JP2004129089A

JP2004129089A - Piezoelectric vibrator for surface mounting, its manufacturing, and sheet substrate matrix

Info

Publication number: JP2004129089A
Application number: JP2002293106A
Authority: JP
Inventors: Toshiyuki Taira; 平　敏幸; Yoji Nagano; 永野　洋二; Hiroteru Hirano; 平野　浩輝
Original assignee: Toyo Communication Equipment Co Ltd
Current assignee: Toyo Communication Equipment Co Ltd
Priority date: 2002-10-04
Filing date: 2002-10-04
Publication date: 2004-04-22

Abstract

<P>PROBLEM TO BE SOLVED: To solve a defect such as damage or coming off of an adjusting screw which occurred in the prior art when a sheet substrate matrix is divided into individual pieces by a dicing blade in mass production processes of producing a piezoelectric oscillator for surface mounting by batch processing using the matrix. <P>SOLUTION: The oscillator includes an IC part unit 2 and a piezoelectric vibrator 3 connected to an upper surface of the IC part unit. The IC part unit has an insulating substrate 5 provided on its one surface with a recess 6 for IC part mounting and having two opposing open side walls 10, pads 7 for IC part mounting, adjusting terminals 30 connected to the IC part mounting pads, upper electrodes 11, and external electrodes 9. The adjusting terminals are located in the bottom of the substrate at such positions as avoid interference with the external electrodes, and have a continuity with the IC part mounting pads via through-holes 31 passing through the substrate. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は水晶発振器等の圧電発振器の改良に関し、特にＩＣ部品を搭載したＩＣ部品ユニット上に、パッケージ化された圧電振動子を固定一体化したタイプの表面実装用圧電発振器、その製造方法及びＩＣ部品搭載用のユニットのシート状基板母材に関する。
【０００２】
【従来の技術】
携帯電話機等の移動体通信機器の普及に伴う低価格化及び小型化の急激な進展により、これらの通信機器に使用される水晶発振器等の圧電発振器に対しても低価格化、小型化及び薄型化の要請が高まっている。このような要請に対しては、水晶振動子をパッケージ化するのみならず、周波数調整回路、周波数温度補償回路等を含む発振回路を集積化、ＩＣ化して部品点数を削減している。
図７（ａ）乃至（ｄ）は従来の表面実装用の圧電発振器の外観斜視図、内部構造を示す縦断面図、ＩＣ部品を搭載した絶縁基板の平面図、及び絶縁基板の斜視図である。この圧電発振器１０１は、ＩＣ部品搭載用パッケージ（ＩＣ部品ユニット）１０２上にパッケージ化された圧電振動子１０３を固定したタイプである。
