JP4295525B2

JP4295525B2 - Light emitting element storage package and light emitting device

Info

Publication number: JP4295525B2
Application number: JP2003044397A
Authority: JP
Inventors: 陽介森山; 明彦舟橋; 敏幸千歳
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2003-01-28
Filing date: 2003-02-21
Publication date: 2009-07-15
Anticipated expiration: 2023-02-21
Also published as: JP2004288657A

Description

【０００１】
【発明の属する技術分野】
本発明は、発光ダイオード等の発光素子を用いた表示装置等に用いられる、発光素子を収納するための発光素子収納用パッケージおよび発光装置に関する。
【０００２】
【従来の技術】
従来、発光ダイオード等の発光素子を収納するための発光素子収納用パッケージ（以下、パッケージともいう）として、セラミック製のパッケージが用いられており、その一例を図９に示す（例えば、下記の特許文献１参照）。同図に示すように、従来のパッケージは、複数のセラミック層が積層されて成るとともに上面に凹部14が形成され、その底面に発光素子13を搭載するための導体層から成る搭載部導体層12（以下、搭載部ともいう）が設けられた直方体状の絶縁基体11と、絶縁基体11の搭載部12およびその周辺から絶縁基体11の下面に導出された一対のメタライズ配線導体から成る配線層15とから主に構成されている。
【０００３】
そして、一方の配線層15の一端が電気的に接続された搭載部12上に発光素子13を導電性接着剤、はんだ等を介して載置固定するとともに、発光素子13の電極と他方の配線層15とをボンディングワイヤ16を介して電気的に接続し、しかる後、絶縁基体11の凹部14内に透明樹脂を充填して発光素子13を封止することによって、発光装置が作製される。
【０００４】
なお、この発光装置は多数個を互いに隣接するように配列されて使用されることから、上記セラミック製のパッケージにおいては、搭載部12に搭載された発光素子13が発する光が絶縁基体11を透過して、隣接する発光装置同士の光が混色するのを有効に防止するために、絶縁基体11にセラミックスから成るものを用いている。また、凹部14の内面で発光素子13の光を反射させてパッケージの上方に光を放射させるために、凹部14の内面にニッケル（Ｎｉ）めっき層や金（Ａｕ）めっき層を表面に有するメタライズ層からなる金属層17を被着させていることもある。
【０００５】
【特許文献１】
特開2002−232017号公報
【０００６】
【発明が解決しようとする課題】
しかしながら、上記従来のパッケージにおいては、絶縁基体11の搭載部12および配線層15と、凹部14の内面の金属層17との間には、電気的短絡を防止するためにセラミックスを露出させた露出領域を形成しているが、絶縁基体11の厚みを厚くすると、発光素子13の光を絶縁基体11が透過して外部に漏れることがなく、発光素子13の光をパッケージの外部に効率良く放射することができるが、パッケージが大型化するという問題点を有していた。一方、絶縁基体11を薄くした場合、パッケージは小型化されるが、発光素子13の光の一部は絶縁基体11を透過して外部へ漏れ出てしまい、発光装置の発光効率が低下するととともに、隣接する発光装置同士の光が混色するという問題点もあった。
【０００７】
また、搭載部12を凹部14の底面の全面に形成し、配線層15を凹部14の内面（内側面）や絶縁基体11上面の凹部14の周囲に形成した場合、ボンディングワイヤ16の接続が難しくなったり、発光装置自体が大型化するという問題点を有していた。
【０００８】
従って、本発明は上記従来の問題点に鑑みて完成されたものであり、その目的は、発光素子の光の一部が絶縁基体を透過して外部に漏洩するのを防ぐことができるとともに、薄型化された発光素子収納用パッケージ、およびそれを用いた発光効率がきわめて高い発光装置を提供することにある。
【０００９】
【課題を解決するための手段】
本発明の発光素子収納用パッケージは、絶縁基体の上面に発光素子を収容するための凹部が設けられ、該凹部の底面に前記発光素子が搭載される搭載部導体層および前記発光素子が電気的に接続される配線層が形成されるとともに、前記絶縁基体の下面の両端部に前記配線層および前記搭載部導体層にそれぞれ電気的に接続された２つの外部端子導体層が形成されている発光素子収納用パッケージであって、前記絶縁基体の下面の前記外部端子導体層間に、前記凹部の底面の前記絶縁基体が露出した領域と重なるように、絶縁体から成るとともに下面の略全面に導体層が形成されている板部材が接合されていることを特徴とする。
【００１０】
本発明の発光素子収納用パッケージは、絶縁基体の下面の外部端子導体層間に、凹部の底面の絶縁基体が露出した領域と重なるように、絶縁体から成るとともに下面の略全面に導体層が形成されている板部材が接合されていることから、絶縁基体の底部が薄いため発光素子の光の一部が絶縁基体の底部を透過することが可能な場合であっても、絶縁基体の底部を透過してきた光は板部材で反射もしくは吸収されるので、絶縁基体の底部を透過して漏洩することによる光の損失を防いで光を効率良く外部へ放射することができるとともに、薄型化されたものとなる。また、隣接する発光装置同士の光が混色することを防ぐこともできる。
【００１２】
本発明の発光素子収納用パッケージは、板部材は絶縁体から成るとともに下面の略全面に導体層が形成されていることから、導体層の部位で確実に外部電気回路基板に接合されるとともに接合面積が増大して強固に接続することが可能となり、また、外部電気回路基板との接合面積が増大したことにより放熱性が向上する。
【００１３】
本発明の発光装置は、本発明の発光素子収納用パッケージと、前記搭載部導体層に搭載されるとともに前記配線層に電極が電気的に接続された発光素子と、該発光素子を覆う透明樹脂とを具備していることを特徴とする。
【００１４】
本発明の発光装置は、上記の構成により、発光効率が高く、隣接する発光装置同士の光の混色を防止でき、かつ薄型化されたものとなる。
【００１５】
【発明の実施の形態】
本発明の発光素子収納用パッケージを以下に詳細に説明する。図１は、本発明のパッケージについて実施の形態の一例を示す断面図であり、同図において、１は絶縁基体、２は発光素子３の搭載部、４は発光素子３を収容するための凹部である。
【００１６】
