JP3615697B2

JP3615697B2 - Package for storing semiconductor elements

Info

Publication number: JP3615697B2
Application number: JP2000287455A
Authority: JP
Inventors: 信幸田中; 小林　　実
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2000-09-21
Filing date: 2000-09-21
Publication date: 2005-02-02
Anticipated expiration: 2020-09-21
Also published as: JP2002100693A

Description

【０００１】
【発明の属する技術分野】
本発明は、光通信やマイクロ波通信、ミリ波通信等の分野に用いられる各種半導体素子を収納する半導体素子収納用パッケージに関し、特にこの半導体素子収納用パッケージに設けられる入出力端子の改良に関するものである。
【０００２】
【従来の技術】
従来、マイクロ波帯域やミリ波帯域の高周波信号や、光信号により作動する各種半導体素子を収納する半導体素子収納用パッケージ（以下、半導体パッケージという）には、半導体素子と外部電気回路との高周波信号の入出力を行うための入出力端子が設けられている。この半導体パッケージのうち、光通信分野に用いられている光半導体パッケージについて、図４，図５に斜視図を示す。
【０００３】
これらの図に示すように、入出力端子１０４は、略長方形の平板部１０４ａの上面に略直方体の立壁部１０４ｂが積層されて成り、半導体素子１０９と外部電気回路（図示せず）との高周波信号の入出力を行う機能を有するとともに、光半導体パッケージの内外を遮断する機能を有する。
【０００４】
この平板部１０４ａは、アルミナ（Ａｌ_２Ｏ_３）セラミックス，窒化アルミニウム（ＡｌＮ）セラミックス，ムライト（３Ａｌ_２Ｏ_３・２ＳｉＯ_２）セラミックス等の誘電体から成り、その上面に、一長辺から対向する他の長辺にかけて、タングステン（Ｗ），モリブデン（Ｍｏ）−マンガン（Ｍｎ）等のメタライズ層から成る線路導体１０４ａ−Ａが形成されるとともに、下面には、その全面に線路導体１０４ａ−Ａと同様のメタライズ層から成る下部接地導体１０４ａ−Ｃが、また側面には、線路導体１０４ａ−Ａと平行である側面の全面に線路導体１０４ａ−Ａと同様のメタライズ層から成る側部接地導体１０４ａ−Ｂが形成される。
【０００５】
メタライズ層から成る、これら線路導体１０４ａ−Ａ，側部接地導体１０４ａ−Ｂ，下部接地導体１０４ａ−Ｃは、タングステン（Ｗ）、モリブデン（Ｍｏ）、マンガン（Ｍｎ）等で形成されている。例えばタングステン等の粉末に有機溶剤、溶媒を添加混合して得た金属ペーストを、平板部１０４ａ用のセラミックグリーンシートに、予め従来周知のスクリーン印刷法により所定パターンに印刷塗布しておき、焼成することにより形成される。
【０００６】
一方、立壁部１０４ｂは、平板部１０４ａと同様の誘電体から成り、その上面の全面に線路導体１０４ａ−Ａと同様のメタライズ層から成る上部接地導体１０４ｂ−Ａが、また側面には、平板部１０４ａの側部接地導体１０４ａ−Ｂに接する面の全面に線路導体１０４ａ−Ａと同様のメタライズ層から成る側面接地導体１０４ｂ−Ｂが形成される。
【０００７】
メタライズ層から成る、これら上部接地導体１０４ｂ−Ａ，側面接地導体１０４ｂ−Ｂは、平板部１０４ａに形成される線路導体１０４ａ−Ａ，側部接地導体１０４ａ−Ｂ，下部接地導体１０４ａ−Ｃと同様の方法により所定パターンに印刷塗布しておき焼成することにより形成される。
【０００８】
このように、入出力端子１０４は、これら上部接地導体１０４ｂ−Ａ、側面接地導体１０４ｂ−Ｂ、側部接地導体１０４ａ−Ｂ、下部接地導体１０４ａ−Ｃとで、線路導体１０４ａ−Ａを擬似同軸構造とし、高周波信号の入出力を良好なものとするとともに、枠体１０２に設けられた切欠部または貫通孔から成る取付部１０２ａに銀ロウ等のロウ材を介して接合されることにより、光半導体パッケージ内外を遮断する機能を有する。
【０００９】
この光半導体パッケージは、基体１０１と、その上面に接合された枠体１０２と、この枠体１０２の側部に嵌着された入出力端子１０４、枠体１０２の側部に接合された光ファイバ固定用の筒状の固定部材１０３と、枠体１０２上面に接合されたシールリング１０６とを具備している。
【００１０】
基体１０１は、半導体素子１０９を載置する載置部１０１ａを有し、半導体素子１０９の作動時に発する熱を外部に効率良く放散する機能を有する、銅（Ｃｕ）−タングステン（Ｗ）合金や鉄（Ｆｅ）−ニッケル（Ｎｉ）−コバルト（Ｃｏ）合金等の金属材料から成る。
【００１１】
枠体１０２は、基体１０１上面に載置部１０１ａを囲繞するように銀ロウ等のロウ材で接合され、側部に入出力端子１０４を嵌着する取付部１０２ａと、他の側部に光伝送路として機能する貫通孔１０２ｂとが形成されたものであり、銅（Ｃｕ）−タングステン（Ｗ）合金や鉄（Ｆｅ）−ニッケル（Ｎｉ）−コバルト（Ｃｏ）合金等の金属材料から成る。
【００１２】
入出力端子１０４は、取付部１０２ａに銀ロウ等のロウ材で嵌着される。
【００１３】
固定部材１０３は、その一面が貫通孔１０２ｂの開口を囲むように銀ロウ等のロウ材で接合され、もう片面には光ファイバ１０８を樹脂等の接着剤で取着した金属ホルダ１０７が金（Ａｕ）−錫（Ｓｎ）等の低融点ロウ材で接合される。
【００１４】
リード端子１０５は、入出力端子１０４の線路導体１０４ａ−Ａに銀ロウ等のロウ材を介して接合され、外部電気回路と入出力端子１０４との高周波信号の入出力を行うものであり、鉄（Ｆｅ）−ニッケル（Ｎｉ）−コバルト（Ｃｏ）合金等の金属材料から成る。
【００１５】
シールリング１０６は、枠体１０２上面に銀ロウ等のロウ材で接合され入出力端子１０４を挟持するとともに、上面に蓋体（図示せず）をシーム溶接等により接合するための媒体として機能する。
【００１６】
このような光半導体パッケージに、光半導体素子としての半導体素子１０９を載置部１０１ａにＳｎ−Ｐｂ半田等の低融点ロウ材で載置固定するとともに、線路導体１０４ａ−Ａと半導体素子１０９とをボンディングワイヤ（図示せず）で電気的に接続し、さらに固定部材１０３に、光ファイバ１０８を樹脂等の接着剤で取着した金属ホルダ１０７を、金（Ａｕ）−錫（Ｓｎ）等の低融点ロウ材で接合した後、シールリング１０６上面に蓋体（図示せず）をシーム溶接等により接合することにより、製品としての光半導体装置となる。
【００１７】
このような光半導体装置は、例えば外部電気回路から供給される駆動信号によって光半導体素子１０９を光励起させ、励起したレーザ光等の光を光ファイバ１０８に授受させるとともに、光ファイバ１０８内を伝送させることにより、大容量の情報を高速に伝送できる光電変換装置として機能するとともに、光通信分野等に多く用いられる。
【００１８】
【発明が解決しようとする課題】