ＩＣ搭載用パッケージ１０２は、セラミック等の絶縁材料から成る絶縁基板１０５の上面中央部に凹陥部１０６を形成し、凹陥部内底面に設けたＩＣ部品搭載用のパッド１０７上にＩＣチップ或いはパッケージ（以下、ＩＣ部品、と言う）１０８を載置し、ＩＣ部品１０８の電極をハンダ等を用いてパッド１０７上に固定した構成を有する。凹陥部１０６を包囲する４面の外壁１１０のうちの対向する２つの外壁の少なくとも一部が開放した開放部１１０Ａとなっている。
また、基板１０５の底面には表面実装用の外部電極１０９が形成され、凹陥部１０６を包囲する外壁１１０上面には上部電極１１１が形成されている。外部電極１０９は図示しない接続導体を介してパッド１０７、或いは上部電極１１１と配線されている。上部電極１１１は、パッド１０７或いは外部電極１０９と図示しない接続導体を介して配線されている。凹陥部１０６内に搭載されたＩＣ部品１０８は、空気と接することによってその電極等に結露等が発生してショートを起こす等の不具合をもたらす虞があるため、凹陥部１０６内に絶縁樹脂１１２を充填（ポッティング）して外気と遮断させる。
圧電振動子１０３は、セラミック等から成る箱形のパッケージ本体１２０の凹陥部１２１内に圧電振動素子１２２を収納してから蓋１２３によって凹陥部１２１を気密封止した構成を有する。圧電振動素子１２２は、水晶基板などの圧電基板の主面上に励振電極を形成したものであり、励振電極から圧電基板の端縁に延びるリード電極を凹陥部１２１内に配置したパッド１２５に接続固定する一方で、パッケージ本体１２０の底面にはパッド１２５と導通する底面電極１２６を露出形成している。底面電極１２６は、ＩＣ搭載用パッケージ１０２の上部電極１１１と一対一に対応してハンダ或いは導電性接着剤等によって接続固定される。
【０００３】
ところで、上記の如き構成を備えた圧電発振器においては、凹陥部１０６の内底面のパッド１０７上に搭載したＩＣ部品１０８内の記憶領域に所要の係数を書き込むことにより発振周波数や温度補償特性を調整するための調整用端子１３０を設ける場所として、絶縁基板１０５の側面、特に開放部１１０Ａに対応する位置にある側壁外面を選定する。即ち、調整用端子１３０は、側壁外面に凹所１３１を形成して金属片１３２を埋込み、更に金属片１３２を各パッド１０７から伸びる配線パターン１０７ａと導通させた構成を備えている。この調整用端子１３０に対して調整機器から伸びるプローブピン等を当接させることにより、ＩＣ部品１０８内の各種回路に対する設定値の読み出し、書込み、書き換えなどを行うことが可能となる。
ところで、上記の如き圧電発振器は、大面積の絶縁基板シートを用いたバッチ処理によって量産される。図８（ａ）（ｂ）及び（ｃ）はシート状基板母材の構成を示す要部平面図、及び要部縦断面図である。
このシート状基板母材１３５は、上記の如き電極構成を備えた複数の絶縁基板１０５を複数個シート状に連結した構成を備えている。絶縁基板１０５をシート状に連結した絶縁基板シート１４０は、３枚のセラミックシート１４１、１４２、１４３を積層一体化した構成を備えている。第１層目のセラミックシート１４１の下面には外部電極１０９が形成され、第１層目と第２層目のセラミックシート１４１、１４２間であって絶縁基板１０５が存在しない廃棄領域Ａには、電解メッキ用に使用する配線パターン１５０が配線され、各メッキ用配線パターン１５０は同じく廃棄領域Ａに設けた電解メッキ用のパッド１５１と接続されている。また、ＩＣ搭載用の各パッド１０７から伸びるメッキ用配線パターン１０７ｂは直近に位置する配線パターン１５０と接続されている。電解メッキ用のパッド１５１及び電解メッキ用配線パターン１５０は、ＩＣ部品搭載用パッド１０７の表面に導電性の良好な金や銅を電解メッキする際に使用される。
【０００４】
一方、ＩＣ搭載用の各パッド１０７と配線パターン１０７ａを介して接続されている調整用端子１３０は、絶縁基板１０５の端縁（開放部１１０Ａ側端縁）に貫通形成したスルーホール（或いは貫通孔）内に金属片を埋め込んでから、絶縁基板間、或いは絶縁基板と廃棄領域Ａ間の境界線に沿って、表裏両面側から夫々後述するブレイク溝を予め形成しておくことにより形成される。
第３層目のセラミックシート１４３は、各絶縁基板１０５の凹陥部１０６を形成するための外壁１１０を形成するようにレイアウトされ、凹陥部１０６内底面にはＩＣ部品搭載用パッド１０７を有すると共に、外壁１１０の上面には上部電極１１１が形成される。パッド１０７と各電極１０９、１１１間は接続導体（内部導体）１５５によって電気的に接続されている。
各絶縁基板１０５間の境界線、並びに絶縁基板領域と廃棄領域Ａとの境界線に沿った絶縁基板シート１４０の上面、及び下面には、夫々折り割りするためのブレイク溝１５６ａ、１５６ｂが形成されている。ブレイク溝を利用した折り割りによった場合、ダイシングブレードによる切断によった場合に比して、切断面が滑らかとなり、バリが形成されにくくなる。このため、調整用端子１３０を構成する金属片１３２を分割する際に金属片１３２が凹所１３１から脱落する等の不具合が生じにくい、という利点を有する。
