JP4041394B2

JP4041394B2 - Semiconductor element storage package and semiconductor device

Info

Publication number: JP4041394B2
Application number: JP2002375749A
Authority: JP
Inventors: 信幸田中
Original assignee: Kyocera Corp
Current assignee: Kyocera Corp
Priority date: 2002-12-26
Filing date: 2002-12-26
Publication date: 2008-01-30
Anticipated expiration: 2022-12-26
Also published as: JP2004207541A

Description

【０００１】
【発明の属する技術分野】
本発明は、半導体素子を収納するための半導体素子収納用パッケージおよび半導体装置に関し、特に、高周波信号の入出力を行なうリード端子を有する半導体素子収納用パッケージおよび半導体装置に関する。
【０００２】
【従来の技術】
従来、光通信分野等で使用されるマイクロ波帯やミリ波帯等の高周波信号を用い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、パッケージともいう）としては、例えば、半導体素子として半導体レーザ（ＬＤ）やフォトダイオード（ＰＤ）等の光半導体素子を用いた場合、図４に斜視図で示すようなものが用いられている。
【０００３】
このパッケージは、上面に形成された凹部の底面に半導体素子106を載置するための載置部101ａが設けられたセラミックスやプラスチックス等の絶縁体から成る直方体状の基体101と、この基体101の側壁部の外面に形成された複数の電極107と、凹部の底面から側壁部を貫通して複数の電極107にそれぞれ接続された線路導体108と、側壁部の外面に沿って下方に延びるように上端部が複数の電極107にそれぞれ接合されたリード端子105とを具備している。
【０００４】
また、リード端子105は高周波信号伝送用のリード端子105ａおよびその両側に接地用のリード端子105ｂを含んでいる。これにより、コプレーナ構造とすることによって、高周波信号を良好に伝送することができる。
【０００５】
側壁部には貫通孔101ｂが形成されている。この貫通孔101ｂに筒状の光ファイバ固定部材（以下、固定部材ともいう）102が嵌着される、または貫通孔101ｂの側壁部の外面側開口の周囲に固定部材102の一端が接合される。
【０００６】
側壁部の上面には、鉄（Ｆｅ）−ニッケル（Ｎｉ）−コバルト（Ｃｏ）合金等の金属から成るシールリング103が銀（Ａｇ）ロウ等のロウ材を介して接合され、蓋体104を強固に接合するための部材となる。
【０００７】
このようなパッケージの載置部101ａに半導体素子106を載置固定するとともに、半導体素子106の各電極と線路導体108とをボンディングワイヤを介して電気的に接続し、シールリング103の上面にＦｅ−Ｎｉ−Ｃｏ合金等から成る蓋体104をロウ付け法やシームウェルド法等の溶接法により接合することにより、半導体素子106を気密に封止する。そして、固定部材102に光ファイバを固定することによって、製品としての半導体装置となる。（例えば、下記の特許文献１参照）。
【０００８】
【特許文献１】
特開2001−127371号公報
【０００９】
【発明が解決しようとする課題】
しかしながら、特許文献１に示されるようなパッケージに１〜40ＧＨｚ程度の高周波帯域の高周波信号を入出力させると、高周波信号が線路導体108を通過する際に誘電体損失が生じ、それが大きな透過損失となるとともに、絶縁体から成る基体101の側壁部を介して、高周波信号伝送用の線路導体108と接地用の線路導体108との間に電気的な容量成分が発生して、高周波信号をパッケージの内外で効率よく伝送できないという問題点があった。
【００１０】
従って、本発明は上記従来の問題点に鑑み完成されたものであり、その目的は、１〜40ＧＨｚ程度の高周波帯域の高周波信号を低損失で入出力できる半導体素子収納用パッケージおよび半導体装置を提供することにある。
【００１１】
【課題を解決するための手段】
本発明の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半導体素子を載置するための載置部が設けられた絶縁体から成る直方体状の基体と、該基体の側壁部の外面に形成された複数の電極と、前記凹部の底面から前記側壁部を貫通して前記複数の電極にそれぞれ接続された線路導体と、前記側壁部の外面に沿って下方に延びるように上端部が前記複数の電極にそれぞれ接合されたリード端子とを具備した半導体素子収納用パッケージにおいて、前記複数の線路導体は高周波信号伝送用の線路導体を含んでおり、該高周波伝送用の線路導体に接続される前記電極は、上端部が下側よりも幅が狭い幅狭部とされ、前記高周波伝送用の線路導体は、前記電極の前記幅狭部と同じ幅とされており、前記基体は、前記側壁部の上面と外面との間で前記高周波信号伝送用の線路導体から上方の部位に段差部が形成されているとともに、前記高周波信号伝送用の線路導体が前記段差部の底面を通って前記電極の前記上端部に接続されていることを特徴とする。
【００１２】
本発明の半導体素子収納用パッケージは、複数の線路導体は高周波信号伝送用の線路導体を含んでおり、高周波伝送用の線路導体に接続される電極は、上端部が下側よりも幅が狭い幅狭部とされ、高周波伝送用の線路導体は、電極の幅狭部と同じ幅とされており、基体は、側壁部の上面と外面との間で高周波信号伝送用の線路導体から上方の部位に段差部が形成されているとともに、高周波信号伝送用の線路導体が段差部の底面を通って電極の上端部に接続されていることから、従来側壁部の内部に位置し比較的誘電率の高い側壁部で覆われていた高周波信号伝送用の線路導体の一部分の表面を側壁部よりも誘電率の小さな空気に露出させることによって、高周波信号伝送用の線路導体を伝送する高周波信号の誘電体損失を小さくすることができ、また、高周波信号伝送用の線路導体と接地用の線路導体との間に発生する浮遊容量等の容量成分を極めて小さくすることができる。その結果、１〜40ＧＨｚ程度の非常に高い周波数帯域の高周波信号を入出力させた場合においても、高周波信号の透過損失を低減させて、高周波信号の伝送効率の高いものとすることができる。
【００１３】
また、高周波信号伝送用の線路導体から上方の部位のみに段差部を有することから、段差部を有する側壁部の機械的強度が低下することなく維持され、半導体素子収納用パッケージの気密性が損なわれたり、半導体素子収納用パッケージに歪が生じたりすることもない。
【００１４】
本発明の半導体装置は、上記本発明の半導体素子収納用パッケージと、前記載置部に載置固定されるとともに前記線路導体に電気的に接続された半導体素子と、前記側壁部の上面に接合された蓋体とを具備したことを特徴とする。
【００１５】
本発明の半導体装置は、上記の構成により、半導体素子に非常に高い周波数帯域の高周波信号を低損失で入出力でき、その結果、高周波信号の伝送特性に優れたものとなる。