しかしながら、上記従来の入出力端子１０４において、これを取付部１０２ａに銀ロウ等のロウ材で嵌着させた際に、このロウ材が、側部接地導体１０４ａ−Ｂと金属材料から成る枠体１０２内壁面とのわずかな隙間を埋めるように流れて、その隙間にロウ材溜まりを発生させる場合があった。その場合、ロウ材と平板部１０４ａの半導体パッケージ内に位置する部位との間、およびロウ材と枠体１０２内壁面との間のそれぞれの間の熱膨張差により、最も弾性の低い平板部１０４ａに熱歪みが発生し、クラックが発生するという問題点を有していた。
【００１９】
なお、この問題点を解決する方法として、側部接地導体１０４ａ−Ｂと枠体１０２内壁面との隙間を十分に大きくすることが考えられ、この場合、枠体１０２を大きくするか、または入出力端子１０４を小さくするかのいずれかとなる。枠体１０２を大きくした場合、半導体パッケージを大型化することになり、近時の半導体パッケージの小型軽量化の動向から外れることとなる。一方、入出力端子１０４を小さくした場合、これに形成される線路導体１０４ａ−Ａの幅も狭くしなければならず、リード端子１０５のロウ材による接合が脆弱なものとなり、外部電気回路と入出力端子１０４との高周波信号の損失が増大したり、リード端子１０５が外れて高周波信号の入出力ができなくなる場合がある。
【００２０】
また、平板部１０４ａの、線路導体１０４ａ−Ａと平行である側面のロウ材溜まりが発生する部位のみに、側部接地導体１０４ａ−Ｂを形成しないことにより、ロウ材がこの部位に流れてこないようにすることも考えられるが、メタライズ層の形成のために印刷工程が必要になり作業効率が非常に低下する。
【００２１】
従って、本発明は上記問題点に鑑み完成されたもので、その目的は、半導体パッケージに嵌着される入出力端子に発生するクラックを有効に防止するとともに、半導体パッケージが大型化することや、高周波信号の入出力が損なわれることを防止することにある。
【００２２】
【課題を解決するための手段】
本発明の半導体パッケージは、上面に半導体素子が載置される載置部を有する基体と、該基体上面に前記載置部を囲繞するように取着された金属製の枠体と、該枠体を貫通してまたは切り欠いて形成された入出力端子の取付部と、上面に一辺から対向する他辺にかけて形成された線路導体を有する誘電体から成る平板部および該平板部の上面に前記線路導体を間に挟んで接合された誘電体から成る立壁部を有するとともに前記取付部に嵌着接合された入出力端子とを具備する半導体素子収納用パッケージにおいて、前記平板部の側面の前記枠体内側の部位に、前記立壁部の前記枠体内側の側面と略面一に切り欠かれた面を有する切欠部が形成されており、前記平板部の側面の前記切欠部以外の部分にメタライズ層が形成されていることを特徴とする。
【００２３】
本発明は、上記の構成により、入出力端子を取付部に銀ロウ等のロウ材で嵌着させた際に、このロウ材が、平板部の側部接地導体と金属材料から成る枠体の内壁面とのわずかな隙間を埋めるように流れることはない。即ち、その隙間にロウ材溜まりを発生させることはない。そのため、ロウ材と平板部の枠体に接合される側面の枠体内側に位置する部位との間、およびロウ材と枠体の内壁面との間のそれぞれの間の熱膨張差により、最も弾性の低い平板部に熱歪みによるクラックを発生させることがなくなる。従って、半導体パッケージが大型化することや、高周波信号の入出力が損なわれることを防止でき、半導体素子を長期間にわたり正常かつ安定に作動させ得る。
【００２４】
また従来、平板部の上面においてロウ材は平板部と立壁部の境界部にメニスカスを形成し易いためその境界部に沿って濡れ易く、その結果ロウ材が平板部の枠体に接合される側面から平板部の上面に侵入していたが、立壁部の枠体内側の側面と略面一に切り欠かれた面を有する切欠部が形成されていることにより、ロウ材が上記境界部にメニスカスを形成せず、平板部の上面に侵入することがなくなる。従って、平板部の上面に侵入したロウ材により、境界部付近にクラックが発生するのを防ぐことができる。
【００２５】
本発明において、好ましくは、前記切り欠かれた面の長さが０．１ｍｍ以上であることを特徴とする。
【００２６】
上記の構成により、ロウ材溜まりが発生するのを有効に防止し、またロウ材が平板部と立壁部の境界部に沿って濡れることを有効に防止することができる。
【００２７】
【発明の実施の形態】
本発明の光半導体パッケージについて以下に説明する。図１は本発明の光半導体パッケージの斜視図、図２はこの半導体パッケージに設けられる入出力端子の拡大斜視図を示し、これらの図において、１は基体、２は枠体、３は光ファイバが取着された金属ホルダ７を固定する筒状の固定部材、４は入出力端子、６はシールリングである。これら基体１と枠体２と固定部材３と入出力端子４とシールリング６とで、内部にＬＤ，ＰＤ等の光半導体素子としての半導体素子９を収納し、シールリング６上面に蓋体を取着することにより容器が構成される。
【００２８】
基体１は、その上面に半導体素子９を載置する載置部１ａを有し、半導体素子９を支持する支持部材として機能するとともに、半導体素子９の作動時に発する熱を外部に効率良く放散する機能を有する。
【００２９】
この基体１は、その形状は略直方体であり、銅（Ｃｕ）−タングステン（Ｗ）合金やＦｅ−Ｎｉ−Ｃｏ合金等の金属材料から成る。また、その製作は合金のインゴットに圧延加工やプレス加工等の金属加工を施すことにより所定の形状に成形される。
【００３０】
なお、この基体１は、その表面に耐蝕性に優れかつロウ材との濡れ性に優れる金属、具体的には厚さ０．５〜９μｍのＮｉ層と、厚さ０．５〜５μｍのＡｕ層とを順次メッキ法により被着させておくと、基体１が酸化腐食するのを有効に防止できるとともに、基体１上面に半導体素子９を強固に接着固定できる。従って、基体１表面には０．５〜９μｍのＮｉ層や厚さ０．５〜５μｍのＡｕ層等の金属層をメッキ法により被着させておくことが好ましい。
【００３１】
また、この基体１の上面には、載置部１ａを囲繞するように、側部に入出力端子４を嵌着するための貫通孔または切欠部から成る取付部２ａと、他の側部に光伝送路として機能する貫通孔２ｂとが形成された枠体２が、銀ロウ等のロウ材で接合されており、この枠体２の内側に半導体素子９を収納するための空所が形成される。
【００３２】
この枠体２は、基体１と同様の金属材料から成り、その製作は基体１と同様の加工法により、側部に取付部２ａを、他の側部に貫通孔２ｂを有するような形状に加工される。
【００３３】
なお、枠体２の基体１への接合は、基体１上面と枠体２下面とを、基体１上面に敷設した適度なボリュームを有するプリフォームとされた銀ロウ等のロウ材を介して接合される。さらに、枠体２表面には、基体１と同様に０．５〜９μｍのＮｉ層や厚さ０．５〜５μｍのＡｕ層等の金属層をメッキ法により被着させておくと良い。
【００３４】
また、この枠体２の取付部２ａには、半導体素子９と外部電気回路（図示せず）との高周波信号の入出力を行う機能を有するとともに、光半導体パッケージの内外部を遮断する機能を有する入出力端子４が、これに設けられているメタライズ層を介して銀ロウ等のロウ材で接合される。
【００３５】