各ブレイク溝１５６ａ、１５６ｂは、電解メッキ用の配線パターン１５０を寸断することがないように、その深さが調整されている。絶縁基板間をバリがないように綺麗に折り割りするためには図示の如く上側のブレイク溝１５６ａは第３層から第２層のセラミックシートにまで達する深さを有する必要がある。一方、第１層のセラミックシート１４１の下面に形成される下側のブレイク溝１５６ｂは、配線パターン１５０を寸断しない程度に深さ設定される。
しかし、このような３層構造の絶縁基板シート１４０にあっては、第１層のセラミックシート１４１の肉厚分だけ、絶縁基板シートが厚くなり、完成した圧電発振器の高さが大きくなるという問題を有する。
このような問題を解決し、圧電発振器の薄型化を促進するため、最近では、図９に示すように、２層構造の絶縁基板シートを備えたシート状基板母材１３５が使用されている。
【０００５】
この２層構造の絶縁基板シート１４０は、２枚のセラミックシート１４１、１４２を積層した構成を備えている。第１層目のセラミックシート１４１の下面には外部電極１０９が形成され、第１層目と第２層目のセラミックシート１４１、１４２間であって絶縁基板１０５が存在しない廃棄領域Ａ（図８（ｂ）参照）には、電解メッキ用に使用する配線パターン１５０が配線され、各メッキ用配線パターン１５０は同じく廃棄領域Ａに設けた電解メッキ用のパッド１５１と接続されている。また、ＩＣ搭載用の各パッド１０７から伸びるメッキ用配線パターン１０７ｂは直近に位置するメッキ用配線パターン１５０と接続されている。電解メッキ用のパッド１５１及び電解メッキ用配線パターン１５０は、ＩＣ部品搭載用パッド１０７、各電極１０９、１１１の各表面に導電性の良好な金や銅を電解メッキする際に使用される。
第２層目のセラミックシート１４２は、各絶縁基板１０５の凹陥部１０６を形成するための外壁１１０を形成するようにレイアウトされ、凹陥部１０６内底面にはＩＣ部品搭載用パッド１０７を有すると共に、外壁１１０の上面には上部電極１１１が形成される。各電極１０９、１１０、１１１間は接続導体（内部導体）１５５によって電気的に配線されている。
【０００６】
このような構成を備えた２層構造のシート状基板母材１３５において、折り割り用のブレイク溝を形成するとすれば、図示の如く、各絶縁基板１０５間の境界線、並びに絶縁基板領域と廃棄領域Ａとの境界線に沿ったシート状基板母材の上面、及び下面に夫々ブレイク溝１５６ａ、１５６ｂを形成する必要がある。しかし、分割面にバリ等が発生しないようにするためには、いずれか一方のブレイク溝を両セラミックシートの接合面を越えて深く形成する必要があり、メッキ用配線パターン１５０を寸断する結果となる。このため、２層構造のシート状基板母材１３５には、折り割り用のブレイク溝を形成することができず、ダイシングブレードによる切断方法しか採用し得なかった。
しかしながら、ダイシングブレードによる切断によった場合には、切断面にバリが発生し易く、特に調整用端子１３０を形成するためにスルーホール内に埋め込まれた金属片をスムーズに切断することが難しくなり、金属片の変形、脱落といった不具合をもたらしていた。
つまり、絶縁基板の薄型化を図るために、２層構造の絶縁基板シート１４０を採用したシート状基板母材１３５を用いた場合には、基板間を分割するためのブレイク溝を採用できない一方で、ダイシングにより分割する場合には、切断面に形成されるバリによって調整用端子が形成不良となり、不良品発生率が増大するという問題があった。
更に、圧電発振器を構成する絶縁基板の外面に調整用端子を設けること自体が、発振器の小型化やレイアウトの自由度を妨げる結果をもたらしている。即ち、発振器を小型化するために絶縁基板の平面積や高さ寸法が極限されてくると、調整用端子を配置するスペースの確保が困難となり、無理に配置しようとすれば、他の電極や配線パターン等の配置、配回しのための設計の自由度が大きな制限を受ける結果となる。
【０００７】
【発明が解決しようとする課題】
本発明は上記に鑑みてなされたものであり、絶縁基板上にＩＣ部品を搭載したＩＣ部品ユニットと、該ＩＣ部品ユニット上に固定されるパッケージ化された圧電振動子と、から成る圧電発振器を、シート状基板母材を使用したバッチ処理によって量産する過程において、シート状基板母材をダイシングブレードによって個片に分割する際に従来発生していた不具合である調整用端子の損傷、脱落という不具合を解消することができる表面実装型圧電発振器、その製造方法、及びシート状基板母材を提供することを目的とする。