【００１６】
【発明の実施の形態】
本発明の半導体素子収納用パッケージについて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す斜視図である。同図において、１は上面に形成された凹部の底面に半導体素子６を載置する載置部１ａが設けられた絶縁体から成る直方体状の基体、７は基体１の側壁部の外面に形成された複数の電極、８は凹部の底面から基体１の側壁部を貫通して複数の電極７にそれぞれ接続された線路導体、５は側壁部の外面に沿って下方に延びるように上端部が複数の電極７にそれぞれ接合されたリード端子、Ａは段差部であり、主にこれらで内部に半導体素子６を収納するためのパッケージが構成される。
【００１７】
また、このパッケージの載置部１ａに半導体素子６を搭載固定し、半導体素子６と線路導体８とを電気的に接続し、基体１の側壁部の上面に蓋体４を接合することにより半導体装置となる。
【００１８】
本発明の基体１は、アルミナ（Ａｌ₂Ｏ₃）質焼結体，窒化アルミニウム（ＡｌＮ）質焼結体等のセラミックスやエポキシ樹脂，液晶ポリマー等の樹脂等から成る絶縁体から成り、その誘電率や熱膨張係数等の特性に応じて適宜選定される。
【００１９】
このような基体１は、例えばＡｌ₂Ｏ₃セラミックスから成る場合、以下のようにして作製される。まず、Ａｌ₂Ｏ₃，酸化珪素（ＳｉＯ₂），酸化カルシウム（ＣａＯ），酸化マグネシウム（ＭｇＯ）等の原料粉末に適当な有機バインダや可塑剤，分散剤，溶剤等を添加混合して泥漿状となす。これを従来周知のドクターブレード法でシート状に成形することによって複数枚のセラミックグリーンシートを得る。しかる後、これらのセラミックグリーンシートに適当な打ち抜き加工を施し凹部１ａや段差部Ａとなる貫通孔や切欠きを形成するとともに、線路導体８や電極７となる金属ペーストを印刷塗布して積層する。最後に、この積層体の側壁部の上面に必要に応じてシールリング３を接合させるためのメタライズ金属層となる金属ペーストを印刷塗布し、還元雰囲気中で約1600℃の温度で焼成することによって製作される。
【００２０】
基体１の側壁部の外面に形成された複数の電極７は、高周波信号伝送用の電極７ａと接地用の電極７ｂとを含む。接地用の電極７ｂは、１〜40ＧＨｚ程度の高周波信号を高周波信号伝送用の電極７ａに低損失で入出力させるために、電極７ａの両側に設けられて接地電位を強化している。これにより、１〜40ＧＨｚ程度の高周波信号が伝送された際にその伝送特性が良好になる。
【００２１】
好ましくは、図１に示すように高周波信号伝送用の電極７ａの上端は、接地用電極７ｂの上端と略同一の高さとされているのがよい。これにより、電極７ａの接地がより強化され、高周波信号の伝送特性がより向上する。
【００２２】
さらに、高周波信号伝送用の電極７ａは、その上端部の幅がそれより下側の幅よりも狭くされ、高周波信号伝送用の線路導体８ａと同じ幅でもって接続される。これにより、高周波信号伝送用の電極７ａの幅狭部とされた上端部は、接地用の電極７ｂとの間の間隔が広がるため、電極７ａ，７ｂ間で発生する容量成分を小さくすることができる。その結果、高周波信号の伝送効率がより向上し、高周波信号の伝送損失をより少なくすることができる。
【００２３】
なお、電極７ａと電極７ｂとの間隔は、0.03〜２ｍｍがよい。これにより、電極７ａを伝送する高周波信号の損失を小さくして伝送効率を向上させることができる。0.03ｍｍ未満では、電極７ａと電極７ｂとが短絡し易くなる。また、２ｍｍを超えると、電極７ｂの接地電位による高周波信号の損失を抑制する効果が小さくなる。
【００２４】
線路導体８は凹部の底面から基体１の側壁部を貫通して複数の電極７にそれぞれ接続されている。線路導体８は、高周波信号伝送用の線路導体８ａと接地用の線路導体８ｂとを含み、それぞれ高周波信号伝送用の電極７ａおよび接地用の電極７ｂに接続されている。
【００２５】
高周波信号伝送用の線路導体８ａは、基体１の側壁部において、接地用の線路導体８ｂと同一面で平行に設けられるのがよい。これにより基体１の側壁部において高周波信号伝送用の線路導体８ａをコプレーナ線路とすることができ、高周波信号の損失を抑制でき、１〜40ＧＨｚ程度の高周波信号の伝送特性をより良好なものとすることができる。
【００２６】
このような線路導体８および電極７は、タングステン（Ｗ），モリブデン（Ｍｏ），マンガン（Ｍｎ）等の高融点金属粉末に適当な有機バインダ、溶剤等を添加混合して得た導体ペーストを、基体１となるセラミックグリーンシートの積層体に、従来周知のスクリーン印刷法により所定パターンで印刷塗布した後焼成することによって基体１に被着される。または、基体１となるセラミックグリーンシートの積層体を焼成した後に、導体ペーストを所定パターンに印刷塗布し焼成することによって基体１に被着される。
【００２７】
なお、線路導体８は、図１に示すように、基体１の凹部に形成された基体１の一部から成る棚部の上面に設けられていてもよい。これにより載置部１ａに搭載される半導体素子６の電極の高さと線路導体８の高さとを近づけることができ、半導体素子６の電極と線路導体８とを電気的に接続するボンディングワイヤの長さが短くなって高周波信号の伝送特性が向上する。
【００２８】
基体１は、側壁部の上面と外面との間で高周波信号伝送用の線路導体８ａから上方の部位に段差部Ａが形成されているとともに、高周波信号伝送用の線路導体８ａが段差部Ａの底面を通って側壁部の外面の電極７に接続されている。これにより、従来側壁部の内部に位置し比較的誘電率の高い側壁部で覆われていた高周波信号伝送用の線路導体８ａの一部分の表面を側壁部よりも誘電率の小さな空気に露出させることによって、高周波信号伝送用の線路導体８ａを伝送する高周波信号の誘電体損失を小さくすることができ、また、高周波信号伝送用の線路導体８ａと接地用の線路導体８ｂとの間に発生する浮遊容量等の容量成分を極めて小さくすることができる。その結果、１〜40ＧＨｚ程度の非常に高い周波数帯域の高周波信号を入出力させた場合においても、高周波信号の透過損失を低減させて、高周波信号の伝送効率の高いものとすることができる。
【００２９】
また、高周波信号伝送用の線路導体８ａから上方の部位のみに段差部Ａを有することから、段差部Ａを有する側壁部の機械的強度が低下することなく維持され、パッケージの気密性が損なわれたり、パッケージに歪が生じたりすることもない。
【００３０】
段差部Ａは、基体１となるセラミックグリーンシートに打ち抜き加工等で段差部Ａと成る切欠きを形成した後、複数の他のセラミックグリーンシートと積層し、焼成することによって作製される。
【００３１】
段差部Ａは、図１，図２，図３（ａ）に示すように基体１の側壁部の外面側にあってもよく、図３（ｂ）に示すように内面側にあってもよい。また、図３（ｃ）に示すように外面側と内面側の両方にあってもよい。また、段差部Ａの平面視形状は、図３（ａ）〜（ｃ）に示すような四角形であってもよく、図３（ｄ）に示すような半円形や、図３（ｅ）に示すようなＵ字形であってもよく、種々の形状とし得る。好ましくは、図３（ｄ），（ｅ）に示すように段差部Ａの角部が曲面状であるのがよく、蓋体４と基体１との熱膨張差による応力が段差部Ａの角部に集中するのを抑制し、段差部Ａにクラック等の破損が発生するのを有効に抑制できる。
