【０００１】
【発明の属する技術分野】
本発明は、光通信分野等に用いられ、光半導体素子を収納するための光半導体素子収納用パッケージおよび光半導体装置に関する。
【０００２】
【従来の技術】
従来、光通信分野に使用されて電気信号を光信号に変換する半導体レーザ（ＬＤ）や光信号を電気信号に変換するフォトダイオード（ＰＤ）等の光半導体素子を収容するための光半導体素子収納用パッケージ（以下、パッケージともいう）を図３に示す。
【０００３】
同図に示すように、パッケージは、アルミナ（Ａｌ２Ｏ３）質焼結体（アルミナセラミックス）等のセラミックス、またはエポキシ樹脂，ポリフェニレンサルファイト（ＰＰＳ），液晶ポリマー（ＬＣＰ）等から成るエンジニアプラスチック等の電気絶縁材料から成り、上面に形成された凹部２１ｂの底面の中央部に光半導体素子２８を載置するための凸部２１ａを有し、側壁部２２に貫通孔２２ａを設けた基体２１と、貫通孔２２ａの内側に取付された集光レンズ等としての透光性部材２６と、両端が側壁部２２の内外に突出するように取着され、側壁部２２の外側に突出する一端が外部電気回路に電気的に接続される複数の外部リード端子２４とから基本的に構成される。なお、側壁部２２を別体の枠部とし、その枠部を平板状の基体２１の上面の外周部に接合する場合もある。
【０００４】
また、基体２１の側壁部２２の上面に樹脂接着材等の封止材を介して取着され、内部を気密に封止する蓋体２３を設けることにより光半導体装置となる。即ち、基体２１の凸部２１ａ上に光半導体素子２８を載置固定するとともに光半導体素子２８の各電極を外部リード端子２４にボンディングワイヤ２５等の接続手段を介して電気的に接続し、しかる後、側壁部２２の上面に蓋体２３を封止材を介して接合し、基体２１と蓋体２３とから成る容器内部に光半導体素子２８を収容することによって製品としての光半導体装置となる。
【０００５】
なお、基体２１はエポキシ樹脂やエンジニアプラスチック等を用いてインジェクションモールド法やトランスファモールド法によって一体的に成型され、その際複数の外部リード端子２４と貫通孔２２ａに設けられた透光性部材２６は、成型時に基体２１に組み込まれた状態で設けることができる。また基体２１は、全体をセラミックスで作製する、または底板部をセラミックスで作製し側壁部２２をＦｅ−Ｎｉ−Ｃｏ合金等の金属で構成する、または底板部を銅（Ｃｕ）−タングステン（Ｗ）等で作製し側壁部２２をＦｅ−Ｎｉ−Ｃｏ合金等の金属で構成するといった方法で作製することもできる。
【０００６】
また透光性部材２６は、基体２１に組み込まれる代わりに蓋体２３に組み込まれる場合もある（例えば、下記の特許文献１参照）。
【０００７】
この光半導体装置は、光半導体素子２８に外部リード端子２４を介して外部電気回路から供給される駆動信号を印加し、光半導体素子２８に光を励起させるとともに励起した光を光ファイバ２７で伝達させることによって、または光ファイバ２７を伝達する光を光半導体素子２８に受光させ、光半導体素子２８により電気信号を発生させるとともに発生した電気信号を外部リード端子２４を介して外部に取り出すことによって作動する。このような光半導体装置は光通信分野に多用される。
【０００８】
【特許文献１】
特開２００２−９４０３５号公報
【０００９】
【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、基体２１と複数の外部リード端子２４と貫通孔２２ａに設けられた透光性部材２６とが、あるいは、特許文献１に示されるように蓋体２３と透光性部材２６とが、エポキシ樹脂等の樹脂を成型することにより一体的に構成されており、光半導体素子２８に対する透光性部材２６の位置精度は良いのであるが、樹脂に直接透光性部材２６を取り付けているため、透光性部材２６の表面に樹脂の成型バリが付着し、透光性部材２６を入出射する光信号を効率良く伝送できなくなるという問題があった。
【００１０】
また、成型時に透光性部材２６の位置を固定するためにガラス等から成る透光性部材２６を金型で直接押さえなければならず、透光性部材２６にクラック等の損傷が発生し易かった。さらに、樹脂と透光性部材２６との熱膨張差が大きいため、基体２１に取り付けた後にも透光性部材２６にクラック等の破損が発生するという問題もあった。
【００１１】
また、球状やレンズ状の透光性部材２６は、貫通孔２２ａの内面との接触面積が小さいため、ガラス等から成る透光性部材２６と樹脂から成る基体２１との熱膨張差によって気密が破れ易いという問題点も有していた。
【００１２】
従って、本発明は上記問題点に鑑みて完成されたものであり、その目的は、光半導体素子に対する透光性部材の位置精度を良い状態で維持できるようにし、また透光性部材に基体の成型時の樹脂がバリとして付着するのを防止するとともに透光性部材にクラック等の破損が発生するのを防止し、さらに気密性を向上させた光半導体素子収納用パッケージおよび光半導体装置を提供することにある。
【００１３】
【課題を解決するための手段】
本発明の光半導体素子収納用パッケージは、上面に形成された凹部の底面に光半導体素子を上面に載置する凸部が設けられている基体と、前記凹部から前記基体の外側面にかけて形成された貫通孔と、該貫通孔に嵌着されるとともに外周面に形成された突部が前記基体の内部に埋め込まれている筒状の金属部材と、該金属部材の内側に取着された透光性部材とを具備していることを特徴とする。
【００１４】