特に、圧電発振器の薄型化を図るために絶縁基板シートを２層構造にした場合、層間に配線されるメッキ用配線パターンの寸断を回避する必要から折り割り用のブレイク溝を形成できず、絶縁基板間の切断に際してはダイシングブレードによらざるを得ないが、ダイシングブレードによって切断した場合には絶縁基板間の切断面にバリが発生し、切断面に調整用端子を構成する金属片が存在する場合には金属片の損傷、脱落をもたらし、良品率が低下する虞があるが、本発明では、調整用端子を絶縁基板端面を回避した位置に設けることにより、このような従来の不具合を解消することができる。
また、本発明の他の目的は、従来調整用端子を圧電発振器を構成する絶縁基板の外面に設けていたことによって発生した調整用端子配置のためのレイアウトの複雑化、小型化に対する障害等の問題を解決することにある。
【０００８】
【課題を解決するための手段】
上記課題を解決するため、請求項１の発明は、対向する２つの側壁が開放したＩＣ部品搭載用の凹陥部を一面に有した絶縁基板、該凹陥部の内底面に形成したＩＣ部品搭載用パッド、該ＩＣ部品搭載用パッドと接続された調整用端子、前記凹陥部を挟んで対向する２つの外壁上部に配置した上部電極、前記絶縁基板の外底部に露出形成した表面実装用の外部電極、前記ＩＣ部品搭載用パッドと上部電極と外部電極とを配線する接続導体、及び前記ＩＣ部品を被覆するために該凹陥部内に充填された樹脂、を備えたＩＣ部品ユニットと、前記ＩＣ部品ユニット上面に載置された際に前記上部電極上に接続される底部電極を備えたパッケージ、及び該パッケージ内に気密収納された圧電振動素子、を備えた圧電振動子と、を有し、前記調整用端子は、前記絶縁基板の底部であって、前記外部電極と干渉しない位置に配置され、前記絶縁基板を貫通するスルーホールを介して前記ＩＣ部品搭載用パッドと導通していることを特徴とする。
ＩＣ部品側の電極と夫々接続されるＩＣ部品搭載用パッドから引き出された調整用端子は、ＩＣ部品の作動状態の試験や、特性値の調整等のために利用されるが、調整用端子を絶縁基板の側面に設ける場合にはバッチ処理による製造過程で種々の問題を引き起こす原因となる。そこで、本発明では、調整用端子を絶縁基板の裏面に設けることにより、シート状絶縁基板母材を個片に切断する際に発生し易い調整用端子の脱落、損傷等という問題を解消した。
請求項２の発明は、前記絶縁基板は、２枚の絶縁シートを積層した構成を備えていることを特徴とする。
底面に外部電極を備えた第１層の絶縁シートと、凹陥部を挟んで対向配置された２つの外壁を形成する第２層の絶縁シートから絶縁基板を構成することにより薄型化を達成できる。
【０００９】
請求項３の発明は、対向する２つの側壁が開放したＩＣ部品搭載用凹陥部を一面に有した絶縁基板を複数個シート状に連結した絶縁基板シートと、前記各絶縁基板の各凹陥部の内底面に形成したＩＣ部品搭載用パッドと、前記各ＩＣ部品搭載用パッドと接続された調整用端子と、前記各凹陥部を挟んで対向配置された２つの外壁上部に配置した上部電極と、前記各絶縁基板の各外底部に形成した表面実装用の外部電極と、前記各ＩＣ部品搭載用パッドと各上部電極と各外部電極とを配線する接続導体と、を備えたシート状基板母材であって、前記シート状基板母材は、底部に前記外部電極を備えるとともに上面に前記ＩＣ搭載用パッドを備えた第１の絶縁シート上に、前記外壁を構成する第２の絶縁シートを積層一体化した構成を備えるとともに、第１の絶縁シートの廃棄領域上には前記各ＩＣ搭載用パッド、前記上部電極、及び前記外部電極と夫々導通する電解メッキ用パターンが形成されると共に、第２の絶縁シートの廃棄領域上には電解メッキ用パターンと接続された電解メッキ用パッドが形成され、前記各調整用端子は、前記第１の絶縁シートの底部であって、前記各外部電極と干渉しない位置に配置され、前記第１の絶縁シートを貫通するスルーホールを介して前記各ＩＣ部品搭載用パッドと導通していることを特徴とする。
このような構成を備えたシート状基板母材を用いた場合には、バッチ処理によって個々の工程を実施して行くことにより、歩留まりよく圧電発振器を量産することができる。
請求項４の発明は、請求項３に記載のシート状基板母材を用いて請求項１又は２に記載の表面実装型圧電発振器を製造する方法であって、前記シート状基板母材を電解液中に浸漬して前記電解メッキ用パッドから通電することにより、前記ＩＣ部品搭載用パッド、上部電極、及び外部電極上に金属を夫々電解メッキする工程と、前記シート状基板母材を構成する各絶縁基板のＩＣ部品搭載用パッド上にＩＣ部品を搭載する工程と、前記凹陥部内に樹脂を充填してＩＣ部品を樹脂被覆する工程と、前記各絶縁基板の上部電極上に、前記各パッケージの底部電極を接続することにより前記圧電振動子を搭載する工程と、前記各工程を経た前記シート状基板母材を、ダイシングにより圧電発振器の個片に分割すると共に、前記廃棄領域を切り離す工程と、を備えたことを特徴とする。