【００３２】
段差部Ａの長さ（奥行き）ａ（図２）は、0.5〜５ｍｍであるのがよい。これにより、高周波信号伝送用の線路導体８ａの空気に露出している部位の割合が大きくなり、線路導体８ａを伝送する高周波信号の透過損失を低減して高周波信号の伝送効率を向上させることができる。
【００３３】
ａ＜0.5ｍｍである場合、線路導体８ａの空気に露出している部位の割合が小さくなり、線路導体８ａを伝送する高周波信号の透過損失を低減する効果が小さくなる。また、ａ＞５ｍｍである場合、基体１の段差部Ａにおける側壁部の厚みが小さくなり、基体１の側壁部の強度が低下してクラック等の破損が発生し易くなる。
【００３４】
段差部Ａの高さｂ（図２）は、0.5〜10ｍｍであるのがよい。これにより、基体１の側壁部内の線路導体８ａを伝送する高周波信号に発生する透過損失を低減できるとともに、段差部Ａによる基体１の側壁部の強度の低下を少なくし、基体１の側壁部にクラック等の破損が発生するのを抑制できる。
【００３５】
ｂ＜0.5ｍｍの場合、線路導体８ａと蓋体４との間に発生する容量成分が大きくなり、高周波信号伝送用の線路導体８ａを伝送する高周波信号に大きな透過損失が生じ易い。一方、ｂ＞５ｍｍの場合、段差部Ａによって基体１の側壁部が薄くなる部位の割合が大きくなり、基体１の側壁部の強度が低下してクラック等の破損が発生し易くなる。
【００３６】
段差部Ａの幅ｃ（図２）は、線路導体８ａの幅をｄとすると、1.5ｄ≦ｃ≦20ｄ（0.5〜10ｍｍ程度）であるのがよい。これにより、線路導体８ａを伝送する高周波信号の透過損失を低減できるとともに、段差部Ａによって基体１の側壁部の強度の低下を少なくして、基体１の側壁部にクラック等の破損が発生するのを防止できる。
【００３７】
ｃ＜1.5ｄの場合、セラミックグリーンシートを積層して基体１を形成する際のセラミックグリーンシートの積層ずれによって、線路導体８ａが段差部Ａからずれ易くなり、線路導体８ａを伝送する高周波信号に誘電体損失が発生し易くなるとともに、線路導体８ａと線路導体８ｂとの間に大きな容量成分が発生して、透過損失が増大し易くなる。また、ｃ＞20ｄの場合、段差部Ａによって基体１の側壁部が薄くなる部位の割合が大きく、基体１の側壁部にクラック等の破損が発生し易くなる。
【００３８】
リード端子５は、基体１の側壁部の外面に沿って下方に延びるように上端部が複数の電極７にそれぞれ接合されている。リード端子５は、高周波信号伝送用のリード端子５ａおよび接地用のリード端子５ｂを含み、それぞれ高周波信号伝送用の電極７ａおよび接地用の電極７ｂと接合されている。
【００３９】
このようなリード端子５は、基体１との熱膨張係数差による熱歪みを有効に抑制するとともに高周波信号を伝送させるために、基体１の熱膨張係数に近似した金属から成るのがよい。その金属としては、Ｆｅ−Ｎｉ合金やＦｅ−Ｎｉ−Ｃｏ合金等がよく、例えばＦｅ−Ｎｉ−Ｃｏ合金のインゴット（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。
【００４０】
また、基体１の上面には、基体１と蓋体４との熱膨張係数差による熱歪みを有効に抑制するとともに基体１の側壁部の上面に蓋体４をシーム溶接等の溶接等により強固に接合するために金属製のシールリング３が、Ａｇロウ等のロウ材を介して接合されているのがよい。その金属としてはＦｅ−Ｎｉ合金やＦｅ−Ｎｉ−Ｃｏ合金等がよく、例えばＦｅ−Ｎｉ−Ｃｏ合金のインゴット（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。
【００４１】
シールリング３は、基体１の側壁部の上面にＷ，Ｍｏ，Ｍｎ等の高融点金属粉末に適当な有機バインダ、溶剤等を添加混合して得た導体ペーストを塗布し、焼成することによって得られたメタライズ金属層にＡｇロウ等のロウ材を介して接合される。
【００４２】
基体１の側壁部の上面にシールリング３が接合されている場合、段差部Ａとシールリング３との間の距離ｅ（図２）は0.3〜３ｍｍであるのがよい。これにより、基体１内の線路導体８ａを伝送する高周波信号の透過損失を低減できるとともにシールリング３と基体１の側壁部との熱膨張差による応力によって段差部Ａにクラック等の破損が発生するのを有効に抑制できる。
【００４３】
ｅ＜0.3ｍｍの場合、段差部Ａとシールリング３との間の距離が非常に短くなり、シールリング３と基体１の側壁部との熱膨張差による応力が段差部Ａに加わり易くなって、段差部Ａにクラック等の破損が生じ易くなる。また、線路導体８ａとシールリング３との間で、基体１の絶縁体を介して発生する容量成分が大きくなり、また、シールリング３を基体１の側壁部に接合するためのロウ材が段差部Ａの内部に流れ込み易くなり、段差部Ａの底面の線路導体８ａとシールリング３とが電気的に短絡して線路導体８ａを高周波信号が伝送し難くなる。
【００４４】
一方、ｅ＞３ｍｍの場合、線路導体８ａの基体１の側壁部を貫通する部位が長くなり、高周波信号の伝送効率を向上させる効果が小さくなる。
【００４５】
また、載置部１ａに載置される半導体素子６がＬＤ，ＰＤ等の光半導体素子である場合、光ファイバをパッケージ内部に導入して半導体素子６と光ファイバ（図示せず）とを光結合させるため、図１に示すように基体１の側壁部に形成された貫通孔１ｂに嵌着されるかまたは貫通孔１ｂの側壁部の外面側の開口の周囲に一端が接合された筒状の固定部材２を有している。
【００４６】
固定部材２は軸方向に貫通孔が形成されている。この固定部材２の貫通孔のパッケージの外側の一端に光ファイバが金属ホルダ（図示せず）を介して接合固定され、固定部材２の貫通孔の他端の内周面に光を集光するためのガラス，サファイア等から成るレンズ等の透光性部材（図示せず）が接合される。これにより、光ファイバと半導体素子６とが透光性部材を介して効率よく光信号の授受を行なうことができる。
【００４７】
このような固定部材２は、半導体素子６の熱により基体１が加熱されて基体１の側壁部との熱膨張係数差によって生じる歪を有効に抑制するために、基体１の熱膨張係数に近似した金属等が用いられる。その金属としては、Ｆｅ−Ｎｉ合金やＦｅ−Ｎｉ−Ｃｏ合金等がよく、例えばＦｅ−Ｎｉ−Ｃｏ合金のインゴット（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。
【００４８】
本発明の半導体装置は、上記本発明のパッケージと、載置部１ａに載置固定されるとともに線路導体８に電気的に接続された半導体素子６と、基体１の側壁部の上面に接合された蓋体４とを具備している。これにより、半導体素子６に非常に高い周波数帯域の高周波信号を低損失で入出力でき、その結果、高周波信号の伝送特性に優れたものとなる。
【００４９】
このような半導体装置は、パッケージの載置部１ａに半導体素子６をガラス，樹脂，ロウ材等の接着剤を介して接着固定し、半導体素子６の各電極をボンディングワイヤを介して凹部の底面に設けられた線路導体８に電気的に接続し、しかる後、基体１の側壁部の上面にＦｅ−Ｎｉ合金やＦｅ−Ｎｉ−Ｃｏ合金等の金属やセラミックス、樹脂等から成る蓋体４をシーム溶接等の溶接やロウ付け等により接合して半導体素子６を内部に気密に封止することにより作製される。
【００５０】