本発明の光半導体素子収納用パッケージは、基体の貫通孔に嵌着されるとともに外周面に形成された突部が基体の内部に埋め込まれている筒状の金属部材と、この金属部材の内側に取着された透光性部材とを具備していることから、光半導体素子収納用パッケージの透光性部材の部位における気密性が大幅に向上する。また、例えば基体が樹脂から成る場合、基体を成型する際に透光性部材に樹脂のバリが付着するのを防ぐことができ、また、成型時に透光性部材に金型が直接当接しないことおよび製造後に樹脂から成る基体が透光性部材に直接接していないことから、透光性部材にクラック等の破損が発生するのを防ぐことができる。
【００１５】
本発明の光半導体素子収納用パッケージにおいて、好ましくは、前記金属部材は、前記突部の軸方向の厚みが前記金属部材の中心軸から離れるに伴って漸次薄くなっていることを特徴とする。
【００１６】
本発明の光半導体素子収納用パッケージは、金属部材は、突部の軸方向の厚みが金属部材の中心軸から離れるに伴って漸次薄くなっていることから、金属部材と基体との熱膨張差による応力を局所的に集中させることなく金属部材と基体との界面全体に分散させ、金属部材に加わる応力によって透光性部材が歪むのを有効に抑えることができ、その結果、透光性部材を透過する光信号にノイズ等を発生させることなく、光信号を正常かつ安定に伝送させることができる。
【００１７】
本発明の光半導体装置は、上記本発明の光半導体素子収納用パッケージと、前記透光性部材に光学的に結合するように前記凸部の上面に載置固定された光半導体素子と、前記基体の上面の前記凹部の周囲に取着された蓋体とを具備していることを特徴とする。
【００１８】
本発明の光半導体装置は、上記の構成により、上記本発明の光半導体素子収納用パッケージを用いた光結合効率に優れるとともに気密信頼性の高いものとなる。
【００１９】
【発明の実施の形態】
本発明の光半導体素子収納用パッケージおよび光半導体装置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例を示し、１は基体、１ａは光半導体素子８を載置するための凸部、２は基体１の側壁部、２ａは基体１の貫通孔、３は蓋体、４は外部リード端子、５は電気的な接続手段としてのボンディングワイヤ、６は金属部材、６ｂは透光性部材、７は光ファイバ、８は光半導体素子である。そして、上面に形成された凹部１ｂの底面に光半導体素子８を載置し収容する基体１によって、内部に光半導体素子８を収容するための容器が基本的に構成される。
【００２０】
本発明のパッケージは、上面に形成された凹部１ｂの底面に光半導体素子８を上面に載置する凸部１ａが設けられている基体１と、凹部１ｂから基体１の外側面にかけて形成された貫通孔２ａと、貫通孔２ａに嵌着されるとともに外周面に形成された突部６ｄが基体１の内部に埋め込まれている筒状の金属部材６と、金属部材６の内側６ａに取着された透光性部材６ｂとを具備している。
【００２１】
本発明の基体１は、光半導体素子８を収容し支持する支持部材であり、その上面の凹部１ｂの底面の中央部に光半導体素子８を載置するための凸部１ａを有しており、凸部１ａの上面に光半導体素子８が接着剤等により載置固定される。基体１の側壁部２は、その内側に光半導体素子８を収容するための空所を形成する。また、基体１の側壁部２を別体の枠部とし、その枠部を基体１の底板部の上面の外周部に凸部１ａを囲繞するように接合してもよい。
【００２２】
この基体１は、エポキシ樹脂、ＰＰＳやＬＣＰ等から成るエンジニアプラスチック等の電気的に絶縁性の樹脂、アルミナ（Ａｌ２Ｏ３）質焼結体（アルミナセラミックス）等のセラミックス、セラミックスと樹脂の複合材料、ガラス、ガラスセラミックス、金属等から成る。
【００２３】
そして、金属部材６が基体１の貫通孔２ａに嵌着されるとともに外周面に形成された突部６ｄが基体１の内部に埋め込まれた構成は、例えば樹脂から成る基体１をトランスファモールド法またはインジェクションモールド法等によって成型する際に、予め金型の所定位置に金属部材６を設置しておくことによって達成される。
【００２４】
また、基体１の側壁部２には両端が側壁部２の内外に突出する複数の外部リード端子４が設けられており、外部リード端子４の側壁部２内側に突出する部位には光半導体素子８の各電極がボンディングワイヤ５を介して電気的に接続されており、外部リード端子４の側壁部２の外側に突出する部位を外部電気回路に電気的に接続することによって、光半導体素子８の各電極は外部リード端子４を介し外部電気回路に電気的に接続されることとなる。
【００２５】
外部リード端子４は鉄（Ｆｅ）−ニッケル（Ｎｉ）−コバルト（Ｃｏ）合金やＦｅ−Ｎｉ合金等の金属から成り、例えばＦｅ−Ｎｉ−Ｃｏ合金等から成るインゴット（塊）に圧延加工法や打ち抜き加工法等の従来周知の金属加工法を施すことによって所定形状に形成される。この外部リード端子４の側壁部２への取着は、基体１をトランスファモールド法またはインジェクションモールド法により形成する際に、予め金型内の所定位置に外部リード端子４をセットしておくことによって、側壁部２の所定位置に両端を側壁部２の内外に突出させた状態で一体的に取着される。
【００２６】
また外部リード端子４は、その露出する表面に良導電性で耐蝕性に優れかつロウ材と濡れ性の良いＮｉやＡｕ（金）等の金属をめっき法により所定厚み（１〜２０μｍ程度）に被着させておくのがよく、外部リード端子４の酸化腐蝕を有効に防止できるとともに、外部リード端子４とボンディングワイヤ５との接続および外部リード端子４と外部電気回路との接続を信頼性の高いものとなすことができる。
【００２７】
