの第１列目は前記一方のＬＥＤアレイの第１列目と第２列目の間に形成され、他方のＬＥＤアレイの第２列目は前記一方のＬＥＤアレイの第２列目の下方に形成される。第１列目の左端のＬＥＤ１は第２列目の左端のＬＥＤ１にエアブリッジ配線２８で直列接続される。第１列目の４個のＬＥＤ１同士、及び第２列目の３個のＬＥＤ１同士も直列接続される。第１列目の右端のＬＥＤ１は右上部の電極３２にエアブリッジ配線２８で接続され、第２列目の右端のＬＥＤ１は右下部の電極３２にエアブリッジ配線２８で接続される。図１１から分かるように、この例でも２つのＬＥＤアレイは互いに並列に電極３２に接続され、かつ、互いに逆極性となるように接続される。したがって、交流電源を供給した場合、２つのＬＥＤアレイは交互に発光することになる。 FIG. 10 shows an example in which a total of 14 LEDs are two-dimensionally arranged, and FIG. 11 shows a circuit diagram thereof. A total of 14 LED arrays are divided into 2 sets, each consisting of 7 LEDs connected in series. One LED array is arranged in a zigzag shape, and from the top, three LEDs 1 are formed in the first row, and four LEDs 1 are formed in the second row. The leftmost LED in the first row and the leftmost LED1 in the second row are connected in series by an air bridge wiring 28, and the three LEDs in the first row and the four LEDs 1 in the second row are also connected. The air bridge wiring 28 is connected in series. Electrodes (pads) 32 are formed on the upper right portion and lower right portion of the substrate 10, the rightmost LED 1 in the first row is connected to the upper right electrode 32 by an air bridge wiring, and the rightmost LED 1 in the second row is on the right Connected to the lower electrode 32. The other LED array is also arranged in a zigzag shape. From the top, four LEDs 1 are formed in the first row, and three LEDs 1 are formed in the second row. The first column of the other LED array is formed between the first column and the second column of the one LED array, and the second column of the other LED array is the second column of the one LED array. Formed below the eyes. The leftmost LED 1 in the first row is connected in series to the leftmost LED 1 in the second row by an air bridge wiring 28. The four LEDs 1 in the first row and the three LEDs 1 in the second row are also connected in series. The rightmost LED 1 in the first row is connected to the upper right electrode 32 by an air bridge wiring 28, and the rightmost LED 1 in the second row is connected to the lower right electrode 32 by an air bridge wiring 28. As can be seen from FIG. 11, also in this example, the two LED arrays are connected to the electrode 32 in parallel with each other and connected to have opposite polarities. Therefore, when the AC power is supplied, the two LED arrays emit light alternately.

図６、図８、図１０の二次元パターンに共通する特徴としては、各ＬＥＤ１が略正方形の同形、同サイズであること、２つの電極（パッド）も略正方形であり、隣接形成されていない（離間形成されている）こと、２つのＬＥＤアレイの組み合わせであること、２つのＬＥＤアレイは屈曲しつつチップ上に互いに交錯するように形成されること、２つのＬＥＤアレイは互いに逆極性となるように電極に接続されること、等である。 The common features of the two-dimensional patterns of FIGS. 6, 8, and 10 are that each LED 1 has a substantially square shape and size, and the two electrodes (pads) are also substantially square and are not formed adjacent to each other. It is a combination of two LED arrays (separately formed), the two LED arrays are bent and formed to cross each other on the chip, and the two LED arrays have opposite polarities Connected to the electrode, and so on.

