JP4196439B2 - Semiconductor light emitting device and manufacturing method thereof - Google Patents

Description

【００３３】
また、同様に、吸収部１５をニッケルにより構成した場合を表２に、吸収部を白金により構成した場合を表３に、吸収部１５をアルミニウムにより構成した場合を表４に、吸収部１５をアモルファスシリコンにより構成した場合を表５に、吸収部１５をＺｎＳにより構成した場合を表６にそれぞれ示す。
【００３４】
【表２】

【００３５】
【表３】

【００３６】
【表４】

【００３７】
【表５】

【００３８】
【表６】

【００３９】
表１乃至表６に示したように、κおよび吸収係数αが正の値である場合にはその波長λの光を吸収することから、これらにより吸収部１５を構成すれば、これらの波長を有する光を吸収部１５において吸収できることが分かる。また、吸収部１５をこれらの金属またはシリコンにより構成すれば、数ｎｍ〜十数ｎｍ程度の厚さｄでこれらの波長を有する光を十分に吸収できることが分かる。
【００４０】
この半導体レーザ１０は、更に、図１においては図示しないが図２に示したように、ｐ側電極１４の長さ方向の端部に一対の反射鏡膜１６，１７がそれぞれ形成されている。各反射鏡膜１６，１７は、例えば、二酸化ケイ素（ＳｉＯ₂ ）膜と酸化ジルコニウム（ＺｒＯ）膜とを交互に積層してそれぞれ構成されており、反射鏡膜１６の反射率は低くなるように、反射鏡膜１７の反射率は高くなるようにそれぞれ調整されている。これにより、活性層２６において発生した光は一対の反射鏡膜の間を往復して増幅され、反射鏡膜１６からレーザビームとして射出されるようになっている。すなわち、ｐ側電極１４の長さ方向が共振器方向となっている。
【００４１】
このような構成を有する半導体レーザ１０は、次のようにして製造することができる。
【００４２】
図３および図５はその各製造工程を表すものである。なお、図３および図４は図１と同一方向（ｐ側電極１４の延長方向に対して垂直な方向）における断面図であり、図５は吸収部１５の側から見た図である。まず、図３（Ａ）に示したように、例えば、複数の半導体レーザ形成領域を有するサファイアよりなる基板１１を用意し、ＭＯＣＶＤ法により、基板１１の一面（Ｃ面）にundope−ＧａＮよりなるバッファ層２１を形成する。その際、例えば、基板１１の温度は５２０℃と低くし、非晶質に近い結晶層を成長させる。また、原料にはトリメチルガリウム（（ＣＨ₃ ）₃ Ｇａ）とアンモニア（ＮＨ₃ ）を用いる。なお、図３および図４においては、１つの半導体レーザ形成領域のみを代表して表している。
【００４３】
次いで、同じく図３（Ａ）に示したように、バッファ層２１の上に、例えば、ＭＯＣＶＤ法により、バッファ層２１と同様にしてundope−ＧａＮよりなる下地層２２を形成する。但し、基板１１の温度は例えばバッファ層２１を成長させる場合よりも高温の例えば１０２０℃とし、結晶層を成長させる。
【００４４】
続いて、図３（Ｂ）に示したように、下地層２２の上に、例えば、ＣＶＤ（Chemical Vapor Deposition ）法により、二酸化ケイ素よりなり帯状に延長された複数のマスク部２３ｂを有するマスク層２３を選択的に形成する。そののち、同じく図３（Ｂ）に示したように、マスク層２３の上に、例えば、ＭＯＣＶＤ法により、下地層２２と同様にしてundope−ＧａＮよりなる被覆成長層２４を横方向に成長させる。
【００４５】
被覆成長層２４を形成したのち、図３（Ｃ）に示したように、その上に、例えば、ＭＯＣＶＤ法により、ｎ型ＧａＮよりなるｎ側コンタクト層２５ａ，ｎ型Ａｌ_0.1 Ｇａ_0.9 Ｎ混晶よりなるｎ型クラッド層２５ｂ，ｎ型ＧａＮよりなる第１のガイド層２５ｃ，undope−ＧａＩｎＮ混晶よりなる活性層２６，ｐ型Ａｌ_0.2 Ｇａ_0.8 Ｎ混晶よりなる劣化防止層２７ａ，ｐ型ＧａＮよりなる第２のガイド層２７ｂ，ｐ型Ａｌ_0.1 Ｇａ_0.9 Ｎ混晶よりなるｐ型クラッド層２７ｃおよびｐ型ＧａＮよりなるｐ側コンタクト層２７ｄを順次成長させる。
【００４６】
その際、例えば、基板１１の温度は８００〜１０００℃とし、アルミニウムの原料としてはトリメチルアルミニウム（（ＣＨ₃ ）₃ Ａｌ）、ガリウムの原料としてはトリメチルガリウム、インジウムの原料としてはトリメチルインジウム（（ＣＨ₃ ）₃ Ｉｎ）および窒素の原料ガスとしてはアンモニアガスをそれぞれ用いる。また、ｎ型不純物としてケイ素を添加する場合には、ケイ素の原料ガスとしてモノシランガス（ＳｉＨ₄ ）を用い、ｐ型不純物としてマグネシウムを添加する場合には、マグネシウムの原料としてビス＝メチルシクロペンタジエニルマグネシウム（（ＣＨ₃ Ｃ₅ Ｈ₄ ）₂ Ｍｇ）あるいはビス＝シクロペンタジエニルマグネシウム（（Ｃ₅ Ｈ₅ ）₂ Ｍｇ）をそれぞれ用いる。
【００４７】
ｎ側コンタクト層２５ａからｐ側コンタクト層２７ｄまでの各層を成長させたのち、図４（Ａ）に示したように、ｐ側コンタクト層２７ｄの上に、例えば、ＣＶＤ法により二酸化ケイ素などの絶縁体よりなる絶縁層１３を形成する。絶縁層１３を形成したのち、リソグラフィ技術を用い、ｎ側電極１２の形成位置に対応してｐ側コンタクト層２７ｄ，ｐ型クラッド層２７ｃ，第２のガイド層２７ｂ，劣化防止層２７ａ，活性層２６，第１のガイド層２５ｃおよびｎ型クラッド層２５ｂを順次選択的に除去し、ｎ側コンタクト層２５ａを露出させる。すなわち、構造部２０の第１面２０ａを露出させる。
【００４８】
ｎ側コンタクト層２５ａを露出させたのち、図４（Ｂ）に示したように、全面（すなわち絶縁層１３およびｎ側コンタクト層２５ａの上）に、図示しないレジスト膜を塗布形成し、フォトリソグラフィによってｎ側電極１２の形成位置に対応したマスクパターンを形成する。そののち、全面（すなわちｎ側コンタクト層２５ａおよび図示しないレジスト膜の上）に、例えば、真空蒸着法によりチタン層，アルミニウム層および金層を選択的に順次蒸着し、図示しないレジスト膜をその上に蒸着された各金属層と共に除去して（リフトオフ）、ｎ側電極１２を形成する。
【００４９】
ｎ側電極５を形成したのち、同じく図４（Ｂ）に示したように、全面（すなわち絶縁層１３，ｎ側コンタクト層２５ａおよびｎ側電極１２の上）に、図示しないレジスト膜を塗布形成し、フォトリソグラフィによってｐ側電極１４の形成位置に対応したマスクパターンを形成する。そののち、これをマスクとしてエッチングを行い、絶縁層１３を選択的に除去してｐ側電極１４の形成位置に対応した開口１３ａを形成し、ｐ側コンタクト層２７ｄを露出させる。すなわち、構造部２０の第２面を露出させる。ｐ側コンタクト層２７ｄを露出させたのち、全面（すなわちｐ側コンタクト層２７ｄおよび図示しないレジスト膜の上）に、例えば、真空蒸着法によりニッケル層および金層を順次蒸着し、図示しないレジスト膜をその上に蒸着された各金属層と共に除去して（リフトオフ）、ｐ側電極１４を形成する。そののち、加熱処理を行い、ｐ側電極１４およびｎ側電極１２を合金化させる。
【００５０】
加熱処理を行ったのち、図５に示したように、基板１１の他面に、図示しないレジスト膜を塗布形成し、フォトリソグラフィによって吸収部１５の形成位置に対応したマスクパターンを形成する。そののち、全面（すなわち基板１１および図示しないレジスト膜の上）に、例えば、真空蒸着法により金層，白金層，ニッケル層あるいはアルミニウム層などの金属層を蒸着し、図示しないレジスト膜をその上に蒸着された金属層と共に除去して（リフトオフ）、吸収部１５を形成する。なお、図５においては複数の半導体レーザ形成領域１０ａを表しており、破線により囲まれた領域が各半導体レーザ形成領域１０ａに該当している。
【００５１】
なお、吸収部１５をアモルファスシリコンあるいはＺｎＳなどの半導体により構成する場合には、基板１１の他面に、例えば、ＣＶＤ法，分子線エピタキシー（Molecular Beam Epitaxy；ＭＢＥ）法あるいはＭＯＣＶＤ（Metal Organic Chemical Vapor Deposition ）法により誘電体層を形成したのち、リソグラフィ技術を用い、吸収部形成領域に対応してその誘電体層を選択的に除去して、吸収部１５を形成する。
【００５２】
吸収部１５を形成したのち、ここでは図示しないが、基板１１を各半導体レーザ形成領域１０ａに対応させてｐ側電極１４の長さ方向に対して垂直に所定の幅で分割する。そののち、分割した一対の側面に、例えばＥ−ガン蒸着法、ＣＶＤ法により一対の反射鏡膜１６，１７をそれぞれ形成する。各反射鏡膜１６，１７を形成したのち、基板１１を各半導体レーザ形成領域１０ａに対応させてｐ側電極１４の長さ方向と平行に所定の幅で分割する。なお、これら分割工程においては、図５に示したように、吸収部１５を各半導体レーザ形成領域１０ａの周縁部に形成しない方が、吸収部１５が妨げとならずに容易に分割することができるので好ましい。これにより、図１に示した半導体レーザ１０が形成される。
【００５３】
このようにして製造した半導体レーザ１０は、次のようにパッケージに収納されて用いられる。
【００５４】
図６乃至図８はパッケージ３０の構成およびこのパッケージ３０に収納された半導体レーザ１０の状態を表すものである。なお、図８は図７におけるＩ−Ｉ線に沿った断面図である。まず、この半導体レーザ１０は、図６に示したように、配設基板３１にｎ側電極１２およびｐ側電極１４を対向させて配設される。この配設基板３１は、例えば、窒化アルミニウム（ＡｌＮ）などの絶縁体よりなり、半導体レーザ１０が配設される側の面には、ｎ側電極１２を接続する配線３２と、ｐ側電極１４を接続する配線３３とがそれぞれ設けられている。各配線３２，３３は、例えば、金などの金属により構成されている。配線３２の配設基板３１と反対側にはｎ側電極１２と対応した位置に半田層３２ａが形成されており、配線３３の配設基板３１と反対側にはｐ側電極１４と対応した位置に半田層３３ａが形成されている。すなわち、半導体レーザ１０のｎ側電極１２は半田層３２ａを介して配線３２と電気的に接続され、ｐ側電極１４は半田層３３ａを介して配線３３と電気的に接続される。
【００５５】
次いで、図７および図８に示したように、配設基板３１に配設された半導体レーザ１０は、パッケージ３０の内部に収納される。このパッケージ３０は、例えば、円盤状の支持体３４と中空円筒状の蓋体３５とを有している。蓋体３５は、その一端部が開放された状態、他端部が閉鎖された状態となっており、開放端部が支持体３４の一面に対して配設されている。蓋体３５の内部には、載置台３６が支持体３４の一面に対して形成されており、半導体レーザ１０はこの載置台３６に配設基板３１を介して載置される。また、蓋体３５の閉鎖端部には、半導体レーザ１０に対応して、半導体レーザ１０から射出されたレーザビームをパッケージ３０の外部に取り出すための取り出し窓３５ａが設けられている。
【００５６】
載置台３６および支持体３４は、例えば、金属などの導電体により構成されており、支持体３４に設けられたピン３７を介して外部配線と電気的に接続されるようになっている。また、支持体３４には、支持体３４とは絶縁性が確保されたピン３８が内部から外部に向かって貫通されており、ピン３８を介しても外部配線と電気的に接続することができるようになっている。すなわち、半導体レーザ１０は、配設基板３１の配線３２とピン３８とがワイヤで接続されると共に、配線３３と載置台３６とがワイヤで接続されることにより、外部配線と電気的に接続される。
【００５７】
このようにしてパッケージ３０に収納された半導体レーザ１０は、次のように作用する。
【００５８】
この半導体レーザ１０では、パッケージ３０のピン３７およびピン３８を介して、半導体レーザ１０のｎ側電極１２とｐ側電極１４との間に所定の電圧が印加されると、活性層２６に電流が注入され、電子−正孔再結合により発光が起こる。この光は、一対の反射鏡膜１６，１７の間を往復して増幅され、反射鏡膜１６からレーザビームとして射出される。この半導体レーザ１０から射出されたレーザビームの一部は、パッケージ３０の取り出し窓３５ａを介してパッケージ３０の外部に取り出される。
【００５９】
また、半導体レーザ１０から射出されたレーザビームの他の一部は、図９に太実線の矢印で示したように、パッケージ３０の内壁または取り出し窓３５ａにおいて反射し、迷光となって、その一部は半導体レーザ１０に戻ってくる。更に、半導体レーザ１０の反射鏡膜１７からもわずかながらレーザビームが射出されており、図９において細実線の矢印で示したように、パッケージ３０の内壁において反射し、迷光となって、その一部は半導体レーザ１０に戻ってくる。半導体レーザ１０に戻ってきた迷光は、半導体レーザ１０の表面において一部が再反射光となり、一部が侵入光となる。
【００６０】
ここで、本実施の形態に係る半導体レーザ１０では、基板１１の他面に吸収部１５を備えているので、半導体レーザ１０に侵入した迷光の一部は吸収部１５に到達し、吸収部１５において一部が吸収され、一部は図９において破線の矢印で示したように透過する。すなわち、吸収部１５を透過する迷光の透過光強度は、侵入光強度よりも吸収部１５において吸収された分だけ小さくなる。よって、パッケージ３０内における迷光は低減され、取り出し窓３５ａから取り出される迷光も低減される。また、半導体レーザ１０においても活性層２６に到達する迷光が低減され、半導体レーザ１０の動特性は安定し、レーザノイズが低減する。
【００６１】
このように本実施の形態に係る半導体レーザ１０によれば、基板１１の他面（構造部２０の第３面２０ｃ側）に吸収部１５を備えるようにしたので、パッケージ３０に収納して用いても、迷光を吸収部１５により吸収することができる。よって、パッケージ３０内の迷光を低減することができ、取り出し窓３５ａから取り出される迷光も低減することができる。従って、この半導体レーザ１０を用いた装置の誤動作を防止することができる。また、半導体レーザ１０においても、活性層２６に到達する迷光を低減することができ、半導体レーザ１０の動特性を安定させることができると共に、レーザノイズを低減することができる。
【００６２】
また、本実施の形態に係る半導体レーザの製造方法によれば、基板１１の他面（構造部２０の第３面２０ｃ側）に吸収部１５を形成するようにしたので、本実施の形態に係る半導体レーザ１０を容易に製造することができる。
【００６３】
（第２の実施の形態）
図１０は本発明の第２の実施の形態に係る半導体レーザ４０を基板１１側から見て表すものである。この半導体レーザ４０は、吸収部４５の形状が異なることを除き、第１の実施の形態と同一の構成および作用を有している。また、第１の実施の形態と同様にして製造することができる。よって、ここでは、同一の構成要素には同一の符号を付し、その詳細な説明を省略する。
【００６４】
吸収部４５は、四角形の四隅にマーク部４５ａとしての切欠部が形成された１２角形状となっている。このマーク部４５ａは、第１の実施の形態において説明したように半導体レーザ４０を配設基板３１に配設する際、または半導体レーザ４０をパッケージ３０の載置台３６に載置する際に、半導体レーザ４０の位置を決めるための印として用いられる。これは、基板１１が発光波長以下の波長を有する光を吸収しないサファイアにより構成されているのに対して、吸収部４５はそれらの光を吸収する材料により構成されていることを利用したものであり、この半導体レーザ４０は、マーク部４５ａを画像処理などで識別することにより位置決めすることができるようになっている。
【００６５】
このように本実施の形態によれば、吸収部４５がマーク部４５ａを有するようにしたので、第１の実施の形態において説明した効果に加えて、半導体レーザ４０を配設基板３１に配設する際、あるいは半導体レーザ４０をパッケージ３０の載置台３６に載置する際などに、画像処理などを利用することにより容易にその位置決めを行うことができる。よって、タクトを短縮することができると共に、位置合わせの精度を高めることができ、歩留りを向上させることができる。
【００６６】
なお、本実施の形態では、吸収部４５を１２角形状とすることにより切欠部よりなるマーク部４５ａを形成するようにしたが、図１１に示した半導体レーザ５０のように、吸収部５５が複数の吸収領域５５ｂを有するように構成し、各吸収領域５５ｂの間の領域をマーク部５５ａとするようにしてもよい。すなわち、ここにおいてマーク部４５ａ，５５ａとは、吸収部４５，５５の位置を示すことができる特徴部分を言う。
【００６７】
（第３の実施の形態）
図１２は本発明の第３の実施の形態に係る半導体レーザ６０を基板１１側から見て表すものである。この半導体レーザ６０は、吸収部６５の形状が異なることを除き、第１の実施の形態と同一の構成および作用を有している。また、第１の実施の形態と同様にして製造することができる。よって、ここでは、同一の構成要素には同一の符号を付し、その詳細な説明を省略する。
【００６８】
吸収部６５は、共振器方向Ａ（ｐ側電極１４の延長方向）において発光波長の１／２の整数倍の長さと同一のピッチ幅Ｂで配列された複数の吸収領域６５ｂを有している。ピッチ幅Ｂというのは、図１２においても示したように、１つの吸収領域６５ｂの幅Ｃと、それに隣接する吸収領域６５ｂとの間の幅Ｄとを合わせた幅のことである。
【００６９】
このように本実施の形態によれば、吸収部６５が、共振器方向Ａにおいて発光波長の１／２の整数倍の長さと同一のピッチ幅Ｂで配列された複数の吸収領域６５ｂを有するようにしたので、第１の実施の形態において説明した効果に加えて、ＤＦＢ（Distributed Feedback）と同様の効果を得ることができる。よって、縦モードの選択性を高めることができる（Casey and Panish ; "Heterostructure Lasers" Chap. 7 Academic Pressを参照）。
【００７０】
（第４の実施の形態）
図１３は本発明の第４の実施の形態に係る半導体レーザ７０を表すものである。この半導体レーザ７０は、吸収部１５が除去され、基板７１が吸収部としての機能を有することを除き、第１の実施の形態と同一の構成および作用を有している。また、第１の実施の形態と同様にして製造することができる。よって、ここでは、同一の構成要素には同一の符号を付し、その詳細な説明を省略する。
【００７１】
基板７１は、例えば、Ｆｅ，Ｃｕなどを不純物として侵入させあるいは添加したサファイアにより構成されており、構造部２０における発光波長以下の波長を有する光を吸収することができるようになっている。よって、本実施の形態によれば、第１の実施の形態と同一の効果を得ることができる。
【００７２】
以上、各実施の形態を挙げて本発明を説明したが、本発明は上記各実施の形態に限定されるものではなく、種々の変形が可能である。例えば、上記第１乃至第３の各実施の形態においては、吸収部１５，４５，５５，６５を構成する材料について具体的な例を挙げて説明したが、発光波長以下の波長を有する光を吸収することができればどのような材料を用いてもよく、亜鉛（Ｚｎ）あるいは鉛（Ｐｂ）などの他の金属、またはそれらの合金、または混晶の半導体、または酸化物あるいは窒化物などの化合物を用いることもできる。また、上記部第１乃至第３の各実施の形態においては、吸収部１５，４５，５５，６５を単層により構成するようにしたが、積層された複数の層により構成するようにしてもよい。