本発明のパッケージは、絶縁基体１の上面に発光素子３を収容するための凹部４を設け、凹部４の底面に発光素子３が搭載される搭載部導体層（以下、搭載部ともいう）２および発光素子３の電極が接続される配線層５ａ，５ｂを形成するとともに、絶縁基体１の下面の両端部に配線層５ａ，５ｂと電気的に接続された外部端子導体層８ａ，８ｂが形成されているものであって、絶縁基体１の下面の外部端子導体層８ａ，８ｂ間に、凹部４の底面の絶縁基体１が露出した領域Ｒ２（図１）と重なるように、絶縁体から成るとともに下面の略全面に導体層が形成されている板部材９が接合されている。
【００１７】
なお、図１において、Ｒ１は凹部４の底面の絶縁基体１が露出していない領域を示す。
【００１８】
本発明における絶縁基体１は、酸化アルミニウム（Ａｌ_２Ｏ_３）質焼結体（アルミナセラミックス），窒化アルミニウム（ＡｌＮ）質焼結体等の焼結体（セラミックス）から成る直方体状や四角平板状のものであり、これらの白色のセラミックスは、絶縁基体１の厚みが0.8ｍｍ以上の場合に波長が400乃至700ｎｍの光の反射率を80％以上とすることができる。
【００１９】
例えば絶縁基体１が酸化アルミニウム質焼結体から成る場合、ＳｉＯ_２−Ａｌ_２Ｏ_３−ＭｇＯ−ＺｎＯ_２−ＣａＯ系等のセラミックスから成る。この場合、絶縁基体１の厚みが0.8ｍｍ以上の場合に波長が400乃至700ｎｍの光の反射率を80％以上とするには、Ａｌ_２Ｏ_３の含有量が90〜99質量％、ＳｉＯ_２，ＭｇＯ，ＣａＯの合計の含有量が１〜10質量％であることが好ましい。ＳｉＯ_２，ＭｇＯ，ＣａＯの合計の含有量が、１質量％未満では、Ａｌ_２Ｏ_３の焼結性が悪くなり、パッケージとしての十分な硬度が得られにくい。10質量％を超えると、耐熱性、機械的強度が低下するとともに熱伝導率が低下してしまう。
【００２０】
また、ＳｉＯ_２はセラミックスの焼結性と密着性、ＭｇＯとＣａＯはセラミックスの焼結性と熱伝導性を高めるためにセラミックス中に含有されており、それぞれの効果を発揮するためにも、ＳｉＯ_２，ＭｇＯ，ＣａＯのそれぞれが0.01質量％以上含有されることが好ましい。また、セラミックスの密度、機械的強度を高めるために上記セラミックス中にＺｒＯ_２を含有させても構わない。この場合、ＺｒＯ_２の含有量は0.01〜10質量％であることが好ましい。含有量が0.01質量％未満では、セラミックスの密度、機械的強度向上の効果が十分に発揮されない。10質量％を超えると、電気絶縁性が劣化する。また、ＳｉＯ_２，ＭｇＯ，ＣａＯおよびＺｒＯ_２の合計の含有量は、多すぎると耐熱性、強度が損なわれるため10質量％以下であることが好ましい。
【００２１】
また、絶縁基体１が窒化アルミニウム（ＡｌＮ）質焼結体から成る場合、ＡｌＮ−Ｅｒ_２Ｏ_３系等のセラミックスから成り、絶縁基体１の厚みが0.8ｍｍ以上で波長が400乃至700ｎｍの光の反射率が80％以上であるためには、Ｅｒ_２Ｏ_３の含有量が窒化アルミニウム質焼結体の総質量に対して１〜10質量％であることが好ましい。Ｅｒ_２Ｏ_３の含有量が１質量％未満では、焼結性が悪くなり、十分な硬度が得られにくい。10質量％を超えると、耐熱性、機械的強度が低下するとともに熱伝導率が低下してしまうこととなる。
【００２２】
この絶縁基体１は、その上面に発光素子３を収容するための凹部４が形成されており、複数のセラミック層を積層することで形成されている。例えば、凹部４用の貫通孔が形成された枠状のセラミックグリーンシートと発光素子３を搭載するための平板状のセラミックグリーンシート（以下、グリーンシートともいう）とを複数枚積層し、約1600℃で焼成し一体化することで形成されている。また、枠状のグリーンシートを１枚または複数枚積層して焼成することにより枠体を作製し、平板状のグリーンシートを１枚または複数枚積層して焼成することにより直方体状の底板部を作製し、次にこれらをロウ材や接着剤で接合して絶縁基体１を作製してもよい。
【００２３】
また、絶縁基体１の凹部４の底面には発光素子３を搭載するための搭載部２が形成されており、搭載部２はタングステン（Ｗ），モリブデン（Ｍｏ），銅（Ｃｕ），銀（Ａｇ）等の金属粉末のメタライズ層から成っている。
【００２４】
また、絶縁基体１には、搭載部２から下面にかけて導出された配線層５ａおよび搭載部２の周辺から下面にかけて導出された配線層５ｂが被着形成されている。この一対の配線層５ａ，５ｂは、ＷやＭｏ等の金属粉末のメタライズ層から成り、パッケージ内部に収納する発光素子３を外部に電気的に接続するための導電路である。そして、搭載部２には発光ダイオード（ＬＥＤ），半導体レーザ（ＬＤ）等の発光素子３が金（Ａｕ）−シリコン（Ｓｉ）合金やＡｇ−エポキシ樹脂等の導電性接合材により固着されるとともに、配線層５ｂの搭載部２の周辺の部位には発光素子３の電極がボンディングワイヤ６を介して電気的に接続されている。
【００２５】
なお、配線層５ａ，５ｂおよび搭載部２の露出する表面に、ニッケル（Ｎｉ），金（Ａｕ），Ａｇ等の耐蝕性に優れる金属を１〜20μｍ程度の厚みで被着させておくのがよく、配線層５ａ，５ｂおよび搭載部２が酸化腐蝕するのを有効に防止できるとともに、搭載部２と発光素子３との固着および配線層５ｂとボンディングワイヤ６との接続を強固にすることができる。従って、配線層５ａ，５ｂおよび搭載部２の露出表面には、厚さ１〜10μｍ程度のＮｉめっき層と厚さ0.1〜３μｍ程度のＡｕめっき層またはＡｇめっき層とが、電解めっき法や無電解めっき法により順次被着されていることがより好ましい。
【００２６】
また、凹部４の内面には金属層７が形成されており、この金属層７はＷやＭｏ等の金属粉末のメタライズ層から成り、さらに金属層７上にはＮｉ，Ａｕ，Ａｇ等の金属めっき層が被着されている。
【００２７】
凹部４の底面の配線層５ｂおよび搭載部２と、金属層７表面の金属めっき層とが、凹部４に収容される発光素子３の光を効果的に反射する反射領域として機能する。このため、凹部４の底面で絶縁基体１が露出する領域を小さくして反射性能を向上させるために、金属層７は配線層５ｂおよび搭載部２のいずれか一方と接続されていても構わない。
【００２８】
また、凹部４の内面と底面とのなす角度を35〜70°として、凹部４の内面が外側（図１では上方）に向かって漸次広がるような傾斜面となるようにすることが好ましい。この場合、凹部４の底面の配線層５ａ，５ｂおよび搭載部２、金属層７表面の金属めっき層で反射した光をパッケージの外部により効率よく放射させることができる。上記角度が35°未満では、グリーンシートを金型で打ち抜くことにより凹部４の内面をそのような角度で安定かつ効率良く形成することが困難となるとともに、パッケージが極度に大型化してしまう。70°を超えると、凹部４内に収容する発光素子３が発する光を外部に良好に反射することが困難となる。