図１２には、平面形状が三角形のＬＥＤを二次元配列した場合の例が示されており、図１３にはその回路図が示されている。図１２において、合計６個のＬＥＤ１ａ、１ｂ、１ｃ、１ｄ、１ｅ、１ｆがその平面形状が三角形状となるように形成されている。ＬＥＤ１ａとＬＥＤ１ｅが三角形の一辺で対向して２つで略正方形となるように配置され、ＬＥＤ１ｂと１ｆが対向して２つで略正方形となるように配置される。また、ＬＥＤ１ｄと電極３２が対向して接続し、ＬＥＤ１ｃと電極３２が対向して接続する。２つの電極３２もＬＥＤと同様に平面形状が三角形状であり、同様に略正方形となるように配置される。ＬＥＤ同士の対向する辺はｎ電極２４を構成し、すなわち、対向する２つのＬＥＤはｎ電極２４を共有する。ＬＥＤと電極３２もｎ電極接続である。この配置も、上述した例と同様に合計６個のＬＥＤは２組に分けられる。一方のＬＥＤアレイは、ＬＥＤ１ａ、ＬＥＤ１ｂ、ＬＥＤ１ｃからなるアレイであり、ＬＥＤ１ａのｐ電極２２は電極３２にエアブリッジ配線２８で接続され、そのｎ電極２４はＬＥＤ１ｂのｐ電極２２とエアブリッジ配線２８で接続される。ＬＥＤ１ｂのｎ電極２４はＬＥＤ１ｃのｐ電極２２とエアブリッジ配線２８で接続される。ＬＥＤ１ｃのｎ電極２４は電極３２に接続される。他方のＬＥＤアレイは、ＬＥＤ１ｄ、ＬＥＤ１ｅ、ＬＥＤ１ｆから構成され、電極３２とＬＥＤ１ｆのｐ電極２２はエアブリッジ配線２８で接続され、ＬＥＤ１ｆのｎ電極２４はＬＥＤ１ｅのｐ電極２２とエアブリッジ配線２８で接続され、ＬＥＤ１ｅのｎ電極２４とＬＥＤ１ｄのｐ電極２２はエアブリッジ配線２８で接続され、ＬＥＤ１ｄのｎ電極２４は電極３２に接続される。 FIG. 12 shows an example in which LEDs having a triangular planar shape are two-dimensionally arranged, and FIG. 13 shows a circuit diagram thereof. In FIG. 12, a total of six LEDs 1a, 1b, 1c, 1d, 1e, and 1f are formed so that the planar shape thereof is a triangular shape. The LED 1a and the LED 1e are arranged so as to be substantially square with two facing one side of the triangle, and the LEDs 1b and 1f are arranged so as to be substantially square with two facing each other. Further, the LED 1d and the electrode 32 are connected to face each other, and the LED 1c and the electrode 32 are connected to face each other. The two electrodes 32 have a triangular shape in the same manner as the LED, and are arranged so as to be substantially square. The opposing sides of the LEDs constitute an n-electrode 24, that is, the two opposing LEDs share the n-electrode 24. The LED and the electrode 32 are also n-electrode connected. Also in this arrangement, a total of six LEDs are divided into two sets as in the example described above. One LED array is an array composed of LED 1a, LED 1b, and LED 1c. The p electrode 22 of the LED 1a is connected to the electrode 32 by an air bridge wiring 28, and the n electrode 24 is connected to the p electrode 22 of the LED 1b and the air bridge wiring 28. Connected. The n-electrode 24 of the LED 1 b is connected to the p-electrode 22 of the LED 1 c by an air bridge wiring 28. The n electrode 24 of the LED 1 c is connected to the electrode 32. The other LED array is composed of LED 1d, LED 1e, and LED 1f. The electrode 32 and the p electrode 22 of the LED 1f are connected by an air bridge wiring 28, and the n electrode 24 of the LED 1f is connected by a p electrode 22 of the LED 1e and an air bridge wiring 28. Then, the n electrode 24 of the LED 1 e and the p electrode 22 of the LED 1 d are connected by an air bridge wiring 28, and the n electrode 24 of the LED 1 d is connected to the electrode 32.