本発明の透光性部材６ｂは、ガラス、サファイア等から成るが、透明性およびある程度の硬度が確保できれば樹脂から成っていてもよい。
【００２８】
内側６ａに透光性部材６ｂが取着された金属部材６は、光半導体素子８の光入出射部に透光性部材６ｂが対向する状態で固定され、その外側の端面に、光ファイバ７の光入出射端が金属ホルダ等を介して光半導体素子８と対向するように、樹脂接着剤、Ａｇロウ，Ａｕ−Ｓｎロウ等のロウ材、半田、ＹＡＧレーザ溶接等の溶接法などによって接合され固定される。この金属部材６は、Ｆｅ−Ｎｉ−Ｃｏ合金やＦｅ−Ｎｉ合金等の金属から成り、Ｆｅ−Ｎｉ−Ｃｏ合金等に従来周知の圧延加工法やプレス成形法等の金属加工法を施すことによって、所望の形状になるように製作される。
【００２９】
金属部材６は突部６ｄが外周面に形成された筒状である。これにより、金属部材６の体積を小さくして、透光性部材６ｂに加わる金属部材６との熱膨張差による応力を最小限に抑えることができ、透光性部材６ｂにクラック等の破損が生ずるのを防止できる。また、突部６ｄが基体１に埋め込まれているので、金属部材６と基体１の密着性を向上させ、金属部材６を基体１に強固に固定することができる。以上により、パッケージの透光性部材６ｂの部位における気密性が大幅に向上する。
【００３０】
好ましくは、図２に示すように金属部材６は突部６ｄの軸方向の厚みが金属部材６の中心軸から離れるに伴って漸次薄くなっているのがよい。この構成により、金属部材６と基体１との熱膨張差による応力を局所的に集中させることなく金属部材６と基体１との界面全体に分散させ、金属部材６に加わる応力によって透光性部材６ｂが歪むのを有効に抑えることができ、その結果、透光性部材６ｂを透過する光信号にノイズ等を発生させることなく、光信号を正常かつ安定に伝送させることができる。
【００３１】
また、図２のものにおいて、突部６ｄの先端が円弧状等の曲面となっていることがよく、金属部材６に加わる応力を有効に分散させることができる。また、突部６ｄ全体が曲面状となっていてもよく、その場合も応力を有効に分散させ得る。
【００３２】
さらに、図２では、突部６ｄが金属部材６の筒状部６ｃの側面全面から突出した形状であるが、突部６ｄが筒状部６ｃの側面の一部から突出し、端部に近づくに伴って厚みが漸次薄くなっていてもよい。この場合、金属部材６と基体１との密着性がより向上するとともに、金属部材６に加わる応力を有効に分散させることができる。
【００３３】
また、透光性部材６ｂが取着された金属部材６の側壁部２への取着は、基体１が樹脂から成る場合に基体１をトランスファモールド法またはインジェクションモールド法より成型する際に、予め金型内の所定位置に透光性部材６ｂが取着された金属部材６をセットしておき、金属部材６の外周端部が側壁部２の貫通孔２ａの内周面に埋めこまれるようにして行なわれる。
【００３４】
透光性部材６ｂが取着された金属部材６を金型内にセットする際、金属部材６の筒状部６ｃを金型で押しつけて位置を固定させれば良く、これにより透光性部材６ｂに金型が直接接しないことから透光性部材６ｂにクラック等の破損が発生するのを防止できる。また、透光性部材６ｂが取着された金属部材６は、基体１を成型する際に同時に側壁部２の所定位置に一体的に取着されることから、パッケージおよび光半導体素子８に対する透光性部材６ｂの位置精度は良好になり、また透光性部材６ｂの表面に成型時の樹脂のバリが付着するのを防ぐことができる。
【００３５】
また、Ｆｅ−Ｎｉ−Ｃｏ合金等の低熱膨張係数を有する金属から成る金属部材６と透光性部材６ｂとは熱膨張差が小さいため、製造後に熱膨張差に起因して透光性部材６ｂにクラック等の破損が発生するのを防止できる。さらに、金属部材６は、その外周端部が基体１の貫通孔２ａの内周面に埋め込まれて設置されるため、透光性部材６ｂおよび金属部材６における気密性が大幅に向上する。
【００３６】
従って、基体１と蓋体３とで構成される容器の封止が完全となり、容器内部に収納する光半導体素子８を長期にわたり正常かつ安定に作動させることが可能となる。
【００３７】
また、透光性部材６ｂの光軸方向の厚さは、金属部材６の光軸方向の両端面（両主面）間の厚さと略同じであるか、または金属部材６の両端面間の厚さよりも小さい方が好ましい。透光性部材６ｂの光軸方向の厚さが金属部材６の両端面間の厚さよりも大きくなると、基体１を成型する際に透光性部材６ｂに樹脂のバリが付着したり、透光性部材６ｂに金型が当接して透光性部材６ｂに損傷が発生し易くなる。また、以上より金属部材６の光軸方向の厚さは透光性部材６ｂの厚さと同程度であり、０．５〜７ｍｍ程度である。
【００３８】
透光性部材６ｂが取着された金属部材６に接合されている光ファイバ７は、光半導体素子８が発する光を外部に伝達する、または外部から光を光半導体素子８に伝達するための光の伝達路として機能する。
【００３９】
さらに、側壁部２の上面には樹脂接着剤等から成る封止材を介して蓋体３が取着され、蓋体３で基体１の内側を塞ぐことよって基体１と蓋体３とで構成される容器内に光半導体素子８が収容される。
【００４０】
また本発明において、基体１が樹脂から成り、基体１の内部に埋め込まれた金属部材６の突部６ｄの表面粗さが最大高さで１．６〜２５μｍとされていることが好ましい。突部６ｄの表面粗さの最大高さ（ＪＩＳ Ｂ ０６０１）を１．６〜２５μｍとすることにより、金属部材６を基体１に強固に固定でき、光半導体素子８を気密に封止できる。さらに、基体１の内外に気圧差が生じて金属部材６に圧力が加わった場合でも、金属部材６が基体１の所定の位置からずれることを防止できる。従って、透光性部材６ｂが取着された金属部材６と光半導体素子８とをより正確に対向させ、透光性部材６ｂと光半導体素子８との間における光結合効率を高効率に維持できる。