この入出力端子４は、略直方体で板状の平板部４ａの上面に、略直方体で横倒しにされた四角柱状の立壁部４ｂが積層されて成る。
【００３６】
この平板部４ａは、アルミナ（Ａｌ_２Ｏ_３）セラミックス，窒化アルミニウム（ＡｌＮ）セラミックス，ムライト（３Ａｌ_２Ｏ_３・２ＳｉＯ_２）セラミックス等の誘電体から成る。そして、平板部４ａの上面には、長辺の１辺から対向する他辺にかけて、Ｗ，Ｍｏ−Ｍｎ等のメタライズ層から成る線路導体４ａ−Ａが形成される。平板部４ａの下面には、全面に線路導体４ａ−Ａと同様のメタライズ層から成る下部接地導体４ａ−Ｃが形成され、また側面には、線路導体４ａ−Ａと平行となる側面Ｈ（図２）の一部、即ち側面Ｈの平板部４ａの枠体２内側に位置する部位を切り欠いて設けられた切欠部４ｃ以外の部分に、線路導体４ａ−Ａと同様のメタライズ層から成る側部接地導体４ａ−Ｂが形成される。
【００３７】
この切欠部４ｃは、入出力端子４を取付部２ａに銀ロウ等のロウ材で嵌着させた際に、このロウ材が、側部接地導体４ａ−Ｂと金属材料から成る枠体２内壁面とのわずかな隙間を埋めるように流れ込むのを有効に防止できる。なお、この隙間は、側面Ｈが２つあるため入出力端子４と枠体２との間に２箇所有る。即ち、切欠部４ｃを設けることにより、側部接地導体４ａ−Ｂと枠体２内壁面とのわずかな隙間にロウ材溜まりを発生させることはない。そのため、ロウ材と平板部４ａの枠体２内側に位置する部位との間、およびロウ材と枠体２内壁面との間のそれぞれの間の熱膨張差により、最も弾性の低い平板部４ａに熱歪みや、クラックを発生させることはない。
【００３８】
なお、この切欠部４ｃは、平板部４ａの枠体２に接合される側面の枠体２内側に、立壁部４ｂの枠体２内側の側面と略面一に切り欠かれた面Ｐ（図２）を有する切欠部４ｃであり、好ましくは面Ｐの長さが０．１ｍｍ以上であることがよい。この切欠部４ｃは、平板部４ａに少なくとも１箇所設けられていれば良く、２箇所とも０．１ｍｍ未満で形成した場合、側部接地導体４ａ−Ｂと枠体２内壁面とのわずかな隙間に、２箇所ともロウ材溜まりが発生しやすくなる傾向にある。そのため、ロウ材と平板部４ａの枠体２内側に位置する部位との間、およびロウ材と枠体２内壁面との間のそれぞれの間の熱膨張差により発生する熱歪みが大きなものとなり、その結果平板部４ａに大きな圧縮熱応力が印加され、クラックを発生させ易くなる。
【００３９】
一方、１箇所に０．１ｍｍ以上の切欠部４ｃを、もう１個所には切欠部４ｃを設けていない場合、切欠部４ｃを設けていない部位にロウ材溜まりが発生しても、もう片方の部位にはロウ材溜まりは発生しない。この場合、平板部４ａには全くクラックが発生せず、この場合に平板部４ａに印加される圧縮熱応力の大きさ程度では、平板部４ａにクラックは発生しないことが分かった。
【００４０】
従って、切欠部４ｃは、平板部４ａの側面Ｈの枠体２内側に位置する部位において、立壁部４ｂの枠体２内側の側面と略面一に切り欠かれた面Ｐを有しており、その面Ｐの長さを０．１ｍｍ以上とし、そのような切欠部４ｃを少なくとも１箇所設ることが良い。
【００４１】
なお、切欠部４ｃの内周面、即ち平板部４ａの側面Ｈを切り欠くことにより形成される面は、Ｒ面やＣ面等種々の形状とし得る。また切欠部４ｃは、図２のように、必ずしも側面Ｈの平板部４ａの枠体２内側の全面を切り欠くようにして形成しなくてもよく、面Ｐを含み平面視形状が半円状、長円状、凹状等の形状の切欠部４ｃとしてもよい。その場合、切欠部４ｃの線路導体４ａ−Ａ方向の長さは、側面Ｈの平板部４ａの枠体２内側の全面の長さの１／３以上あればよく、これによりロウ材溜まりの形成を有効に防ぐことができる。
【００４２】
また、この切欠部４ｃは、半導体パッケージが光半導体パッケージの場合、入出力端子４の、光ファイバ８等を固定する固定部材３が接合される枠体２側部に近い側の側部に、設けられることが好ましい。即ち、切欠部４ｃが固定部材３が接合される側部に近い側部に設けられていない場合、半導体素子９と光ファイバ８との光軸を調整した後、半導体素子９を作動させた際、半導体素子９の発した熱が枠体２に伝わることにより、ロウ材と枠体２内壁面との間の残留熱応力と合わさって、枠体２に大きな熱歪みが発生することになる。そのため、光ファイバ８と半導体素子９との光軸がずれることとなり、半導体素子９の作動性を損なわせる。従って、切欠部４ｃは、半導体パッケージが光半導体パッケージの場合、入出力端子４の固定部材３が接合される枠体２側部に近い側の側部に設けられることが好ましい。
【００４３】
なお、平板部４ａと立壁部４ｂとの積層界面の周辺部、即ち平板部４ａの枠体２に接合される側面の枠体２内側または枠体２外側に余分なメタライズ層が形成された場合、線路導体４ａ−Ａと余分なメタライズ層との間の容量値が高くなり、高周波信号のインピーダンス不整合による反射等の伝送特性の低下を発生させる場合がある。従って、余分なメタライズ層が全く形成されないように、平板部４ａの枠体２に接合される側面の枠体２内側の２箇所および枠体２外側の２箇所の４箇所に、切欠部４ａを設けることが良い。
【００４４】
さらに、平板部４ａの枠体２に接合される側面の枠体２内側または枠体２外側に余分なメタライズ層が形成された場合、平板部４ａの上面における平板部４ａと立壁部４ｂとの境界部にロウ材がメニスカスを形成して濡れ易くなり、境界部に侵入する場合がある。その場合、境界部に侵入したロウ材が、線路導体４ａ−Ａとの間で浮遊容量を発生させ、高周波信号の伝送特性を劣化させることとなる。従って、このような伝送特性の劣化を防ぐために、平板部４ａの枠体２に接合される側面の枠体２内側の２箇所および枠体２外側の２箇所の４箇所に、切欠部４ａを設けることが良い。
【００４５】
このような切欠部４ｃが設けられた平板部４ａの線路導体４ａ−Ａ、側部接地導体４ａ−Ｂおよび下部接地導体４ａ−Ｃは、Ｗ，Ｍｏ，Ｍｎ等のメタライズ層で形成されており、例えばＷ等の粉末に有機溶剤、溶媒を添加混合して得た金属ペーストを、平板部４ａ用のセラミックグリーンシートに、予め従来周知のスクリーン印刷法により所定パターンに印刷塗布しておき、焼成することにより形成される。
【００４６】
また、平板部４ａの上面には立壁部４ｂが積層される。この立壁部４ｂは、平板部４ａと同様の誘電体から成り、その上面の全面に線路導体４ａ−Ａと同様のメタライズ層から成る上部接地導体４ｂ−Ａが、また平板部４ａの側面Ｈの側部接地導体４ａ−Ｂに略面一で連続する側面の全面に、線路導体１０４ａ−Ａと同様のメタライズ層から成る側面接地導体４ｂ−Ｂが形成されている。
【００４７】
立壁部４ｂの上部接地導体４ｂ−Ａ、側面接地導体４ｂ−Ｂは、平板部４ａに形成される線路導体４ａ−Ａ、側部接地導体４ａ−Ｂおよび下部接地導体４ａ−Ｃと同様の方法により所定パターンに印刷塗布しておき、焼成することにより形成される。
【００４８】