【００７３】
更に、上記第１乃至第３の各実施の形態においては、吸収部１５，４５，５５，６５の形状について具体的な例を挙げて説明したが、吸収部は他の形状を有していてもよい。例えば、図１４に示したように、吸収部８５を異なった形状を有する複数の吸収領域８５ｂにより構成するようにしてもよく、図１５に示したように、吸収部９５が吸収領域９５ｂを基板１１の他面全体にわたって有するのではなく、一部においてのみ有するようにしてもよい。
【００７４】
加えて、上記第１乃至第３の各実施の形態においては、吸収部１５，４５，５５，６５を基板１１の他面（構造部２０の第３面２０ｃ側）に形成する場合について説明したが、これらに加え、構造部２０の積層方向に対して垂直な方向に位置する側面側（すなわち構造部２０の側面および基板１１の側面）の少なくとも一部にも吸収部を設けるようにしてもよい。また、これらに代えて、構造部２０の側面側の少なくとも一部にのみ吸収部を設けるようにしてもよい。但し、側面から光が射出されるような場合には、光が射出する領域には吸収部を設けないようにする必要がある。また、吸収部を構造部２０の側面側に設けた場合には、吸収部の厚さは、構造部２０の積層方向において垂直な方向の厚さとなる。
【００７５】
更にまた、上記各実施の形態においては、構造部２０を構成するＩＩＩ族ナイトライド化合物半導体について具体的な例を挙げて説明したが、本発明は、他の適宜なＩＩＩ族ナイトライド化合物半導体（すなわち、ガリウム（Ｇａ），アルミニウム（Ａｌ），ホウ素（Ｂ）およびインジウム（Ｉｎ）からなる群より選ばれた少なくとも１種のＩＩＩ族元素と、窒素（Ｎ）とを含むＩＩＩ族ナイトライド化合物半導体）により構造部２０を構成するようにしてもよい。
【００７６】
加えてまた、上記各実施の形態においては、構造部２０をＩＩＩ族ナイトライド化合物半導体について構成する場合について説明したが、本発明は、構造部が他の半導体により構成される場合であっても、第１の電極および第２の電極が共に構造部２０の積層方向の一方側に位置する半導体発光素子について広く適用することができる。また、基板１１が発光波長以下の波長を有する光を吸収しない材料により構成される半導体発光素子についても広く適用することができる。
【００７７】
更にまた、上記各実施の形態においては、第１導電型半導体層２５をｎ型半導体層により構成し、第２導電型半導体層２７をｐ型半導体層により構成する場合について説明したが、本発明は、第１導電型半導体層２５をｐ型半導体層により構成し、第２導電型半導体層２７をｎ型半導体層により構成する場合についても広く適用することができる。
【００７８】
加えてまた、上記各実施の形態においては、半導体レーザの構成について具体的に説明したが、本発明は、他の構成を有するものであっても、順次積層された第１導電型半導体層，活性層および第２導電型半導体層を有する構造部を備えた半導体発光素子について広く適用することができる。例えば、劣化防止層２７ａを備えなくてもよく、ｐ側電極１４を帯状とするのではなく他の方法により電流狭窄をするようにしてもよい。
【００７９】
更にまた、上記各実施の形態においては、半導体レーザについてのみ説明したが、本発明は、発光ダイオードなどの他の半導体発光素子についても同様に適用することができる。
【００８０】
加えてまた、上記各実施の形態においては、構造部２０ををＭＯＣＶＤ法により形成する場合について説明したが、ＭＢＥ法やハライド法などの他の気相成長法により形成するようにしてもよい。なお、ハライド気相成長法とは、ハロゲンが輸送もしくは反応に寄与する気相成長法のことであり、ハイドライド気相成長法とも言う。
【００８１】
【発明の効果】
以上説明したように請求項１乃至５のいずれか１に記載の半導体発光素子によれば、基板の裏面に、発光波長以下の波長を有する光を吸収する吸収部を備えるようにしたので、例えば、この半導体発光素子をパッケージに収納して用いても、迷光を吸収部により吸収することができる。よって、パッケージから外部に取り出される迷光を低減することができ、半導体発光素子を用いた装置の誤動作を防止することができるという効果を奏する。また、半導体発光素子の活性層に到達する迷光も低減することができ、半導体発光素子の動特性を安定させることができると共に、ノイズを低減することができるという効果も奏する。
【００８４】
更に、請求項６乃至９のいずれか１に記載の半導体発光素子の製造方法によれば、本発明の半導体発光素子を容易に製造することができ、本発明の半導体発光素子を容易に実現することができるという効果を奏する。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態に係る半導体レーザの構成を表す断面図である。
【図２】図１に示した半導体レーザを吸収部の側から見た図である。
【図３】図１に示した半導体レーザの各製造工程を表す断面図である。
【図４】図３に続く各製造工程を表す断面図である。
【図５】図４に続く製造工程を表す図である。
【図６】図１に示した半導体レーザが用いられる際の状態を表す図である。
【図７】図１に示した半導体レーザが用いられる際の状態を表す図である。
【図８】図７におけるＩ−Ｉ線に沿った断面図である。
【図９】図１に示した半導体レーザの作用を説明するための図７におけるＩ−Ｉ線に沿った断面図である。
【図１０】本発明の第２の実施の形態に係る半導体レーザを表す図である。
【図１１】図１０に示した半導体レーザの変形例を表す図である。
【図１２】本発明の第３の実施の形態に係る半導体レーザを表す図である。
【図１３】本発明の第４の実施の形態に係る半導体レーザの構成を表す断面図である。
【図１４】本発明に係る半導体発光素子の変形例を表す図である。
【図１５】本発明に係る半導体発光素子の他の変形例を表す図である。
【図１６】従来の半導体発光素子の用いられる際の状態を表す断面図である。
【図１７】従来の他の半導体発光素子の用いられる際の状態を表す断面図である。
【図１８】半導体発光素子とコリメータレンズとからなる光学系を表す図である。
【図１９】従来の半導体発光素子の問題点を説明するための断面図である。
【図２０】物質に光が入射した場合における反射と透過と吸収との関係を説明するための図である。
【符号の説明】
１０，４０，５０，６０，７０…半導体レーザ（半導体発光素子）、１０ａ…半導体レーザ形成領域、１１，７１，２１１…基板、１２…ｎ側電極、１３…絶縁層、１３ａ…開口、１４…ｐ側電極、１５，４５，５５，６５，８５，９５…吸収部、２０…構造部、２０ａ…第１面、２０ｂ…第２面、２０ｃ…第３面、２１…バッファ層、２２…下地層、２３…マスク層、２４…被覆成長層、２５…第１導電型半導体層、２５ａ…ｎ側コンタクト層、２５ｂ…ｎ型クラッド層、２５ｃ…第１のガイド層、２６…活性層、２７…第２導電型半導体層、２７ａ…劣化防止層、２７ｂ…第２のガイド層、２７ｃ…ｐ型クラッド層、２７ｄ…ｐ側コンタクト層、３０，１３０，２３０…パッケージ、３１…配設基板、３２，３３…配線、３２ａ，３３ａ…半田層、３４，１３４…支持体、３５，１３５…蓋体、３５ａ，１３５ａ，２３５ａ…取り出し窓、３６，１３６，２３６…載置台、３７，３８…ピン、３９…ワイヤ、１１０，２１０…半導体発光素子、３００…コリメータレンズ、Ａ…共振器方向、Ｍ…物質、Ｌ１…入射光、Ｌ２…反射光、Ｌ３…透過光[0001]
BACKGROUND OF THE INVENTION
In the present invention, the first electrode and the second electrode are provided on one side in the stacking direction with respect to the structure portion having the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer that are sequentially stacked. The present invention relates to a semiconductor light-emitting device or a semiconductor light-emitting device laminated on a substrate made of a material that does not absorb light having a wavelength equal to or shorter than the emission wavelength, and a method for manufacturing the same.
[0002]
[Prior art]
In recent years, semiconductor light emitting devices such as a semiconductor laser (laser diode; LD) or a light emitting diode (LED) formed by laminating a group III nitride compound semiconductor layer such as an AlGaInN layer on a substrate have been developed from the visible region to the ultraviolet region. Research and development is actively conducted because light emission up to the region can be obtained. In particular, in the field of optical recording, there is a demand for practical use of a semiconductor laser that can obtain light in a short wavelength region in order to improve the recording density of an optical disk or the like.
[0003]
Such a semiconductor light emitting element is normally used by being housed in a package 130 as shown in FIG. The package 130 includes, for example, a lid 135 provided with an extraction window 135a for extracting light to the outside, and a support 134 that supports the lid 135, and is supported by the support 134 inside. A mounting table 136 for the semiconductor light emitting device 110 is provided. However, when such a package 130 is used, there is a problem that reflected light (so-called stray light) is generated on the inner wall of the package 130 and the extraction window 135a. A part of this stray light is emitted to the outside from the extraction window 135a, and causes, for example, an erroneous signal in writing to and reading from the optical recording medium.
[0004]
Therefore, in an AlGaAs semiconductor light emitting device or an AlGaInP semiconductor light emitting device, stray light is not emitted by providing an angle on the inner wall of the package 230 as shown in FIG. This will be specifically described with reference to an example of a simple optical system including a semiconductor light emitting element 210 and a collimator lens 300 housed in a package 230 as shown in FIG.
[0005]
In this optical system, only light that passes through the collimator lens 300 is used as a signal. Since the light passing through the collimator lens 300 always passes through the extraction window 235a of the package 230, the light always passes through the region z between the extended lines connecting x and x and y and y shown by shading in FIG. Will exist. Therefore, if stray light is present in this region z, a practical inconvenience occurs. Therefore, in an AlGaAs-based semiconductor light emitting device or the like, as shown in FIG. 17, stray light reflected from the semiconductor light emitting device 210 to the mounting table 236 side is inclined to the side surface of the mounting table 236, thereby causing a region z. The stray light reflected to the semiconductor light emitting element 210 side from the mounting table 236 is reflected toward the substrate 211 of the semiconductor light emitting element 210 so as not to return to the region z.
[0006]
As described above, the stray light can be prevented from returning into the region z by reflecting the semiconductor light-emitting element 210 toward the substrate 211. In the AlGaAs-based semiconductor light-emitting element 210 and the like, GaAs is usually used for the substrate 211. This is because the substrate 211 can absorb light having a wavelength shorter than the emission wavelength. That is, the stray light in the package 230 can be reduced by positively reflecting the stray light on the substrate.
[0007]
[Problems to be solved by the invention]
However, in a semiconductor light emitting device using a group III nitride compound semiconductor, sapphire that does not absorb light having a wavelength equal to or shorter than the emission wavelength is generally used for the substrate, and stray light cannot be absorbed by the substrate. In general, the material constituting the substrate is generally selected depending on the relationship with the lattice constant of the semiconductor layer grown on the substrate and whether a good semiconductor layer can be grown. This is because it is not selected based on whether or not light having a wavelength can be absorbed. Accordingly, in the semiconductor light emitting device using the conventional group III nitride compound semiconductor, as shown in FIG. 19, the stray light reflected on the semiconductor light emitting device 110 is not absorbed by the substrate of the semiconductor light emitting device 110. There is a problem that there is a high possibility of being ejected from the take-out window 135a to the outside.
[0008]