かくして、本発明の半導体装置は、リード端子５が外部電気回路基板の外部電気回路に電気的に接続されることにより、外部電気回路から供給される電気信号によって半導体素子６が駆動され、大容量の情報を高速に処理することが可能となる。
【００５１】
【実施例】
本発明の半導体素子収納用パッケージの実施例を以下に説明する。
【００５２】
図１のパッケージを以下のように構成した。先ず、焼成後の比誘電率が9.5となるＡｌ₂Ｏ₃セラミックグリーンシートに打ち抜き加工を施し、Ｗペーストを印刷塗布することにより線路導体８、電極７、シールリング３接合用のメタライズ金属層を形成した。そして、これらを積層し、還元雰囲気中で約1600℃の温度で焼成することにより、上面に縦4.5ｍｍ×横6.8ｍｍ×深さ３ｍｍの凹部を有する縦7.5ｍｍ×横13ｍｍ×高さ4.5ｍｍの直方体の基体１のサンプルＰを作製した。なお、サンプルＰは、基体１の側壁部に形成された段差部Ａの大きさが長さ（奥行き）ａ0.5ｍｍ×高さｂ１ｍｍ×幅ｃ1.2ｍｍ、段差部Ａの底面に形成された高周波信号伝送用の線路導体８ａの幅が0.6ｍｍであり、線路導体８ａの両側にはそれぞれ1.45ｍｍの間隔をおいて1.3ｍｍの幅の接地用の線路導体８ｂが形成されたものを用いた。
【００５３】
また、比較例として図４の構成のサンプルＱをサンプルＰと同様に作製した。なお、このサンプルＱは、段差部Ａを設けないこと以外はサンプルＰと同様であり、線路導体８ａ，８ｂおよび電極７をすべてサンプルＰと同様の位置に同様の幅で形成した。
【００５４】
これらのサンプルＰ，Ｑについて、線路導体８ａと線路導体８ｂとの間に発生する容量成分を測定した。この結果、サンプルＰで0.058ｐＦ、サンプルＱで0.3ｐＦとなって、サンプルＰではサンプルＱに比べ容量成分が飛躍的に低減されていることがわかった。
【００５５】
さらに、線路導体８ａに１〜40ＧＨｚの高周波信号を入力してその透過損失を測定した結果を図５に示す。図５より、サンプルＰはサンプルＱに比べて１〜40ＧＨｚの全周波数帯域で透過損失が改善され、１〜40ＧＨｚ帯域の高周波信号を入出力する場合に透過損失を有効に低減できることがわかった。
【００５６】
なお、本発明は上記実施の形態および実施例に限定されず、本発明の要旨を逸脱しない範囲内で種々の変更を施すことは何等差し支えない。
【００５７】
【発明の効果】
本発明の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半導体素子を載置するための載置部が設けられた絶縁体から成る直方体状の基体と、基体の側壁部の表面に形成された複数の電極と、凹部の底面から側壁部を貫通して複数の電極にそれぞれ接続された線路導体と、側壁部の外面に沿って下方に延びるように上端部が複数の電極にそれぞれ接合されたリード端子とを具備した半導体素子収納用パッケージにおいて、複数の線路導体は高周波信号伝送用の線路導体を含んでおり、高周波伝送用の線路導体に接続される電極は、上端部が下側よりも幅が狭い幅狭部とされ、高周波伝送用の線路導体は、電極の幅狭部と同じ幅とされており、基体は、側壁部の上面と外面との間で前記高周波信号伝送用の線路導体から上方の部位に段差部が形成されているとともに、高周波信号伝送用の線路導体が段差部の底面を通って電極の上端部に接続されていることから、従来側壁部の内部に位置し比較的誘電率の高い側壁部で覆われていた高周波信号伝送用の線路導体の一部分の上面を側壁部よりも誘電率の小さな空気に露出させることによって、高周波信号伝送用の線路導体を伝送する高周波信号の誘電体損失を小さくすることができ、また、高周波信号伝送用の線路導体と接地用の線路導体との間に発生する浮遊容量等の容量成分を極めて小さくすることができる。その結果、１〜40ＧＨｚ程度の非常に高い周波数帯域の高周波信号を入出力させた場合においても、高周波信号の透過損失を低減させて、高周波信号の伝送効率の高いものとすることができる。
【００５８】
また、高周波信号伝送用の線路導体から上方の部位のみに段差部を有することから、段差部を有する側壁部の機械的強度が低下することなく維持され、半導体素子収納用パッケージの気密性が損なわれたり、半導体素子収納用パッケージに歪が生じたりすることもない。
【００５９】
本発明の半導体装置は、上記本発明の半導体素子収納用パッケージと、載置部に載置固定されるとともに線路導体に電気的に接続された半導体素子と、側壁部の上面に接合された蓋体とを具備したことにより、半導体素子に非常に高い周波数帯域の高周波信号を低損失で入出力でき、その結果、高周波信号の伝送特性に優れたものとなる。
【図面の簡単な説明】
【図１】本発明の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斜視図である。
【図２】図１の半導体素子収納用パッケージの要部拡大斜視図である。
【図３】（ａ）〜（ｅ）は本発明の半導体素子収納用パッケージにおける段差部について実施の形態の各種例を示す上面図である。
【図４】従来の半導体素子収納用パッケージの斜視図である。
【図５】本発明の半導体素子収納用パッケージと従来の半導体素子収納用パッケージについて高周波信号の透過損失を測定した結果のグラフである。
【符号の説明】
１：基体
１ａ：載置部
４：蓋体
５：リード端子
６：半導体素子
７：電極
８：線路導体
８ａ：高周波信号伝送用の線路導体
８ｂ：接地用の線路導体
Ａ：段差部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a semiconductor element housing package and a semiconductor device for housing a semiconductor element, and more particularly to a semiconductor element housing package and a semiconductor device having lead terminals for inputting and outputting a high frequency signal.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a semiconductor element storage package (hereinafter also referred to as a package) for storing various semiconductor elements using high-frequency signals such as microwave bands and millimeter wave bands used in the field of optical communication, for example, semiconductors as semiconductor elements When an optical semiconductor element such as a laser (LD) or a photodiode (PD) is used, the one shown in a perspective view in FIG. 4 is used.