【００２９】
また、凹部４は、その横断面形状が円形状であることが好ましい。この場合、凹部４に収容される発光素子３が発光する光を凹部４の内面の金属層７表面の金属めっき層で満遍なく反射させて外部に極めて均一に放射することができるという利点がある。
【００３０】
また、外部端子導体層８ａ，８ｂは、配線層５ａ，５ｂに電気的に接続されて絶縁基体１の下面の両端部に形成されており、Ｗ，Ｍｏ，Ｃｕ，Ａｇ等の金属粉末のメタライズ層から成っている。
【００３１】
なお、外部端子導体層８ａ，８ｂは、その表面にＮｉ，Ａｕ，Ａｇ等の耐蝕性に優れる金属を１〜20μｍ程度の厚みで被着させておくのがよく、外部端子導体層８ａ，８ｂが酸化腐蝕するのを有効に防止できるとともに、絶縁基体１の下面をはんだ等の接合材を介して外部電気回路基板に良好に接続することができる。
【００３２】
さらに、外部端子導体層８ａ，８ｂは絶縁基体１の側面に延出されていてもよく、光が絶縁基体１の側面から外部に漏洩するのを防ぐことができる。この場合、外部端子導体層８ａ，８ｂは、絶縁基体１の側面に下面と凹部４の底面との間の高さの１／４以上に延出して形成されていることがよく、光が絶縁基体１の側面から外部に漏洩するのをより有効に防ぐことができる。
【００３３】
本発明の板部材９は、絶縁基体１の下面の外部端子導体層８ａ，８ｂ間に接合されており、板部材９は、凹部４の底面の搭載部２と配線層５ａ，５ｂとの間の絶縁基体１が露出した領域Ｒ２と重なるように配置されている。これにより、領域Ｒ２から絶縁基体１の底部に侵入し透過した一部の光は、領域Ｒ２を覆う板部材９によって反射もしくは吸収され、光が絶縁基体１の下面から外部に漏れ出るのを防ぐことができる。
【００３４】
この場合、領域Ｒ２から絶縁基体１の底部に侵入する光は、底面に対して直交しない方向（斜め方向）の成分もあるため、Ｒ１をも板部材９で覆うことにより、斜め方向の光を反射もしくは吸収することができる。また、板部材９は広い領域に接合されていることがよく、上記の斜め方向の光を効果的に反射もしくは吸収して外部に漏洩するのをより有効に防ぐことができる。
【００３５】
また、搭載部２の周囲の底面が露出した領域Ｒ２のうち、搭載部２と配線層５ｂとの間の絶縁基体１の底面が露出した領域Ｒ２が大きく、この領域Ｒ２の直下の部位が板部材９で覆われていることにより、光の外部への漏洩を有効に防ぐことができる。
【００３６】
本発明の板部材９は、酸化アルミニウム質焼結体，窒化アルミニウム質焼結体，ムライト質焼結体，ガラスセラミックス質焼結体等のセラミックス、エポキシ樹脂，アクリル樹脂，ポリカーボネート，フェノール樹脂，シリコーン樹脂等の樹脂、Ａｌ，Ｃｕ，Ｎｉ，Ａｇ，ステンレススチール，真鍮（Ｃｕ−Ｚｎ合金），Ｆｅ−Ｎｉ合金，Ｆｅ−Ｎｉ−Ｃｏ合金，Ｃｕ−Ｗ合金等の金属など不透明な材料から成り、絶縁基体１の下面にエポキシ等の樹脂接着剤、Ａｇロウ，Ｐｂ−Ｓｎ系はんだ，Ｐｂフリーはんだ等のロウ材等からなる接合材を介して接合されている。
【００３７】
この板部材９は、絶縁基体１がアルミナセラミックス等のセラミックスから成る場合、それに熱膨張係数が同じか近似したアルミナセラミックス等のセラミックス，Ｆｅ−Ｎｉ合金，Ｆｅ−Ｎｉ−Ｃｏ合金等から成るのがよい。また、板部材９が熱伝導性が高いＣｕ−Ｗ合金等から成っていてもよく、この場合発光装置の放熱性が向上する。
【００３８】
なお、板部材９が白色等の明色のものから成る場合、凹部４の底面が露出した領域Ｒ２から侵入し絶縁基体１の底部を透過した光を効率よく反射することができ、板部材９が黒色等の暗色のものから成る場合、凹部４の底面が露出した領域Ｒ２から侵入し絶縁基体１の底部を透過した光を吸収することができ、共に光が外部に漏洩するのを有効に防ぐことができる。
【００３９】
また、本発明の板部材９がセラミックスや樹脂等の絶縁体から成り、図３のパッケージの断面図、図４の下面図に示すように、板部材９の下面の略全面に導体層１０が形成されている。このことから、パッケージを外部電気回路基板にはんだ等のロウ材を介して接合する際、絶縁基体１の下面を外部端子導体層８ａ，８ｂとともに導体層１０により接合することとなり、接合面積が増大して強固に接合することができるとともに、外部電気回路基板との接合面積が増大したことにより放熱性が向上する。
【００４０】
なお、板部材９の下面の略全面に導体層10が形成されているが、略全面とは、例えば図５に示すように板部材９の下面の外周部に全周にわたって凸部９ａを形成する場合もあるため、必ずしも板部材９の下面の全面に導体層10が形成されていなくてもよいことを意味するものである。
【００４１】
導体層10は、板部材９がセラミックスから成る場合、Ｗ，Ｍｏ，Ｃｕ，Ａｇ等の金属粉末のメタライズ層から成り、その表面にＮｉ，Ａｕ，Ａｇ等の耐蝕性に優れる金属を１〜20μｍ程度の厚みで被着させておくのがよく、導体層10が酸化腐蝕するのを有効に防止できるとともに、絶縁基体１の下面が導体層10の部位ではんだ等の接合材を介して外部電気回路基板に接合され、放熱性が向上する。従って、導体層10の表面には、厚さ１〜10μｍ程度のＮｉめっき層と、厚さ0.1〜３μｍ程度のＡｕめっき層またはＡｇめっき層とが、電解めっき法や無電解めっき法により順次被着されていることがより好ましい。
【００４２】
また導体層10は、板部材９が樹脂から成る場合、めっき法、蒸着法、スパッタリング法、金属箔転写法等により、Ｃｕ，Ｎｉ，Ａｕ，Ａｇ等の金属を被着させて成り、板部材９がセラミックスから成る場合と同様に、その表面にＮｉ，Ａｕ，Ａｇ等の耐蝕性に優れる金属を１〜20μｍ程度の厚みで被着させておくのがよい。
【００４３】
さらに、絶縁基体１の下面をはんだ等の接合材を介して外部電気回路基板に接続する際、各外部端子導体層８ａ，８ｂと導体層10との間隔が小さい場合、短絡するのを有効に防止するため、図５のパッケージ断面図、図６の下面図に示すように、板部材９の下面の外周部に全周にわたって幅0.05〜2.0ｍｍ程度の凸部９ａを設けて、凸部９ａによって外部端子導体層８ａ，８ｂと導体層10とが接触しないようにしてもよい。
【００４４】
なお、凸部９ａは図６（ａ）のように板部材９周縁の各外部端子導体層８ａ，８ｂと導体層10との間の部位にのみ設けてもよいし、図６（ｂ）のように板部材９周縁全体に設けてもよい。また凸部９ａは、その厚みが導体層10の厚みよりも厚いのがよい。この場合、凸部９ａによって絶縁基体１を支持固定することができる。さらに、絶縁基体１の下面をはんだ等の接合材を介して外部電気回路基板に接続する際は接合材が溶融した状態であり、パッケージが外部電気回路基板に対して傾いたまま接合されようとしても、凸部９ａが外部電気回路基板に当接することにより外部電気回路基板とパッケージとが略平行となって接続される。その結果、発光装置の光がより確実に所定の方向へ放射されることとなる。