【００４１】
金属部材６の突部６ｄの表面の最大高さが１．６μｍ未満では、基体１と金属部材６との間で密着性不足が発生し、気密不良が起こり易くなる。２５μｍを超えると、エポキシ系熱硬化樹脂が逆に流れにくくなり、そのため、成形不良、ボイド等が発生し、気密不良が起こり易くなる。
【００４２】
かくして、本発明のパッケージは、透光性部材６ｂが取着された金属部材６を透光性部材６ｂが光半導体素子８と対向するように側壁部２に固定している基体１の凸部１ａの上面に光半導体素子８を載置固定し、光半導体素子８の各電極を所定の外部リード端子４にボンディングワイヤ５を介して電気的に接続し、光ファイバ７を金属部材６に接合し、しかる後、側壁部２の上面に蓋体３を封止材を介して取着し、基体１と蓋体３とから成る容器内部に光半導体素子８を収容することによって製品としての光半導体装置となる。
【００４３】
この光半導体装置は、光半導体素子８に外部リード端子４を介して外部電気回路から供給される駆動信号を入力し、光半導体素子８に光を励起させるとともに励起した光を透光性部材６ｂを通して光ファイバ７に伝達させることによって、または光ファイバ７を伝達してきた光を透光性部材６ｂを通して光半導体素子８に受光させ、受光した光に対応する電気信号を光半導体素子８で発生させ、その電気信号を外部リード端子４を介し取り出すことによって作動することとなり、このような光半導体装置は光通信分野等に使用される。
【００４４】
なお、本発明は上述の実施の形態に限定されるものではなく、本発明の要旨を逸脱しない範囲であれば種々の変更は可能である。
【００４５】
【発明の効果】
本発明の光半導体素子収納用パッケージは、上面に形成された凹部の底面に光半導体素子を上面に載置する凸部が設けられている基体と、凹部から基体の外側面にかけて形成された貫通孔と、この貫通孔に嵌着されるとともに外周面に形成された突部が基体の内部に埋め込まれている筒状の金属部材と、この金属部材の内側に取着された透光性部材とを具備していることから、光半導体素子収納用パッケージの透光性部材の部位における気密性が大幅に向上する。また、例えば基体が樹脂から成る場合、基体を成型する際に透光性部材に樹脂のバリが付着するのを防ぐことができ、また、成型時に透光性部材に金型が直接当接しないことおよび製造後に樹脂から成る基体が透光性部材に直接接していないことから、透光性部材にクラック等の破損が発生するのを防ぐことができる。
【００４６】
本発明の光半導体素子収納用パッケージは、金属部材は、突部の軸方向の厚みが金属部材の中心軸から離れるに伴って漸次薄くなっていることから、金属部材と基体との熱膨張差による応力を局所的に集中させることなく金属部材と基体との界面全体に分散させ、金属部材に加わる応力によって透光性部材が歪むのを有効に抑えることができ、その結果、透光性部材を透過する光信号にノイズ等を発生させることなく、光信号を正常かつ安定に伝送させることができる。
【００４７】
本発明の光半導体装置は、上記本発明の光半導体素子収納用パッケージと、透光性部材に光学的に結合するように凸部の上面に載置固定された光半導体素子と、基体の上面の凹部の周囲に取着された蓋体とを具備していることにより、上記本発明の光半導体素子収納用パッケージを用いた光結合効率に優れるとともに気密信頼性の高いものとなる。
【図面の簡単な説明】
【図１】本発明の光半導体素子収納用パッケージについて実施の形態の例を示す断面図である。
【図２】本発明の光半導体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３】従来の光半導体素子収納用パッケージの例を示す断面図である。
【符号の説明】
１：基体
１ａ：凸部
１ｂ：凹部
２ａ：貫通孔
３：蓋体
６：金属部材
６ｂ：透光性部材
６ｄ：突部
８：光半導体素子[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical semiconductor element housing package for housing an optical semiconductor element and an optical semiconductor device used in an optical communication field or the like.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, an optical semiconductor element housing for housing an optical semiconductor element such as a semiconductor laser (LD) that converts an electric signal into an optical signal and a photodiode (PD) that converts an optical signal into an electric signal, which are used in the field of optical communication. FIG. 3 shows a package for use (hereinafter, also referred to as a package).