In general, as shown in FIG. 20, when the light hits the substance M, the energy of the incident light L1 is distributed to three energies of reflected light L2, transmitted light L3, and absorption. This can be expressed as shown in Equation 1 (see Koji Kushida, “Photophysics”, Chapter 5, published by Kyoritsu Shuppansha).
[Formula 1]
Incident light intensity = re-reflected light intensity + transmitted light intensity + absorption
This is due to the inherent properties of the substance. Absence of absorption means that energy is distributed to the two components of reflection and transmission, so that their energy or intensity increases compared to the case where there is absorption. It is understood qualitatively.
[0009]
The present invention has been made in view of such problems, and an object of the present invention is to provide a semiconductor light emitting device capable of reducing stray light and a method for manufacturing the same.
[0010]
[Means for Solving the Problems]
  A semiconductor light emitting device according to the present invention is housed in a package having a window, and includes a substrate and a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer sequentially stacked on the substrate. A plurality of side surfaces positioned in a direction perpendicular to the stacking direction, a first surface formed of a first conductive semiconductor layer positioned in one of the stacking directions, and a second conductive type positioned in one of the stacking directions. A second surface made of a semiconductor layer and a pair of reflecting mirror films constituting a resonator structure on two opposing surfaces of the plurality of side surfaces, and the light generated in the active layer A structure portion that emits toward the window portion of the package; a first electrode provided on the first surface of the structure portion; a second electrode provided on the second surface of the structure portion;Back side of substrateAn absorption part that absorbs light having a wavelength equal to or shorter than the emission wavelength in the structure part;The absorption part has a plurality of absorption regions, and the plurality of absorption regions are arranged with the same pitch width as the length of an integral multiple of ½ of the emission wavelength along the resonator direction. Has been.
[0011]
  Another semiconductor light emitting device according to the present invention is housed in a package having a window, and includes a first conductive type semiconductor layer, an active layer, and a second conductive type semiconductor layer, which are sequentially stacked. A plurality of side surfaces positioned in a direction perpendicular to the direction, and a pair of reflecting mirror films constituting a resonator structure on two opposing surfaces of the plurality of side surfaces, and generating light generated in the active layer The structure part is emitted from one side of the reflective film toward the window part of the package, and the structure part is stacked on one surface of a pair of opposed surfaces, and the side surface positioned in a direction perpendicular to the stacking direction of the structure part And a substrate made of a material that does not absorb light having a wavelength equal to or shorter than the emission wavelength in the structure portion,On the faceAn absorbing portion that is provided and absorbs light having a wavelength equal to or shorter than the emission wavelength in the structure portion;The absorption part has a plurality of absorption regions, and the plurality of absorption regions are arranged with the same pitch width as the length of an integral multiple of ½ of the emission wavelength along the resonator direction. Has been.
[0012]
  A method of manufacturing a semiconductor device according to the present invention includes a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer sequentially stacked on a substrate, and a plurality of side surfaces positioned in a direction perpendicular to the stacking direction. Each having a first surface made of the first conductivity type semiconductor layer located on one side in the stacking direction and a second surface made of the second conductivity type semiconductor layer located on one side in the stacking direction, Forming a structure part having a pair of reflecting mirror films constituting a resonator structure on two opposite surfaces, and emitting light generated in the active layer from one of the reflection films; and on the first surface of the structure part Forming a first electrode; forming a second electrode on the second surface of the structure; andBack side of substrateForming an absorption part that absorbs light having a wavelength equal to or shorter than the emission wavelength in the structure part;And a plurality of absorption regions arranged with the same pitch width as an integral multiple of 1/2 of the emission wavelength along the resonator direction.Is.
[0013]
  According to another aspect of the present invention, there is provided a method for manufacturing a semiconductor light emitting device, which includes a pair of opposing surfaces and a side surface connecting the pair of surfaces, and is made of a material that does not absorb light having a wavelength equal to or shorter than the emission wavelength in the structure portion. The first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer are sequentially stacked on one of the pair of surfaces of the substrate, and have a plurality of side surfaces positioned in a direction perpendicular to the stacking direction. Forming a structure part having a pair of reflecting mirror films constituting a resonator structure on two opposing faces of the plurality of side faces, and emitting light generated in the active layer from one of the reflecting films; Other than one side of the boardOn the faceForming an absorption part that absorbs light having a wavelength equal to or less than the emission wavelength in the structure part;Including,A plurality of absorption regions arranged with the same pitch width as an integral multiple of 1/2 of the emission wavelength are formed along the resonator direction as the absorber.Is.
[0014]
  In the semiconductor light emitting device according to the present invention, when a voltage is applied between the first electrode and the second electrode, a voltage is applied between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer, Light is emitted by injecting current into the active layer. here,Back side of substrateTherefore, even if the semiconductor light emitting element is housed in a package and used, stray light is absorbed by the absorber.
[0015]
  In another semiconductor light emitting device according to the present invention, when a voltage is applied between the first conductive type semiconductor layer and the second conductive type semiconductor layer, current is injected into the active layer and light emission occurs. Here, in addition to the substrateOn the faceSince the absorption part is provided, for example, even if this semiconductor light emitting element is housed in a package and used, stray light is absorbed by the absorption part.
[0016]
  In the method of manufacturing a semiconductor device according to the present invention, the structure portion is formed by sequentially laminating the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer. A first electrode is formed on the first surface of the structure portion, and a second electrode is formed on the second surface of the structure portion. Also,Back side of substrateAn absorption part is formed in the.
[0017]
  In another method of manufacturing a semiconductor light emitting device according to the present invention, a structure portion is formed by sequentially laminating a first conductive semiconductor layer, an active layer, and a second conductive semiconductor layer on one surface of a substrate. Also other than the substrateOn the faceAn absorption part is formed.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0019]
(First embodiment)
FIG. 1 shows a configuration of a semiconductor laser 10 which is a semiconductor light emitting device according to a first embodiment of the present invention. In this semiconductor laser 10, a structure portion 20 having a plurality of semiconductor layers is laminated on one surface of a substrate 11 having a pair of opposed surfaces. The substrate 11 is made of, for example, sapphire having a thickness in the stacking direction (hereinafter simply referred to as a thickness) of 300 μm, and the structural unit 20 is formed on the C surface of the substrate 11. The substrate 11 also has side surfaces that connect a pair of surfaces.