図１３において、一方のＬＥＤアレイを構成するＬＥＤ１ａと他方のＬＥＤアレイを構成するＬＥＤ１ｅのｎ電極が接続されており、一方のＬＥＤアレイを構成するＬＥＤ１ｂと他方のＬＥＤアレイを構成するＬＥＤ１ｆのｎ電極が接続されている点にも着目されたい。２組のＬＥＤアレイのいくつかのｎ電極を共有することで、回路配線を削減することができる。また、この例においても、２つのＬＥＤアレイは並列に電極３２に接続され、かつ、互いに逆極性となるように接続される。また、各ＬＥＤは同形、同サイズであり、各ＬＥＤを一つの辺で対向させるとともに電極３２も三角形状とすることでＬＥＤ及び電極を高密度に形成して必要な基板面積を小さくすることができる。 In FIG. 13, the LED 1a constituting one LED array and the n electrode of the LED 1e constituting the other LED array are connected, and the LED 1b constituting the one LED array and the n electrode of the LED 1f constituting the other LED array. Note also that is connected. By sharing some n-electrodes of the two sets of LED arrays, circuit wiring can be reduced. Also in this example, the two LED arrays are connected in parallel to the electrode 32 and are connected to have opposite polarities. In addition, each LED has the same shape and size, and each LED is opposed to one side and the electrode 32 is also formed in a triangular shape, so that the LEDs and electrodes can be formed at a high density to reduce the necessary substrate area. it can.

図１４には、平面形状が三角形のＬＥＤを二次元配列した他の例が示されており、図１５にはその回路図が示されている。この例では、合計１６個のＬＥＤ１ａ〜１ｒが二次元形成されている。ＬＥＤ１ａと１ｊ、１ｂと１ｋ、１ｃと１ｍ、１ｄと１ｎ、１ｅと１ｐ、１ｆと１ｑ、１ｇと１ｒがそれぞれ三角形の一つの辺で対向する。対向する辺にはｎ電極２４が共通形成されている。また、ＬＥＤ１ｉと電極３２が対向し、ＬＥＤ１ｈと電極３２が対向する。一方のＬＥＤアレイはＬＥＤ１ａ、１ｂ、１ｃ、１ｄ、１ｅ、１ｆ、１ｇ、１ｈから構成され、他方のＬＥＤアレイはＬＥＤ１ｒ、１ｑ、１ｐ、１ｎ、１ｍ、１ｋ、１ｊ、１ｉから構成される。ＬＥＤ１ｂのｎ電極２４はエアブリッジ配線２８によりＬＥＤ１ｃのｐ電極２２に接続され、ＬＥＤ１ｅのｎ電極２４もエアブリッジ配線２８によりＬＥＤ１ｆのｐ電極２２に接続される。また、ＬＥＤ１ｑのｎ電極２４もエアブリッジ配線２８によりＬＥＤ１ｐのｐ電極２２に接続され、ＬＥＤ１ｍのｎ電極２４もエアブリッジ配線２８によりＬＥＤ１ｋのｐ電極２２に接続される。図１４においても、図１２と同様に交叉部分が生じるが、エアブリッジ配線２８により短絡を回避できる。また、この例においても２組のＬＥＤアレイのいくつかのｎ電極２４を共有構造とすることで必要な配線を削減している。また、この例においても２つのＬＥＤアレイは並列で互いに逆極性で電極３２に接続されており、交流駆動が可能である。図１２においては合計６個のＬＥＤの場合、図１４においては合計１６個のＬＥＤの場合について示したが、他の個数のＬＥＤでも同様に二次元配列できる。本願出願人は、３８個のＬＥＤを二次元配列した発光装置も作成している。 FIG. 14 shows another example in which LEDs having a triangular planar shape are two-dimensionally arranged, and FIG. 15 shows a circuit diagram thereof. In this example, a total of 16 LEDs 1a to 1r are two-dimensionally formed. LEDs 1a and 1j, 1b and 1k, 1c and 1m, 1d and 1n, 1e and 1p, 1f and 1q, 1g and 1r face each other on one side of the triangle. An n-electrode 24 is commonly formed on the opposite sides. Further, the LED 1i and the electrode 32 face each other, and the LED 1h and the electrode 32 face each other. One LED array is composed of LEDs 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, and the other LED array is composed of LEDs 1r, 1q, 1p, 1n, 1m, 1k, 1j, 1i. The n electrode 24 of the LED 1b is connected to the p electrode 22 of the LED 1c by the air bridge wiring 28, and the n electrode 24 of the LED 1e is also connected to the p electrode 22 of the LED 1f by the air bridge wiring 28. The n electrode 24 of the LED 1q is also connected to the p electrode 22 of the LED 1p by the air bridge wiring 28, and the n electrode 24 of the LED 1m is also connected to the p electrode 22 of the LED 1k by the air bridge wiring 28. In FIG. 14, a crossover portion is generated as in FIG. 12, but a short circuit can be avoided by the air bridge wiring 28. Also in this example, necessary wiring is reduced by making some n electrodes 24 of the two sets of LED arrays have a common structure. Also in this example, the two LED arrays are connected in parallel to the electrodes 32 with opposite polarities, and can be driven by alternating current. Although FIG. 12 shows a case of a total of 6 LEDs and FIG. 14 shows a case of a total of 16 LEDs, other numbers of LEDs can be similarly two-dimensionally arranged. The applicant of the present application has also created a light emitting device in which 38 LEDs are two-dimensionally arranged.