[0003]
As shown in the figure, the package is made of ceramics such as alumina (Al 2 O 3 ) sintered body (alumina ceramics) or engineered plastic made of epoxy resin, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), etc. Base 21 having a convex portion 21a for mounting an optical semiconductor element 28 at the center of the bottom surface of the concave portion 21b formed on the upper surface, and having a through hole 22a formed in the side wall portion 22. And a translucent member 26 such as a condensing lens attached to the inside of the through hole 22a, and one end protruding outside the side wall 22 is attached so that both ends protrude inside and outside the side wall 22. It is basically composed of a plurality of external lead terminals 24 electrically connected to an external electric circuit. In some cases, the side wall portion 22 is formed as a separate frame portion, and the frame portion is joined to the outer peripheral portion of the upper surface of the flat substrate 21.
[0004]
An optical semiconductor device is provided by providing a lid 23 attached to the upper surface of the side wall 22 of the base 21 via a sealing material such as a resin adhesive and hermetically sealing the inside. That is, the optical semiconductor element 28 is mounted and fixed on the convex portion 21a of the base 21, and each electrode of the optical semiconductor element 28 is electrically connected to the external lead terminal 24 via the connection means such as the bonding wire 25. Thereafter, a lid 23 is joined to the upper surface of the side wall 22 via a sealing material, and the optical semiconductor element 28 is accommodated in a container formed of the base 21 and the lid 23, whereby an optical semiconductor device as a product is obtained. .
[0005]
The base 21 is integrally molded by an injection molding method or a transfer molding method using an epoxy resin, an engineering plastic, or the like. At this time, the plurality of external lead terminals 24 and the translucent member 26 provided in the through hole 22a are formed. It can be provided in a state of being incorporated into the base 21 at the time of molding. The base 21 is entirely made of ceramics, or the bottom plate is made of ceramics, and the side wall 22 is made of a metal such as an Fe-Ni-Co alloy, or the bottom plate is made of copper (Cu) -tungsten (W). The side wall 22 may be made of a metal such as an Fe-Ni-Co alloy.
[0006]
The translucent member 26 may be incorporated into the lid 23 instead of being incorporated into the base 21 (for example, see Patent Document 1 below).
[0007]
In this optical semiconductor device, a drive signal supplied from an external electric circuit is applied to the optical semiconductor element 28 via the external lead terminal 24 to excite the optical semiconductor element 28 and transmit the excited light through the optical fiber 27. Or by causing the optical semiconductor element 28 to receive light transmitted through the optical fiber 27, generating an electric signal by the optical semiconductor element 28, and extracting the generated electric signal to the outside via the external lead terminal 24. I do. Such an optical semiconductor device is frequently used in the optical communication field.
[0008]
[Patent Document 1]
JP-A-2002-94035
[Problems to be solved by the invention]
However, in the above-described conventional package, the base 21, the plurality of external lead terminals 24, and the light-transmitting member 26 provided in the through hole 22a, or the lid 23 and the light-transmitting member The transparent member 26 is integrally formed by molding a resin such as an epoxy resin, and the positional accuracy of the transparent member 26 with respect to the optical semiconductor element 28 is good. Since the light-transmitting member 26 is attached, resin molding burrs adhere to the surface of the light-transmitting member 26, and there is a problem that an optical signal that enters and exits the light-transmitting member 26 cannot be transmitted efficiently.
[0010]
Further, in order to fix the position of the translucent member 26 at the time of molding, the translucent member 26 made of glass or the like must be directly pressed by a mold, so that the translucent member 26 is easily damaged by cracks or the like. Was. Furthermore, since the difference in thermal expansion between the resin and the translucent member 26 is large, there is also a problem that the translucent member 26 may be damaged such as cracks even after being attached to the base 21.
[0011]
Further, since the spherical or lens-shaped translucent member 26 has a small contact area with the inner surface of the through hole 22a, airtightness is caused by a difference in thermal expansion between the translucent member 26 made of glass or the like and the base 21 made of resin. There was also a problem that it was easily broken.
[0012]
Therefore, the present invention has been completed in view of the above problems, and an object of the present invention is to maintain the positional accuracy of a light transmitting member with respect to an optical semiconductor element in a good state, and to provide a light transmitting member with a base. Provided is a package for storing an optical semiconductor element and an optical semiconductor device, which prevent the resin at the time of molding from attaching as burrs, prevent the light-transmitting member from being damaged such as cracks, and further improve the airtightness. Is to do.
[0013]
[Means for Solving the Problems]
An optical semiconductor element housing package of the present invention is formed from a base provided with a convex portion on which an optical semiconductor element is mounted on an upper surface on a bottom surface of a concave portion formed on an upper surface, and from the concave portion to an outer surface of the substrate. A through-hole, a cylindrical metal member fitted into the through-hole and having a protrusion formed on the outer peripheral surface embedded in the base, and a through-hole attached to the inside of the metal member. And an optical member.