[0003]
This package includes a rectangular parallelepiped base 101 made of an insulator such as ceramics or plastics provided with a mounting portion 101a for mounting a semiconductor element 106 on the bottom surface of a recess formed on the upper surface, and the base 101 A plurality of electrodes 107 formed on the outer surface of the side wall, a line conductor 108 penetrating the side wall from the bottom surface of the recess and connected to the plurality of electrodes 107, and extending downward along the outer surface of the side wall And a lead terminal 105 whose upper ends are respectively joined to the plurality of electrodes 107.
[0004]
The lead terminal 105 includes a lead terminal 105a for high-frequency signal transmission and ground lead terminals 105b on both sides thereof. Thereby, a high frequency signal can be satisfactorily transmitted by using the coplanar structure.
[0005]
A through hole 101b is formed in the side wall portion. A cylindrical optical fiber fixing member (hereinafter also referred to as a fixing member) 102 is fitted into the through hole 101b, or one end of the fixing member 102 is joined around the outer surface side opening of the side wall portion of the through hole 101b. .
[0006]
A seal ring 103 made of a metal such as an iron (Fe) -nickel (Ni) -cobalt (Co) alloy is joined to the upper surface of the side wall portion via a brazing material such as silver (Ag) brazing, and the lid 104 is attached. It becomes a member for joining firmly.
[0007]
The semiconductor element 106 is mounted and fixed on the mounting portion 101a of such a package, and each electrode of the semiconductor element 106 and the line conductor 108 are electrically connected through bonding wires, and Fe on the upper surface of the seal ring 103. The semiconductor element 106 is hermetically sealed by bonding the lid 104 made of a Ni—Co alloy or the like by a welding method such as a brazing method or a seam weld method. Then, the optical fiber is fixed to the fixing member 102. And Therefore, it becomes a semiconductor device as a product. (For example, refer to Patent Document 1 below).
[0008]
[Patent Document 1]
JP 2001-127371 A
[0009]
[Problems to be solved by the invention]
However, when a high frequency signal in a high frequency band of about 1 to 40 GHz is input / output to a package as disclosed in Patent Document 1, a dielectric loss occurs when the high frequency signal passes through the line conductor 108, which causes a large transmission loss. In addition, an electrical capacitance component is generated between the line conductor 108 for high-frequency signal transmission and the line conductor 108 for grounding through the side wall portion of the base 101 made of an insulator, and the high-frequency signal is packaged. There was a problem that it was not possible to transmit efficiently inside and outside.
[0010]
Accordingly, the present invention has been completed in view of the above-described conventional problems, and an object of the present invention is to provide a package for housing a semiconductor element and a semiconductor device capable of inputting and outputting a high-frequency signal in a high-frequency band of about 1 to 40 GHz with low loss. There is to do.
[0011]
[Means for Solving the Problems]
The package for housing a semiconductor element of the present invention includes a rectangular parallelepiped base made of an insulator provided with a placement portion for placing a semiconductor element on the bottom surface of a recess formed on the upper surface, and a side wall portion of the base body. A plurality of electrodes formed on the outer surface, line conductors that pass through the side wall portion from the bottom surface of the recess and are connected to the plurality of electrodes, and an upper end portion that extends downward along the outer surface of the side wall portion Wherein the plurality of line conductors include line conductors for high-frequency signal transmission, and are connected to the line conductors for high-frequency transmission. The electrode, the upper end portion is a narrow portion narrower than the lower side, the high-frequency transmission line conductor is the electrode of the electrode Same as narrow part The base is formed with a step portion at an upper portion from the line conductor for high-frequency signal transmission between the upper surface and the outer surface of the side wall, and the high-frequency signal transmission line A conductor is connected to the upper end portion of the electrode through the bottom surface of the stepped portion.
[0012]
In the package for housing a semiconductor element of the present invention, the plurality of line conductors include line conductors for high-frequency signal transmission, and the electrodes connected to the line conductors for high-frequency transmission have an upper end narrower than the lower side. The line conductor for high-frequency transmission is a narrow part. Same as narrow part The base is formed with a stepped portion at an upper portion from the line conductor for high-frequency signal transmission between the upper surface and the outer surface of the side wall portion, and the line conductor for high-frequency signal transmission is a stepped portion. Since it is connected to the upper end of the electrode through the bottom surface of the electrode, the surface of a part of the line conductor for high-frequency signal transmission that is conventionally located inside the side wall and covered with the side wall having a relatively high dielectric constant is covered. By exposing to air having a dielectric constant smaller than that of the side wall, the dielectric loss of the high-frequency signal transmitted through the line conductor for high-frequency signal transmission can be reduced, and the line conductor for high-frequency signal transmission and grounding Capacitance components such as stray capacitance generated between the two line conductors can be made extremely small. As a result, even when a high frequency signal in a very high frequency band of about 1 to 40 GHz is input / output, the transmission loss of the high frequency signal can be reduced and the transmission efficiency of the high frequency signal can be increased.
[0013]
In addition, since the step portion is provided only in the portion above the line conductor for high-frequency signal transmission, the mechanical strength of the side wall portion having the step portion is maintained without lowering, and the airtightness of the package for housing the semiconductor element is impaired. And no distortion occurs in the semiconductor element storage package.
[0014]
The semiconductor device of the present invention is bonded to the semiconductor element storage package of the present invention, a semiconductor element mounted and fixed on the mounting portion and electrically connected to the line conductor, and an upper surface of the side wall portion. And a covered lid.
[0015]
With the above-described configuration, the semiconductor device of the present invention can input and output a high frequency signal in a very high frequency band to the semiconductor element with low loss, and as a result, has excellent transmission characteristics of the high frequency signal.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
The semiconductor element storage package of the present invention will be described in detail below. FIG. 1 is a perspective view showing an example of an embodiment of a package of the present invention. In the figure, reference numeral 1 denotes a rectangular parallelepiped base made of an insulator provided with a mounting portion 1 a for mounting a semiconductor element 6 on the bottom surface of a recess formed on the upper surface, and 7 is formed on the outer surface of the side wall portion of the base 1. The plurality of electrodes 8 are line conductors that are respectively connected to the plurality of electrodes 7 through the side wall portion of the base 1 from the bottom surface of the recess, and 5 has an upper end portion extending downward along the outer surface of the side wall portion. Lead terminals A respectively joined to the plurality of electrodes 7 are stepped portions, and these mainly constitute a package for housing the semiconductor element 6 therein.
[0017]
Further, the semiconductor element 6 is mounted and fixed on the mounting portion 1a of the package, the semiconductor element 6 and the line conductor 8 are electrically connected, and the lid body 4 is joined to the upper surface of the side wall portion of the base body 1 to thereby form the semiconductor. It becomes a device.
[0018]
The substrate 1 of the present invention is made of alumina (Al ₂ O _Three ) Made of insulators made of ceramics such as sintered ceramics, aluminum nitride (AlN) sintered bodies, resins such as epoxy resins, liquid crystal polymers, etc., and selected as appropriate according to the characteristics such as dielectric constant and thermal expansion coefficient Is done.