以上、交流駆動の場合について説明したが、直流駆動も可能であることは言うまでもない。この場合、ＬＥＤアレイを互いに逆極性となるように電極に接続するのではなく、直流電源の極性の向きに合わせてＬＥＤアレイを順方向に接続すればよい。複数のＬＥＤを直列接続することで、高電圧駆動が可能である。以下、直流駆動の場合についても説明する。 Although the case of AC driving has been described above, it goes without saying that DC driving is also possible. In this case, the LED array may be connected in the forward direction according to the polarity direction of the DC power supply, instead of connecting the LED array to the electrodes so as to have opposite polarities. High voltage driving is possible by connecting a plurality of LEDs in series. Hereinafter, the case of direct current drive will also be described.

図１６には、２個のＬＥＤを直列接続した例が示されており、図１７にはその回路図が示されている。各ＬＥＤ１は平面形状が矩形状であり、２個のＬＥＤ間はエアブリッジ配線２８で接続される。電極３２は各ＬＥＤ１の近傍に形成されており、電極３２とＬＥＤ１とで長方形の領域を形成する。すなわち、電極３２は長方形領域の一部を占有し、長方形領域の他の領域にＬＥＤ１が形成されている。 FIG. 16 shows an example in which two LEDs are connected in series, and FIG. 17 shows a circuit diagram thereof. Each LED 1 has a rectangular planar shape, and the two LEDs are connected by an air bridge wiring 28. The electrode 32 is formed in the vicinity of each LED 1, and the electrode 32 and the LED 1 form a rectangular region. That is, the electrode 32 occupies a part of the rectangular area, and the LED 1 is formed in another area of the rectangular area.

図１８には、合計４個のＬＥＤを二次元配列した例が示されており、図１９にはその回路図が示されている。図１６のＬＥＤ１を２個に分割し、それぞれを並列に接続したものである。２個のＬＥＤからなるＬＥＤアレイを２組並列に順方向接続したと云うこともできる。ＬＥＤ１ａと１ｂで一つのＬＥＤアレイを構成し、ＬＥＤ１ｃと１ｄでもう一つのＬＥＤアレイを構成する。ＬＥＤ１ａとＬＥＤ１ｃはｐ電極２２及びｎ電極２４を共有し、ＬＥＤ１ｂとＬＥＤ１ｄもｐ電極２２及びｎ電極２４を共有する。この構成によれば、図１６に比べて電流が均一化する効果がある。 FIG. 18 shows an example in which a total of four LEDs are two-dimensionally arranged, and FIG. 19 shows a circuit diagram thereof. LED1 of FIG. 16 is divided | segmented into two, and each is connected in parallel. It can also be said that two sets of LED arrays composed of two LEDs are connected in a forward direction in parallel. The LEDs 1a and 1b constitute one LED array, and the LEDs 1c and 1d constitute another LED array. LED 1a and LED 1c share the p electrode 22 and n electrode 24, and LED 1b and LED 1d also share the p electrode 22 and n electrode 24. According to this configuration, there is an effect that the current becomes uniform as compared with FIG.