[0014]
An optical semiconductor element housing package according to the present invention includes a cylindrical metal member fitted into a through hole of a base and having a protrusion formed on an outer peripheral surface embedded inside the base, , The airtightness at the portion of the light transmitting member of the package for storing an optical semiconductor element is greatly improved. Further, for example, when the base is made of a resin, it is possible to prevent burrs of the resin from adhering to the light transmitting member when the base is molded, and the mold does not directly contact the light transmitting member at the time of molding. In addition, since the base made of resin is not in direct contact with the translucent member after manufacturing, it is possible to prevent the translucent member from being damaged such as cracks.
[0015]
In the package for housing an optical semiconductor element according to the present invention, preferably, the metal member is characterized in that an axial thickness of the protrusion gradually decreases with increasing distance from a central axis of the metal member.
[0016]
In the package for housing an optical semiconductor element of the present invention, the metal member has a smaller thermal expansion difference between the metal member and the base since the axial thickness of the protrusion gradually decreases as the distance from the central axis of the metal member increases. The stress caused by the metal member is dispersed over the entire interface between the metal member and the base without locally concentrating, so that the light-transmitting member can be effectively prevented from being distorted by the stress applied to the metal member. As a result, the light-transmitting member The optical signal can be transmitted normally and stably without generating noise or the like in the optical signal transmitted through the optical signal.
[0017]
The optical semiconductor device of the present invention includes the optical semiconductor element housing package of the present invention, an optical semiconductor element mounted and fixed on an upper surface of the convex portion so as to be optically coupled to the translucent member, A lid attached around the recess on the upper surface of the base.
[0018]
With the above configuration, the optical semiconductor device of the present invention has excellent optical coupling efficiency using the optical semiconductor element housing package of the present invention and has high airtight reliability.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
The package for storing an optical semiconductor element and the optical semiconductor device of the present invention will be described in detail below. FIG. 1 shows an example of an embodiment of a package of the present invention, wherein 1 is a base, 1a is a projection for mounting the optical semiconductor element 8, 2 is a side wall of the base 1, and 2a is a penetrating base 1. The hole 3, 3 is a cover, 4 is an external lead terminal, 5 is a bonding wire as an electrical connection means, 6 is a metal member, 6b is a translucent member, 7 is an optical fiber, and 8 is an optical semiconductor element. The base 1 for mounting and housing the optical semiconductor element 8 on the bottom surface of the concave portion 1b formed on the upper surface basically forms a container for housing the optical semiconductor element 8 inside.
[0020]
The package of the present invention is formed from a base 1 having a convex portion 1a on which an optical semiconductor element 8 is mounted on the bottom surface of a concave portion 1b formed on the upper surface, and from the concave portion 1b to an outer surface of the base 1. A through-hole 2a, a cylindrical metal member 6 fitted in the through-hole 2a and having a protrusion 6d formed on the outer peripheral surface embedded in the base 1, and attached to the inside 6a of the metal member 6 Light-transmitting member 6b.
[0021]
The base 1 of the present invention is a support member for housing and supporting the optical semiconductor element 8, and has a convex portion 1a for mounting the optical semiconductor element 8 at the center of the bottom surface of the concave portion 1b on the upper surface. The optical semiconductor element 8 is mounted and fixed on the upper surface of the projection 1a with an adhesive or the like. The side wall 2 of the base 1 forms a space inside the side wall 2 for accommodating the optical semiconductor element 8. Alternatively, the side wall 2 of the base 1 may be a separate frame, and the frame may be joined to the outer periphery of the upper surface of the bottom plate of the base 1 so as to surround the protrusion 1a.
[0022]
The base 1 is made of an epoxy resin, an electrically insulating resin such as an engineering plastic made of PPS, LCP, or the like, a ceramic such as an alumina (Al 2 O 3 ) sintered body (alumina ceramic), or a composite of a ceramic and a resin. It consists of materials, glass, glass ceramics, metals and the like.
[0023]
The configuration in which the metal member 6 is fitted into the through hole 2a of the base 1 and the protrusion 6d formed on the outer peripheral surface is embedded in the base 1 is, for example, a transfer mold method or a base made of resin. This is achieved by previously placing the metal member 6 at a predetermined position of the mold when molding by injection molding or the like.
[0024]
A plurality of external lead terminals 4 whose both ends protrude inward and outward of the side wall portion 2 are provided on the side wall portion 2 of the base 1. The electrodes 8 are electrically connected to each other via bonding wires 5, and the portions of the external lead terminals 4 protruding outside the side wall 2 are electrically connected to an external electric circuit, so that the optical semiconductor element 8 is electrically connected. These electrodes are electrically connected to an external electric circuit via the external lead terminals 4.
[0025]
The external lead terminal 4 is made of a metal such as an iron (Fe) -nickel (Ni) -cobalt (Co) alloy or an Fe-Ni alloy. For example, the external lead terminal 4 is rolled into an ingot made of an Fe-Ni-Co alloy or the like. It is formed into a predetermined shape by applying a conventionally known metal working method such as a punching method. The attachment of the external lead terminal 4 to the side wall portion 2 is performed by setting the external lead terminal 4 at a predetermined position in a mold before forming the base 1 by the transfer molding method or the injection molding method. , Are integrally attached to predetermined positions of the side wall portion 2 with both ends protruding into and out of the side wall portion 2.