【００４５】
本発明において、絶縁基体１の下面と板部材９の下面（接合材、凸部９ａ、導体層10も含む）との間の厚みは、外部端子導体層８ａ，８ｂよりも0.01〜1ｍｍ厚いのがよい。この場合、絶縁基体１の下面が広面積の板部材９や導体層10の部位で確実に外部電気回路基板やパッケージに当接もしくは接合され、放熱性が向上するとともに、外部端子導体層８ａ，８ｂにおいてはんだ等のロウ材の量が多くなってロウ材の大きなメニスカスが形成され、外部端子導体層８ａ，８ｂの接合強度が大きくなる。その結果、外部端子導体層８ａ，８ｂの接合性が良好になるとともに接合部の抵抗が小さくなり、発光素子３の発光効率が向上する。
【００４６】
また、本発明のパッケージは、発光素子３の光の一部が板部材９を透過することが可能な場合であっても、板部材９を透過してきた光は導体層10で反射されるので、絶縁基体１の底部さらには板部材９を透過して漏洩することによる光の損失を防いで光を効率良く外部へ放射することができるとともに、薄型化されたものとなる。
【００４７】
かくして、本発明のパッケージは、板部材９が、凹部４の底面で絶縁基体１が露出した領域Ｒ２と重なるように配置されていることから、絶縁基体１の底部が薄いため発光素子３の光の一部が絶縁基体１の底部を透過することが可能な場合であっても、絶縁基体１の底部を透過してきた光は板部材９で反射もしくは吸収されて、絶縁基体の底部を透過し外部に漏洩することによる光の損失を防いで光を効率良く外部へ放射するのを防ぐことができるとともに、薄型化されたものとなる。
【００４８】
また、本発明のパッケージは、板部材９が絶縁体から成るとともに下面の略全面に導体層10が形成されていることから、導体層10の部位で確実に外部電気回路基板に接合され、放熱性が向上する。
【００４９】
本発明の発光装置は、本発明のパッケージと、搭載部２に搭載されるとともに搭載部２の周囲の配線導体５ｂに電気的に接続された発光素子３と、発光素子３を覆うシリコーン樹脂，エポキシ樹脂等の透明樹脂とを具備したことにより、発光効率が高く、隣接する発光装置同士の光の混色防止ができかつ薄型化されたものとなる。発光素子３を覆う透明樹脂は、発光素子３およびその周囲を覆っていてもよいし、凹部４に充填されて発光素子３を覆っていてもよい。
【００５０】
なお、本発明は上述の実施の形態に限定されず、本発明の要旨を逸脱しない範囲内で種々の変更を施すことは何等差し支えない。例えば、図７のパッケージの断面図、図８の下面図に示すように、パッケージの下面をはんだ等の接合材を介して外部電気回路基板により強固に接続するため、絶縁基体１の下面の両端部に形成された外部端子導体層８ａ，８ｂを大きくし、搭載部２と金属層７、配線層５ｂと金属層７との間にある絶縁基体１が露出した領域Ｒ３とそれぞれ重なるように外部端子導体層８ａ，８ｂが形成されていてもよい。この場合、領域Ｒ３から絶縁基体１の底部に侵入し透過した一部の光は、領域Ｒ３を覆う外部端子導体層８ａ，８ｂによって反射され、光が絶縁基体１の下面から外部に漏れ出るのを防ぐことができる。したがって、この場合、凹部４の底面の搭載部２と配線層５ｂとの間にある絶縁基体１が露出した領域Ｒ２と重なるように板部材９が接合されていればよい。
【００５１】
【発明の効果】
本発明の発光素子収納用パッケージは、絶縁基体の上面に発光素子を収容するための凹部が設けられ、凹部の底面に発光素子が搭載される搭載部導体層および発光素子が電気的に接続される配線層が形成されるとともに、絶縁基体の下面の両端部に配線層および搭載部導体層にそれぞれ電気的に接続された２つの外部端子導体層が形成されているものであって、絶縁基体の下面の外部端子導体層間に、凹部の底面の絶縁基体が露出した領域と重なるように、絶縁体から成るとともに下面の略全面に導体層が形成されている板部材が接合されていることにより、絶縁基体の底部が薄いため発光素子の光の一部が絶縁基体の底部を透過することが可能な場合であっても、絶縁基体の底部を透過してきた光は板部材で反射もしくは吸収されるので、光が絶縁基体の底部を透過して外部に漏洩することによる光の損失を防いで光を効率良く外部へ放射することができるとともに、薄型化されたものとなる。また、隣接する発光装置同士の光が混色することを防ぐこともできる。
【００５２】
また、本発明の発光素子収納用パッケージは、板部材は絶縁体から成るとともに下面の略全面に導体層が形成されていることから、導体層の部位で確実に外部電気回路基板に接合されるとともに接合面積が増大して強固に接続することが可能となり、また、外部電気回路基板との接合面積が増大したことにより放熱性が向上する。
【００５３】
本発明の発光装置は、本発明の発光素子収納用パッケージと、搭載部導体層に搭載されるとともに搭載部導体層の周囲の配線導体に電気的に接続された発光素子と、発光素子を覆う透明樹脂とを具備したことにより、発光効率が高く、隣接する発光装置同士の光の混色防止ができかつ薄型化されたものとなる。
【図面の簡単な説明】
【図１】本発明の発光素子収納用パッケージについて実施の形態の一例を示す断面図である。
【図２】図１の発光素子収納用パッケージの下面図である。
【図３】本発明の発光素子収納用パッケージについて実施の形態の他の例を示す断面図である。
【図４】図３の発光素子収納用パッケージの下面図である。
【図５】本発明の発光素子収納用パッケージについて実施の形態の他の例を示す断面図である。
【図６】図５の発光素子収納用パッケージについて実施の形態の他の例を示し、（ａ），（ｂ）はそれぞれ発光素子収納用パッケージの下面図である。
【図７】本発明の発光素子収納用パッケージについて実施の形態の他の例を示す断面図である。
【図８】図７の発光素子収納用パッケージの下面図である。
【図９】従来の発光素子収納用パッケージの断面図である。
【図１０】図９の発光素子収納用パッケージの下面図である。
【符号の説明】
１：絶縁基体
２：搭載部導体層
３：発光素子
４：凹部
５ａ，５ｂ：配線層
８ａ，８ｂ：外部端子導体層
９：板部材
９ａ：凸部
10：導体層[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light-emitting element storage package and a light-emitting device for storing a light-emitting element, which are used in a display device using a light-emitting element such as a light-emitting diode.