[0020]
The structure unit 20 includes a buffer layer 21, a base layer 22, a mask layer 23, a covering growth layer 24, a first conductive type semiconductor layer 25, an active layer 26, and a second conductive type semiconductor layer 27, which are sequentially stacked from the substrate 11 side. Respectively. The buffer layer 21 has a thickness of 30 nm, for example, and is made of undope-GaN not added with impurities. The buffer layer 21 is made of a crystal close to amorphous grown at a low temperature and serves as a nucleus when the underlayer 22 is grown. The underlayer 22 has a thickness of 2 μm, for example, and is composed of undope-GaN crystals to which no impurities are added.
[0021]
The mask layer 23 has, for example, a thickness of 0.1 μm and silicon dioxide (SiO 2₂). This mask layer 23 is also formed with a plurality of openings 23a extending in a band shape in a direction perpendicular to the paper surface in FIG. 1, and a plurality of masks formed between the openings 23a and similarly extended in a band shape. And a growth layer 24 is grown laterally on the mask layer 23 to block the propagation of threading dislocations from the underlying layer 22. The width (mask width) of each mask portion 23b in the mask layer 23 is, for example, 10 μm, and the width (opening width) of each opening portion 23a is, for example, 4 μm. The covering growth layer 24 has a thickness of 10 μm, for example, and is made of undope-GaN not added with impurities.
[0022]
The first conductivity type semiconductor layer 25 has an n-side contact layer 25a, an n-type cladding layer 25b, and a first guide layer 25c, which are sequentially stacked from the side of the covering growth layer 24. The n-side contact layer 25a has a thickness of 3 μm, for example, and is made of n-type GaN to which an n-type impurity such as silicon (Si) is added. The n-type cladding layer 25b is, for example, n-type Al having a thickness of 1 μm and added with an n-type impurity such as silicon._0.1Ga_0.9It is composed of N mixed crystal. The first guide layer 25c has, for example, a thickness of 0.1 μm and is made of n-type GaN to which an n-type impurity such as silicon is added.
[0023]
The active layer 26 is made of, for example, an undope-InGaN mixed crystal to which no impurity is added, and an In layer having a thickness of 3 nm._0.15Ga_0.85A well layer made of N mixed crystal and an In layer with a thickness of 4 nm._0.02Ga_0.98It has a multiple quantum well structure with a barrier layer made of N mixed crystal. The active layer 26 functions as a light emitting layer, and the light emission wavelength is about 405 nm in laser oscillation.
[0024]
The second conductivity type semiconductor layer 27 includes a deterioration preventing layer 27a, a second guide layer 27b, a p-type cladding layer 27c, and a p-side contact layer 27d, which are sequentially stacked from the active layer 26 side. The deterioration preventing layer 27a is, for example, p-type Al having a thickness of 20 nm and added with a p-type impurity such as magnesium (Mg)._0.2Ga_0.8It is composed of N mixed crystal. The second guide layer 27b has, for example, a thickness of 0.1 μm and is made of p-type GaN to which a p-type impurity such as magnesium is added. The p-type cladding layer 27c is, for example, p-type Al having a thickness of 0.8 μm and doped with a p-type impurity such as magnesium._0.1Ga_0.9It is composed of N mixed crystal. The p-side contact layer 27d has a thickness of 0.5 μm, for example, and is made of a p-type GaN mixed crystal to which a p-type impurity such as magnesium is added.
[0025]
The structure unit 20 having such a configuration includes a first surface 20a formed of an n-side contact layer 25a that is the first conductive type semiconductor layer 25 and a p side that is the second conductive type semiconductor layer 27 in one of the stacking directions. Each has a second surface 20b made of a contact layer 27d, and has a third surface 20c made of a buffer layer 21 on the other side in the stacking direction.
[0026]
An n-side electrode 12 as a first electrode is provided on the first surface 20 a of the structure unit 20. The n-side electrode 12 has a structure in which a titanium (Ti) layer, an aluminum (Al) layer, and a gold (Au) layer are laminated in order from the n-side contact layer 25a side and alloyed by heat treatment. The side contact layer 25a is electrically connected. On the second surface 20b of the structure portion 20, a p-side electrode 14 as a second electrode is formed through an opening 13a provided in the insulating layer 13 together with an insulating layer 13 made of an insulating material such as silicon dioxide. ing. The p-side electrode 14 has a structure in which a nickel (Ni) layer and a gold (Au) layer are sequentially laminated from the p-side contact layer 27d side and alloyed by heat treatment. The p-side contact layer 27d And are electrically connected. The p-side electrode 14 is extended in a band shape in a direction perpendicular to the paper surface in FIG. 1 so as to confine the current, and the region of the active layer 26 corresponding to the p-side electrode 14 becomes a light emitting region. It has become.
[0027]
The semiconductor laser 10 also includes an absorption portion 15 on the other surface side of the substrate 11 (the third surface 20c side of the structure portion 20). The absorber 15 is made of a material that absorbs light having a wavelength equal to or shorter than the emission wavelength in the active layer 26. For example, it is made of a metal such as gold, nickel, platinum (Pt) or aluminum, or an alloy thereof, or a dielectric such as amorphous silicon or ZnS. The absorbing portion 15 may be provided on the entire other surface side of the substrate 11, but the peripheral portion of the other surface of the substrate 11 is shown in FIG. 2 as seen from the absorbing portion 15 side. It is preferable to be provided with respect to a part to exclude. As will be described later in the manufacturing method, in such a semiconductor laser 10, the structure portion 20 is laminated on the substrate 11 having a plurality of semiconductor laser formation regions and then divided in each semiconductor laser formation region. This is because, in that case, it is easier to divide the substrate 11 when the absorbing portion 15 is not formed at the peripheral portion of the other surface.
[0028]
Further, the thickness of the absorption portion 15 is determined by the absorption coefficient of the material constituting the absorption portion 15 being α (cm^-1), And when the thickness of the absorbing portion 15 is d (cm), it is preferable that the product is determined to be 1 or more as shown in Equation 2.
[Formula 2]
α × d ≧ 1
[0029]
As can be seen from the relationship between the transmitted light intensity shown in Equation 3 and the absorption coefficient α of the absorber 15 and its thickness d (refer to Kushida Koji “Quantum Optics” Chapter 2, Asakura Shoten Publishing). This is because the transmitted light intensity cannot be sufficiently reduced unless the product of the absorption coefficient α of the absorbing portion 15 and its thickness d is 1 or more. The intrusion light intensity in Expression 3 is obtained by subtracting the re-reflection light intensity from the incident light intensity as shown in Expression 4.
[0030]
[Formula 3]
Transmitted light intensity = Intrusion light intensity × exp (−α × d)
[Formula 4]
Intrusion light intensity = incident light intensity-re-reflected light intensity
[0031]
Table 1 shows the absorption coefficient α with respect to the wavelength λ when the absorbing portion 15 is made of gold, and the thickness d when the product of the absorption coefficient α and the thickness d is 1. That is, the thickness d shown in Table 1 is a value when α × d in Equation 3 is 1, and reduces the transmitted light intensity of the light transmitted through the absorption portion 15 to about 36% of the intrusion light intensity. The value that can be. In Table 1, κ is a physical property value indicating the amount of light absorption, and the absorption coefficient α has a relationship as shown in Formula 5.
[Formula 5]
α = 4πκ / λ
[0032]
[Table 1]