[0026]
The external lead terminal 4 has a predetermined thickness (about 1 to 20 μm) of a metal such as Ni or Au (gold) having good conductivity, excellent corrosion resistance, and good wettability with a brazing material by plating on the exposed surface. It is preferable that the external lead terminal 4 be oxidized and corroded effectively, and that the connection between the external lead terminal 4 and the bonding wire 5 and the connection between the external lead terminal 4 and the external electric circuit be reliable. Can be expensive.
[0027]
The translucent member 6b of the present invention is made of glass, sapphire, or the like, but may be made of resin as long as transparency and a certain degree of hardness can be ensured.
[0028]
The metal member 6 having the light transmitting member 6b attached to the inner side 6a is fixed in a state where the light transmitting member 6b is opposed to the light input / output portion of the optical semiconductor element 8, and the optical fiber 7 is attached to the outer end face thereof. Bonding with a resin adhesive, a brazing material such as Ag wax, Au-Sn wax, solder, welding method such as YAG laser welding, etc., so that the light input / output end of the device faces the optical semiconductor element 8 via a metal holder or the like. Is fixed. The metal member 6 is made of a metal such as an Fe-Ni-Co alloy or an Fe-Ni alloy. The metal member 6 is formed by subjecting the Fe-Ni-Co alloy or the like to a conventionally known metal working method such as a rolling method or a press forming method. , Are manufactured to have a desired shape.
[0029]
The metal member 6 has a cylindrical shape with a protrusion 6d formed on the outer peripheral surface. Thus, the volume of the metal member 6 can be reduced, and the stress due to the difference in thermal expansion between the metal member 6 and the metal member 6 applied to the light-transmitting member 6b can be minimized. Can be prevented. Further, since the protrusion 6d is embedded in the base 1, the adhesion between the metal member 6 and the base 1 can be improved, and the metal member 6 can be firmly fixed to the base 1. As described above, the airtightness at the portion of the light transmitting member 6b of the package is greatly improved.
[0030]
Preferably, as shown in FIG. 2, the metal member 6 has a thickness gradually reduced with an increase in the axial thickness of the protrusion 6 d from the central axis of the metal member 6. With this configuration, the stress due to the difference in thermal expansion between the metal member 6 and the base 1 is dispersed locally over the entire interface between the metal member 6 and the base 1 without being locally concentrated, and the translucent member is stressed by the stress applied to the metal member 6. Distortion of the optical signal 6b can be effectively suppressed, and as a result, the optical signal can be transmitted normally and stably without generating noise or the like in the optical signal transmitted through the translucent member 6b.
[0031]
In addition, in FIG. 2, the tip of the protrusion 6 d preferably has a curved surface such as an arc shape, and the stress applied to the metal member 6 can be effectively dispersed. In addition, the entire protrusion 6d may be curved, and in this case, the stress can be effectively dispersed.
[0032]
Furthermore, in FIG. 2, the protrusion 6 d has a shape protruding from the entire side surface of the cylindrical portion 6 c of the metal member 6. However, the protrusion 6 d protrudes from a part of the side surface of the cylindrical portion 6 c and approaches the end. Accordingly, the thickness may be gradually reduced. In this case, the adhesion between the metal member 6 and the base 1 is further improved, and the stress applied to the metal member 6 can be effectively dispersed.
[0033]
The attachment of the metal member 6 to which the translucent member 6b is attached to the side wall portion 2 is performed in advance when the base 1 is formed of a resin by the transfer molding method or the injection molding method. A metal member 6 having a light-transmitting member 6b attached thereto is set at a predetermined position in the mold, and the outer peripheral end of the metal member 6 is embedded in the inner peripheral surface of the through hole 2a of the side wall portion 2. It is done in.
[0034]
When the metal member 6 to which the translucent member 6b is attached is set in a mold, the position may be fixed by pressing the cylindrical portion 6c of the metal member 6 with the die. Since the mold does not directly contact the 6b, it is possible to prevent the light transmitting member 6b from being damaged such as a crack. The metal member 6 to which the translucent member 6b is attached is integrally attached to a predetermined position of the side wall 2 at the same time when the base 1 is molded. The positional accuracy of the light-transmitting member 6b is improved, and it is possible to prevent resin burrs from adhering to the surface of the light-transmitting member 6b during molding.
[0035]
Further, since the difference in thermal expansion between the metal member 6 made of a metal having a low coefficient of thermal expansion such as an Fe—Ni—Co alloy and the light transmitting member 6 b is small, the light transmitting member 6 b The occurrence of breakage such as cracks can be prevented. Furthermore, since the metal member 6 is installed with its outer peripheral end buried in the inner peripheral surface of the through hole 2a of the base 1, the airtightness of the translucent member 6b and the metal member 6 is greatly improved.
[0036]
Therefore, the container formed by the base 1 and the lid 3 is completely sealed, and the optical semiconductor element 8 accommodated in the container can be normally and stably operated for a long time.
[0037]
The thickness of the translucent member 6b in the optical axis direction is substantially the same as the thickness between both end surfaces (both main surfaces) in the optical axis direction of the metal member 6, or between the both end surfaces of the metal member 6. It is preferably smaller than the thickness. If the thickness of the translucent member 6b in the optical axis direction is larger than the thickness between both end surfaces of the metal member 6, when molding the base 1, resin burrs adhere to the translucent member 6b, The mold abuts on the transparent member 6b, and the translucent member 6b is easily damaged. As described above, the thickness of the metal member 6 in the optical axis direction is substantially the same as the thickness of the translucent member 6b, and is about 0.5 to 7 mm.