[0002]
[Prior art]
Conventionally, a ceramic package has been used as a light emitting element storage package (hereinafter also referred to as a package) for storing a light emitting element such as a light emitting diode, and an example thereof is shown in FIG. Reference 1). As shown in the figure, the conventional package is formed by laminating a plurality of ceramic layers and has a recess 14 formed on the top surface, and a mounting portion conductor layer 12 comprising a conductor layer for mounting the light emitting element 13 on the bottom surface. (Hereinafter also referred to as a mounting portion) a rectangular parallelepiped insulating base 11, and a wiring layer 15 comprising a pair of metallized wiring conductors led out from the mounting portion 12 of the insulating base 11 and its periphery to the lower surface of the insulating base 11. And is composed mainly of.
[0003]
Then, the light emitting element 13 is placed and fixed on the mounting portion 12 to which one end of one wiring layer 15 is electrically connected via a conductive adhesive, solder, etc., and the electrode of the light emitting element 13 and the other wiring The layer 15 is electrically connected via the bonding wire 16, and then the light emitting device 13 is sealed by filling the recess 14 of the insulating substrate 11 with a transparent resin and sealing the light emitting element 13.
[0004]
Since many of the light emitting devices are arranged so as to be adjacent to each other, the light emitted from the light emitting element 13 mounted on the mounting portion 12 is transmitted through the insulating base 11 in the ceramic package. Thus, in order to effectively prevent light from mixing between adjacent light emitting devices, the insulating base 11 made of ceramics is used. Further, in order to reflect the light of the light emitting element 13 on the inner surface of the recess 14 and to emit light above the package, the metallization having a nickel (Ni) plating layer or a gold (Au) plating layer on the inner surface of the recess 14 on the surface. A metal layer 17 composed of layers may be applied.
[0005]
[Patent Document 1]
JP 2002-232017 Gazette [0006]
[Problems to be solved by the invention]
However, in the conventional package described above, an exposed ceramic is exposed between the mounting portion 12 and the wiring layer 15 of the insulating base 11 and the metal layer 17 on the inner surface of the recess 14 in order to prevent an electrical short circuit. However, if the insulating substrate 11 is thickened, the light from the light emitting element 13 is not transmitted through the insulating substrate 11 and leaks outside, and the light from the light emitting element 13 is efficiently emitted to the outside of the package. However, there is a problem that the package becomes large. On the other hand, when the insulating base 11 is thinned, the package is downsized, but a part of the light of the light emitting element 13 passes through the insulating base 11 and leaks to the outside, which reduces the light emission efficiency of the light emitting device. There is also a problem in that light from adjacent light emitting devices is mixed in color.
[0007]
Further, when the mounting portion 12 is formed on the entire bottom surface of the recess 14 and the wiring layer 15 is formed around the inner surface (inner surface) of the recess 14 or the recess 14 on the upper surface of the insulating substrate 11, it is difficult to connect the bonding wires 16. Or the size of the light emitting device itself is increased.
[0008]
Therefore, the present invention has been completed in view of the above-mentioned conventional problems, and its purpose is to prevent a part of the light of the light emitting element from leaking outside through the insulating substrate, It is an object of the present invention to provide a light-emitting element storage package that is thinned and a light-emitting device that uses the light-emitting element and has extremely high light emission efficiency.
[0009]
[Means for Solving the Problems]
In the light emitting element storage package of the present invention, a concave portion for accommodating the light emitting element is provided on the upper surface of the insulating base, and the mounting portion conductor layer on which the light emitting element is mounted and the light emitting element are electrically mounted on the bottom surface of the concave portion. And a wiring layer connected to each other, and two external terminal conductor layers electrically connected to the wiring layer and the mounting portion conductor layer, respectively, are formed at both ends of the lower surface of the insulating base. An element storage package comprising an insulator and a conductor layer on substantially the entire bottom surface of the bottom surface of the recess so as to overlap with the exposed region of the bottom surface of the recess between the external terminal conductor layers on the bottom surface of the insulating substrate. The board member in which is formed is joined.
[0010]
The light emitting element storage package according to the present invention is made of an insulator and has a conductor layer formed on substantially the entire bottom surface so as to overlap with the exposed region of the bottom surface of the recess between the external terminal conductor layers on the bottom surface of the insulating substrate. Since the bottom plate of the insulating base is thin, the bottom of the insulating base can be removed even when a part of the light from the light emitting element can pass through the bottom of the insulating base. Since the transmitted light is reflected or absorbed by the plate member, it is possible to efficiently radiate the light to the outside by preventing light loss due to leakage through the bottom of the insulating base, and the thickness is reduced. It will be a thing. In addition, it is possible to prevent light from being mixed between adjacent light emitting devices.
[0012]
In the light emitting element storage package of the present invention, since the plate member is made of an insulator and the conductor layer is formed on substantially the entire lower surface, it is securely bonded to the external electric circuit board at the portion of the conductor layer and bonded. The area can be increased and a strong connection can be achieved, and the heat dissipation can be improved due to the increased area of bonding with the external electric circuit board.
[0013]
The light emitting device of the present invention includes a light emitting element housing package of the present invention, a light emitting element mounted on the mounting portion conductor layer and having an electrode electrically connected to the wiring layer, and a transparent resin covering the light emitting element It is characterized by comprising.
[0014]
The light emitting device of the present invention has high luminous efficiency, can prevent light from being mixed between adjacent light emitting devices, and is thinned by the above configuration.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
The light emitting element storage package of the present invention will be described in detail below. FIG. 1 is a cross-sectional view showing an example of an embodiment of a package of the present invention, in which 1 is an insulating substrate, 2 is a mounting portion for a light emitting element 3, and 4 is a recess for housing the light emitting element 3. It is.
[0016]
The package of the present invention is provided with a recess 4 for accommodating the light emitting element 3 on the upper surface of the insulating base 1, and a mounting portion conductor layer (hereinafter also referred to as a mounting portion) 2 on which the light emitting element 3 is mounted on the bottom surface of the recess 4. And wiring layers 5a and 5b to which the electrodes of the light emitting element 3 are connected, and external terminal conductor layers 8a and 8b electrically connected to the wiring layers 5a and 5b are formed at both ends of the lower surface of the insulating substrate 1. The insulating base 1 is made of an insulating material so that it overlaps the region R2 (FIG. 1) where the insulating base 1 on the bottom surface of the recess 4 is exposed between the external terminal conductor layers 8a and 8b on the bottom surface of the insulating base 1. At the same time, a plate member 9 having a conductor layer formed on substantially the entire bottom surface is joined.
[0017]
In FIG. 1, R1 indicates a region of the bottom surface of the recess 4 where the insulating base 1 is not exposed.
[0018]
The insulating substrate 1 in the present invention has a rectangular parallelepiped shape or a square plate shape made of a sintered body (ceramics) such as an aluminum oxide (Al ₂ O ₃ ) sintered body (alumina ceramics) or an aluminum nitride (AlN) sintered body. These white ceramics can make the reflectance of light having a wavelength of 400 to 700 nm 80% or more when the thickness of the insulating substrate 1 is 0.8 mm or more.