図２０は、合計３個のＬＥＤを二次元配列した例が示されており、図２１にはその回路図が示されている。ＬＥＤ１ａ、１ｂ、１ｃは同形ではなく、ＬＥＤ１ａの一部に電極３２が形成されている。ＬＥＤ１ａのｎ電極２４とＬＥＤ１ｂのｐ電極はＬＥＤ１ｂの上を跨ぐエアブリッジ配線２８で接続される。各ＬＥＤの形状及び配置を工夫することで、３個のＬＥＤであっても発光装置（チップ）全体の外観形状を略正方形とすることができる。 FIG. 20 shows an example in which a total of three LEDs are two-dimensionally arranged, and FIG. 21 shows a circuit diagram thereof. The LEDs 1a, 1b and 1c are not the same shape, and an electrode 32 is formed on a part of the LED 1a. The n electrode 24 of the LED 1a and the p electrode of the LED 1b are connected by an air bridge wiring 28 that straddles the LED 1b. By devising the shape and arrangement of each LED, the appearance of the entire light emitting device (chip) can be substantially square even with three LEDs.

図２２には、合計６個のＬＥＤを二次元配列した例が示されており、図２３にはその回路図が示されている。各ＬＥＤ１ａ〜１ｆは同形、同サイズである。ＬＥＤ１ａ〜１ｆは直列接続される。ＬＥＤ１ａ〜１ｃは直線上に配置され、ＬＥＤ１ｄ〜１ｆは他の直線上に配置される。ＬＥＤ１ｃとＬＥＤ１ｄはエアブリッジ配線２８で接続される。この例においても、チップの全体形状を略正方形とすることができる。 FIG. 22 shows an example in which a total of six LEDs are two-dimensionally arranged, and FIG. 23 shows a circuit diagram thereof. Each LED 1a-1f is the same shape and the same size. The LEDs 1a to 1f are connected in series. The LEDs 1a to 1c are arranged on a straight line, and the LEDs 1d to 1f are arranged on another straight line. The LED 1c and the LED 1d are connected by an air bridge wiring 28. Also in this example, the overall shape of the chip can be made substantially square.

図２４には、合計５個のＬＥＤを二次元配列した例が示されており、図２５にはその回路図が示されている。ＬＥＤ１ａ〜１ｅは同形（長方形）、同サイズである。この例においても、全体形状を略正方形とすることができる。 FIG. 24 shows an example in which a total of five LEDs are two-dimensionally arranged, and FIG. 25 shows a circuit diagram thereof. The LEDs 1a to 1e have the same shape (rectangular shape) and the same size. Also in this example, the overall shape can be made substantially square.

以上、本発明の実施形態について説明したが、本発明はこれに限定されるものではなく種々の変更が可能である。特に、複数の発光素子（ＬＥＤ等）を二次元配置する場合のパターンは上述したパターン以外にも可能である。この場合、隣接する発光素子間で電極を共有して配線を少なくすること、全体形状を正方形あるいは長方形とすること、複数組の発光素子アレイを電極に並列接続すること、交流駆動の場合に複数組の発光素子アレイを互い逆極性とすること、複数組の発光素子アレイをそれぞれジグザグ状に屈曲させて組み合わせること、等が好適である。 As mentioned above, although embodiment of this invention was described, this invention is not limited to this, A various change is possible. In particular, the pattern in the case where a plurality of light emitting elements (LEDs, etc.) are two-dimensionally arranged is possible in addition to the patterns described above. In this case, the electrodes are shared between adjacent light emitting elements to reduce wiring, the overall shape is square or rectangular, a plurality of sets of light emitting element arrays are connected in parallel to the electrodes, and plural in the case of AC drive. It is preferable that the sets of light emitting element arrays have opposite polarities, the plurality of sets of light emitting element arrays are combined in a zigzag manner, and the like.