[0033]
Similarly, Table 2 shows the case where the absorbing portion 15 is made of nickel, Table 3 shows the case where the absorbing portion is made of platinum, Table 4 shows the case where the absorbing portion 15 is made of aluminum, Table 5 shows the case of amorphous silicon, and Table 6 shows the case of the absorber 15 made of ZnS.
[0034]
[Table 2]

[0035]
[Table 3]

[0036]
[Table 4]

[0037]
[Table 5]

[0038]
[Table 6]

[0039]
As shown in Tables 1 to 6, when κ and the absorption coefficient α are positive values, light of the wavelength λ is absorbed. It turns out that the light which it has can be absorbed in the absorption part 15. FIG. It can also be seen that if the absorber 15 is made of these metals or silicon, light having these wavelengths can be sufficiently absorbed with a thickness d of about several nanometers to several tens of nanometers.
[0040]
The semiconductor laser 10 is further formed with a pair of reflecting mirror films 16 and 17 at end portions in the length direction of the p-side electrode 14 as shown in FIG. Each reflecting mirror film 16, 17 is made of, for example, silicon dioxide (SiO 2₂) Films and zirconium oxide (ZrO) films are alternately laminated, and the reflectance of the reflecting mirror film 17 is lowered and the reflectance of the reflecting mirror film 17 is adjusted to be higher. ing. As a result, the light generated in the active layer 26 is amplified by reciprocating between the pair of reflecting mirror films and emitted from the reflecting mirror film 16 as a laser beam. That is, the length direction of the p-side electrode 14 is the resonator direction.
[0041]
The semiconductor laser 10 having such a configuration can be manufactured as follows.
[0042]
3 and 5 show the respective manufacturing steps. 3 and 4 are cross-sectional views in the same direction as FIG. 1 (a direction perpendicular to the extending direction of the p-side electrode 14), and FIG. 5 is a view as seen from the absorber 15 side. First, as shown in FIG. 3A, for example, a substrate 11 made of sapphire having a plurality of semiconductor laser formation regions is prepared, and one surface (C surface) of the substrate 11 is made of undope-GaN by MOCVD. A buffer layer 21 is formed. At that time, for example, the temperature of the substrate 11 is lowered to 520 ° C., and a crystal layer close to amorphous is grown. The raw material is trimethylgallium ((CH_Three)_ThreeGa) and ammonia (NH_Three) Is used. In FIGS. 3 and 4, only one semiconductor laser forming region is shown as a representative.
[0043]
Next, as shown in FIG. 3A, a base layer 22 made of undope-GaN is formed on the buffer layer 21 by MOCVD, for example, in the same manner as the buffer layer 21. However, the temperature of the substrate 11 is set to, for example, 1020 ° C., which is higher than the temperature at which the buffer layer 21 is grown, and the crystal layer is grown.
[0044]
Subsequently, as shown in FIG. 3B, a mask layer having a plurality of mask portions 23b made of silicon dioxide and extended in a strip shape on the base layer 22 by, for example, a CVD (Chemical Vapor Deposition) method. 23 is selectively formed. After that, as shown in FIG. 3B, the covering growth layer 24 made of undope-GaN is grown laterally on the mask layer 23 by, for example, the MOCVD method in the same manner as the base layer 22. .
[0045]
After forming the coating growth layer 24, as shown in FIG. 3C, the n-side contact layer 25a made of n-type GaN, n-type Al, and the like are formed thereon, for example, by MOCVD._0.1Ga_0.9N-type cladding layer 25b made of N mixed crystal, first guide layer 25c made of n-type GaN, active layer 26 made of undope-GaInN mixed crystal, p-type Al_0.2Ga_0.8Deterioration preventing layer 27a made of N mixed crystal, second guide layer 27b made of p-type GaN, p-type Al_0.1Ga_0.9A p-type cladding layer 27c made of N mixed crystal and a p-side contact layer 27d made of p-type GaN are successively grown.
[0046]
At this time, for example, the temperature of the substrate 11 is set to 800 to 1000 ° C., and trimethyl aluminum ((CH_Three)_ThreeAl), trimethylgallium as a gallium source, and trimethylindium ((CH_Three)_ThreeAs the source gas for In) and nitrogen, ammonia gas is used. When silicon is added as an n-type impurity, monosilane gas (SiH) is used as a silicon source gas._Four) And adding magnesium as a p-type impurity, bis = methylcyclopentadienylmagnesium ((CH_ThreeC_FiveH_Four)₂Mg) or bis = cyclopentadienylmagnesium ((C_FiveH_Five)₂Mg) is used.
[0047]
After each layer from the n-side contact layer 25a to the p-side contact layer 27d is grown, as shown in FIG. 4A, an insulating material such as silicon dioxide is formed on the p-side contact layer 27d by, for example, the CVD method. An insulating layer 13 made of a body is formed. After forming the insulating layer 13, the lithography technique is used to correspond to the position where the n-side electrode 12 is formed. The p-side contact layer 27d, the p-type cladding layer 27c, the second guide layer 27b, the deterioration preventing layer 27a, the active layer 26, the first guide layer 25c, and the n-type cladding layer 25b are selectively removed sequentially to expose the n-side contact layer 25a. That is, the first surface 20a of the structure unit 20 is exposed.
[0048]
After exposing the n-side contact layer 25a, as shown in FIG. 4B, a resist film (not shown) is applied and formed on the entire surface (that is, on the insulating layer 13 and the n-side contact layer 25a), and photolithography is performed. Thus, a mask pattern corresponding to the formation position of the n-side electrode 12 is formed. Thereafter, a titanium layer, an aluminum layer, and a gold layer are selectively deposited on the entire surface (that is, on the n-side contact layer 25a and a resist film (not shown)) by, for example, vacuum evaporation, and a resist film (not shown) is formed thereon. The n-side electrode 12 is formed by removing together with each metal layer deposited (lift-off).
[0049]
After the n-side electrode 5 is formed, a resist film (not shown) is formed on the entire surface (that is, on the insulating layer 13, the n-side contact layer 25a and the n-side electrode 12) as shown in FIG. 4B. Then, a mask pattern corresponding to the formation position of the p-side electrode 14 is formed by photolithography. After that, etching is performed using this as a mask, and the insulating layer 13 is selectively removed to form an opening 13a corresponding to the position where the p-side electrode 14 is formed, thereby exposing the p-side contact layer 27d. That is, the second surface of the structure unit 20 is exposed. After the p-side contact layer 27d is exposed, a nickel layer and a gold layer are sequentially deposited on the entire surface (that is, on the p-side contact layer 27d and a resist film (not shown)) by, for example, a vacuum evaporation method. The p-side electrode 14 is formed by removing the metal layer deposited thereon (lift-off). After that, heat treatment is performed to alloy the p-side electrode 14 and the n-side electrode 12.
[0050]
After performing the heat treatment, as shown in FIG. 5, a resist film (not shown) is applied and formed on the other surface of the substrate 11, and a mask pattern corresponding to the formation position of the absorbing portion 15 is formed by photolithography. After that, a metal layer such as a gold layer, a platinum layer, a nickel layer, or an aluminum layer is deposited on the entire surface (that is, on the substrate 11 and a resist film (not shown)) by, for example, vacuum deposition, and a resist film (not shown) is formed thereon. Then, the absorbing portion 15 is formed by removing (lift-off) together with the deposited metal layer. In FIG. 5, a plurality of semiconductor laser forming regions 10a are shown, and a region surrounded by a broken line corresponds to each semiconductor laser forming region 10a.
[0051]
In the case where the absorber 15 is made of a semiconductor such as amorphous silicon or ZnS, for example, a CVD method, a molecular beam epitaxy (MBE) method or a MOCVD (Metal Organic Chemical Vapor) is formed on the other surface of the substrate 11. After forming the dielectric layer by the Deposition method, the absorbing portion 15 is formed by selectively removing the dielectric layer corresponding to the absorbing portion forming region using a lithography technique.
[0052]
After forming the absorbing portion 15, although not shown here, the substrate 11 is divided into a predetermined width perpendicular to the length direction of the p-side electrode 14 so as to correspond to each semiconductor laser forming region 10a. After that, the pair of reflecting mirror films 16 and 17 are formed on the pair of divided side surfaces by, for example, E-gun vapor deposition or CVD. After forming the reflecting mirror films 16 and 17, the substrate 11 is divided by a predetermined width in parallel with the length direction of the p-side electrode 14 so as to correspond to each semiconductor laser forming region 10a. In these dividing steps, as shown in FIG. 5, it is easier to divide without forming the absorbing portion 15 at the peripheral portion of each semiconductor laser forming region 10 a without hindering the absorbing portion 15. It is preferable because it is possible. Thereby, the semiconductor laser 10 shown in FIG. 1 is formed.
[0053]
The semiconductor laser 10 manufactured in this way is used by being housed in a package as follows.
[0054]