[0019]
For example, when the insulating substrate 1 is made of an aluminum oxide sintered body, it is made of a ceramic such as SiO ₂ —Al ₂ O ₃ —MgO—ZnO ₂ —CaO. In this case, in order that the reflectance of light having a wavelength of 400 to 700 nm is 80% or more when the thickness of the insulating substrate 1 is 0.8 mm or more, the content of Al ₂ O ₃ is 90 to 99% by mass, SiO ₂ The total content of MgO and CaO is preferably 1 to 10% by mass. When the total content of SiO ₂ , MgO, and CaO is less than 1% by mass, the sinterability of Al ₂ O ₃ is deteriorated, and it is difficult to obtain sufficient hardness as a package. If it exceeds 10% by mass, the heat resistance and mechanical strength are lowered and the thermal conductivity is lowered.
[0020]
In addition, SiO ₂ is contained in ceramics in order to enhance the sinterability and adhesiveness of ceramics, and MgO and CaO are included in ceramics in order to enhance the sinterability and thermal conductivity of ceramics. ₂ , MgO and CaO are each preferably contained in an amount of 0.01% by mass or more. Further, ZrO ₂ may be contained in the ceramics in order to increase the density and mechanical strength of the ceramics. In this case, the content of ZrO ₂ is preferably 0.01 to 10% by mass. When the content is less than 0.01% by mass, the effect of improving the density and mechanical strength of the ceramics is not sufficiently exhibited. If it exceeds 10% by mass, the electrical insulation properties deteriorate. Further, if the total content of SiO ₂ , MgO, CaO and ZrO ₂ is too large, the heat resistance and strength are impaired, and therefore it is preferably 10% by mass or less.
[0021]
Further, when the insulating base 1 is made of an aluminum nitride (AlN) -based sintered body, it is made of an AlN—Er ₂ O ₃ based ceramic, and the insulating base 1 has a thickness of 0.8 mm or more and a wavelength of 400 to 700 nm. In order for the reflectance to be 80% or more, the content of Er ₂ O ₃ is preferably 1 to 10% by mass with respect to the total mass of the aluminum nitride sintered body. When the content of Er ₂ O ₃ is less than 1% by mass, the sinterability is deteriorated and it is difficult to obtain sufficient hardness. If it exceeds 10% by mass, the heat resistance and mechanical strength are lowered and the thermal conductivity is lowered.
[0022]
The insulating base 1 has a recess 4 for accommodating the light emitting element 3 on its upper surface, and is formed by laminating a plurality of ceramic layers. For example, a plurality of frame-shaped ceramic green sheets in which through holes for the recesses 4 are formed and flat ceramic green sheets (hereinafter also referred to as green sheets) for mounting the light-emitting elements 3 are stacked, and about 1600 It is formed by firing and integrating at a temperature. Also, a frame body is produced by laminating one or more frame-shaped green sheets and firing, and a rectangular parallelepiped bottom plate portion is fabricated by laminating one or more plate-shaped green sheets and firing. Then, the insulating substrate 1 may be manufactured by bonding them with a brazing material or an adhesive.
[0023]
Further, a mounting portion 2 for mounting the light emitting element 3 is formed on the bottom surface of the recess 4 of the insulating substrate 1, and the mounting portion 2 is made of tungsten (W), molybdenum (Mo), copper (Cu), silver ( It consists of a metallized layer of metal powder such as Ag).
[0024]
The insulating base 1 is formed with a wiring layer 5a led out from the mounting portion 2 to the lower surface and a wiring layer 5b led out from the periphery of the mounting portion 2 to the lower surface. The pair of wiring layers 5a and 5b is made of a metallized layer of metal powder such as W or Mo, and is a conductive path for electrically connecting the light emitting element 3 housed in the package to the outside. A light emitting element 3 such as a light emitting diode (LED) or a semiconductor laser (LD) is fixed to the mounting portion 2 with a conductive bonding material such as gold (Au) -silicon (Si) alloy or Ag-epoxy resin. The electrode of the light emitting element 3 is electrically connected to the portion around the mounting portion 2 of the wiring layer 5 b through the bonding wire 6.
[0025]
It should be noted that a metal having excellent corrosion resistance such as nickel (Ni), gold (Au), Ag or the like is deposited on the exposed surfaces of the wiring layers 5a and 5b and the mounting portion 2 in a thickness of about 1 to 20 μm. It is possible to effectively prevent the wiring layers 5a and 5b and the mounting portion 2 from being oxidized and corroded, and to firmly fix the mounting portion 2 and the light emitting element 3 and to connect the wiring layer 5b and the bonding wire 6 to each other. it can. Therefore, on the exposed surfaces of the wiring layers 5a and 5b and the mounting portion 2, an Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer or an Ag plating layer having a thickness of about 0.1 to 3 μm are formed by an electroplating method or a method. More preferably, the electrodes are sequentially deposited by electrolytic plating.
[0026]
In addition, a metal layer 7 is formed on the inner surface of the recess 4, and this metal layer 7 is made of a metallized layer of metal powder such as W or Mo. Further, on the metal layer 7, a metal such as Ni, Au, Ag, etc. A plating layer is applied.
[0027]
The wiring layer 5b and the mounting portion 2 on the bottom surface of the recess 4 and the metal plating layer on the surface of the metal layer 7 function as a reflection region that effectively reflects the light of the light emitting element 3 accommodated in the recess 4. Therefore, the metal layer 7 may be connected to either the wiring layer 5b or the mounting portion 2 in order to reduce the region where the insulating base 1 is exposed at the bottom surface of the recess 4 and improve the reflection performance. .
[0028]
Moreover, it is preferable that the angle formed between the inner surface and the bottom surface of the recess 4 is 35 to 70 ° so that the inner surface of the recess 4 becomes an inclined surface that gradually spreads outward (upward in FIG. 1). In this case, the light reflected by the wiring layers 5a and 5b on the bottom surface of the recess 4 and the metal plating layer on the surface of the mounting portion 2 and the metal layer 7 can be efficiently emitted outside the package. If the angle is less than 35 °, it becomes difficult to stably and efficiently form the inner surface of the recess 4 at such an angle by punching the green sheet with a mold, and the package becomes extremely large. If it exceeds 70 °, it will be difficult to satisfactorily reflect the light emitted from the light emitting element 3 accommodated in the recess 4 to the outside.
[0029]
Moreover, it is preferable that the cross-sectional shape of the recessed part 4 is circular. In this case, there is an advantage that light emitted from the light emitting element 3 accommodated in the recess 4 can be uniformly reflected by the metal plating layer on the surface of the metal layer 7 on the inner surface of the recess 4 and radiated to the outside very uniformly.
[0030]
The external terminal conductor layers 8a and 8b are electrically connected to the wiring layers 5a and 5b and are formed at both ends of the lower surface of the insulating base 1, and metallized with a metal powder such as W, Mo, Cu, or Ag. Consists of layers.
[0031]
The external terminal conductor layers 8a and 8b are preferably coated with a metal having excellent corrosion resistance, such as Ni, Au, and Ag, on the surface thereof to a thickness of about 1 to 20 μm. The external terminal conductor layers 8a and 8b Can be effectively prevented from being oxidized and corroded, and the lower surface of the insulating base 1 can be satisfactorily connected to the external electric circuit board via a bonding material such as solder.