[0038]
The optical fiber 7 bonded to the metal member 6 to which the translucent member 6b is attached is for transmitting light emitted from the optical semiconductor element 8 to the outside or transmitting light from the outside to the optical semiconductor element 8. Functions as a light transmission path.
[0039]
Further, a lid 3 is attached to the upper surface of the side wall 2 via a sealing material made of a resin adhesive or the like, and the lid 1 closes the inside of the substrate 1 to form the base 1 and the lid 3. The optical semiconductor element 8 is accommodated in a container to be manufactured.
[0040]
In the present invention, it is preferable that the base 1 is made of resin, and the surface roughness of the protrusion 6d of the metal member 6 embedded in the base 1 is 1.6 to 25 μm in maximum height. By setting the maximum height (JIS B0601) of the surface roughness of the protrusion 6d to 1.6 to 25 μm, the metal member 6 can be firmly fixed to the base 1, and the optical semiconductor element 8 can be hermetically sealed. Further, even when pressure is applied to the metal member 6 due to a pressure difference between the inside and outside of the base 1, the metal member 6 can be prevented from being displaced from a predetermined position on the base 1. Therefore, the metal member 6 to which the translucent member 6b is attached and the optical semiconductor element 8 are more accurately opposed to each other, and the optical coupling efficiency between the translucent member 6b and the optical semiconductor element 8 is maintained at a high efficiency. it can.
[0041]
If the maximum height of the surface of the protrusion 6d of the metal member 6 is less than 1.6 μm, insufficient adhesion between the base 1 and the metal member 6 occurs, and poor airtightness is likely to occur. When the thickness exceeds 25 μm, the epoxy-based thermosetting resin becomes difficult to flow on the contrary, so that molding defects, voids and the like are generated, and airtight defects are liable to occur.
[0042]
Thus, the package according to the present invention includes the convex portion of the base 1 that fixes the metal member 6 to which the translucent member 6b is attached to the side wall portion 2 such that the translucent member 6b faces the optical semiconductor element 8. The optical semiconductor element 8 is placed and fixed on the upper surface of the semiconductor device 1a, and each electrode of the optical semiconductor element 8 is electrically connected to a predetermined external lead terminal 4 via a bonding wire 5, and the optical fiber 7 is bonded to the metal member 6. Thereafter, the lid 3 is attached to the upper surface of the side wall 2 via a sealing material, and the optical semiconductor element 8 is accommodated in a container formed of the base 1 and the lid 3, whereby light as a product is obtained. It becomes a semiconductor device.
[0043]
In this optical semiconductor device, a drive signal supplied from an external electric circuit is input to the optical semiconductor element 8 via the external lead terminal 4 to excite the optical semiconductor element 8 and transmit the excited light to the translucent member 6b. Or the light transmitted through the optical fiber 7 is received by the optical semiconductor element 8 through the translucent member 6b, and the optical semiconductor element 8 generates an electric signal corresponding to the received light. The optical semiconductor device operates by extracting the electric signal via the external lead terminal 4, and such an optical semiconductor device is used in the field of optical communication and the like.
[0044]
The present invention is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention.
[0045]
【The invention's effect】
The package for housing an optical semiconductor element of the present invention has a base provided with a convex portion on which the optical semiconductor element is mounted on the bottom surface of the concave portion formed on the upper surface, and a through hole formed from the concave portion to the outer surface of the base. A cylindrical metal member fitted with a hole, a projection formed on the outer peripheral surface and fitted in the through hole, and a translucent member attached inside the metal member Therefore, the airtightness at the portion of the light-transmitting member of the package for housing an optical semiconductor element is greatly improved. Further, for example, when the base is made of a resin, it is possible to prevent burrs of the resin from adhering to the light transmitting member when the base is molded, and the mold does not directly contact the light transmitting member at the time of molding. In addition, since the base made of resin is not in direct contact with the translucent member after manufacturing, it is possible to prevent the translucent member from being damaged such as cracks.
[0046]
In the package for housing an optical semiconductor element of the present invention, the metal member has a smaller thermal expansion difference between the metal member and the base since the axial thickness of the protrusion gradually decreases as the distance from the central axis of the metal member increases. The stress caused by the metal member is dispersed over the entire interface between the metal member and the base without locally concentrating, so that the light-transmitting member can be effectively prevented from being distorted by the stress applied to the metal member. As a result, the light-transmitting member The optical signal can be transmitted normally and stably without generating noise or the like in the optical signal transmitted through the optical signal.
[0047]
The optical semiconductor device of the present invention includes the optical semiconductor element housing package of the present invention, an optical semiconductor element mounted and fixed on the upper surface of the convex portion so as to be optically coupled to the translucent member, and the upper surface of the base. And a lid attached around the concave portion, the optical semiconductor device has excellent optical coupling efficiency and high airtight reliability using the optical semiconductor element housing package of the present invention.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating an example of an embodiment of an optical semiconductor element housing package of the present invention.
FIG. 2 is a sectional view showing another example of the embodiment of the package for housing an optical semiconductor element of the present invention.
FIG. 3 is a sectional view showing an example of a conventional package for housing an optical semiconductor element.
[Explanation of symbols]
1: Base 1a: convex portion 1b: concave portion 2a: through hole 3: lid 6: metal member 6b: translucent member 6d: protrusion 8: optical semiconductor element