このように、入出力端子４は、これら上部接地導体４ｂ−Ａ、側面接地導体４ｂ−Ｂ、側部接地導体４ａ−Ｂおよび下部接地導体４ａ−Ｃとで、線路導体４ａ−Ａを擬似同軸構造とし、高周波信号の入出力を良好なものとするとともに、枠体２に設けられた切欠部または貫通孔から成る取付部２ａに銀ロウ等のロウ材を介して接合されることにより、光半導体パッケージ内外を遮断する機能を有する。さらには、切欠部４ｃにより、ロウ材と平板部４ａの枠体２内側に位置する部位との間、およびロウ材と枠体２内壁面との間のそれぞれの間の熱膨張差により、最も弾性の低い平板部４ａに熱歪みや、クラックを発生させることはない。また、この切欠部４ｃは、半導体パッケージが光半導体パッケージの場合、入出力端子４の、光ファイバ８等を固定する固定部材３が接合される枠体２側部に近い側の側部に設けられることが、上述したように好ましい。
【００４９】
この入出力端子４の線路導体４ａ−Ａの枠体２外部に導出される部位には、外部電気回路と入出力端子１０４との高周波信号の入出力を行い、Ｆｅ−Ｎｉ−Ｃｏ合金等の金属材料から成るリード端子５が銀ロウ等のロウ材で接合される。
【００５０】
また、この入出力端子４が側部に嵌着される枠体２の他の側部には貫通孔２ｂが形成されており、一端面が貫通孔２ｂの開口を囲むように銀ロウ等のロウ材で接合され、他方の端面には光ファイバ８を樹脂等の接着剤で取着した金属ホルダ７がＡｕ−Ｓｎ等の低融点ロウ材で接合される固定部材３が設けられる。この固定部材３は、基体１や枠体２と同様の材料を同様の加工法で所望の形状に加工作製されるとともに、その表面に０．５〜９μｍのＮｉ層や０．５〜５μｍのＡｕ層等の金属層をメッキ法により被着させておくと良い。
【００５１】
このように入出力端子４および固定部材３が取着される枠体２上面にはシールリング６が銀ロウ等のロウ材で接合される。このシールリング６は、枠体２上面に銀ロウ等のロウ材で接合されて入出力端子４を挟持するとともに、その上面に、半導体素子９を封止するための蓋体をシーム溶接等により接合するための媒体として機能する。
【００５２】
本発明の半導体パッケージとしての光半導体パッケージは、金属材料から成る基体１と、その上面に半導体素子９の載置部１ａを囲繞するように接合され、取付部２ａ、貫通孔２ｂを有する金属材料から成る枠体２と、この取付部２ａに銀ロウ等のロウ材で接合され、ロウ材と平板部４ａの枠体２内側に位置する部位との間、およびロウ材と枠体２内壁面との間のそれぞれの間の熱膨張差により、平板部４ａに熱歪みや、クラックが発生するのを有効に防止できる入出力端子４とを具備している。この入出力端子４は、平板部４ａの枠体２内側に位置する部位の側面を切り欠いて設けられた切欠部４ｃが少なくとも１箇所形成されている。
【００５３】
このような光半導体パッケージに、光半導体素子としての半導体素子９を載置部１ａにＳｎ−Ｐｂ半田等の低融点ロウ材で載置固定するとともに、線路導体４ａ−Ａと半導体素子９とをボンディングワイヤで電気的に接続し、さらに固定部材３に、光ファイバ８を樹脂等の接着剤で取着した金属ホルダ７を、Ａｕ−Ｓｎ等の低融点ロウ材で接合した後、シールリング６上面に蓋体をシーム溶接等により接合することにより、製品としての光半導体装置となる。
【００５４】
この光半導体装置は、例えば外部電気回路から供給される駆動信号によって光半導体素子９を光励起させ、励起したレーザ光等の光を光ファイバ８に授受させるとともに、光ファイバ８内を伝送させることにより、大容量の情報を高速に伝送できる光電変換装置として機能するものであり、光通信分野等に多く用いられる。
【００５５】
かくして、本発明は、半導体パッケージに嵌着される入出力端子に発生するクラックを有効に防止する構造であるため、半導体パッケージを大型化しなければならなかったり、高周波信号の入出力が損なわれる等の問題を解消できる。その結果、半導体素子を長期間にわたり、正常かつ安定に作動させ得る。
【００５６】
なお、本発明は、上記実施の形態に限定されず、本発明の要旨を逸脱しない範囲内において種々の変更を行うことは何等支障ない。例えば、図３に示すように、切欠部４ｃは平板部４ａの側面の枠体２内側に位置する部位のみならず、平板部４ａの側面の枠体２外側に位置する部位も切り欠いても良く、この場合、平板部４ａの側面の枠体２外側に位置する部位と枠体２外側面とが交差する部位にもロウ材溜まりが発生することはない。その結果、入出力端子４を枠体２の取付部２ａに嵌着させた際に発生する熱歪みを非常に小さいものとでき、それらの接合をより強固なものとできる。
【００５７】
【発明の効果】
本発明は、誘電体から成る平板部と誘電体から成る立壁部とから構成された入出力端子を具備する半導体パッケージにおいて、平板部の側面の枠体内側の部位に、立壁部の枠体内側の側面と略面一に切り欠かれた面を有する切欠部が形成されており、平板部の側面の切欠部以外の部分にメタライズ層が形成されていることにより、この入出力端子を半導体パッケージにロウ材を介して設けた際、ロウ材と平板部の側面の枠体内側に位置する部位との間、およびロウ材と枠体内壁面との間のそれぞれの間の熱膨張差により、最も弾性の低い平板部に熱歪みや、クラックを発生させることはない。その結果、半導体パッケージが大型化することや、高周波信号の入出力が損なわれることを防止でき、半導体素子を長期間にわたり正常かつ安定に作動させ得る。
【００５８】
また従来、ロウ材は平板部上面において平板部と立壁部の境界部にメニスカスを形成し易いためその境界部に沿って濡れ易く、その結果ロウ材が平板部の側面から平板部の上面に侵入していたが、立壁部の枠体内側の側面と略面一に切り欠かれた面を有する切欠部が形成されていることにより、ロウ材が上記境界部にメニスカスを形成せず、平板部の上面に侵入することがなくなる。従って、平板部の上面に侵入したロウ材により、境界部付近にクラックが発生するのを防ぐことができる。
【００５９】
また本発明は、好ましくは、立壁部の枠体内側の側面と略面一に切り欠かれた面の長さが０．１ｍｍ以上であることにより、ロウ材溜まりの形成を有効に防止し、またロウ材が平板部と立壁部の境界部に沿って濡れることを有効に防止することができる。
【図面の簡単な説明】
【図１】本発明の半導体パッケージの一実施形態を示す斜視図である。
【図２】図１の半導体パッケージ用の入出力端子の拡大斜視図である。
【図３】本発明の入出力端子の他の実施形態を示す拡大斜視図である。
【図４】従来の半導体パッケージの斜視図である。
【図５】図４の半導体パッケージ用の入出力端子である。
【符号の説明】
１：基体
１ａ：載置部
２：枠体
２ａ：取付部
４：入出力端子
４ａ：平板部
４ｂ：立壁部
４ｃ：切欠部
９：半導体素子[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor element storage package for storing various semiconductor elements used in fields such as optical communication, microwave communication, and millimeter wave communication, and more particularly to improvement of input / output terminals provided in the semiconductor element storage package. It is.
[0002]
[Prior art]
Conventionally, a high frequency signal in a microwave band or a millimeter wave band, or a semiconductor element storage package (hereinafter referred to as a semiconductor package) that stores various semiconductor elements that are operated by an optical signal, is a high frequency signal between a semiconductor element and an external electric circuit. An input / output terminal is provided for performing input / output. Among these semiconductor packages, FIGS. 4 and 5 are perspective views of optical semiconductor packages used in the optical communication field.
[0003]
As shown in these drawings, the input / output terminal 104 is formed by laminating a substantially rectangular parallelepiped wall 104b on the upper surface of a substantially rectangular flat plate portion 104a, and a high frequency between the semiconductor element 109 and an external electric circuit (not shown). It has a function of inputting and outputting signals and a function of blocking the inside and outside of the optical semiconductor package.
[0004]
The flat plate portion 104a is made of alumina (Al ₂ O ₃ ) Ceramics, aluminum nitride (AlN) ceramics, mullite (3Al ₂ O ₃ ・ 2SiO ₂ ) A line conductor 104a-A made of a dielectric material such as ceramics and having a metallized layer such as tungsten (W), molybdenum (Mo) -manganese (Mn) on the upper surface from one long side to the other long side opposite to the upper surface. The lower ground conductor 104a-C made of a metallized layer similar to the line conductor 104a-A is formed on the entire bottom surface, and the entire side surface parallel to the line conductor 104a-A is formed on the side surface. A side ground conductor 104a-B made of a metallized layer similar to the line conductor 104a-A is formed.
[0005]
These line conductors 104a-A, side ground conductors 104a-B, and lower ground conductors 104a-C made of a metallized layer are made of tungsten (W), molybdenum (Mo), manganese (Mn), or the like. For example, a metal paste obtained by adding and mixing an organic solvent and a solvent to a powder such as tungsten is preliminarily printed on a ceramic green sheet for the flat plate portion 104a in a predetermined pattern by a conventionally known screen printing method, and is fired. Is formed.
[0006]
On the other hand, the standing wall portion 104b is made of the same dielectric as the flat plate portion 104a, the upper ground conductor 104b-A made of the same metallized layer as the line conductor 104a-A is formed on the entire upper surface, and the flat plate portion is formed on the side surface. A side ground conductor 104b-B made of a metallized layer similar to the line conductor 104a-A is formed on the entire surface of the surface 104a in contact with the side ground conductor 104a-B.
[0007]
These upper ground conductor 104b-A and side ground conductor 104b-B made of a metallized layer are the same as the line conductor 104a-A, side ground conductor 104a-B, and lower ground conductor 104a-C formed on the flat plate portion 104a. It is formed by printing and applying to a predetermined pattern by the method and baking.
[0008]
As described above, the input / output terminal 104 includes the upper ground conductor 104b-A, the side ground conductor 104b-B, the side ground conductor 104a-B, and the lower ground conductor 104a-C, and the line conductor 104a-A is pseudo-coaxial. With the structure, the input / output of high-frequency signals is good, and it is joined to a mounting portion 102a formed of a notch or a through-hole provided in the frame body 102 via a brazing material such as silver brazing. It has a function of blocking the inside and outside of the semiconductor package.
[0009]
The optical semiconductor package includes a base body 101, a frame body 102 bonded to the upper surface thereof, an input / output terminal 104 fitted to a side portion of the frame body 102, and an optical fiber bonded to a side portion of the frame body 102. A cylindrical fixing member 103 for fixing and a seal ring 106 joined to the upper surface of the frame body 102 are provided.
[0010]
The base 101 has a mounting portion 101a for mounting the semiconductor element 109, and has a function of efficiently dissipating heat generated when the semiconductor element 109 is operated to the outside, such as a copper (Cu) -tungsten (W) alloy or iron. It consists of metal materials, such as (Fe) -nickel (Ni) -cobalt (Co) alloy.
[0011]
The frame body 102 is joined to the upper surface of the base body 101 with a brazing material such as silver brazing so as to surround the mounting portion 101a, and the mounting portion 102a in which the input / output terminal 104 is fitted to the side portion and the optical portion on the other side portion. A through hole 102b that functions as a transmission path is formed, and is made of a metal material such as a copper (Cu) -tungsten (W) alloy or an iron (Fe) -nickel (Ni) -cobalt (Co) alloy.
[0012]
The input / output terminal 104 is fitted to the mounting portion 102a with a brazing material such as silver brazing.
[0013]
The fixing member 103 is joined with a brazing material such as silver brazing so that one surface surrounds the opening of the through-hole 102b, and a metal holder 107 having an optical fiber 108 attached with an adhesive such as a resin is gold (on the other surface) Joined with a low melting point brazing material such as Au) -tin (Sn).
[0014]
The lead terminal 105 is joined to the line conductor 104a-A of the input / output terminal 104 via a brazing material such as silver solder, and performs input / output of high frequency signals between the external electric circuit and the input / output terminal 104. It is made of a metal material such as (Fe) -nickel (Ni) -cobalt (Co) alloy.
[0015]
The seal ring 106 is joined to the upper surface of the frame body 102 by a brazing material such as silver solder, and sandwiches the input / output terminal 104, and functions as a medium for joining a lid (not shown) to the upper surface by seam welding or the like. .
[0016]
In such an optical semiconductor package, the semiconductor element 109 as an optical semiconductor element is mounted and fixed to the mounting portion 101a with a low melting point solder such as Sn-Pb solder, and the line conductor 104a-A and the semiconductor element 109 are fixed. A metal holder 107, which is electrically connected with a bonding wire (not shown), and further has an optical fiber 108 attached to the fixing member 103 with an adhesive such as a resin, is bonded to a low metal such as gold (Au) -tin (Sn). After joining with the melting point brazing material, a lid (not shown) is joined to the upper surface of the seal ring 106 by seam welding or the like, so that an optical semiconductor device as a product is obtained.
[0017]
Such an optical semiconductor device, for example, optically excites the optical semiconductor element 109 by a drive signal supplied from an external electric circuit, transmits and receives the excited light such as laser light to the optical fiber 108, and transmits the optical fiber 108. As a result, it functions as a photoelectric conversion device capable of transmitting a large amount of information at high speed and is often used in the field of optical communication.
[0018]
[Problems to be solved by the invention]
However, when the conventional input / output terminal 104 is fitted to the mounting portion 102a with a brazing material such as silver brazing, the brazing material is composed of a side ground conductor 104a-B and a frame made of a metal material. In some cases, it flows so as to fill a slight gap with the inner wall surface 102, and a brazing material pool is generated in the gap. In that case, the flat plate portion 104a having the lowest elasticity is caused by the difference in thermal expansion between the brazing material and the portion of the flat plate portion 104a located in the semiconductor package and between the brazing material and the inner wall surface of the frame 102. In this case, there is a problem in that thermal distortion occurs and cracks occur.
[0019]
As a method for solving this problem, it is conceivable to sufficiently increase the gap between the side ground conductors 104a-B and the inner wall surface of the frame 102. In this case, the frame 102 is enlarged or inserted. Either the output terminal 104 is reduced. When the frame body 102 is enlarged, the semiconductor package is increased in size and deviated from the recent trend of reducing the size and weight of the semiconductor package. On the other hand, when the input / output terminal 104 is made small, the width of the line conductor 104a-A formed on the input / output terminal 104 must be narrowed, and the joining of the lead terminal 105 with the brazing material becomes fragile, so In some cases, the loss of the high-frequency signal with the output terminal 104 increases, or the lead terminal 105 is detached and input / output of the high-frequency signal becomes impossible.
[0020]
Further, the brazing material does not flow into this part by not forming the side ground conductors 104a-B only in the part where the brazing material pool on the side surface parallel to the line conductor 104a-A of the flat plate part 104a occurs. Although it is conceivable that a printing process is required for forming the metallized layer, the working efficiency is greatly reduced.
[0021]
Therefore, the present invention has been completed in view of the above problems, and its purpose is to effectively prevent cracks occurring in the input / output terminals fitted to the semiconductor package, and to increase the size of the semiconductor package, This is to prevent the high-frequency signal input / output from being damaged.
[0022]
[Means for Solving the Problems]
The semiconductor package of the present invention includes a base having a mounting portion on which a semiconductor element is mounted on the upper surface, a metal frame attached on the upper surface of the base so as to surround the mounting portion, and the frame A flat plate portion made of a dielectric having an input / output terminal mounting portion formed through the body or cut out, a line conductor formed on the upper surface from one side to the opposite side, and the upper surface of the flat plate portion; In a package for housing a semiconductor element, comprising a standing wall portion made of a dielectric material joined with a line conductor interposed therebetween and an input / output terminal fitted and joined to the mounting portion, the frame on the side surface of the flat plate portion A cutout portion having a surface that is substantially flush with the side surface of the frame body inside the standing wall portion is formed in a portion inside the body. And a metallized layer is formed on a portion of the side surface of the flat plate portion other than the notch portion. It is characterized by being.
[0023]
According to the present invention, when the input / output terminal is fitted to the mounting portion with a brazing material such as silver brazing, the brazing material has a frame body made of a side ground conductor of the flat plate portion and a metal material. It does not flow so as to fill a slight gap with the inner wall surface. That is, no brazing material pool is generated in the gap. Therefore, due to the difference in thermal expansion between the brazing material and the portion located inside the frame on the side surface joined to the frame of the flat plate portion, and between the brazing material and the inner wall surface of the frame, Cracks due to thermal strain are not generated in the flat plate portion having low elasticity. Therefore, it is possible to prevent the semiconductor package from becoming large and the input / output of the high frequency signal from being damaged, and the semiconductor element can be operated normally and stably over a long period of time.
[0024]
Conventionally, since the brazing material easily forms a meniscus at the boundary between the flat plate portion and the standing wall portion on the upper surface of the flat plate portion, the brazing material easily wets along the boundary portion, and as a result, the side surface where the brazing material is joined to the frame of the flat plate portion. However, the brazing material is formed at the boundary portion of the meniscus by forming a notch portion having a surface that is substantially flush with the side surface inside the frame body of the standing wall portion. Is not formed, and it does not enter the upper surface of the flat plate portion. Therefore, it is possible to prevent cracks from occurring near the boundary due to the brazing material that has entered the upper surface of the flat plate portion.
[0025]
In the present invention, preferably, the length of the cut-out surface is 0.1 mm or more.
[0026]
With the above configuration, it is possible to effectively prevent the brazing material from being generated and to effectively prevent the brazing material from getting wet along the boundary portion between the flat plate portion and the standing wall portion.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
The optical semiconductor package of the present invention will be described below. FIG. 1 is a perspective view of an optical semiconductor package of the present invention. FIG. 2 is an enlarged perspective view of input / output terminals provided in the semiconductor package. In these drawings, 1 is a base, 2 is a frame, and 3 is an optical fiber. A cylindrical fixing member for fixing the metal holder 7 to which is attached, 4 is an input / output terminal, and 6 is a seal ring. The base body 1, the frame body 2, the fixing member 3, the input / output terminal 4, and the seal ring 6 accommodate therein a semiconductor element 9 as an optical semiconductor element such as an LD or PD, and a lid body on the upper surface of the seal ring 6. The container is configured by attachment.
[0028]
The base body 1 has a mounting portion 1a for mounting the semiconductor element 9 on its upper surface, functions as a support member for supporting the semiconductor element 9, and efficiently dissipates heat generated during operation of the semiconductor element 9 to the outside. It has a function.
[0029]
The substrate 1 has a substantially rectangular parallelepiped shape and is made of a metal material such as a copper (Cu) -tungsten (W) alloy or an Fe-Ni-Co alloy. Further, the production is formed into a predetermined shape by subjecting an alloy ingot to metal processing such as rolling or pressing.
[0030]
The substrate 1 has a metal having excellent corrosion resistance and excellent wettability with a brazing material on its surface, specifically, a Ni layer having a thickness of 0.5 to 9 μm and an Au layer having a thickness of 0.5 to 5 μm. If the layers are sequentially deposited by the plating method, it is possible to effectively prevent the base 1 from being oxidatively corroded and to firmly adhere and fix the semiconductor element 9 to the upper surface of the base 1. Therefore, it is preferable to deposit a metal layer such as a 0.5 to 9 μm Ni layer or a 0.5 to 5 μm thick Au layer on the surface of the substrate 1 by plating.
[0031]
Further, on the upper surface of the base body 1, a mounting portion 2 a composed of a through hole or a notch portion for fitting the input / output terminal 4 to the side portion so as to surround the mounting portion 1 a, and another side portion A frame body 2 formed with a through hole 2b functioning as an optical transmission path is joined with a brazing material such as silver brazing, and a space for accommodating the semiconductor element 9 is formed inside the frame body 2. Is done.
[0032]
The frame body 2 is made of the same metal material as that of the base body 1, and is manufactured by a processing method similar to that of the base body 1 so as to have a mounting portion 2 a on the side portion and a through hole 2 b on the other side portion. Processed.
[0033]
Note that the frame 2 is bonded to the base body 1 through a brazing material such as silver brazing, in which the upper surface of the base body 1 and the lower surface of the frame body 2 are laid on the upper surface of the base body 1 and have a suitable volume. Is done. Furthermore, a metal layer such as a Ni layer having a thickness of 0.5 to 9 μm or an Au layer having a thickness of 0.5 to 5 μm may be deposited on the surface of the frame body 2 by a plating method in the same manner as the substrate 1.
[0034]
The mounting portion 2a of the frame 2 has a function of inputting and outputting a high frequency signal between the semiconductor element 9 and an external electric circuit (not shown), and a function of blocking the inside and outside of the optical semiconductor package. The input / output terminal 4 having the same is joined by a brazing material such as silver brazing through a metallized layer provided on the input / output terminal 4.
[0035]
The input / output terminal 4 is formed by stacking a rectangular column-like standing wall portion 4b which is laid down in a substantially rectangular parallelepiped shape on the upper surface of a flat plate portion 4a having a substantially rectangular parallelepiped shape.
[0036]
The flat plate portion 4a is made of alumina (Al ₂ O ₃ ) Ceramics, aluminum nitride (AlN) ceramics, mullite (3Al ₂ O ₃ ・ 2SiO ₂ ) Made of dielectric material such as ceramics. On the upper surface of the flat plate portion 4a, a line conductor 4a-A made of a metallized layer such as W, Mo-Mn, or the like is formed from one long side to the other opposite side. A lower ground conductor 4a-C made of a metallized layer similar to the line conductor 4a-A is formed on the entire bottom surface of the flat plate portion 4a, and a side surface H (FIG. 5) parallel to the line conductor 4a-A is formed on the side surface. 2) A side formed of a metallized layer similar to the line conductor 4a-A in a part other than the notch part 4c provided by notching a part located inside the frame body 2 of the flat plate part 4a of the side face H. Partial ground conductor 4a-B is formed.
[0037]
When the input / output terminal 4 is fitted to the mounting portion 2a with a brazing material such as silver brazing, the notch 4c is formed in the frame 2 made of the side ground conductors 4a-B and the metal material. It can be effectively prevented from flowing in so as to fill a slight gap with the wall surface. Note that there are two gaps between the input / output terminal 4 and the frame 2 because there are two side faces H. That is, by providing the notch 4c, no brazing material pool is generated in a slight gap between the side ground conductor 4a-B and the inner wall surface of the frame 2. Therefore, the flat plate portion 4a having the lowest elasticity is caused by the difference in thermal expansion between the brazing material and the portion of the flat plate portion 4a located inside the frame body 2 and between the brazing material and the inner wall surface of the frame body 2. Does not cause thermal distortion or cracks.
[0038]
In addition, this notch 4c is the surface P (FIG. 5) notched in the frame 2 inside of the side surface joined to the frame 2 of the flat plate part 4a, and substantially flush with the side surface inside the frame 2 of the standing wall 4b. 2) The It is the notch part 4c which has, Preferably the length of the surface P is 0.1 mm or more. The cutout 4c only needs to be provided in at least one location on the flat plate portion 4a. When both locations are formed with a length of less than 0.1 mm, a slight gap is formed between the side ground conductor 4a-B and the inner wall surface of the frame 2. In addition, brazing material accumulation tends to occur at both locations. Therefore, the thermal strain generated by the difference in thermal expansion between the brazing material and the portion of the flat plate portion 4a located inside the frame 2 and between the brazing material and the inner wall surface of the frame 2 becomes large. As a result, a large compressive thermal stress is applied to the flat plate portion 4a, and cracks are easily generated.
[0039]
On the other hand, if the notch 4c of 0.1 mm or more is provided in one place and the notch 4c is not provided in the other place, even if the brazing material pool is generated in the part where the notch 4c is not provided, the other part There is no brazing material pool in the region. In this case, it was found that no cracks were generated in the flat plate portion 4a, and no cracks were generated in the flat plate portion 4a at the magnitude of the compressive thermal stress applied to the flat plate portion 4a.
[0040]
Therefore, the notch 4c has a surface P that is substantially flush with the side surface of the upright wall 4b inside the frame 2 at the portion located inside the frame 2 of the side surface H of the flat plate portion 4a. The length of the surface P is preferably 0.1 mm or more, and at least one such notch 4c is preferably provided.
[0041]
In addition, the inner peripheral surface of the notch 4c, that is, the surface formed by notching the side surface H of the flat plate portion 4a can have various shapes such as an R surface and a C surface. Further, as shown in FIG. 2, the cutout portion 4 c does not necessarily have to be formed by cutting out the entire surface inside the frame body 2 of the flat plate portion 4 a on the side surface H, and the shape in plan view including the surface P is semicircular. Alternatively, the cutout 4c may have an oval shape, a concave shape, or the like. In that case, the length of the notch 4c in the direction of the line conductor 4a-A only needs to be 1/3 or more of the entire length inside the frame 2 of the flat plate 4a on the side surface H, thereby forming a brazing material reservoir. Can be effectively prevented.
[0042]
In addition, when the semiconductor package is an optical semiconductor package, the notch 4c is formed on the side of the input / output terminal 4 that is close to the side of the frame 2 to which the fixing member 3 that fixes the optical fiber 8 and the like is joined. It is preferable to be provided. That is, when the notch portion 4c is not provided on the side portion close to the side portion to which the fixing member 3 is joined, the semiconductor element 9 is operated after adjusting the optical axis of the semiconductor element 9 and the optical fiber 8. When the heat generated by the semiconductor element 9 is transmitted to the frame body 2, a large thermal strain is generated in the frame body 2 together with the residual thermal stress between the brazing material and the inner wall surface of the frame body 2. Therefore, the optical axes of the optical fiber 8 and the semiconductor element 9 are shifted, and the operability of the semiconductor element 9 is impaired. Therefore, when the semiconductor package is an optical semiconductor package, the notch 4c is preferably provided on the side near the side of the frame 2 to which the fixing member 3 of the input / output terminal 4 is joined.
[0043]
In the case where an extra metallization layer is formed on the periphery of the laminated interface between the flat plate portion 4a and the standing wall portion 4b, that is, on the inner side of the side frame 2 or the outer side of the frame 2 joined to the frame 2 of the flat plate portion 4a. In some cases, the capacitance value between the line conductor 4a-A and the extra metallized layer becomes high, and transmission characteristics such as reflection due to impedance mismatch of the high frequency signal may be deteriorated. Therefore, in order to prevent an excessive metallization layer from being formed at all, the notch portions 4a are provided at four locations, two inside the frame body 2 and two outside the frame body 2 that are joined to the frame body 2 of the flat plate portion 4a. It is good to provide.
[0044]
Furthermore, when an extra metallization layer is formed inside the frame body 2 on the side surface joined to the frame body 2 of the flat plate portion 4a or outside the frame body 2, the flat plate portion 4a and the standing wall portion 4b on the upper surface of the flat plate portion 4a. In some cases, the brazing material forms a meniscus at the boundary portion and is easily wetted, and may enter the boundary portion. In this case, the brazing material that has entered the boundary portion generates stray capacitance between the line conductor 4a-A and degrades the transmission characteristics of the high-frequency signal. Therefore, in order to prevent such deterioration of the transmission characteristics, the notch portions 4a are provided at four locations, two locations inside the frame body 2 on the side surface and two locations outside the frame body 2 that are joined to the frame body 2 of the flat plate portion 4a. It is good to provide.
[0045]
The line conductor 4a-A, the side ground conductor 4a-B, and the lower ground conductor 4a-C of the flat plate portion 4a provided with the notch 4c are formed of a metallized layer such as W, Mo, or Mn. For example, a metal paste obtained by adding and mixing an organic solvent and a solvent to a powder such as W is preliminarily printed on a ceramic green sheet for the flat plate portion 4a in a predetermined pattern by a conventionally known screen printing method, followed by firing. It is formed by doing.
[0046]
Further, the standing wall portion 4b is laminated on the upper surface of the flat plate portion 4a. The standing wall portion 4b is made of the same dielectric as the flat plate portion 4a, and the upper ground conductor 4b-A made of the same metallized layer as the line conductor 4a-A is formed on the entire upper surface thereof, and the side surface H of the flat plate portion 4a. A side ground conductor 4b-B made of a metallized layer similar to the line conductor 104a-A is formed on the entire side surface that is substantially flush with the side ground conductor 4a-B.
[0047]
The upper ground conductor 4b-A and the side ground conductor 4b-B of the standing wall 4b are the same as the line conductor 4a-A, the side ground conductor 4a-B and the lower ground conductor 4a-C formed on the flat plate portion 4a. Is formed by printing and applying to a predetermined pattern and baking.
[0048]
As described above, the input / output terminal 4 includes the upper ground conductor 4b-A, the side ground conductor 4b-B, the side ground conductor 4a-B, and the lower ground conductor 4a-C, and the line conductor 4a-A is pseudo-coaxial. The structure allows high-frequency signal input / output to be favorable and is joined to a mounting portion 2a formed of a notch or a through-hole provided in the frame 2 via a brazing material such as silver brazing. It has a function of blocking the inside and outside of the semiconductor package. Furthermore, due to the notch portion 4c, the difference in thermal expansion between the brazing material and the portion of the flat plate portion 4a located inside the frame body 2 and between the brazing material and the inner wall surface of the frame body 2 causes the most. Thermal distortion and cracks are not generated in the flat plate portion 4a having low elasticity. Further, when the semiconductor package is an optical semiconductor package, the notch 4c is provided on the side of the input / output terminal 4 that is close to the side of the frame 2 to which the fixing member 3 that fixes the optical fiber 8 and the like is joined. As described above, it is preferable.
[0049]
In a portion of the input / output terminal 4 that is led out of the frame 2 of the line conductor 4a-A, input / output of a high-frequency signal between the external electric circuit and the input / output terminal 104 is performed, and an Fe-Ni-Co alloy or the like is used. Lead terminals 5 made of a metal material are joined with a brazing material such as silver brazing.
[0050]
In addition, a through hole 2b is formed in the other side portion of the frame 2 where the input / output terminal 4 is fitted to the side portion, and one end surface surrounds the opening of the through hole 2b. A fixing member 3 is provided on which the metal holder 7 bonded with a brazing material and the optical fiber 8 attached with an adhesive such as a resin is joined with a low melting point brazing material such as Au-Sn. The fixing member 3 is made by processing the same material as that of the base 1 and the frame 2 into a desired shape by the same processing method, and has a Ni layer of 0.5 to 9 μm and a surface of 0.5 to 5 μm on the surface thereof. A metal layer such as an Au layer may be deposited by a plating method.
[0051]
Thus, the seal ring 6 is joined to the upper surface of the frame 2 to which the input / output terminal 4 and the fixing member 3 are attached with a brazing material such as silver brazing. The seal ring 6 is joined to the upper surface of the frame body 2 by a brazing material such as silver brazing to sandwich the input / output terminal 4, and a lid body for sealing the semiconductor element 9 is formed on the upper surface by seam welding or the like. It functions as a medium for joining.
[0052]
An optical semiconductor package as a semiconductor package according to the present invention includes a base 1 made of a metal material and a metal material bonded to the upper surface of the base 1 so as to surround the mounting portion 1a of the semiconductor element 9 and having a mounting portion 2a and a through hole 2b. The frame body 2 is joined to the mounting portion 2a with a brazing material such as silver brazing, and between the brazing material and the portion located inside the frame body 2 of the flat plate portion 4a, and the brazing material and the inner wall surface of the frame body 2 And the input / output terminal 4 that can effectively prevent the occurrence of thermal distortion and cracks in the flat plate portion 4a due to the difference in thermal expansion between the two. The input / output terminal 4 has at least one cutout portion 4c formed by cutting out a side surface of a portion located inside the frame body 2 of the flat plate portion 4a.
[0053]
In such an optical semiconductor package, the semiconductor element 9 as an optical semiconductor element is placed and fixed on the placement portion 1a with a low melting point solder such as Sn-Pb solder, and the line conductor 4a-A and the semiconductor element 9 are fixed. The metal holder 7 is electrically connected with a bonding wire, and the optical fiber 8 is attached to the fixing member 3 with an adhesive such as a resin. The metal holder 7 is joined with a low melting point solder such as Au-Sn, and then the seal ring 6 By joining a lid to the upper surface by seam welding or the like, an optical semiconductor device as a product is obtained.
[0054]
In this optical semiconductor device, for example, the optical semiconductor element 9 is optically excited by a drive signal supplied from an external electric circuit, and the excited light such as laser light is transmitted to the optical fiber 8 and transmitted through the optical fiber 8. It functions as a photoelectric conversion device capable of transmitting a large amount of information at high speed, and is often used in the field of optical communications.
[0055]
Thus, since the present invention has a structure that effectively prevents cracks generated in the input / output terminals fitted in the semiconductor package, the semiconductor package must be enlarged or the input / output of high-frequency signals is impaired. Can solve the problem. As a result, the semiconductor element can be operated normally and stably over a long period of time.
[0056]
It should be noted that the present invention is not limited to the above-described embodiment, and various modifications are not hindered without departing from the gist of the present invention. For example, as shown in FIG. 3, the notch 4c is not only a portion located inside the frame body 2 on the side surface of the flat plate portion 4a but also a portion located outside the frame body 2 on the side surface of the flat plate portion 4a. In this case, the brazing material pool does not occur at a portion where the portion located outside the frame body 2 on the side surface of the flat plate portion 4a and the outer surface of the frame body 2 intersect. As a result, the thermal strain generated when the input / output terminal 4 is fitted to the mounting portion 2a of the frame body 2 can be made extremely small, and the joining can be made stronger.
[0057]
【The invention's effect】
The present invention relates to a semiconductor package having an input / output terminal composed of a flat plate portion made of a dielectric and an upright wall portion made of a dielectric, and the inside of the frame body of the upright wall portion at a portion inside the frame body on the side surface of the flat plate portion. A notch portion having a surface that is substantially flush with the side surface of the A metallized layer is formed on the side of the flat plate other than the notch Therefore, when this input / output terminal is provided on the semiconductor package via the brazing material, the brazing material and the portion located inside the frame on the side surface of the flat plate portion, and between the brazing material and the wall surface of the frame body Due to the difference in thermal expansion between them, thermal distortion and cracks are not generated in the flat plate portion having the lowest elasticity. As a result, it is possible to prevent the semiconductor package from becoming large and the input / output of high-frequency signals from being damaged, and the semiconductor element can be operated normally and stably over a long period of time.
[0058]
Conventionally, brazing material easily forms a meniscus at the boundary between the flat plate portion and the standing wall portion on the upper surface of the flat plate portion, so that it easily wets along the boundary portion. As a result, the brazing material enters the upper surface of the flat plate portion from the side surface of the flat plate portion. However, the brazing material does not form a meniscus at the boundary portion by forming a notch portion having a surface that is substantially flush with the side surface inside the frame body of the standing wall portion. No longer penetrates into the top surface. Therefore, it is possible to prevent cracks from occurring near the boundary due to the brazing material that has entered the upper surface of the flat plate portion.
[0059]
In addition, the present invention preferably prevents the formation of a brazing material pool effectively by the length of the surface notched substantially flush with the side surface of the standing wall portion inside the frame, Further, it is possible to effectively prevent the brazing material from getting wet along the boundary portion between the flat plate portion and the standing wall portion.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a semiconductor package of the present invention.
2 is an enlarged perspective view of an input / output terminal for the semiconductor package of FIG. 1;
FIG. 3 is an enlarged perspective view showing another embodiment of the input / output terminal of the present invention.
FIG. 4 is a perspective view of a conventional semiconductor package.
5 is an input / output terminal for the semiconductor package of FIG. 4;
[Explanation of symbols]
1: Substrate
1a: Placement part
2: Frame
2a: Mounting part
4: Input / output terminal
4a: Flat plate part
4b: Standing wall
4c: Notch
9: Semiconductor element

Claims

A base having a mounting portion on which a semiconductor element is mounted; a metal frame attached to the upper surface of the base so as to surround the mounting portion; and penetrating or cutting the frame. A flat plate portion made of a dielectric having a mounting portion of the input / output terminal formed lacking, a line conductor formed on the upper surface from one side to the opposite side, and the line conductor sandwiched between the upper surface of the flat plate portion In a package for housing a semiconductor element, having an upright wall portion made of a joined dielectric and an input / output terminal fitted and joined to the mounting portion, the side of the flat plate portion has a portion inside the frame body, A notch portion having a surface that is substantially flush with the side surface inside the frame body of the standing wall portion is formed, and a metallized layer is formed in a portion other than the notch portion on the side surface of the flat plate portion . Package for semiconductor element storage Di.

2. The package for housing a semiconductor element according to claim 1, wherein the length of the cut-out surface is 0.1 mm or more.