[0032]
Furthermore, the external terminal conductor layers 8a and 8b may be extended to the side surface of the insulating base 1, and light can be prevented from leaking from the side of the insulating base 1 to the outside. In this case, the external terminal conductor layers 8a and 8b are preferably formed on the side surface of the insulating base 1 so as to extend to ¼ or more of the height between the lower surface and the bottom surface of the concave portion 4 so that the light is insulated. It is possible to more effectively prevent leakage from the side surface of the substrate 1 to the outside.
[0033]
The plate member 9 of the present invention is joined between the external terminal conductor layers 8a and 8b on the lower surface of the insulating base 1, and the plate member 9 is interposed between the mounting portion 2 on the bottom surface of the recess 4 and the wiring layers 5a and 5b. The insulating base 1 is disposed so as to overlap the exposed region R2. As a result, part of the light that has entered and transmitted from the region R2 to the bottom of the insulating substrate 1 is reflected or absorbed by the plate member 9 that covers the region R2, and prevents light from leaking outside from the lower surface of the insulating substrate 1. be able to.
[0034]
In this case, since light entering the bottom of the insulating base 1 from the region R2 has a component in a direction (oblique direction) that is not orthogonal to the bottom surface, covering the R1 with the plate member 9 also allows light in the oblique direction to be covered. Can be reflected or absorbed. Further, the plate member 9 is preferably joined to a wide area, and can effectively prevent the light in the oblique direction from being reflected or absorbed and leaked to the outside.
[0035]
Of the region R2 in which the bottom surface around the mounting portion 2 is exposed, the region R2 in which the bottom surface of the insulating base 1 between the mounting portion 2 and the wiring layer 5b is exposed is large, and the portion immediately below the region R2 is a plate. By being covered with the member 9, leakage of light to the outside can be effectively prevented.
[0036]
The plate member 9 of the present invention includes ceramics such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, and a glass ceramic sintered body, epoxy resin, acrylic resin, polycarbonate, phenol resin, and silicone. It is made of an opaque material such as resin such as resin, Al, Cu, Ni, Ag, stainless steel, brass (Cu—Zn alloy), Fe—Ni alloy, Fe—Ni—Co alloy, Cu—W alloy, etc. The insulating base 1 is bonded to the lower surface via a bonding material made of a resin adhesive such as epoxy, a brazing material such as Ag brazing, Pb—Sn solder, Pb free solder, or the like.
[0037]
When the insulating base 1 is made of ceramics such as alumina ceramics, the plate member 9 is made of ceramics such as alumina ceramics, Fe—Ni alloy, Fe—Ni—Co alloy or the like having the same or similar thermal expansion coefficient. Good. Further, the plate member 9 may be made of a Cu—W alloy or the like having high thermal conductivity, and in this case, the heat dissipation of the light emitting device is improved.
[0038]
When the plate member 9 is made of a light color such as white, the light that has entered the region R2 where the bottom surface of the recess 4 is exposed and has transmitted through the bottom of the insulating substrate 1 can be efficiently reflected. Can be absorbed from the region R2 where the bottom surface of the recess 4 is exposed and transmitted through the bottom portion of the insulating substrate 1, and both can effectively leak light to the outside. Can be prevented.
[0039]
Further, the plate member 9 of the present invention Ri formed of an insulating material such as a ceramic or resin, cross-sectional view of the package of FIG. 3, as shown in the bottom view of FIG. 4, the conductor layer on substantially the entire surface of the lower surface of the plate member 9 10 but that has been formed. Therefore, when joined via a brazing material such as solder the package to an external electric circuit board, the lower surface of the external terminal conductor layer 8a of the insulating substrate 1, will be joined by a conductor layer 10 with 8b, the bonding area is increased As a result, the heat dissipation can be improved by increasing the bonding area with the external electric circuit board.
[0040]
The conductor layer 10 is formed on substantially the entire lower surface of the plate member 9. The substantially entire surface means that, for example, a convex portion 9a is formed on the entire outer periphery of the lower surface of the plate member 9 as shown in FIG. This means that the conductor layer 10 does not necessarily have to be formed on the entire lower surface of the plate member 9.
[0041]
When the plate member 9 is made of ceramics, the conductor layer 10 is made of a metallized layer of metal powder such as W, Mo, Cu, Ag, etc., and a metal having excellent corrosion resistance such as Ni, Au, Ag, etc. on the surface thereof is 1-20 μm. It is preferable that the conductive layer 10 be deposited to a certain thickness, and the conductive layer 10 can be effectively prevented from being oxidatively corroded, and the lower surface of the insulating substrate 1 can be externally connected to the conductive layer 10 through a bonding material such as solder. Bonded to the circuit board, heat dissipation is improved. Therefore, a Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer or an Ag plating layer having a thickness of about 0.1 to 3 μm are sequentially coated on the surface of the conductor layer 10 by an electrolytic plating method or an electroless plating method. More preferably it is worn.
[0042]
When the plate member 9 is made of a resin, the conductor layer 10 is formed by depositing a metal such as Cu, Ni, Au, or Ag by a plating method, a vapor deposition method, a sputtering method, a metal foil transfer method, or the like. Similarly to the case where 9 is made of ceramics, it is preferable that a metal having excellent corrosion resistance such as Ni, Au, Ag, etc. is deposited on the surface thereof with a thickness of about 1 to 20 μm.
[0043]
Further, when the lower surface of the insulating base 1 is connected to the external electric circuit board via a bonding material such as solder, it is effective to short-circuit if the distance between the external terminal conductor layers 8a and 8b and the conductor layer 10 is small. In order to prevent this, as shown in the package cross-sectional view of FIG. 5 and the bottom view of FIG. 6, a convex portion 9a having a width of about 0.05 to 2.0 mm is provided on the outer peripheral portion of the lower surface of the plate member 9 over the entire circumference. Therefore, the external terminal conductor layers 8a and 8b and the conductor layer 10 may not be in contact with each other.
[0044]
In addition, the convex part 9a may be provided only in the site | part between each external terminal conductor layer 8a, 8b and the conductor layer 10 of the board member 9 periphery like FIG. 6 (a), or FIG.6 (b). Thus, the plate member 9 may be provided over the entire periphery. Further, the thickness of the convex portion 9 a is preferably larger than the thickness of the conductor layer 10. In this case, the insulating substrate 1 can be supported and fixed by the convex portion 9a. Further, when the lower surface of the insulating base 1 is connected to the external electric circuit board via a bonding material such as solder, the bonding material is in a molten state, and the package is about to be bonded while being inclined with respect to the external electric circuit board. In addition, when the convex portion 9a contacts the external electric circuit board, the external electric circuit board and the package are connected in parallel. As a result, light from the light emitting device is more reliably emitted in a predetermined direction.