大面積のシート状基板母材を用いて、順次ＩＣ部品搭載、樹脂充填、圧電振動子搭載といった工程を順次実施して行くことにより、請求項１及び２に記載の表面実装用圧電発振器を多数連結した構造体を形成することができ、この構造体を個片毎にダイシングすることによって、底面に調整用端子を備えた圧電発振器を歩留まりよく量産することが可能となる。
【００１０】
請求項５の発明に係る表面実装型圧電発振器は、対向する２つの側壁が開放したＩＣ部品搭載用の凹陥部を一面に有した絶縁基板、該凹陥部の内底面に形成したＩＣ部品搭載用パッド、該ＩＣ部品搭載用パッドと調整用端子とを接続する接続導体と、前記凹陥部を挟んで対向する２つの外壁上部に配置した上部電極、前記絶縁基板の外底部に露出形成した表面実装用の外部電極、前記ＩＣ部品搭載用パッドと上部電極と外部電極とを配線する接続導体、及び前記ＩＣ部品を被覆するために該凹陥部内に充填された樹脂、を備えたＩＣ部品ユニットと、前記ＩＣ部品ユニット上面に載置された際に前記上部電極上に接続される底部電極を備えたパッケージ、及び該パッケージ内に気密収納された圧電振動素子、を備えた圧電振動子と、を有し、前記絶縁基板には、前記調整用端子が配置されていないことを特徴とする。
調整用端子を絶縁基板自体に設けるのではなく、シート状基板母材を用いた製造工程において最終的に廃棄される廃棄領域に設けておき、ＩＣ部品搭載、樹脂充填、圧電振動子搭載の各工程を完了した後で、各個片に隣接配置した廃棄領域上に設けた調整用端子を利用して調整作業を行い、調整完了後に個片毎に分割する際には、廃棄領域を廃棄する。このため、圧電発振器を構成する絶縁基板側に調整用端子を設ける必要がなくなる分だけ、絶縁基板上に設ける電極、パッド、配線などのレイアウト自由度が高まる。また、廃棄領域上に設ける調整用端子の面積を大きくできるので、プローブピンを当接させることによる調整作業をし易くすることができる。
【００１１】
請求項６の発明に係るシート状基板母材は、対向する２つの側壁が開放したＩＣ部品搭載用凹陥部を一面に有した絶縁基板を複数個シート状に連結した絶縁基板シートと、前記各絶縁基板の各凹陥部の内底面に形成したＩＣ部品搭載用パッドと、前記各ＩＣ部品搭載用パッドと接続導体を介して接続された調整用端子と、前記各凹陥部を挟んで対向配置された２つの外壁上部に配置した上部電極と、前記各絶縁基板の各外底部に形成した表面実装用の外部電極と、前記各ＩＣ部品搭載用パッドと各上部電極と各外部電極とを配線する接続導体と、を備えたシート状基板母材であって、前記シート状基板母材は、各絶縁基板の前記凹陥部の２つの開放部のうちの少なくとも一方を閉止する廃棄領域を有し、前記各廃棄領域上に前記調整用端子を配置したことを特徴とする。
この発明によれば、請求項５に記載した如く、絶縁基板側に調整用端子を設けない場合には、シート状基板母材側に設けた廃棄領域に調整用端子を設けておくことにより、ＩＣ部品の調整作業を含めた製造工程を効率的に行うことが可能となる。また、凹陥部の開放部を廃棄領域により閉止した構造であるため、樹脂充填時に樹脂が外部に流出する虞がなくなる。一つの廃棄領域上に、その両側に位置する各絶縁基板上のＩＣ搭載用パッドと夫々接続された調整用端子を配置することにより、廃棄領域の個数を減少させて、シート状基板母材の無駄を少なくして有効利用できる。
請求項７の発明に係る製造方法は、請求項６に記載のシート状基板母材を用いて請求項５に記載の表面実装型圧電発振器を製造する方法であって、前記シート状基板母材を構成する各絶縁基板のＩＣ部品搭載用パッド上にＩＣ部品を搭載する工程と、前記凹陥部内に樹脂を充填してＩＣ部品を樹脂被覆する工程と、前記各絶縁基板の上部電極上に、前記各パッケージの底部電極を接続することにより前記圧電振動子を搭載する工程と、前記各工程を経た前記シート状基板母材を、ダイシングにより圧電発振器の個片に分割すると共に、前記廃棄領域を切り離す工程と、を備えたことを特徴とする表面実装型圧電発振器の製造方法。
これによれば、請求項５に記載の圧電発振器を生産性よく量産することができる。
【００１２】
【発明の実施の形態】
以下、本発明を図面に示した実施の形態により詳細に説明する。
図１（ａ）（ｂ）（ｃ）及び（ｄ）は本発明の一実施形態に係る表面実装用電子部品（圧電発振器）の外観斜視図、内部構造を示す縦断面図、要部平面図及び絶縁基板の斜視図である。
この表面実装用圧電発振器１は、ＩＣ部品搭載用パッケージ（ＩＣ部品ユニット）２上にパッケージ化された圧電振動子３を固定したタイプである。
ＩＣ搭載用パッケージ２は、セラミック等の絶縁材料から成る絶縁基板５の上面中央部に溝状の凹陥部６を形成し、凹陥部内底面に設けたＩＣ部品搭載用パッド７上にＩＣチップ或いはパッケージ（以下、ＩＣ部品、と言う）８を載置し、ＩＣ部品８の電極をハンダ等を用いてＩＣ部品搭載用パッド７上に固定した構成を有する。凹陥部６を包囲する４面の外壁１０のうちの対向する２つの外壁の少なくとも一部が開放した開放部１０Ａとなっている。
また、絶縁基板５の底面には表面実装用の外部電極９が形成され、凹陥部６を挟んで対向配置された２つの外壁１０上面には上部電極１１が形成されている。外部電極９は図示しない接続導体を介してＩＣ搭載用パッド７、又は上部電極１１と配線されている。上部電極１１は、ＩＣ搭載用パッド７又は外部電極９と図示しない接続導体を介して配線されている。凹陥部６内に搭載されたＩＣ部品８は、空気と接することによってその電極等に結露等が発生してショートを起こす等の不具合をもたらす虞があるため、凹陥部６内に絶縁樹脂１２を充填（ポッティング）して外気と遮断させる。絶縁樹脂１２は、インジェクタ等によって溶融した状態でＩＣ部品８の外面全体を被覆するように凹陥部６内に充填され、その後硬化する。
圧電振動子３は、セラミック等から成る箱形のパッケージ本体２０の凹陥部２１内に圧電振動素子２２を収納してから蓋２３によって凹陥部２１を気密封止した構成を有する。圧電振動素子２２は、水晶基板などの圧電基板の主面上に励振電極を形成したものであり、励振電極から圧電基板の端縁に延びるリード電極を凹陥部２１内に配置したパッド２５に接続固定する一方で、パッケージ本体２０の底面にはパッド２５と導通する底面電極２６を露出形成している。底面電極２６は、ＩＣ搭載用パッケージ２の上部電極１１と一対一に対応してハンダ或いは導電性接着剤等によって接続固定される。
【００１３】
ところで、上記の如き構成を備えた本発明の圧電発振器においては、凹陥部６の内底面のＩＣ搭載用パッド７上に搭載したＩＣ部品８内の記憶領域に所要の係数を書き込むことにより発振周波数や温度補償特性を調整するための調整用端子（入力用端子、或いは試験用端子）３０を設ける場所として、絶縁基板５の裏面、特に凹陥部の内底面と対面する位置にある裏面を選定する。
即ち、調整用端子３０は、各パッド７から伸びる配線パターン７ａ上に貫通形成したスルーホール（或いは貫通孔）３１内に導体（金属）３２を充填した構成を有し、この導体３２の絶縁基板裏面側部分を調整用端子３０としている。この調整用端子３０に対して調整機器から伸びるプローブピン等を当接させることにより、ＩＣ部品８内の各種回路に対する設定値の読み出し、書込み、書き換え等を行うことが可能となる。
このように本発明の圧電発振器の特徴的な構成は、ＩＣ部品搭載用の絶縁基板５の凹陥部内底面に設けたＩＣ部品搭載用のパッド７から伸びる調整用端子３０を絶縁基板５の裏面であって外部電極９と干渉しない位置に露出配置した構成にある。
このため、後述するシート状基板母材を用いたバッチ処理による圧電発振器個片の製造において、圧電発振器を個片に分割する際にダイシングブレードを用いた切断を行ったとしても、調整用端子３０は絶縁基板の裏面に位置するため、ダイシング時に切断面に形成されるバリ等の影響を受ける虞が皆無となる。
なお、図１に示したＩＣ部品搭載用パッケージ２は、絶縁基板の上面に凹陥部６を形成した例を示したが、凹陥部６を絶縁基板の下面に設け、凹陥部６を挟んで対向配置された２つの外壁の下面に外部電極を、上面に上部電極を夫々設け、凹陥部６内にＩＣ部品を搭載した後で樹脂を充填し、その後上部電極を設けた絶縁基板上面側に圧電振動子を搭載するようにしてもよい。
なお、以下の実施形態は全て図１に図示した如く絶縁基板上面側に凹陥部を設けた例を中心として説明する。
【００１４】
次に、上記の如き圧電発振器は、大面積のシート状基板母材を用いたバッチ処理によって量産される。図２（ａ）（ｂ）（ｃ）及び（ｄ）はシート状基板母材の構成を示す要部平面図、及び要部縦断面図である。
このシート状基板母材３５は、上記の如き電極構成を備えた複数の絶縁基板５を複数個シート状に連結した構成を備えている。即ち、シート状基板母材３５は、２枚のセラミックシート（絶縁シート）４１、４２を積層一体化した絶縁基板シート４０に、上記の如きパッド７、電極９、１１、配線パターン７ａ、７ｂ、９ａ、１１ａ等を形成した構成を備えている。第１層目のセラミックシート４１の下面には外部電極９が形成され、第１層目と第２層目のセラミックシート４１、４２間であって絶縁基板５が存在しない廃棄領域Ａには、電解メッキ用に使用する配線パターン５０が配線され、各メッキ用配線パターン５０は同じく第２層目のセラミックシート４２の廃棄領域Ａ上に設けた電解メッキ用のパッド５１と接続されている。また、ＩＣ搭載用の各パッド７、外部電極９及び上部電極１１から夫々伸びるメッキ用配線パターン７ｂ、９ａ、１１ａは、夫々直近に位置する配線パターン５０と接続されている。電解メッキ用のパッド５１及び電解メッキ用配線パターン５０は、ＩＣ部品搭載用パッド７、各電極９、１１の各表面に導電性の良好な金や銅を電解メッキする際に使用される。
一方、ＩＣ搭載用の各パッド７と配線パターン７ａを介して接続されている調整用端子３０は、絶縁基板５の凹陥部適所に貫通形成したスルーホール（或いは貫通孔）３１内に金属片３２を埋め込むことにより形成される。そして、スルーホール３１内の金属片３２の底部にプローブピンを当接させて調整、測定等を行う。
【００１５】
第２層目のセラミックシート４２は、各絶縁基板５の凹陥部６を形成する２つの外壁１０を形成するようにレイアウトされ、凹陥部６内底面にはＩＣ部品搭載用パッド７を有すると共に、外壁１０の上面には上部電極１１が形成される。パッド７と各電極９、１１間は接続導体（内部導体）５５によって電気的に接続されている。
このような構成を備えたシート状基板母材３５を構成する各絶縁基板５の各ＩＣ搭載用パッド７上にＩＣ部品８を夫々搭載してから樹脂１２を充填し、更に各絶縁基板５上に圧電振動子３を固定する。
その後、圧電振動子３を搭載したシート状基板母材３５を個片間の境界線に沿って切断することにより、圧電発振器個片を得る。
各絶縁基板５間の境界線、並びに絶縁基板領域と廃棄領域Ａとの境界線に沿った絶縁基板シートの上面、及び下面には、格別の溝等は形成されておらず、例えば画像認識手段を備えたダイシングマシンによって境界線に沿った経路（切断線Ｌ）にて切断が行われる。ダイシングによった場合、切断面にバリが発生することがあるが、本実施形態のシート状基板母材３５は、各絶縁基板５間の境界線に調整用端子等が存在しないため、切断面にバリが発生しても電気的な特性に影響を与える虞が少ない。
なお、凹陥部６の開放部１０Ａ側の廃棄領域Ａを外壁１０と同等の高さに設定することにより、樹脂１２を凹陥部内に充填した時に当該廃棄領域Ａが樹脂の流出を阻止するせき止め手段として機能することとなる。
【００１６】
次に、シート状基板母材３５を用いた圧電発振器の製造方法は次の如き各工程から成る。
即ち、まず、図１に示した如き構成を備えたシート状基板母材３５を電解液中に浸漬して電解メッキ用パッド５１から通電することにより、ＩＣ部品搭載用パッド７、及び各電極９、１１上に導電性の高い金属を電解メッキする工程を実施する。これらのパッド、電極は、予めタングステン等によって構成され、それ自体は、半田とのなじみがよくないので、ニッケル等を介して金、或いは銅などを成膜する。
次に、シート状基板母材３５を構成する各絶縁基板５のＩＣ部品搭載用パッド７上にＩＣ部品８を搭載する工程を実施する。ＩＣ部品搭載用パッド７上に予め所定のマスクを用いてクリーム半田を塗布しておき、リフローによってＩＣ部品８を搭載する。
次に、凹陥部６内に溶融樹脂１２を充填してＩＣ部品８を被覆してから、各絶縁基板５の上部電極１１上に、各圧電振動子３の底部電極２６を半田接続することにより圧電振動子３を搭載する。
最後に、各工程を経たシート状基板母材３５を、ダイシングにより圧電発振器の個片に分割すると共に、廃棄領域Ａを切り離す工程を実施する。
上記の如き工程を実施することにより、図１に示した如き構成の表面実装用圧電発振器を生産性よく製造することが可能となる。
【００１７】
次に、図３は本発明の他の実施形態に係る表面実装用圧電発振器であり、図１の実施形態と同一部分には同一符号を付して説明するが、本実施形態は、絶縁基板５の外面に調整用端子が存在しない点が特徴的である。
即ち、この表面実装用圧電発振器１は、ＩＣ部品搭載用パッケージ（ＩＣ部品ユニット）２上にパッケージ化された圧電振動子３を固定したタイプである。
ＩＣ搭載用パッケージ２は、セラミック等の絶縁材料から成る絶縁基板５の上面中央部に溝状の凹陥部６を形成し、凹陥部内底面に設けたＩＣ部品搭載用パッド７上にＩＣチップ或いはパッケージ（以下、ＩＣ部品、と言う）８を載置し、ＩＣ部品８の電極をハンダ等を用いてＩＣ部品搭載用パッド７上に固定した構成を有する。凹陥部６を包囲する４面の外壁１０のうちの対向する２つの外壁の少なくとも一部が開放した開放部１０Ａとなっている。
また、絶縁基板５の底面には表面実装用の外部電極９が形成され、凹陥部６を挟んで対向配置された２つの外壁１０上面には上部電極１１が形成されている。外部電極９は図示しない接続導体を介してＩＣ搭載用パッド７、及び上部電極１１と接続されている。上部電極１１は、ＩＣ搭載用パッド７及び外部電極９と図示しない接続導体を介して接続されている。凹陥部６内に搭載されたＩＣ部品８は、空気と接することによってその電極等に結露等が発生してショートを起こす等の不具合をもたらす虞があるため、凹陥部６内に絶縁樹脂１２を充填（ポッティング）して外気と遮断させる。絶縁樹脂１２は、インジェクタ等によって溶融した状態でＩＣ部品８の外面全体を被覆するように凹陥部６内に充填され、その後硬化する。
圧電振動子３の構成は、図１の実施形態と同様である。