[0019]
Such a substrate 1 is, for example, Al ₂ O _Three When made of ceramics, it is manufactured as follows. First, Al ₂ O _Three , Silicon oxide (SiO ₂ ), Calcium oxide (CaO), magnesium oxide (MgO) and other raw material powders are mixed with a suitable organic binder, plasticizer, dispersant, solvent, etc. to form a slurry. A plurality of ceramic green sheets are obtained by forming this into a sheet by a conventionally known doctor blade method. Thereafter, these ceramic green sheets are appropriately punched to form through holes and notches that become the recesses 1a and stepped portions A, and are printed and coated with a metal paste that becomes the line conductors 8 and the electrodes 7. . Finally, a metal paste to be a metallized metal layer for joining the seal ring 3 is printed on the upper surface of the side wall portion of the laminate as necessary, and fired at a temperature of about 1600 ° C. in a reducing atmosphere. Produced.
[0020]
The plurality of electrodes 7 formed on the outer surface of the side wall portion of the base 1 include a high-frequency signal transmission electrode 7a and a grounding electrode 7b. The grounding electrode 7b is provided on both sides of the electrode 7a in order to input and output a high-frequency signal of about 1 to 40 GHz to the high-frequency signal transmission electrode 7a with low loss, thereby strengthening the ground potential. As a result, a high frequency signal of about 1 to 40 GHz is transmitted. This The transmission characteristics are improved.
[0021]
Preferably, as shown in FIG. 1, the upper end of the high-frequency signal transmission electrode 7a should be substantially the same height as the upper end of the ground electrode 7b. Thereby, the grounding of the electrode 7a is further strengthened, and the transmission characteristic of the high frequency signal is further improved.
[0022]
Further, the high-frequency signal transmission electrode 7a has a width at its upper end that is narrower than its lower width. High It is connected with the same width as the line conductor 8a for frequency signal transmission. The As a result, the gap between the upper end portion, which is the narrow portion of the electrode 7a for high-frequency signal transmission, and the ground electrode 7b is widened, so that the capacitance component generated between the electrodes 7a and 7b can be reduced. it can. As a result, the transmission efficiency of the high frequency signal can be further improved, and the transmission loss of the high frequency signal can be further reduced.
[0023]
The distance between the electrode 7a and the electrode 7b is preferably 0.03 to 2 mm. Thereby, the loss of the high frequency signal which transmits the electrode 7a can be made small, and transmission efficiency can be improved. If it is less than 0.03 mm, the electrodes 7a and 7b are easily short-circuited. If it exceeds 2 mm, the effect of suppressing the loss of the high-frequency signal due to the ground potential of the electrode 7b becomes small.
[0024]
The line conductor 8 penetrates the side wall of the base 1 from the bottom surface of the recess and is connected to the plurality of electrodes 7 respectively. The line conductor 8 includes a line conductor 8a for high frequency signal transmission and a line conductor 8b for grounding, and is connected to the electrode 7a for high frequency signal transmission and the electrode 7b for grounding, respectively.
[0025]
The line conductor 8a for high-frequency signal transmission is preferably provided on the side wall portion of the base 1 in parallel with the ground line conductor 8b. As a result, the line conductor 8a for high frequency signal transmission can be a coplanar line at the side wall portion of the substrate 1, the loss of the high frequency signal can be suppressed, and the transmission characteristic of the high frequency signal of about 1 to 40 GHz can be improved. be able to.
[0026]
Such a line conductor 8 and electrode 7 are made of a conductive paste obtained by adding and mixing an appropriate organic binder, solvent, etc. to a high melting point metal powder such as tungsten (W), molybdenum (Mo), manganese (Mn), etc. The laminate of ceramic green sheets to be the base 1 is applied to the base 1 by printing and applying in a predetermined pattern by a conventionally known screen printing method and then firing. Alternatively, after the ceramic green sheet laminate to be the substrate 1 is fired, the conductor paste is printed and applied in a predetermined pattern and fired to adhere to the substrate 1.
[0027]
As shown in FIG. 1, the line conductor 8 may be provided on the upper surface of the shelf portion formed of a part of the base body 1 formed in the concave portion of the base body 1. Thereby, the height of the electrode of the semiconductor element 6 mounted on the mounting portion 1a can be made close to the height of the line conductor 8, and the length of the bonding wire for electrically connecting the electrode of the semiconductor element 6 and the line conductor 8 can be made. The transmission characteristics of high frequency signals are improved.
[0028]
The base 1 has a stepped portion A formed between the upper surface and the outer surface of the side wall portion at a position above the line conductor 8a for high-frequency signal transmission, and the line conductor 8a for high-frequency signal transmission of the stepped portion A. It is connected to the electrode 7 on the outer surface of the side wall through the bottom surface. As a result, the surface of a part of the line conductor 8a for high-frequency signal transmission, which is conventionally located inside the side wall and covered with the side wall having a relatively high dielectric constant, is exposed to air having a lower dielectric constant than that of the side wall. Thus, the dielectric loss of the high-frequency signal transmitted through the high-frequency signal transmission line conductor 8a can be reduced, and floating generated between the high-frequency signal transmission line conductor 8a and the grounding line conductor 8b can be reduced. Capacitance components such as capacity can be made extremely small. As a result, even when a high frequency signal in a very high frequency band of about 1 to 40 GHz is input / output, the transmission loss of the high frequency signal can be reduced and the transmission efficiency of the high frequency signal can be increased.
[0029]
Further, since the stepped portion A is provided only at a portion above the line conductor 8a for high frequency signal transmission, the mechanical strength of the side wall portion having the stepped portion A is maintained without being lowered, and the airtightness of the package is impaired. Nor distortion of the package.
[0030]
The stepped portion A is produced by forming a notch to be the stepped portion A by punching or the like in the ceramic green sheet to be the base 1, and then laminating and firing the other ceramic green sheets.
[0031]
The stepped portion A may be on the outer surface side of the side wall portion of the base 1 as shown in FIGS. 1, 2, and 3A, or may be on the inner surface side as shown in FIG. 3B. . Moreover, as shown in FIG.3 (c), you may exist in both an outer surface side and an inner surface side. Further, the planar view shape of the stepped portion A may be a quadrangle as shown in FIGS. 3A to 3C, a semicircular shape as shown in FIG. It may be U-shaped as shown, and may have various shapes. Preferably, as shown in FIGS. 3 (d) and 3 (e), the corners of the stepped portion A should be curved, and the stress due to the difference in thermal expansion between the lid 4 and the substrate 1 is the corner of the stepped portion A. It is possible to suppress the concentration on the portion and to effectively prevent the stepped portion A from being damaged such as a crack.
[0032]
The length (depth) a (FIG. 2) of the stepped portion A is preferably 0.5 to 5 mm. As a result, the proportion of the portion of the line conductor 8a for high-frequency signal transmission that is exposed to the air increases, and the transmission loss of the high-frequency signal transmitted through the line conductor 8a is reduced to improve the transmission efficiency of the high-frequency signal. it can.
[0033]
When a <0.5 mm, the proportion of the part of the line conductor 8a exposed to the air is reduced, and the effect of reducing the transmission loss of the high-frequency signal transmitted through the line conductor 8a is reduced. Further, when a> 5 mm, the thickness of the side wall portion in the stepped portion A of the base body 1 is reduced, the strength of the side wall portion of the base body 1 is lowered, and breakage such as cracks is likely to occur.