[0045]
In the present invention, the thickness between the lower surface of the insulating substrate 1 and the lower surface of the plate member 9 (including the bonding material, the convex portion 9a, and the conductor layer 10) is 0.01 to 1 mm thicker than the external terminal conductor layers 8a and 8b. Is good. In this case, the lower surface of the insulating substrate 1 is reliably brought into contact with or joined to the external electric circuit board or package at the plate member 9 or conductor layer 10 having a large area, so that heat dissipation is improved and the external terminal conductor layer 8a, In 8b, the amount of brazing material such as solder increases and a large meniscus of brazing material is formed, and the bonding strength of the external terminal conductor layers 8a and 8b increases. As a result, the jointability of the external terminal conductor layers 8a and 8b is improved and the resistance of the joint portion is reduced, and the light emission efficiency of the light emitting element 3 is improved.
[0046]
In the package of the present invention, even if a part of the light of the light emitting element 3 can pass through the plate member 9, the light transmitted through the plate member 9 is reflected by the conductor layer 10. In addition, the loss of light due to leakage through the bottom of the insulating substrate 1 and further through the plate member 9 can be prevented and light can be radiated efficiently to the outside, and the thickness is reduced.
[0047]
Thus, in the package of the present invention, since the plate member 9 is arranged so as to overlap the region R2 where the insulating base 1 is exposed at the bottom surface of the concave portion 4, the bottom of the insulating base 1 is thin, so Even if a part of the light can pass through the bottom of the insulating base 1, the light transmitted through the bottom of the insulating base 1 is reflected or absorbed by the plate member 9 and passes through the bottom of the insulating base 1. The loss of light due to leakage to the outside can be prevented, and light can be prevented from being efficiently emitted to the outside, and the thickness can be reduced.
[0048]
In the package of the present invention, since the plate member 9 is made of an insulator and the conductor layer 10 is formed on substantially the entire lower surface, the conductor layer 10 is reliably joined to the external electric circuit board at the portion of the conductor layer 10 to dissipate heat. Improves.
[0049]
The light emitting device of the present invention includes a package of the present invention, a light emitting element 3 mounted on the mounting portion 2 and electrically connected to the wiring conductor 5b around the mounting portion 2, a silicone resin covering the light emitting element 3, By providing a transparent resin such as an epoxy resin, light emission efficiency is high, color mixing of light between adjacent light emitting devices can be prevented, and the thickness is reduced. The transparent resin that covers the light emitting element 3 may cover the light emitting element 3 and the periphery thereof, or may fill the concave portion 4 and cover the light emitting element 3.
[0050]
It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention. For example, as shown in the cross-sectional view of the package of FIG. 7 and the bottom view of FIG. 8, both ends of the lower surface of the insulating base 1 are connected to the external electric circuit board more firmly through a bonding material such as solder. The external terminal conductor layers 8a and 8b formed in the portion are enlarged, and the external terminal conductor layers 8a and 8b are overlapped with the exposed region R3 between the mounting portion 2 and the metal layer 7 and between the wiring layer 5b and the metal layer 7, respectively. Terminal conductor layers 8a and 8b may be formed. In this case, part of the light that has entered and transmitted from the region R3 to the bottom of the insulating base 1 is reflected by the external terminal conductor layers 8a and 8b covering the region R3, and the light leaks outside from the lower surface of the insulating base 1. Can be prevented. Therefore, in this case, the plate member 9 only needs to be joined so as to overlap the region R2 where the insulating substrate 1 is exposed between the mounting portion 2 on the bottom surface of the recess 4 and the wiring layer 5b.
[0051]
【The invention's effect】
In the light emitting element storage package of the present invention, a recess for receiving the light emitting element is provided on the top surface of the insulating base, and the mounting portion conductor layer on which the light emitting element is mounted and the light emitting element are electrically connected to the bottom surface of the recess. And two external terminal conductor layers electrically connected to the wiring layer and the mounting portion conductor layer, respectively, are formed at both ends of the lower surface of the insulating base, A plate member made of an insulator and having a conductor layer formed on substantially the entire bottom surface thereof is joined between the external terminal conductor layers on the bottom surface of the substrate so as to overlap the exposed area of the insulating base on the bottom surface of the recess. Even if a part of the light of the light emitting element can be transmitted through the bottom of the insulating substrate because the bottom of the insulating substrate is thin, the light transmitted through the bottom of the insulating substrate is reflected or absorbed by the plate member. So There it is possible to emit light to the outside efficiently prevent loss of light due to the Turkey be leaked to the outside through the bottom of the insulating base, and those thin. In addition, it is possible to prevent light from being mixed between adjacent light emitting devices.
[0052]
In the light emitting element storage package of the present invention, since the plate member is made of an insulator and the conductor layer is formed on substantially the entire lower surface, it is reliably bonded to the external electric circuit board at the portion of the conductor layer. At the same time, the bonding area increases and it becomes possible to connect firmly, and the heat dissipation is improved by increasing the bonding area with the external electric circuit board.
[0053]
A light-emitting device of the present invention covers a light-emitting element storage package of the present invention, a light-emitting element mounted on a mounting portion conductor layer and electrically connected to a wiring conductor around the mounting portion conductor layer, and covering the light emitting element By providing the transparent resin, the light emission efficiency is high, the color mixing of light between adjacent light emitting devices can be prevented, and the thickness is reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of an embodiment of a light-emitting element storage package according to the present invention.
2 is a bottom view of the light emitting element storage package of FIG. 1; FIG.
FIG. 3 is a cross-sectional view showing another example of the embodiment of the light emitting element storage package of the present invention.
4 is a bottom view of the light emitting element storage package of FIG. 3. FIG.
FIG. 5 is a cross-sectional view showing another example of the embodiment of the light emitting element storage package of the present invention.
6 shows another example of the embodiment of the light emitting element storage package of FIG. 5, and (a) and (b) are bottom views of the light emitting element storage package, respectively.
FIG. 7 is a cross-sectional view showing another example of the embodiment of the light emitting element storage package of the present invention.
8 is a bottom view of the light emitting element storage package of FIG. 7. FIG.
FIG. 9 is a cross-sectional view of a conventional light emitting element storage package.
10 is a bottom view of the light emitting element storage package of FIG. 9. FIG.
[Explanation of symbols]
1: Insulating substrate 2: Mounted portion conductor layer 3: Light emitting element 4: Concave portions 5a, 5b: Wiring layers 8a, 8b: External terminal conductor layer 9: Plate member 9a: Convex portion
10: Conductor layer

Claims

A recess for accommodating the light emitting element is provided on the top surface of the insulating base, and a mounting portion conductor layer on which the light emitting element is mounted and a wiring layer to which the light emitting element is electrically connected are formed on the bottom surface of the recess. And a package for light-emitting element storage, in which two external terminal conductor layers electrically connected to the wiring layer and the mounting portion conductor layer are formed at both ends of the lower surface of the insulating base, A plate member made of an insulator and having a conductor layer formed on substantially the entire bottom surface is joined between the external terminal conductor layers on the bottom surface of the base body so as to overlap the exposed area of the bottom surface of the recess. A package for housing a light emitting element.

Comprising a light-emitting element storing package according to claim 1 Symbol mounting a light emitting element having electrodes electrically connected to the wiring layer while being mounted on the mounting portion conductive layer and a transparent resin covering the light emitting element A light emitting device characterized by comprising: