【０００１】
【発明の属する技術分野】
本発明は、フォトダイオード，ラインセンサ，イメージセンサ等の受光素子である光半導体素子またはこれらの受光部を有する光半導体素子を具備した光半導体装置に関する。
【０００２】
【従来の技術】
従来のフォトダイオード（ＰＤ），ラインセンサ，イメージセンサ等の受光素子である光半導体素子またはこれらの受光部を有する光半導体素子を具備した光半導体装置を図３に示す。図３において、１０１は、基体１０２、光半導体素子１０３および透光性蓋体１０８から主に構成される光半導体装置である。１０２ａは基体１０２の上側主面に形成された凹部、１０２ｂは凹部１０２ａの底面、１０２ｃは基体１０２の側壁部、１０３は基体１０２に実装される光半導体素子、１０３ａは光半導体素子１０３の上面の中央部に設けられた受光部、１０４は光半導体素子１０３の上面の外周部に設けられた電極である。また、１０５は基体１０２の凹部１０２ａの底面１０２ｂの外周部に設けられた電極パッド、１０６はボンディングワイヤ、１０７は基体１０２の上面の凹部１０２ａの周囲の略全周に設けられた樹脂層、１０８はガラス等からなる透光性蓋体である。
【０００３】
この光半導体装置１０１を構成する基体１０２はセラミックス等からなり、基体１０２の底板部の上面の外周部に、別体の枠状の側壁部１０２ｃが設けられている。基体１０２の底板部と側壁部１０２ｃとは一体的に形成されていてもよい。また、基体１０２の凹部１０２ａの底面１０２ｂの外周部には電極パッド１０５が設けられている。
【０００４】
光半導体素子１０３は基体１０２の底面１０２ｂに載置され接着されており、光半導体素子１０３の上面の外周部には電極１０４が設けられている。電極１０４と電極パッド１０５とは、Ａｕ，Ａｌ等からなるボンディングワイヤ１０６により電気的に接続される。また、透光性蓋体１０８が樹脂層１０７を介して基体１０２の側壁部１０２ｃの上面に接着される（例えば、下記の特許文献１参照）。
【０００５】
【特許文献１】
特開平５−３２３２３０号公報
【０００６】
【発明が解決しようとする課題】
しかしながら、上記従来の光半導体装置１０１においては、光半導体素子１０３を載置する底板としての基体１０２の厚み、光半導体素子１０３を囲むように設けられた側壁部１０２ｃの厚み、光半導体素子１０３を載置接着するための接着層の厚み、および側壁部１０２ｃ上面の外形と略同形状のガラス等からなる透光性蓋体１０８を側壁部１０２ｃ上面に載置し接着封止するための樹脂層１０７の厚み等の公差ばらつきがあった。そのため、光半導体素子１０３の上面と透光性蓋体１０８の下面とを平行にすることが困難であるという問題があった。
【０００７】
このような問題があることから、例えば光半導体装置１０１をカメラ等に組み込んだ場合、レンズを備えた鏡筒と光半導体装置１０１との位置合わせに透光性蓋体１０８の表面が使用されるため、光半導体素子１０３上面の受光部１０３ａに対して鏡筒のレンズが傾き、画像の取り込みに不具合が生じるといった問題点が発生していた。
【０００８】
この問題点を解決するために、特許文献１には、図４に示すような、透光性蓋体２０４が光半導体素子２０３に対して平行になるように位置決めを行う基準面として、基体２０２の側壁部の内側面に設けられた、透光性蓋体２０４の両端部の底面を支持する一対の第１の基準面２０２ａと、透光性蓋体２０４の中央部底面を支持する第２の基準面２０２ｂとを有することにより、透光性蓋体２０４の反りを容易に矯正できる画像装置２０１が提案されている。
【０００９】
しかしながら、上記従来例のいずれにおいても、光半導体素子を載置する底板としての基体の厚み公差や反り、また基体の上側主面の外周部に光半導体素子を囲むように設けられた側壁部の厚み公差、光半導体素子を載置接着するための接着層の厚みのばらつきによる影響を避けることができず、その結果、光半導体素子上面の受光部に対する鏡筒レンズの傾きが発生するという問題点は解決されていなかった。
【００１０】
従って、本発明は上記問題点に鑑みて完成されたものであり、その目的は、光半導体装置内に収納された光半導体素子の上面の受光部と透光性蓋体の下面とを平行にすることにより、光半導体装置の受光特性を良好なものとすることにある。
【００１１】
【課題を解決するための手段】
本発明の光半導体装置は、上面に光半導体素子を収容する凹部が形成されるとともに、該凹部の内周にその上面に前記光半導体素子の電極が電気的に接続される配線導体が配設された段差部が形成された基体と、前記凹部の底面に載置され、上面の中央部に受光部が設けられているとともに外周部に電極が形成された光半導体素子と、前記基体の上面の前記凹部の周囲の略全周に設けられた樹脂層と、該樹脂層の上部で接着されて前記光半導体素子を封止する透光性蓋体とを具備した光半導体装置であって、前記段差部の上面から前記透光性蓋体の下面にかけて略同じ高さを有する支持部材を略等間隔で３個以上設けたことを特徴とするものである。
【００１２】
本発明の光半導体装置は、前記段差部の上面から前記透光性蓋体の下面にかけて略同じ高さを有する支持部材を略等間隔で３個以上設けたことから、基体の側壁部の厚み公差、光半導体素子を基体の凹部の底面に接着するための接着層の厚みのばらつきに殆ど影響されずに、光半導体素子の上面の受光部に対して透光性蓋体の下面を平行にすることができる。その結果、光半導体装置をカメラ等に組み込んだ場合、レンズを備えた鏡筒と光半導体装置との位置合わせに透光性蓋体の表面を使用すれば、光半導体素子の受光部に対し、鏡筒レンズを平行に取り付けることができる。従って、画像取り込みの際に良好な結像が得られ、鮮明で高画質の画像が得られる。
【００１３】
【発明の実施の形態】
本発明の光半導体装置について以下に詳細に説明する。図１は本発明の光半導体装置について実施の形態の一例を示す断面図、図２は図１の光半導体装置の平面図である。これらの図において、１は、基体２、枠体２ｃ、光半導体素子３、透光性蓋体８および支持部材９から主に構成される光半導体装置である。２ａは基体２の上面に形成された凹部、２ｂは凹部２ａの底面、２ｃは基体２の側壁部、３は基体２に実装される光半導体素子、３ａは光半導体素子３の上面の中央部に設けられた受光部、４は光半導体素子３の上面の外周部に設けられた入出力用の電極である。また、５は基体２の凹部２ａの内周の段差部２ｄの上面に設けられた配線導体の一部である電極パッド、６はＡｕ，Ａｌ等から成るボンディングワイヤ、７は基体２の上面の凹部２ａの周囲の略全周に設けられた樹脂層、８はガラス、石英、サファイヤ、透明樹脂等からなる透光性蓋体である。
【００１４】
本発明の光半導体装置１は、上面に凹部２ａが形成されるとともに、凹部２ａの内周にその上面に光半導体素子３の電極４が電気的に接続される電極パッド５が配設された段差部２ｄが形成された基体２と、凹部２ａの底面２ｂに載置され、上面の中央部に受光部３ａが設けられているとともに外周部に電極４が形成された光半導体素子３と、上面の凹部２ａの周囲の略全周に設けられた樹脂層７と、樹脂層７の上部で接着されて光半導体素子３を封止する透光性蓋体８とを具備し、段差部２ｄの上面から透光性蓋体８の下面にかけて略同じ高さを有する支持部材９を略等間隔で３個以上設けた構成である。
【００１５】
この光半導体装置１を構成する基体２はセラミックス等からなり、基体２の底板部の上面の外周部に、別体の枠状の側壁部２ｃが設けられている。また、基体２の底板部と側壁部２ｃとは一体化されていてもよい。
【００１６】
光半導体素子３は基体２の底面２ｂに載置され接着固定されており、光半導体素子３の上面の外周部には電極４が設けられている。電極４と電極パッド５とは、Ａｕ，Ａｌ等からなるボンディングワイヤ６により電気的に接続される。また、透光性蓋体８が樹脂層７を介して基体２の側壁部２ｃの上面に接着固定される。
【００１７】
本発明の支持部材９は、アルミナ（Ａｌ２Ｏ３）質焼結体，窒化アルミニウム（ＡｌＮ）質焼結体，炭化珪素（ＳｉＣ）質焼結体，窒化珪素（Ｓｉ３Ｎ４）質焼結体，ガラスセラミックス等のセラミックス、Ｆｅ−Ｎｉ−Ｃｏ合金，Ａｌ，Ｃｕ等の金属、またはアクリル系樹脂，エポキシ系樹脂，シリコーン樹脂，ポリエーテルアミド系樹脂等の樹脂から成る。支持部材９は基体２の凹部２ａの内周の段差部２ｄから透光性蓋体８との間に設置されるため、光半導体装置１全体が外部回路基板等に実装される際の熱で支持部材９が膨張し、基体２や透光性蓋体８にストレスを与える可能性が有る。このことから、上記材料の中でも熱膨張係数の低いセラミックスが好適である。例えば熱膨張係数が５×１０−６〜１０×１０−６／℃程度のアルミナを主成分としたセラミックスを用いるのが好ましい。
【００１８】
支持部材９の形状としては、高さは３００〜１５００μｍがよく、また断面形状は、一辺の長さが１００μｍ〜１ｍｍの多角形である多角柱状、直径１００μｍ〜１ｍｍの円形である円柱状、または長径が１００μｍ〜１ｍｍの楕円径である楕円柱状等がよい。
【００１９】
高さが３００μｍ未満では、支持部材９がボンディングワイヤ６の最上部および側壁部２ｃの最上面よりも低くなる場合がある。高さが１５００μｍを超えると、光半導体装置１自体の厚みが増し大型になるので好ましくない。
【００２０】
支持部材９の断面形状については、支持部材９は基体２の底面２ｂで光半導体素子１と側壁部２ｃとの間の狭い領域に設置する必要があるため、多角柱状の場合断面の一辺の長さが１ｍｍ以下であり、円柱状の場合断面の直径が１ｍｍ以下であり、楕円柱状の場合断面の長径が１ｍｍ以下であることが好ましい。一方、多角柱状の場合断面の一辺の長さが１００μｍ未満であり、円柱状の場合断面の直径が１００μｍ未満であり、楕円柱状の場合断面の長径が１００μｍ未満であると、支持部材９が細すぎるため、その加工性、設置する際の作業性が悪くなる。
【００２１】
従って、支持部材９のより好ましい形状としては、高さが６００〜１１００μｍ、断面形状は、多角柱状の場合一辺の長さが２００〜５００μｍの多角形、円柱状の場合直径が２００〜５００μｍの円形、楕円柱状の場合長径が２００〜５００μｍの楕円形であることがよい。
【００２２】
支持部材９の設置場所としては、光半導体素子３の平面視形状が略四角形の場合、光半導体素子３の周囲でそのコーナー部付近の凹部２ａの内周の段差部２ｄがよく、光半導体素子３の１個あたり略等間隔で３〜４個設置することが好ましい。これは、光半導体素子３の受光部３ａに対し透光性蓋体８が平行になるように支持するためには、光半導体素子３の周囲に極力間隔を開けて設置するのがよいからであり、また３個以上なくては平行に支持するのが困難である。支持部材９の設置間隔は、受光部３ａの中心に関して等角度間隔とすることができる。３個の場合１２０°間隔、図２に示すように４個の支持部材９ａ〜９ｄを設ける場合９０°間隔とすればよい。
【００２３】
支持部材９の上端面は、側壁部２ｃの上面より高い位置にあるのがよい。側壁部２ｃの上面には樹脂層７があるため、支持部材９の上端面は樹脂層７の下端よりも高い位置にあるのがよく、その場合支持部材９を透光性蓋体８の下面に接着するのが容易になる。また、支持部材９の上端面は、樹脂層７の下端よりは高く、樹脂層７の上端以下の低い位置にあるのが好ましい。支持部材９の上端面が樹脂層７の上端より高くなると、透光性蓋体８の下面が樹脂層７から剥離し易くなる。
【００２４】
また、支持部材９の形状として、下側が上側よりも太く、上端が尖った形状であってもよい。この場合、支持部材９が軟質のものであれば、透光性蓋体８の下面に支持部材９の上端が当接した状態で透光性蓋体８の傾斜を微調整する際に少なくとも一部の支持部材９の上端が潰れることにより、透光性蓋体８を光半導体素子３の受光部３ａに平行な状態として固定することができる。また、支持部材９が硬質のものであれば、透光性蓋体８の下面に支持部材９の上端が当接した状態で透光性蓋体８の傾斜を微調整する際に少なくとも一部の支持部材９の上端が透光性蓋体８の下面に突き刺さることにより、透光性蓋体８を光半導体素子３の受光部３ａに平行な状態として固定することができる。
【００２５】
また、支持部材９を設置する際は、アクリル系樹脂，エポキシ系樹脂，シリコーン系樹脂，ポリエーテルアミド系樹脂等から成る接着剤を用いて固定する。支持部材９の上端面および／または下端面を接着すれば良い。
【００２６】
本発明の基体２は、アルミナ（Ａｌ２Ｏ３）質焼結体，窒化アルミニウム（ＡｌＮ）質焼結体，炭化珪素（ＳｉＣ）質焼結体，窒化珪素（Ｓｉ３Ｎ４）質焼結体，ガラスセラミックス等のセラミックス、またはＦｅ−Ｎｉ−Ｃｏ合金，Ｆｅ−Ｎｉ合金，Ａｌ，Ｃｕ等の金属から成る。また、側壁部２ｃは基体２と別体であってもよいが、その場合基体２と同じ材料から成るのがよい。
【００２７】
基体２の凹部２ａの内周の段差部２ｄに電極パッド５が設けられているが、この電極パッド５は、基体２の側壁部２ｃ外面および基体２の下面等に形成されたメタライズ層等から成る配線パターンやリード端子等（図示せず）を介して外部電気回路等に接続される。
【００２８】
本発明の光半導体素子３は、ＰＤ，ラインセンサ，イメージセンサ，ＣＣＤ（Ｃｈａｒｇｅ Ｃｏｕｐｌｅｄ Ｄｅｖｉｃｅ），ＥＰＲＯＭ（Ｅｒａｓａｂｌｅ ａｎｄ Ｐｒｏｇｒａｍｍａｂｌｅ ＲＯＭ）等の受光素子、またはこれらの受光部を有する光半導体素子である。この光半導体素子３を基体２の底面２ｂに接着する際、銀ペースト等から成る接合材を用いて固定するが、接合材の厚みをできるだけ薄くした方がよい。具体的には接合材の厚みは５０μｍ以下がよい。この場合、底面２ｂに対する光半導体素子３の平行度が良くなり、支持部材９を設置することによる、光半導体素子３に対する透光性蓋体８の平行度の向上効果が大きくなる。
【００２９】
樹脂層７は、アクリル系樹脂，エポキシ系樹脂，シリコーン系樹脂，ポリエーテルアミド系樹脂等から成る。この樹脂層７は、余計な外光の入射を遮断するために、黒色、茶色、暗緑色、濃青色等の暗色系の染料や顔料を混入させてもよい。
【００３０】
【実施例】
本発明の光半導体装置の実施例を以下に説明する。
【００３１】
図１，図２の光半導体装置１を以下のようにして構成した。アルミナセラミックスから成る基体２、ＣＣＤから成る光半導体素子３、ガラスから成る透光性蓋体８を用い、光半導体素子３を基体２の底面２ｂに厚さ３０μｍの銀ペースト（銀を含有する樹脂接着剤）で接着し、段差部２ｄの底面の電極パッド５と光半導体素子３の上面の電極４とをＡｕ製のボンディングワイヤ６で接続した。次に、段差部２ｄの底面の四隅部に、直径５００μｍ、高さ１ｍｍでアルミナセラミックスから成る円柱状の支持部材９ａ〜９ｄをエポキシ系樹脂で接着するとともに、透光性蓋体８をエポキシ系樹脂から成る樹脂層７で接着した。
【００３２】
また、比較例として、支持部材９ａ〜９ｄがない以外は上記実施例と同様にして図３に示した光半導体装置１０１を作製した。
【００３３】
そして、本発明の光半導体装置１と比較例のものとを比較検討した。支持部材９ａ〜９ｄを有していない比較例の半導体装置１０１では、光半導体素子１０３の受光部１０３ａと透光性蓋体１０８との平行度、即ち受光部１０３ａと透光性蓋体１０８との間の隙間の最大値と最小置の差は約１００μｍであったが、本発明の光半導体装置１では３０μｍ以下にまで抑えることができた。なお、測定の方法としては、金属顕微鏡等の高倍率（１００〜４００倍）の顕微鏡を用い、焦点深度によって光半導体素子の上面と透光性蓋体の下面との間の距離を測る方法を用いた。
【００３４】
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あれば種々の変更は可能である。
【００３５】
【発明の効果】
本発明の光半導体装置は、上面に光半導体素子を収容する凹部が形成されるとともに、凹部の内周にその上面に光半導体素子の電極が電気的に接続される配線導体が配設された段差部が形成された基体と、凹部の底面に載置され、上面の中央部に受光部が設けられているとともに外周部に電極が形成された光半導体素子と、基体の上面の凹部の周囲の略全周に設けられた樹脂層と、樹脂層の上部で接着されて光半導体素子を封止する透光性蓋体とを具備し、段差部の上面から透光性蓋体の下面にかけて略同じ高さを有する支持部材を略等間隔で３個以上設けたことにより、基体の側壁部の厚み公差、光半導体素子を基体の凹部の底面に接着するための接着層の厚みのばらつきに殆ど影響されずに、光半導体素子の上面の受光部に対して透光性蓋体の下面を平行にすることができる。その結果、光半導体装置をカメラ等に組み込んだ場合、レンズを備えた鏡筒と光半導体装置との位置合わせに透光性蓋体の表面を使用すれば、光半導体素子の受光部に対し、鏡筒レンズを平行に取り付けることができる。従って、画像取り込みの際に良好な結像が得られ、鮮明で高画質な画像が得られる。
【図面の簡単な説明】
【図１】本発明の光半導体装置について実施の形態の一例を示す断面図である。
【図２】図１の光半導体装置の平面図である。
【図３】従来の光半導体装置の一例の断面図である。
【図４】従来の光半導体装置の他の例の断面図である。
【符号の説明】
１：光半導体装置
２：基体
２ａ：凹部
２ｂ：底面
２ｃ：側壁部
２ｄ：段差部
３：光半導体素子
３ａ：受光部
４：電極
５：電極パッド
７：樹脂層
８：透光性蓋体
９：支持部材[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical semiconductor device which is a light receiving element such as a photodiode, a line sensor, an image sensor or the like, or an optical semiconductor device provided with an optical semiconductor element having these light receiving portions.
[0002]
[Prior art]
FIG. 3 shows a conventional optical semiconductor device as a light receiving element such as a photodiode (PD), a line sensor, an image sensor, or the like, or an optical semiconductor device provided with an optical semiconductor element having these light receiving portions. 3, reference numeral 101 denotes an optical semiconductor device mainly including a base 102, an optical semiconductor element 103, and a light-transmitting lid 108. 102a is a concave portion formed on the upper main surface of the base 102, 102b is a bottom surface of the concave portion 102a, 102c is a side wall of the base 102, 103 is an optical semiconductor element mounted on the base 102, and 103a is an upper surface of the optical semiconductor element 103. A light receiving unit 104 provided at the center is an electrode provided on the outer peripheral portion of the upper surface of the optical semiconductor element 103. Reference numeral 105 denotes an electrode pad provided on the outer peripheral portion of the bottom surface 102b of the concave portion 102a of the base 102; 106, a bonding wire; 107, a resin layer provided substantially all around the concave portion 102a on the upper surface of the base 102; Is a translucent lid made of glass or the like.
[0003]
The base 102 constituting the optical semiconductor device 101 is made of ceramics or the like, and a separate frame-shaped side wall 102c is provided on the outer peripheral portion of the upper surface of the bottom plate of the base 102. The bottom plate and the side wall 102c of the base 102 may be integrally formed. An electrode pad 105 is provided on the outer periphery of the bottom surface 102b of the concave portion 102a of the base 102.
[0004]
The optical semiconductor element 103 is placed on and adhered to the bottom surface 102 b of the base 102, and an electrode 104 is provided on the outer periphery of the upper surface of the optical semiconductor element 103. The electrode 104 and the electrode pad 105 are electrically connected by a bonding wire 106 made of Au, Al, or the like. Further, a translucent lid 108 is adhered to the upper surface of the side wall 102c of the base 102 via the resin layer 107 (for example, see Patent Document 1 below).
[0005]
[Patent Document 1]
JP-A-5-323230
[Problems to be solved by the invention]
However, in the above-described conventional optical semiconductor device 101, the thickness of the base 102 as a bottom plate on which the optical semiconductor element 103 is mounted, the thickness of the side wall 102c provided so as to surround the optical semiconductor element 103, and the optical semiconductor element 103 A resin layer for mounting and bonding a translucent lid 108 made of glass or the like having substantially the same shape as the outer shape of the upper surface of the side wall portion 102c on the upper surface of the side wall portion 102c and bonding and sealing. There was a tolerance variation such as the thickness of 107. Therefore, there is a problem that it is difficult to make the upper surface of the optical semiconductor element 103 and the lower surface of the translucent lid 108 parallel.
[0007]
Due to such a problem, for example, when the optical semiconductor device 101 is incorporated in a camera or the like, the surface of the translucent lid 108 is used for alignment between the optical semiconductor device 101 and a lens barrel having a lens. For this reason, the lens of the lens barrel is tilted with respect to the light receiving portion 103a on the upper surface of the optical semiconductor element 103, which causes a problem that a problem occurs in taking in an image.
[0008]
In order to solve this problem, Japanese Patent Application Laid-Open Publication No. H11-163873 discloses a base 202 as a reference surface for positioning the light-transmitting lid 204 so as to be parallel to the optical semiconductor element 203 as shown in FIG. A pair of first reference surfaces 202a provided on the inner side surface of the side wall portion for supporting the bottom surfaces of both ends of the light-transmitting lid 204, and the second reference surface 202a for supporting the central bottom surface of the light-transmitting lid 204. There is proposed an image device 201 which can easily correct the warpage of the translucent lid 204 by having the reference surface 202b.
[0009]
However, in any of the above conventional examples, the thickness tolerance and warpage of the base as the bottom plate on which the optical semiconductor element is mounted, and the side wall provided around the optical semiconductor element on the outer peripheral portion of the upper main surface of the base. Inevitable effects of thickness tolerances and variations in the thickness of the adhesive layer for mounting and bonding the optical semiconductor element, and as a result, tilting of the lens barrel with respect to the light receiving portion on the upper surface of the optical semiconductor element occurs. Had not been resolved.
[0010]
Therefore, the present invention has been completed in view of the above problems, and an object of the present invention is to make the light receiving portion on the upper surface of the optical semiconductor element housed in the optical semiconductor device and the lower surface of the translucent lid parallel. Accordingly, the object is to improve the light receiving characteristics of the optical semiconductor device.
[0011]
[Means for Solving the Problems]
In the optical semiconductor device of the present invention, a concave portion for accommodating the optical semiconductor element is formed on the upper surface, and a wiring conductor to which the electrode of the optical semiconductor element is electrically connected is provided on the inner surface of the concave portion. An optical semiconductor element mounted on the bottom surface of the recess, provided with a light receiving portion at the center of the upper surface and having electrodes formed on the outer peripheral portion, and an upper surface of the substrate An optical semiconductor device comprising: a resin layer provided substantially all around the concave portion; and a light-transmissive lid that is adhered on the resin layer and seals the optical semiconductor element. It is characterized in that three or more support members having substantially the same height are provided at substantially equal intervals from the upper surface of the step portion to the lower surface of the translucent lid.
[0012]
In the optical semiconductor device of the present invention, since three or more support members having substantially the same height are provided at substantially equal intervals from the upper surface of the step portion to the lower surface of the light-transmitting lid, the thickness of the side wall portion of the base is increased. The lower surface of the light-transmissive lid is parallel to the light-receiving portion on the upper surface of the optical semiconductor device, with little effect on tolerances and variations in the thickness of the adhesive layer for bonding the optical semiconductor device to the bottom surface of the concave portion of the base. can do. As a result, when the optical semiconductor device is incorporated in a camera or the like, if the surface of the light-transmitting lid is used to align the lens barrel with the lens and the optical semiconductor device, the light receiving portion of the optical semiconductor element can be used. The lens barrel can be mounted in parallel. Therefore, a good image is obtained at the time of image capturing, and a clear and high-quality image is obtained.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
The optical semiconductor device of the present invention will be described below in detail. FIG. 1 is a sectional view showing an example of an embodiment of the optical semiconductor device of the present invention, and FIG. 2 is a plan view of the optical semiconductor device of FIG. In these figures, reference numeral 1 denotes an optical semiconductor device mainly including a base 2, a frame 2c, an optical semiconductor element 3, a translucent lid 8, and a support member 9. 2a is a concave portion formed on the upper surface of the substrate 2, 2b is a bottom surface of the concave portion 2a, 2c is a side wall portion of the substrate 2, 3 is an optical semiconductor device mounted on the substrate 2, 3a is a central portion of the upper surface of the optical semiconductor device 3 The light-receiving portions 4 provided on the optical semiconductor device 3 are input / output electrodes provided on the outer peripheral portion of the upper surface of the optical semiconductor element 3. Reference numeral 5 denotes an electrode pad which is a part of a wiring conductor provided on the upper surface of the step portion 2d on the inner periphery of the concave portion 2a of the base 2, reference numeral 6 denotes a bonding wire made of Au, Al, or the like, and reference numeral 7 denotes an upper surface of the base 2 A resin layer 8 provided substantially all around the concave portion 2a is a light-transmitting lid made of glass, quartz, sapphire, transparent resin, or the like.
[0014]
In the optical semiconductor device 1 of the present invention, the concave portion 2a is formed on the upper surface, and the electrode pad 5 to which the electrode 4 of the optical semiconductor element 3 is electrically connected is provided on the inner surface of the concave portion 2a. A substrate 2 having a stepped portion 2d formed thereon, an optical semiconductor element 3 mounted on a bottom surface 2b of the concave portion 2a, a light receiving portion 3a provided at a central portion of an upper surface, and an electrode 4 formed at an outer peripheral portion; A resin layer 7 provided substantially all around the concave portion 2a on the upper surface; and a translucent lid 8 bonded to the upper portion of the resin layer 7 to seal the optical semiconductor element 3; In this configuration, three or more support members 9 having substantially the same height are provided at substantially equal intervals from the upper surface to the lower surface of the light-transmitting lid 8.
[0015]
The base 2 constituting the optical semiconductor device 1 is made of ceramics or the like, and a separate frame-shaped side wall 2c is provided on the outer peripheral portion of the upper surface of the bottom plate of the base 2. Further, the bottom plate portion and the side wall portion 2c of the base 2 may be integrated.
[0016]
The optical semiconductor element 3 is placed on the bottom surface 2 b of the base 2 and is fixed by bonding, and an electrode 4 is provided on the outer peripheral portion of the upper surface of the optical semiconductor element 3. The electrode 4 and the electrode pad 5 are electrically connected by a bonding wire 6 made of Au, Al, or the like. Further, the translucent lid 8 is bonded and fixed to the upper surface of the side wall 2 c of the base 2 via the resin layer 7.
[0017]
The support member 9 of the present invention is made of an alumina (Al 2 O 3 ) sintered body, an aluminum nitride (AlN) based sintered body, a silicon carbide (SiC) based sintered body, and a silicon nitride (Si 3 N 4 ) based sintered body. It is made of a ceramic such as a sintered body, a glass ceramic, a metal such as an Fe-Ni-Co alloy, Al, or Cu, or a resin such as an acrylic resin, an epoxy resin, a silicone resin, or a polyetheramide resin. Since the support member 9 is provided between the step portion 2d on the inner periphery of the concave portion 2a of the base 2 and the light-transmitting lid 8, heat generated when the entire optical semiconductor device 1 is mounted on an external circuit board or the like. There is a possibility that the support member 9 expands and stresses the base 2 and the translucent lid 8. For this reason, among the above materials, ceramics having a low coefficient of thermal expansion are preferable. For example, it is preferable to use a ceramic mainly composed of alumina having a coefficient of thermal expansion of about 5 × 10 −6 to 10 × 10 −6 / ° C.
[0018]
As the shape of the support member 9, the height is preferably 300 to 1500 μm, and the cross-sectional shape is a polygonal column having a side having a length of 100 μm to 1 mm, a circular column having a diameter of 100 μm to 1 mm, or An elliptical column shape having an elliptical diameter of 100 μm to 1 mm is preferred.
[0019]
If the height is less than 300 μm, the support member 9 may be lower than the top of the bonding wire 6 and the top of the side wall 2c. If the height exceeds 1500 μm, the thickness of the optical semiconductor device 1 itself increases and the size becomes large, which is not preferable.
[0020]
Regarding the cross-sectional shape of the support member 9, since the support member 9 needs to be installed in a narrow area between the optical semiconductor element 1 and the side wall 2 c on the bottom surface 2 b of the base 2, the length of one side of the cross section in the case of a polygonal column shape It is preferable that the diameter of the cross section is 1 mm or less, the diameter of the cross section is 1 mm or less in the case of a cylindrical shape, and the long diameter of the cross section is 1 mm or less in the case of an elliptical column shape. On the other hand, if the length of one side of the cross section is less than 100 μm in the case of a polygonal column, the diameter of the cross section is less than 100 μm in the case of a column, and if the major axis of the cross section is less than 100 μm in the case of an elliptical column, the support member 9 is thin. Too much, and its workability and workability during installation deteriorate.
[0021]
Therefore, as a more preferable shape of the support member 9, the height is 600 to 1100 μm, and the cross-sectional shape is a polygon having a side length of 200 to 500 μm in the case of a polygonal column, and a circular shape having a diameter of 200 to 500 μm in the case of a column. In the case of an elliptic column, it is preferable that the major axis is an ellipse having a length of 200 to 500 μm.
[0022]
When the optical semiconductor element 3 has a substantially quadrangular shape in plan view, the supporting member 9 is preferably installed at a step 2d on the inner periphery of the concave portion 2a around the optical semiconductor element 3 and near the corner thereof. It is preferable to install three or four pieces at substantially equal intervals for each of the three pieces. This is because, in order to support the light-transmitting lid 8 so as to be parallel to the light receiving portion 3 a of the optical semiconductor element 3, it is preferable to install the light-transmitting lid 8 as much as possible around the optical semiconductor element 3. Yes, and it is difficult to support them in parallel without three or more. The installation intervals of the support members 9 can be set at equal angular intervals with respect to the center of the light receiving section 3a. In the case of three, the interval may be 120 °, and in the case of providing four support members 9a to 9d as shown in FIG. 2, the interval may be 90 °.
[0023]
The upper end surface of the support member 9 is preferably located at a position higher than the upper surface of the side wall portion 2c. Since the resin layer 7 is provided on the upper surface of the side wall portion 2c, the upper end surface of the support member 9 is preferably located at a position higher than the lower end of the resin layer 7. In this case, the support member 9 is placed on the lower surface of the translucent lid 8. It is easier to adhere to Further, it is preferable that the upper end surface of the support member 9 be higher than the lower end of the resin layer 7 and be lower than the upper end of the resin layer 7. When the upper end surface of the support member 9 is higher than the upper end of the resin layer 7, the lower surface of the translucent lid 8 is easily peeled off from the resin layer 7.
[0024]
Further, the shape of the support member 9 may be a shape in which the lower side is thicker than the upper side and the upper end is pointed. In this case, if the supporting member 9 is soft, at least one step is required when finely adjusting the inclination of the translucent lid 8 in a state where the upper end of the supporting member 9 is in contact with the lower surface of the translucent lid 8. When the upper end of the supporting member 9 of the portion is crushed, the translucent lid 8 can be fixed in a state parallel to the light receiving portion 3a of the optical semiconductor element 3. Further, if the support member 9 is hard, at least a part of fine adjustment of the inclination of the translucent lid 8 in a state where the upper end of the support member 9 is in contact with the lower surface of the translucent lid 8 is performed. By penetrating the upper end of the supporting member 9 into the lower surface of the translucent lid 8, the translucent lid 8 can be fixed in a state parallel to the light receiving portion 3a of the optical semiconductor element 3.
[0025]
When the support member 9 is installed, the support member 9 is fixed using an adhesive made of an acrylic resin, an epoxy resin, a silicone resin, a polyetheramide resin, or the like. The upper end surface and / or the lower end surface of the support member 9 may be bonded.
[0026]
The substrate 2 of the present invention is made of an alumina (Al 2 O 3 ) sintered body, an aluminum nitride (AlN) based sintered body, a silicon carbide (SiC) based sintered body, and a silicon nitride (Si 3 N 4 ) based sintered body. Body, ceramics such as glass ceramics, or metals such as Fe-Ni-Co alloys, Fe-Ni alloys, Al and Cu. The side wall 2c may be separate from the base 2, but in this case, it is preferable that the side wall 2c be made of the same material as the base 2.
[0027]
An electrode pad 5 is provided on a step portion 2d on the inner periphery of the concave portion 2a of the base 2, and the electrode pad 5 is formed by a metallized layer formed on the outer surface of the side wall 2c of the base 2, the lower surface of the base 2, and the like. Through a wiring pattern and lead terminals (not shown).
[0028]
The optical semiconductor element 3 of the present invention is a light receiving element such as a PD, a line sensor, an image sensor, a CCD (Charge Coupled Device), an EPROM (Erasable and Programmable ROM), or an optical semiconductor element having these light receiving parts. When bonding the optical semiconductor element 3 to the bottom surface 2b of the base 2, it is fixed using a bonding material made of silver paste or the like, but it is better to make the thickness of the bonding material as thin as possible. Specifically, the thickness of the joining material is preferably 50 μm or less. In this case, the parallelism of the optical semiconductor element 3 to the bottom surface 2b is improved, and the effect of improving the parallelism of the translucent lid 8 to the optical semiconductor element 3 by installing the support member 9 is increased.
[0029]
The resin layer 7 is made of an acrylic resin, an epoxy resin, a silicone resin, a polyetheramide resin, or the like. The resin layer 7 may be mixed with a dark color dye or pigment such as black, brown, dark green, or dark blue in order to block unnecessary external light from entering.
[0030]
【Example】
An embodiment of the optical semiconductor device of the present invention will be described below.
[0031]
The optical semiconductor device 1 of FIGS. 1 and 2 was configured as follows. Using a substrate 2 made of alumina ceramics, an optical semiconductor element 3 made of a CCD, and a translucent lid 8 made of glass, a 30 μm thick silver paste (resin containing silver) is formed on the bottom surface 2 b of the substrate 2. The electrode pad 5 on the bottom surface of the step 2d and the electrode 4 on the upper surface of the optical semiconductor element 3 were connected by a bonding wire 6 made of Au. Next, columnar support members 9a to 9d made of alumina ceramic and having a diameter of 500 μm and a height of 1 mm are adhered to the four corners of the bottom surface of the step portion 2d with an epoxy resin, and the translucent lid 8 is attached to the epoxy system. Bonded with a resin layer 7 made of resin.
[0032]
In addition, as a comparative example, the optical semiconductor device 101 shown in FIG. 3 was manufactured in the same manner as in the above example except that the support members 9a to 9d were not provided.
[0033]
Then, the optical semiconductor device 1 of the present invention was compared with that of the comparative example. In the semiconductor device 101 of the comparative example having no support members 9a to 9d, the parallelism between the light receiving portion 103a of the optical semiconductor element 103 and the translucent lid 108, that is, the light receiving portion 103a and the translucent lid 108 The difference between the maximum value and the minimum value of the gap between them was about 100 μm, but in the optical semiconductor device 1 of the present invention, the difference could be suppressed to 30 μm or less. As a measuring method, a method of measuring the distance between the upper surface of the optical semiconductor element and the lower surface of the light-transmitting lid by a depth of focus using a high-magnification microscope (100 to 400 times) such as a metal microscope is used. Using.
[0034]
It should be noted that the present invention is not limited to the above embodiments and examples, and various changes can be made without departing from the scope of the present invention.
[0035]
【The invention's effect】
In the optical semiconductor device of the present invention, a concave portion for accommodating the optical semiconductor element is formed on the upper surface, and a wiring conductor to which an electrode of the optical semiconductor element is electrically connected is provided on the inner surface of the concave portion. A substrate having a stepped portion, an optical semiconductor element mounted on the bottom surface of the concave portion, a light receiving portion provided in the center of the upper surface, and an electrode formed on the outer peripheral portion; and a periphery of the concave portion on the upper surface of the substrate. And a light-transmitting lid that is adhered on the upper portion of the resin layer and seals the optical semiconductor element, from the upper surface of the step portion to the lower surface of the light-transmitting lid. By providing three or more support members having substantially the same height at substantially equal intervals, the thickness tolerance of the side wall portion of the base and the variation of the thickness of the adhesive layer for bonding the optical semiconductor element to the bottom surface of the concave portion of the base are reduced. Almost unaffected, light transmissive to the light receiving part on the upper surface of the optical semiconductor device The lower surface of the body may be parallel. As a result, when the optical semiconductor device is incorporated in a camera or the like, if the surface of the light-transmitting lid is used to align the lens barrel with the lens and the optical semiconductor device, the light receiving portion of the optical semiconductor element can be used. The lens barrel can be mounted in parallel. Therefore, a good image is obtained at the time of image capturing, and a clear and high quality image is obtained.
[Brief description of the drawings]
FIG. 1 is a sectional view showing an example of an embodiment of an optical semiconductor device of the present invention.
FIG. 2 is a plan view of the optical semiconductor device of FIG.
FIG. 3 is a cross-sectional view of an example of a conventional optical semiconductor device.
FIG. 4 is a cross-sectional view of another example of a conventional optical semiconductor device.
[Explanation of symbols]
1: optical semiconductor device 2: base 2a: concave portion 2b: bottom surface 2c: side wall portion 2d: step portion 3: optical semiconductor element 3a: light receiving portion 4: electrode 5: electrode pad 7: resin layer 8: translucent lid 9 ： Support member