[0034]
The height b (FIG. 2) of the stepped portion A is preferably 0.5 to 10 mm. As a result, transmission loss generated in the high-frequency signal transmitted through the line conductor 8a in the side wall portion of the base body 1 can be reduced, and a decrease in strength of the side wall portion of the base body 1 due to the stepped portion A can be reduced. The occurrence of breakage such as cracks can be suppressed.
[0035]
When b <0.5 mm, the capacitance component generated between the line conductor 8a and the lid 4 becomes large, and a large transmission loss tends to occur in the high-frequency signal transmitted through the line conductor 8a for high-frequency signal transmission. On the other hand, in the case of b> 5 mm, the ratio of the portion where the side wall portion of the base body 1 becomes thin due to the stepped portion A is increased, the strength of the side wall portion of the base body 1 is lowered, and breakage such as cracks is likely to occur.
[0036]
The width c (FIG. 2) of the stepped portion A is preferably 1.5d ≦ c ≦ 20d (about 0.5 to 10 mm), where d is the width of the line conductor 8a. As a result, transmission loss of the high-frequency signal transmitted through the line conductor 8a can be reduced, and a decrease in strength of the side wall portion of the base body 1 is reduced by the stepped portion A, and damage such as cracks occurs in the side wall portion of the base body 1. Can be prevented.
[0037]
In the case of c <1.5d, the line conductor 8a is easily displaced from the stepped portion A due to the stacking deviation of the ceramic green sheet when the base 1 is formed by stacking the ceramic green sheets, and the high frequency signal transmitted through the line conductor 8a is changed. Dielectric loss is likely to occur, and a large capacitance component is generated between the line conductor 8a and the line conductor 8b, so that transmission loss is likely to increase. Further, in the case of c> 20d, the ratio of the portion where the side wall portion of the base body 1 becomes thin due to the stepped portion A is large, and the side wall portion of the base body 1 is likely to be damaged such as a crack.
[0038]
Lead terminals 5 are joined at their upper ends to a plurality of electrodes 7 so as to extend downward along the outer surface of the side wall of base 1. The lead terminal 5 includes a lead terminal 5a for high-frequency signal transmission and a lead terminal 5b for grounding, and is joined to an electrode 7a for high-frequency signal transmission and a grounding electrode 7b, respectively.
[0039]
Such a lead terminal 5 is preferably made of a metal that approximates the thermal expansion coefficient of the base body 1 in order to effectively suppress thermal distortion due to the difference in thermal expansion coefficient with the base body 1 and to transmit a high-frequency signal. As the metal, an Fe—Ni alloy, an Fe—Ni—Co alloy, or the like is preferable. For example, a conventionally known metal processing method such as a rolling method or a punching method is applied to an ingot of the Fe—Ni—Co alloy. By this, it is formed in a predetermined shape.
[0040]
In addition, the upper surface of the base body 1 is effectively suppressed from thermal distortion due to the difference in thermal expansion coefficient between the base body 1 and the lid body 4, and the lid body 4 is firmly attached to the upper surface of the side wall portion of the base body 1 by welding such as seam welding. The metal seal ring 3 is preferably bonded via a brazing material such as Ag brazing. As the metal, Fe-Ni alloy, Fe-Ni-Co alloy, etc. are good. For example, a well-known metal processing method such as a rolling method or a punching method is applied to an ingot of the Fe-Ni-Co alloy. To form a predetermined shape.
[0041]
The seal ring 3 is obtained by applying a conductive paste obtained by adding and mixing an appropriate organic binder, solvent, etc. to a refractory metal powder such as W, Mo, Mn, etc. on the upper surface of the side wall portion of the substrate 1 and firing it. The resulting metallized metal layer is bonded via a brazing material such as Ag brazing.
[0042]
When the seal ring 3 is bonded to the upper surface of the side wall portion of the substrate 1, the distance e (FIG. 2) between the stepped portion A and the seal ring 3 is preferably 0.3 to 3 mm. As a result, transmission loss of a high-frequency signal transmitted through the line conductor 8a in the base 1 can be reduced, and damage such as a crack occurs in the stepped portion A due to a stress due to a difference in thermal expansion between the seal ring 3 and the side wall of the base 1. Can be effectively suppressed.
[0043]
When e <0.3 mm, the distance between the stepped portion A and the seal ring 3 becomes very short, and stress due to the difference in thermal expansion between the seal ring 3 and the side wall portion of the base 1 is easily applied to the stepped portion A. The stepped portion A is likely to be damaged such as a crack. Further, the capacitance component generated through the insulator of the base body 1 is increased between the line conductor 8a and the seal ring 3, and the brazing material for joining the seal ring 3 to the side wall portion of the base body 1 has a step. The line conductor 8a on the bottom surface of the stepped portion A and the seal ring 3 are electrically short-circuited, and it is difficult to transmit a high-frequency signal through the line conductor 8a.
[0044]
On the other hand, in the case of e> 3 mm, the part which penetrates the side wall part of the base | substrate 1 of the line conductor 8a becomes long, and the effect which improves the transmission efficiency of a high frequency signal becomes small.
[0045]
Further, when the semiconductor element 6 placed on the placement portion 1a is an optical semiconductor element such as an LD or PD, an optical fiber is introduced into the package, and the semiconductor element 6 and the optical fiber (not shown) are optically coupled. As shown in FIG. 1, a cylindrical shape is fitted into a through hole 1b formed in the side wall portion of the base 1 or joined at one end around an opening on the outer surface side of the side wall portion of the through hole 1b. The fixing member 2 is provided.
[0046]
The fixing member 2 has a through hole formed in the axial direction. An optical fiber is bonded and fixed to one end outside the package of the through hole of the fixing member 2 via a metal holder (not shown), and the light is condensed on the inner peripheral surface of the other end of the through hole of the fixing member 2. A translucent member (not shown) such as a lens made of glass, sapphire or the like is bonded. As a result, the optical fiber and the semiconductor element 6 can efficiently exchange optical signals through the translucent member.
[0047]
Such a fixing member 2 approximates the thermal expansion coefficient of the base 1 in order to effectively suppress the distortion caused by the difference in thermal expansion coefficient from the side wall of the base 1 when the base 1 is heated by the heat of the semiconductor element 6. The metal etc. which were made are used. As the metal, an Fe—Ni alloy, an Fe—Ni—Co alloy, or the like is preferable. For example, a conventionally known metal processing method such as a rolling method or a punching method is applied to an ingot of the Fe—Ni—Co alloy. By this, it is formed in a predetermined shape.
[0048]
The semiconductor device of the present invention is bonded to the package of the present invention, the semiconductor element 6 mounted and fixed on the mounting portion 1 a and electrically connected to the line conductor 8, and the upper surface of the side wall portion of the base 1. And a lid 4. Thereby, a high frequency signal in a very high frequency band can be inputted / outputted to / from the semiconductor element 6 with low loss, and as a result, the high frequency signal transmission characteristics are excellent.