6 to 8 show the configuration of the package 30 and the state of the semiconductor laser 10 housed in the package 30. FIG. 8 is a cross-sectional view taken along the line II in FIG. First, as shown in FIG. 6, the semiconductor laser 10 is arranged with the n-side electrode 12 and the p-side electrode 14 facing each other on the arrangement substrate 31. The arrangement substrate 31 is made of, for example, an insulator such as aluminum nitride (AlN), and a wiring 32 for connecting the n-side electrode 12 and the p-side electrode 14 are provided on the surface on which the semiconductor laser 10 is arranged. And a wiring 33 for connecting the two. Each wiring 32 and 33 is comprised, for example with metals, such as gold | metal | money. A solder layer 32a is formed at a position corresponding to the n-side electrode 12 on the side opposite to the arrangement substrate 31 of the wiring 32, and a position corresponding to the p-side electrode 14 on the side opposite to the arrangement substrate 31 of the wiring 33. A solder layer 33a is formed on the surface. That is, the n-side electrode 12 of the semiconductor laser 10 is electrically connected to the wiring 32 via the solder layer 32a, and the p-side electrode 14 is electrically connected to the wiring 33 via the solder layer 33a.
[0055]
Next, as shown in FIGS. 7 and 8, the semiconductor laser 10 disposed on the placement substrate 31 is accommodated in the package 30. The package 30 includes, for example, a disk-shaped support body 34 and a hollow cylindrical cover body 35. The lid 35 is in a state where one end thereof is opened and the other end is closed, and the open end is disposed on one surface of the support 34. Inside the lid 35, a mounting table 36 is formed on one surface of the support 34, and the semiconductor laser 10 is mounted on the mounting table 36 via the arrangement substrate 31. In addition, at the closed end portion of the lid 35, an extraction window 35 a for extracting the laser beam emitted from the semiconductor laser 10 to the outside of the package 30 corresponding to the semiconductor laser 10 is provided.
[0056]
The mounting table 36 and the support 34 are made of a conductor such as metal, for example, and are electrically connected to external wiring via pins 37 provided on the support 34. The support 34 has a pin 38 that is insulated from the support 34 and penetrates from the inside to the outside, and can be electrically connected to an external wiring via the pin 38. It is like that. That is, the semiconductor laser 10 is electrically connected to the external wiring by connecting the wiring 32 of the arrangement substrate 31 and the pin 38 with a wire and connecting the wiring 33 and the mounting table 36 with a wire. The
[0057]
The semiconductor laser 10 thus housed in the package 30 operates as follows.
[0058]
In this semiconductor laser 10, when a predetermined voltage is applied between the n-side electrode 12 and the p-side electrode 14 of the semiconductor laser 10 via the pin 37 and the pin 38 of the package 30, a current flows in the active layer 26. It is injected and light emission occurs due to electron-hole recombination. This light is amplified by reciprocating between the pair of reflecting mirror films 16 and 17 and is emitted from the reflecting mirror film 16 as a laser beam. A part of the laser beam emitted from the semiconductor laser 10 is extracted outside the package 30 through the extraction window 35 a of the package 30.
[0059]
Further, another part of the laser beam emitted from the semiconductor laser 10 is reflected on the inner wall of the package 30 or the extraction window 35a as shown by the thick solid arrow in FIG. The part returns to the semiconductor laser 10. Further, a slight laser beam is emitted from the reflecting mirror film 17 of the semiconductor laser 10 and reflected on the inner wall of the package 30 as shown by a thin solid arrow in FIG. The part returns to the semiconductor laser 10. Part of the stray light that has returned to the semiconductor laser 10 becomes re-reflected light and part of it becomes intrusion light on the surface of the semiconductor laser 10.
[0060]
Here, in the semiconductor laser 10 according to the present embodiment, since the absorption portion 15 is provided on the other surface of the substrate 11, part of the stray light that has entered the semiconductor laser 10 reaches the absorption portion 15, and the absorption portion 15. In FIG. 9, a part is absorbed, and a part is transmitted as indicated by a broken-line arrow in FIG. 9. That is, the transmitted light intensity of the stray light transmitted through the absorption unit 15 is smaller than the intrusion light intensity by the amount absorbed by the absorption unit 15. Therefore, stray light in the package 30 is reduced, and stray light extracted from the extraction window 35a is also reduced. In the semiconductor laser 10 as well, stray light reaching the active layer 26 is reduced, the dynamic characteristics of the semiconductor laser 10 are stabilized, and laser noise is reduced.
[0061]
As described above, according to the semiconductor laser 10 according to the present embodiment, the absorber 15 is provided on the other surface of the substrate 11 (on the third surface 20c side of the structure portion 20). However, stray light can be absorbed by the absorber 15. Therefore, the stray light in the package 30 can be reduced, and the stray light extracted from the extraction window 35a can also be reduced. Therefore, malfunction of the apparatus using this semiconductor laser 10 can be prevented. Also in the semiconductor laser 10, stray light reaching the active layer 26 can be reduced, the dynamic characteristics of the semiconductor laser 10 can be stabilized, and laser noise can be reduced.
[0062]
In addition, according to the method for manufacturing a semiconductor laser according to the present embodiment, the absorption portion 15 is formed on the other surface of the substrate 11 (the third surface 20c side of the structure portion 20). Such a semiconductor laser 10 can be easily manufactured.
[0063]
(Second Embodiment)
FIG. 10 shows the semiconductor laser 40 according to the second embodiment of the present invention as viewed from the substrate 11 side. The semiconductor laser 40 has the same configuration and function as those of the first embodiment except that the shape of the absorbing portion 45 is different. Further, it can be manufactured in the same manner as in the first embodiment. Therefore, here, the same reference numerals are given to the same components, and detailed description thereof is omitted.
[0064]
The absorbing portion 45 has a dodecagonal shape in which cutout portions as mark portions 45a are formed at four corners of a quadrangle. As described in the first embodiment, the mark portion 45 a is formed when the semiconductor laser 40 is disposed on the placement substrate 31 or when the semiconductor laser 40 is placed on the placement table 36 of the package 30. This is used as a mark for determining the position of the laser 40. This is because the substrate 11 is made of sapphire that does not absorb light having a wavelength less than or equal to the emission wavelength, whereas the absorbing portion 45 is made of a material that absorbs the light. The semiconductor laser 40 can be positioned by identifying the mark portion 45a by image processing or the like.
[0065]
As described above, according to the present embodiment, since the absorbing portion 45 has the mark portion 45a, in addition to the effects described in the first embodiment, the semiconductor laser 40 is provided on the arrangement substrate 31. For example, when the semiconductor laser 40 is mounted on the mounting table 36 of the package 30, the positioning can be easily performed by using image processing or the like. Accordingly, tact time can be shortened, alignment accuracy can be increased, and yield can be improved.
[0066]
In the present embodiment, the absorption portion 45 is formed in a dodecagonal shape so as to form the mark portion 45a made of a notch portion. However, as in the semiconductor laser 50 shown in FIG. It may be configured to have a plurality of absorption regions 55b, and a region between each absorption region 55b may be a mark portion 55a. That is, here, the mark portions 45a and 55a refer to characteristic portions that can indicate the positions of the absorption portions 45 and 55.
[0067]
(Third embodiment)
FIG. 12 shows a semiconductor laser 60 according to the third embodiment of the present invention as viewed from the substrate 11 side. The semiconductor laser 60 has the same configuration and operation as those of the first embodiment except that the shape of the absorption portion 65 is different. Further, it can be manufactured in the same manner as in the first embodiment. Therefore, here, the same reference numerals are given to the same components, and detailed description thereof is omitted.
[0068]
The absorber 65 has a plurality of absorption regions 65b arranged in the resonator direction A (extension direction of the p-side electrode 14) with the same pitch width B as the length of an integral multiple of 1/2 of the emission wavelength. . The pitch width B is a width obtained by combining the width C of one absorption region 65b and the width D between adjacent absorption regions 65b as shown in FIG.
[0069]
As described above, according to the present embodiment, the absorber 65 has the plurality of absorption regions 65b arranged in the resonator direction A with the same pitch width B as the length that is an integral multiple of 1/2 of the emission wavelength. Thus, in addition to the effects described in the first embodiment, the same effects as DFB (Distributed Feedback) can be obtained. Therefore, the selectivity of the longitudinal mode can be increased (see Casey and Panish; “Heterostructure Lasers” Chap. 7 Academic Press).
[0070]
(Fourth embodiment)
FIG. 13 shows a semiconductor laser 70 according to the fourth embodiment of the present invention. The semiconductor laser 70 has the same configuration and operation as those of the first embodiment except that the absorbing portion 15 is removed and the substrate 71 has a function as an absorbing portion. Further, it can be manufactured in the same manner as in the first embodiment. Therefore, here, the same reference numerals are given to the same components, and detailed description thereof is omitted.
[0071]
The substrate 71 is made of, for example, sapphire in which Fe, Cu or the like is intruded or added as an impurity, and can absorb light having a wavelength equal to or shorter than the emission wavelength in the structure portion 20. Therefore, according to this embodiment, the same effect as that of the first embodiment can be obtained.