図２６〜図３１には、これらの変更例のいくつかが例示されている。図２６は交流駆動の場合の二次元配置であり、合計４０個のＬＥＤが配置されている。図２７はその回路図である。図６と異なる点は、２組のＬＥＤアレイのいくつかがｎ電極２４を共有する点である（図５参照）。例えば、一方のＬＥＤアレイの第１列の右端から２番目に位置するＬＥＤ（図中αで示す）のｎ電極２４は、他方のＬＥＤアレイの第１列の右端に位置するＬＥＤ（図中βで示す）のｎ電極２４と共有されている。なお、ＬＥＤアレイの端部（図中γ部分）におけるエアブリッジ配線２８は、交叉させることなく共通形成されている。 26 to 31 illustrate some of these modifications. FIG. 26 shows a two-dimensional arrangement in the case of AC driving, in which a total of 40 LEDs are arranged. FIG. 27 is a circuit diagram thereof. The difference from FIG. 6 is that some of the two sets of LED arrays share the n-electrode 24 (see FIG. 5). For example, the n electrode 24 of the LED located second from the right end of the first column of one LED array (indicated by α in the figure) is the LED (β in the figure) located at the right end of the first column of the other LED array. And the n-electrode 24 shown in FIG. In addition, the air bridge wiring 28 in the edge part (gamma part in a figure) of a LED array is formed in common, without making it cross.

図２８は、交流駆動の場合の二次元配置であり、合計１４個のＬＥＤが配置されている。図２９はその回路図である。図１０と異なる点は、２組のＬＥＤアレイのいくつかがｎ電極２４を共有する点である。例えば、一方のＬＥＤアレイの第１列の左端のＬＥＤ（図中αで示す）のｎ電極２４は、他方のＬＥＤアレイの第１列の右端から２番目に位置するＬＥＤ（図中βで示す）のｎ電極２４と共有されている。また、端部（図中γ部分）におけるエアブリッジ配線２８は共通形成されている。 FIG. 28 shows a two-dimensional arrangement in the case of AC driving, in which a total of 14 LEDs are arranged. FIG. 29 is a circuit diagram thereof. A difference from FIG. 10 is that some of the two sets of LED arrays share the n-electrode 24. For example, the n electrode 24 of the leftmost LED (indicated by α in the figure) of the first column of one LED array is the second LED from the right end of the first column of the other LED array (indicated by β in the figure). ) N electrode 24. In addition, the air bridge wiring 28 at the end (γ portion in the figure) is formed in common.

図３０は、交流駆動の場合の二次元配置であり、合計６個のＬＥＤが配置されている。図３１はその回路図である。この例においても、端部（γ部）のエアブリッジ配線２８が共通形成されている。この構成も、一方のＬＥＤアレイにおけるｎ電極２４と他方のＬＥＤアレイにおけるｎ電極２４が共有されていると云うことができる。 FIG. 30 shows a two-dimensional arrangement in the case of AC driving, in which a total of six LEDs are arranged. FIG. 31 is a circuit diagram thereof. Also in this example, the air bridge wiring 28 at the end portion (γ portion) is formed in common. In this configuration as well, it can be said that the n electrode 24 in one LED array and the n electrode 24 in the other LED array are shared.

発光素子（ＬＥＤ）の基本構成図である。It is a basic lineblock diagram of a light emitting element (LED). 発光装置の等価回路図である。It is an equivalent circuit diagram of a light-emitting device. ２個のＬＥＤの平面図である。It is a top view of two LED. 図３のＩＶ−ＩＶ断面図である。It is IV-IV sectional drawing of FIG. 発光装置の他の等価回路図である。It is another equivalent circuit schematic of a light-emitting device. ４０個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged 40 LED two-dimensionally. 図６の回路図である。FIG. 7 is a circuit diagram of FIG. 6. ６個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged six LED two-dimensionally. 図８の回路図である。FIG. 9 is a circuit diagram of FIG. 8. １４個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged 14 LED two-dimensionally. 図１０の回路図である。FIG. 11 is a circuit diagram of FIG. 10. ６個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged six LED two-dimensionally. 図１２の回路図である。FIG. 13 is a circuit diagram of FIG. 12. １６個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged 16 LED two-dimensionally. 図１４の回路図である。FIG. 15 is a circuit diagram of FIG. 14. ２個のＬＥＤを配列した説明図である。It is explanatory drawing which arranged two LED. 図１６の回路図である。FIG. 17 is a circuit diagram of FIG. 16. ４個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged four LED two-dimensionally. 図１８の回路図である。FIG. 19 is a circuit diagram of FIG. 18. ３個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged three LED in two dimensions. 図２０の回路図である。FIG. 21 is a circuit diagram of FIG. 20. ６個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged six LED two-dimensionally. 図２２の回路図である。FIG. 23 is a circuit diagram of FIG. 22. ５個のＬＥＤを二次元配列した説明図である。It is explanatory drawing which arranged two LED two-dimensionally. 図２４の回路図である。FIG. 25 is a circuit diagram of FIG. 24. 他の二次元配置説明図である。It is another two-dimensional arrangement explanatory drawing. 図２６の回路図である。FIG. 27 is a circuit diagram of FIG. 26. 他の二次元配置説明図である。It is another two-dimensional arrangement explanatory drawing. 図２８の回路図である。FIG. 29 is a circuit diagram of FIG. 28. 他の二次元配置説明図である。It is another two-dimensional arrangement explanatory drawing. 図３０の回路図である。FIG. 31 is a circuit diagram of FIG. 30.