[0049]
In such a semiconductor device, the semiconductor element 6 is bonded and fixed to the mounting portion 1a of the package via an adhesive such as glass, resin, or brazing material, and each electrode of the semiconductor element 6 is attached to the bottom surface of the recess via a bonding wire. Then, the lid 4 made of a metal such as Fe—Ni alloy or Fe—Ni—Co alloy, ceramics, resin, or the like is formed on the upper surface of the side wall portion of the base 1. It is manufactured by sealing the semiconductor element 6 inside by welding such as seam welding or brazing.
[0050]
Thus, in the semiconductor device of the present invention, when the lead terminal 5 is electrically connected to the external electric circuit of the external electric circuit board, the semiconductor element 6 is driven by the electric signal supplied from the external electric circuit, and the large capacity Can be processed at high speed.
[0051]
【Example】
Embodiments of the semiconductor element storage package of the present invention will be described below.
[0052]
The package of FIG. 1 was configured as follows. First, Al whose dielectric constant after firing is 9.5 ₂ O _Three The ceramic green sheet was punched and a metallized metal layer for joining the line conductor 8, the electrode 7 and the seal ring 3 was formed by printing and applying a W paste. These are laminated and fired in a reducing atmosphere at a temperature of about 1600 ° C., so that the upper surface has a recess of 4.5 mm length × 6.8 mm width × 3 mm depth, length 7.5 mm × width 13 mm × height 4.5 mm. A sample P of the rectangular parallelepiped substrate 1 was prepared. In the sample P, the size of the stepped portion A formed on the side wall portion of the base 1 is length (depth) a0.5 mm × height b1 mm × width c1.2 mm, and the high frequency formed on the bottom surface of the stepped portion A. The signal transmission line conductor 8a has a width of 0.6 mm, and a grounding line conductor 8b having a width of 1.3 mm is formed on both sides of the line conductor 8a at intervals of 1.45 mm.
[0053]
As a comparative example, a sample Q having the configuration shown in FIG. The sample Q is the same as the sample P except that the stepped portion A is not provided, and the line conductors 8a and 8b and the electrode 7 are all formed at the same position as the sample P with the same width.
[0054]
For these samples P and Q, the capacitance component generated between the line conductor 8a and the line conductor 8b was measured. As a result, it was found that the sample P was 0.058 pF and the sample Q was 0.3 pF, and the capacity component of the sample P was dramatically reduced compared to the sample Q.
[0055]
Further, FIG. 5 shows a result of measuring a transmission loss by inputting a high frequency signal of 1 to 40 GHz to the line conductor 8a. From FIG. 5, it was found that the transmission loss of sample P is improved in all frequency bands of 1 to 40 GHz as compared with sample Q, and the transmission loss can be effectively reduced when high-frequency signals of 1 to 40 GHz band are input and output.
[0056]
It should be noted that the present invention is not limited to the above-described embodiments and examples, and various modifications may be made without departing from the scope of the present invention.
[0057]
【The invention's effect】
The package for housing a semiconductor element of the present invention includes a rectangular parallelepiped base made of an insulator provided with a mounting portion for mounting a semiconductor element on the bottom surface of a recess formed on the upper surface, and the surface of the side wall portion of the base A plurality of electrodes formed on the bottom surface, line conductors penetrating the side walls from the bottom of the recesses and connected to the plurality of electrodes, respectively, and upper ends of the plurality of electrodes extending downward along the outer surface of the side walls. In the package for housing semiconductor elements each having a lead terminal bonded thereto, the plurality of line conductors include line conductors for high-frequency signal transmission, and an electrode connected to the line conductor for high-frequency transmission has an upper end portion. The width is narrower than the lower side, and the line conductor for high-frequency transmission is Same as narrow part The base is formed with a step portion at an upper portion from the line conductor for high-frequency signal transmission between the upper surface and the outer surface of the side wall portion, and the line conductor for high-frequency signal transmission is stepped. Since it is connected to the upper end portion of the electrode through the bottom surface of the portion, the upper surface of a part of the line conductor for high-frequency signal transmission that is conventionally located inside the side wall portion and covered with the side wall portion having a relatively high dielectric constant Is exposed to air having a dielectric constant smaller than that of the side wall, so that the dielectric loss of the high-frequency signal transmitted through the line conductor for high-frequency signal transmission can be reduced. Capacitance components such as stray capacitance generated between the line conductors can be made extremely small. As a result, even when a high frequency signal in a very high frequency band of about 1 to 40 GHz is input / output, the transmission loss of the high frequency signal can be reduced and the transmission efficiency of the high frequency signal can be increased.
[0058]
In addition, since the step portion is provided only in the portion above the line conductor for high-frequency signal transmission, the mechanical strength of the side wall portion having the step portion is maintained without lowering, and the airtightness of the package for housing the semiconductor element is impaired. And no distortion occurs in the semiconductor element storage package.
[0059]
A semiconductor device according to the present invention includes a semiconductor element storage package according to the present invention, a semiconductor element mounted and fixed on the mounting portion and electrically connected to the line conductor, and a lid bonded to the upper surface of the side wall portion. The high-frequency signal in a very high frequency band can be input to and output from the semiconductor element with low loss, and as a result, the transmission characteristics of the high-frequency signal are excellent.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of an embodiment of a package for housing a semiconductor element of the present invention.
2 is an enlarged perspective view of a main part of the package for housing a semiconductor element of FIG. 1;
FIGS. 3A to 3E are top views showing various examples of the embodiment of the step portion in the package for housing a semiconductor element of the present invention. FIGS.
FIG. 4 is a perspective view of a conventional semiconductor element housing package.
FIG. 5 is a graph showing a result of measuring a transmission loss of a high-frequency signal for a package for housing a semiconductor element of the present invention and a conventional package for housing a semiconductor element.
[Explanation of symbols]
1: Substrate
1a: Placement part
4: Lid
5: Lead terminal
6: Semiconductor element
7: Electrode
8: Line conductor
8a: Line conductor for high-frequency signal transmission
8b: Line conductor for grounding
A: Stepped part

Claims

A rectangular parallelepiped base made of an insulator provided with a mounting portion for mounting a semiconductor element on the bottom surface of the recess formed on the upper surface, and a plurality of electrodes formed on the outer surface of the side wall portion of the base; Line conductors that pass through the side wall from the bottom surface of the recess and are connected to the plurality of electrodes, respectively, and upper ends joined to the plurality of electrodes so as to extend downward along the outer surface of the side wall. In the package for housing a semiconductor element having a lead terminal, the plurality of line conductors include a line conductor for high-frequency signal transmission, and the electrode connected to the line conductor for high-frequency transmission has an upper end on the bottom. The high-frequency transmission line conductor has the same width as the narrow portion of the electrode, and the base is between the upper surface and the outer surface of the side wall portion. The line guide for high frequency signal transmission A semiconductor element housing, wherein a step portion is formed in a portion above the step, and the line conductor for high-frequency signal transmission is connected to the upper end portion of the electrode through the bottom surface of the step portion. For package.

A package for housing a semiconductor element according to claim 1, a semiconductor element mounted on and fixed to the mounting part and electrically connected to the line conductor, and a lid joined to the upper surface of the side wall part. A semiconductor device comprising the semiconductor device.