[0072]
The present invention has been described with reference to the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications can be made. For example, in each of the first to third embodiments, the material constituting the absorbers 15, 45, 55, and 65 has been described with specific examples. However, light having a wavelength equal to or shorter than the emission wavelength is described. Any material can be used as long as it can absorb, other metals such as zinc (Zn) or lead (Pb), or alloys thereof, mixed crystal semiconductors, or compounds such as oxides or nitrides Can also be used. Further, in each of the first to third embodiments, the absorbers 15, 45, 55, 65 are configured by a single layer, but may be configured by a plurality of stacked layers. Good.
[0073]
Furthermore, in each of the first to third embodiments, the shape of the absorbers 15, 45, 55, 65 has been described with specific examples, but the absorber has other shapes. Also good. For example, as shown in FIG. 14, the absorbing portion 85 may be configured by a plurality of absorbing regions 85b having different shapes. As shown in FIG. 15, the absorbing portion 95 places the absorbing region 95b on the substrate. You may make it have only in one part instead of having it over the other surface of 11.
[0074]
In addition, in each of the first to third embodiments, the case where the absorbing portions 15, 45, 55, 65 are formed on the other surface of the substrate 11 (the third surface 20c side of the structural portion 20) has been described. However, in addition to these, at least a part of the side surface (that is, the side surface of the structure unit 20 and the side surface of the substrate 11) positioned in a direction perpendicular to the stacking direction of the structure unit 20 may be provided with the absorption unit. Good. Further, instead of these, an absorbing portion may be provided only in at least a part of the side surface of the structure portion 20. However, when light is emitted from the side surface, it is necessary not to provide an absorbing portion in the region where the light is emitted. Further, when the absorption part is provided on the side surface side of the structure part 20, the thickness of the absorption part is a thickness in a direction perpendicular to the stacking direction of the structure part 20.
[0075]
Furthermore, in each of the above embodiments, the group III nitride compound semiconductor constituting the structure portion 20 has been described with a specific example. However, the present invention is not limited to other appropriate group III nitride compound semiconductors ( That is, a group III nitride compound semiconductor containing at least one group III element selected from the group consisting of gallium (Ga), aluminum (Al), boron (B) and indium (In) and nitrogen (N) ) May constitute the structural unit 20.
[0076]
In addition, in each of the above-described embodiments, the case where the structure portion 20 is formed of a group III nitride compound semiconductor has been described. However, the present invention may be applied even when the structure portion is formed of another semiconductor. The present invention can be widely applied to semiconductor light emitting devices in which both the first electrode and the second electrode are located on one side in the stacking direction of the structure portion 20. Further, the present invention can be widely applied to semiconductor light-emitting elements in which the substrate 11 is made of a material that does not absorb light having a wavelength equal to or shorter than the emission wavelength.
[0077]
Furthermore, in each of the above embodiments, the case where the first conductive semiconductor layer 25 is formed of an n-type semiconductor layer and the second conductive semiconductor layer 27 is formed of a p-type semiconductor layer has been described. Can be widely applied to the case where the first conductive semiconductor layer 25 is formed of a p-type semiconductor layer and the second conductive semiconductor layer 27 is formed of an n-type semiconductor layer.
[0078]
In addition, in each of the above-described embodiments, the configuration of the semiconductor laser has been specifically described. However, the present invention may include a first conductive semiconductor layer that is sequentially stacked, even if it has other configurations. The present invention can be widely applied to semiconductor light emitting devices including a structure portion having an active layer and a second conductivity type semiconductor layer. For example, the deterioration preventing layer 27a may not be provided, and the p-side electrode 14 may not be formed in a strip shape but may be subjected to current confinement by another method.
[0079]
Furthermore, in each of the above embodiments, only the semiconductor laser has been described. However, the present invention can be similarly applied to other semiconductor light emitting elements such as a light emitting diode.
[0080]
In addition, in each of the above-described embodiments, the case where the structure portion 20 is formed by the MOCVD method has been described. However, the structure portion 20 may be formed by another vapor phase growth method such as an MBE method or a halide method. Note that the halide vapor phase growth method is a vapor phase growth method in which halogen contributes to transport or reaction, and is also referred to as a hydride vapor phase growth method.
[0081]
【The invention's effect】
  As described above, claims 1 to5According to the semiconductor light emitting device according to any one of the following:Back side of substrateIn addition, since the absorption portion that absorbs light having a wavelength equal to or smaller than the emission wavelength is provided, for example, even if this semiconductor light emitting element is housed in a package, stray light can be absorbed by the absorption portion. As a result, stray light extracted from the package to the outside can be reduced, and malfunction of the device using the semiconductor light emitting element can be prevented. In addition, stray light reaching the active layer of the semiconductor light emitting device can be reduced, so that the dynamic characteristics of the semiconductor light emitting device can be stabilized and noise can be reduced.
[0084]
  Further claimsAny one of 6 to 9According to the method for manufacturing a semiconductor light emitting device, the semiconductor light emitting device of the present invention can be easily manufactured, and the semiconductor light emitting device of the present invention can be easily realized.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a configuration of a semiconductor laser according to a first embodiment of the invention.
2 is a view of the semiconductor laser shown in FIG. 1 as viewed from the side of the absorber.
3 is a cross-sectional view showing each manufacturing step of the semiconductor laser shown in FIG. 1. FIG.
4 is a cross-sectional view showing a manufacturing process subsequent to FIG. 3. FIG.
5 is a diagram illustrating a manufacturing process subsequent to FIG. 4. FIG.
6 is a diagram illustrating a state when the semiconductor laser illustrated in FIG. 1 is used. FIG.
7 is a diagram showing a state when the semiconductor laser shown in FIG. 1 is used. FIG.
8 is a cross-sectional view taken along line II in FIG.
9 is a cross-sectional view taken along line II in FIG. 7 for explaining the operation of the semiconductor laser shown in FIG.
FIG. 10 is a diagram illustrating a semiconductor laser according to a second embodiment of the present invention.
11 is a diagram showing a modification of the semiconductor laser shown in FIG.
FIG. 12 is a diagram illustrating a semiconductor laser according to a third embodiment of the present invention.
FIG. 13 is a sectional view showing a configuration of a semiconductor laser according to a fourth embodiment of the invention.
FIG. 14 is a view showing a modification of the semiconductor light emitting element according to the present invention.
FIG. 15 is a diagram illustrating another modification of the semiconductor light emitting element according to the present invention.
FIG. 16 is a cross-sectional view showing a state in which a conventional semiconductor light emitting element is used.
FIG. 17 is a cross-sectional view showing a state when another conventional semiconductor light emitting element is used.
FIG. 18 is a diagram illustrating an optical system including a semiconductor light emitting element and a collimator lens.
FIG. 19 is a cross-sectional view for explaining problems of a conventional semiconductor light emitting element.
FIG. 20 is a diagram for explaining the relationship among reflection, transmission, and absorption when light is incident on a substance.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10,40,50,60,70 ... Semiconductor laser (semiconductor light emitting element), 10a ... Semiconductor laser formation area, 11, 71, 211 ... Substrate, 12 ... N-side electrode, 13 ... Insulating layer, 13a ... Opening, 14 ... p-side electrode, 15, 45, 55, 65, 85, 95 ... absorbing part, 20 ... structure part, 20a ... first surface, 20b ... second surface, 20c ... third surface, 21 ... buffer layer, 22 ... bottom Base layer, 23 ... mask layer, 24 ... covering growth layer, 25 ... first conductive type semiconductor layer, 25a ... n-side contact layer, 25b ... n-type cladding layer, 25c ... first guide layer, 26 ... active layer, 27 2nd conductivity type semiconductor layer, 27a ... Deterioration prevention layer, 27b ... 2nd guide layer, 27c ... p-type cladding layer, 27d ... p-side contact layer, 30, 130, 230 ... package, 31 ... disposition substrate, 32, 33 ... wiring, 32a, 33a Solder layer, 34, 134 ... support, 35, 135 ... lid, 35a, 135a, 235a ... take-out window, 36, 136, 236 ... mounting table, 37, 38 ... pin, 39 ... wire, 110, 210 ... semiconductor Light emitting element, 300 ... collimator lens, A ... direction of resonator, M ... material, L1 ... incident light, L2 ... reflected light, L3 ... transmitted light