Explanation of symbols

１０基板（ウエハ）
１２ｕ−ＧａＮ層
１４ｎ型ＧａＮ層
１６ＩｎＧａＮ発光層
１８ＡｌＧａＮ層
２０ｐ−ＧａＮ層
２２ｐ−電極
２４ｎ−電極 10 Substrate (wafer)
12 u-GaN layer 14 n-type GaN layer 16 InGaN light emitting layer 18 AlGaN layer 20 p-GaN layer 22 p-electrode 24 n-electrode

Claims

A light-emitting device in which a plurality of GaN-based light-emitting diode elements are formed on an insulating substrate,
The plurality of light emitting diode elements are arranged in a matrix on the insulating substrate,
The plurality of light emitting diode elements are connected in parallel to two AC power supply electrodes so as to be electrically divided into a first set and a second set as opposite polarities,
The first set of light emitting diode elements includes a first light emitting diode element row and a second light emitting diode element row, and the second set of light emitting diode elements is a third light emitting diode element row. A fourth row of light emitting diode elements, wherein the third light emitting diode element row is disposed between the first light emitting diode element row and the second light emitting diode element row,
An electrode of a light emitting diode element at one end of the matrix array of the first light emitting diode element row, and a light emitting diode at an end of the first light emitting diode element row on the one side side The electrode of the element, the electrode of the light emitting diode element at the end of the one side of the column of the third light emitting diode element, and the light emitting diode of the edge of the side of the fourth light emitting diode element is shared and the device electrodes are electrically connected, and the light emitting device wherein a directly to two AC power supply electrode, wherein no Tei connected.

The apparatus of claim 1.
The electrode of the light emitting diode element at the end of the column of the first light emitting diode element and the electrode of the light emitting diode element at the end of the column of the fourth light emitting diode element have the same polarity, and the second light emission A light emitting device, wherein the electrode of the light emitting diode element at the end of the row of diode elements and the electrode of the light emitting diode element at the end of the third light emitting diode element have the same polarity.

The apparatus of claim 1.
The electrode of the light emitting diode element at the end of the column of the first light emitting diode element and the electrode of the light emitting diode element at the end of the column of the second light emitting diode element have opposite polarities, and the third light emission A light emitting device characterized in that the electrode of the light emitting diode element at the end of the row of diode elements and the electrode of the light emitting diode element at the end of the fourth light emitting diode element have opposite polarities.

The apparatus of claim 1.
2. The light emitting device according to claim 2, wherein the two AC power supply electrodes are arranged at opposite ends of the matrix-shaped diagonal line.

The apparatus of claim 1.
The two AC power supply electrodes are disposed at both ends of one side of the matrix-shaped end portion.

The apparatus of claim 1.
The two AC power supply electrodes and the plurality of light emitting diode elements each have a planar shape substantially the same shape and the same size.

The apparatus of claim 1.
The two AC power supply electrodes and the plurality of light emitting diode elements have a substantially square planar shape and are arranged in a matrix.

The apparatus of claim 1.
All the light emitting diode elements which comprise the said 1st group are connected in series between the electrodes for two alternating current power supplies, The light emitting device characterized by the above-mentioned.

The apparatus of claim 8.
All the light emitting diode elements which comprise the 2nd set are connected in series between two electrodes for alternating current power supplies, The light-emitting device characterized by the above-mentioned.

The apparatus of claim 1.
A light-emitting diode in which the negative electrode of any one of the light-emitting diode elements constituting the first column is adjacent to the light-emitting diode element among the light-emitting diode elements constituting the third column A light-emitting device that is shared with and electrically connected to a negative electrode of an element.

The apparatus of claim 1.
The first electrode of the light emitting diode element constituting the second column and the first electrode of the light emitting diode element constituting the second column at the end on one side of the arrangement of the light emitting diode elements constituting the first column on the matrix. A second electrode of the light emitting diode element at the end on the side, a third electrode of the light emitting diode element at the end on the one side of the light emitting diode elements constituting the third row, and the first electrode The fourth electrode of the light emitting diode element at the end of the one side of the light emitting diode elements constituting the four columns is shared and electrically connected, and the first electrode and the fourth electrode Are the same polarity, the second electrode and the third electrode have the same polarity, and the polarities of the first electrode, the fourth electrode, the second electrode, and the third electrode Are different from each other.

The apparatus of claim 11.
The first set of light emitting diode elements further includes a fifth row of light emitting diode elements;
The second set of light emitting diode elements further includes a column of sixth light emitting diode elements;
The fourth light emitting diode element row is disposed between the second light emitting diode element row and the fifth light emitting diode element row,
The fifth light emitting diode element row is disposed between the fourth light emitting diode element row and the sixth light emitting diode element row,
5th electrode of the light emitting diode element of the edge | side part opposite to 1 side of arrangement | positioning on the said matrix of the light emitting diode element which comprises the said 2nd row | line | column, and the light emitting diode which comprises the said 4th row | line | column The sixth electrode of the light emitting diode element at the end on the opposite side of the element and the seventh light emitting diode element at the end on the opposite side of the light emitting diode elements constituting the fifth column. And the eighth electrode of the light emitting diode element at the end on the opposite side of the light emitting diode elements constituting the sixth column are respectively shared and electrically connected, and the 2 The AC power supply electrodes are not directly connected, the fifth electrode and the eighth electrode have the same polarity, and the sixth electrode and the seventh electrode have the same polarity And the fifth electrode and the eighth electrode and the front Emitting device the polarity of the sixth electrode and the seventh electrode is characterized different.

The apparatus of claim 12.
The light emitting device according to claim 10, wherein the row of elements of each light emitting diode is individually arranged on a straight line on the insulating substrate.

The apparatus of claim 11.
The light emitting device, wherein the first electrode, the second electrode, the third electrode, and the fourth electrode are shared and electrically connected by an air bridge wiring.

The apparatus of claim 12.
The first electrode, the second electrode, the third electrode, and the fourth electrode are shared and electrically connected by a first air bridge wiring;
The light emission characterized in that the fifth electrode, the sixth electrode, the seventh electrode, and the eighth electrode are shared and electrically connected by a second air bridge wiring. apparatus.

The apparatus of claim 15.
A light emitting device characterized in that a first air bridge wiring and a second air bridge wiring are arranged at both ends of the insulating substrate.

The apparatus of claim 1.
The plurality of light emitting diode elements have a triangular plane shape,
A light emitting diode element adjacent to one of the light emitting diode elements of the light emitting diode elements constituting the first set and the light emitting diode element of the light emitting diode elements constituting the second set is: A light-emitting device characterized by being arranged so that a planar shape is substantially square by facing one side of a triangle and sharing a negative electrode on the facing side.

The apparatus according to any one of claims 1 to 17,
The light emitting device, wherein the first set of light emitting diode elements and the second set of light emitting diode elements are alternately arranged in a zigzag shape.

The device according to any one of claims 1 to 18,
The light-emitting device, wherein the plurality of light-emitting diode elements are integrally formed.