Claims (9)

A semiconductor light emitting device housed in a package having a window,
A substrate,
Each of the first conductive type semiconductor layer, the active layer, and the second conductive type semiconductor layer sequentially stacked on the substrate has a plurality of side surfaces positioned in a direction perpendicular to the stacking direction and one of the stacking directions. Two surfaces facing each other among the plurality of side surfaces, each having a first surface made of the first conductivity type semiconductor layer and a second surface made of the second conductivity type semiconductor layer located in one of the stacking directions. A pair of reflecting mirror films constituting a resonator structure, and a structure part that emits light generated in the active layer from one of the reflecting films toward the window part of the package;
A first electrode provided on the first surface of the structure portion;
A second electrode provided on the second surface of the structure portion;
An absorption part that is provided on the back surface of the substrate and absorbs light having a wavelength equal to or shorter than the emission wavelength in the structure part ;
The absorber has a plurality of absorption regions, and the plurality of absorption regions are arranged at the same pitch width as a length that is an integral multiple of 1/2 of the emission wavelength along the resonator direction. A semiconductor light emitting device. A semiconductor light emitting device housed in a package having a window,
Each of the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer is sequentially stacked, and has a plurality of side surfaces positioned in a direction perpendicular to the stacking direction. A pair of reflecting mirror films constituting a resonator structure on the two surfaces, and a structure part that emits light generated in the active layer from one of the reflecting films toward the window part of the package;
The structure portion is stacked on one surface of a pair of opposing surfaces, and has a side surface positioned in a direction perpendicular to the stacking direction of the structure portion, and has light having a wavelength equal to or less than the emission wavelength of the structure portion. A substrate made of a material that does not absorb,
Provided on the other surface to the one surface facing the substrate, and a absorption portion which absorbs light having a wavelength less than or equal to the emission wavelength of the structure,
The absorber has a plurality of absorption regions, and the plurality of absorption regions are arranged at the same pitch width as a length that is an integral multiple of 1/2 of the emission wavelength along the resonator direction. A semiconductor light emitting device. The product of the absorption coefficient (unit: cm ^-1 ) of the material constituting the absorption part and the thickness (unit: cm) of the absorption part is larger than 1, 3 or The semiconductor light emitting element as described.   The first conductivity type semiconductor layer, the active layer, and the second conductivity type semiconductor layer of the structure portion are at least one selected from the group consisting of gallium (Ga), aluminum (Al), boron (B), and indium (In). 3. The semiconductor light-emitting device according to claim 1, wherein the semiconductor light-emitting device comprises a group III nitride compound semiconductor containing a group III element and nitrogen (N). 5. The semiconductor light emitting device according to claim 4 , wherein the substrate is a sapphire substrate. A first conductive type semiconductor layer, an active layer, and a second conductive type semiconductor layer are sequentially stacked on a substrate, and a plurality of side surfaces positioned in a direction perpendicular to the stacking direction and a first positioned in one of the stacking directions. Each of the plurality of side surfaces has a resonator structure on a first surface made of a conductive semiconductor layer and a second surface made of a second conductive semiconductor layer located on one side in the stacking direction. Forming a structure part that has a pair of reflecting mirror films constituting the light source and emits light generated in the active layer from one of the reflecting films;
Forming a first electrode on the first surface of the structural part,
Forming a second electrode on the second surface of the structural part,
Forming on the back surface of the substrate an absorbing portion that absorbs light having a wavelength equal to or shorter than the emission wavelength in the structure portion ,
A method of manufacturing a semiconductor light emitting device, wherein a plurality of absorption regions are formed as the absorbing portion along the resonator direction and arranged at the same pitch width as an integral multiple of 1/2 of the emission wavelength. . One surface of a pair of surfaces of a substrate made of a material that has a pair of opposing surfaces and a side surface connecting the pair of surfaces and does not absorb light having a wavelength equal to or shorter than the emission wavelength in the structure portion, A conductive semiconductor layer, an active layer, and a second conductive semiconductor layer are sequentially stacked, have a plurality of side surfaces positioned in a direction perpendicular to the stacking direction, and resonate with two opposing surfaces of the plurality of side surfaces. Forming a structure part having a pair of reflecting mirror films constituting a vessel structure and emitting light generated in the active layer from one of the reflecting films;
The other surface to the one surface facing the substrate, and forming an absorbing portion for absorbing light having a wavelength of less than the emission wavelength of the structure,
A method of manufacturing a semiconductor light emitting device, wherein a plurality of absorption regions are formed as the absorbing portion along the resonator direction and arranged at the same pitch width as an integral multiple of 1/2 of the emission wavelength. . The material and thickness of the absorption part are set so that the product of the absorption coefficient (unit: cm ⁻¹ ) of the material constituting the absorption part and the thickness of the absorption part (unit: cm) is greater than 1. The method of manufacturing a semiconductor light emitting element according to claim 6 , wherein the method is determined. At least one selected from the group consisting of gallium (Ga), aluminum (Al), boron (B), and indium (In) is used as the first conductive semiconductor layer, the active layer, and the second conductive semiconductor layer of the structure portion. The method of manufacturing a semiconductor light emitting device according to claim 6 , wherein the semiconductor light emitting device is formed of a group III nitride compound semiconductor containing a group III element and nitrogen (N).

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