【００１８】
ところで、上記の如き構成を備えた本発明の圧電発振器の特徴的な構成は、絶縁基板５のいずれの部分にも調整用端子を配置していない点にある。即ち、圧電発振器には、通常、凹陥部６の内底面のＩＣ搭載用パッド７上に搭載したＩＣ部品８内の記憶領域に所要の係数を書き込むことにより、発振周波数や温度補償特性を調整するための調整用端子（入力用端子、或いは試験用端子）が、外周面に設けられている。このタイプの圧電発振器にあっては、完成した個々の圧電発振器に設けた調整用端子に対してプローブピンを当接して調整作業を行うことになる。これに対して本実施形態に係る圧電発振器にあっては、後述するように圧電発振器自体には調整用端子を設けず、圧電発振器をバッチ処理により生産する際に使用するシート状基板母材の廃棄領域上にのみ調整用端子を設けておき、各絶縁基板の直近に位置する廃棄領域上の調整用端子と個々の絶縁基板上のＩＣ部品搭載用パッドとを電気的に接続させておく。そして、シート状基板母材に対するＩＣ部品の組み付け、樹脂充填、圧電振動子の搭載等を完了した後、個片に分割する前に、廃棄領域上の調整用端子を利用した調整作業を完了しておく。
【００１９】
次に、図４（ａ）及び（ｂ）はシート状基板母材を用いて図３の圧電発振器を製造する手順を説明するための要部平面図（樹脂の一部を除去してＩＣ部品を露出させた状態）、及びＷ−Ｗ断面図である。
このシート状基板母材６０は、上記の如き電極構成を備えた複数の絶縁基板５を複数個シート状に連結すると共に、絶縁基板５の端縁に沿った適所に廃棄領域６１を配置した構成を備えている。シート状基板母材６０は、複数枚のセラミックシート（絶縁シート）を積層一体化した絶縁基板シート６２に、上記の如きパッド７、電極９、１１等を形成した構成を備えている。
即ち、各凹陥部６同志が互いに連通するように２組の絶縁基板５を横方向に隣接配置すると共に、２個の絶縁基板５の外側端縁に沿って細幅帯状の廃棄領域６１を密着配置することにより、両絶縁基板５の凹陥部外側を廃棄領域６１によって閉止した構成を備えている。このような２個の絶縁基板５を縦方向及び横方向に複数組連設することにより、一枚のシート状基板母材６０を形成している。
個々の絶縁基板５の凹陥部６の内底面にはＩＣ部品搭載用パッド７が形成され、その下面には外部電極９が夫々形成され、外壁１０の上部には上部電極１１が形成されている。パッド７、外部電極９、上部電極１１間は接続導体を介して導通されている。
廃棄領域６１は隣接配置された２つの絶縁基板５の各凹陥部６の外側端縁を閉止する形で配置されているため、パッド７上にＩＣ部品８を搭載してから樹脂１２を充填する際のせき止め手段として機能する。また、廃棄領域６１上に形成した調整用端子７０は、近接する凹陥部６内のＩＣ搭載用パッド７と、接続導体７１を介して一対一の関係で導通されている。調整用端子７０は、必要に応じて廃棄領域６１の下面側にも配置することが可能である。廃棄領域６１上の各調整用端子７０は、廃棄領域６１の左右両側に位置する絶縁基板上のパッド７と夫々接続されている。
なお、本実施形態では、２個の絶縁基板５を横方向に連設配置すると共に、その両外側端縁に沿って夫々廃棄領域６１を配置した例を示したが、これは一例であり、個々の絶縁基板の両側に沿って廃棄領域を配置するようにしてもよい。
【００２０】
このような構成を備えたシート状基板母材６０を構成する各絶縁基板５の各ＩＣ搭載用パッド７上にＩＣ部品８を夫々搭載してから樹脂１２を充填し、更に各絶縁基板５上に圧電振動子３を固定する。
その後、圧電振動子３を搭載したシート状基板母材６０を個片間及び個片と廃棄領域間の各境界線Ｌに沿って切断することにより、圧電発振器個片を得る。
この切断工程において、パッド７と調整用端子７０とを接続する接続導体７１は切断され、絶縁基板５側に接続用端子７０が残存することはない。
なお、各絶縁基板５側に搭載されたＩＣ部品８内の各種回路に対する設定値の測定、調整作業は、分割前の状態において、各調整用端子７０に対して調整機器のプローブピンを当接させることにより実施される。
この実施形態においては、絶縁基板とは別個の領域である廃棄領域６１上に調整用端子を設けるため、個々の調整用端子の面積を広く確保することができ、プローブピンを利用した調整作業が正確且つ容易となる。
図５はシート状絶縁基板の他の構成例を示す平面図であり、この実施形態に係るシート状絶縁基板が図４の実施形態と異なる点は、廃棄領域６１を凹陥部６の開放部１０Ａ側に設けずに、各外壁１０の外側に配置し、更に絶縁基板間に廃棄領域６１を介在させずに横方向に隣接配置させた構成にある。
廃棄領域６１の上面、又は／及び下面に調整用端子７０を配置し、接続導体７１を介して凹陥部内のＩＣ搭載用パッド７と接続する点と、図６（ａ）（ｂ）のように圧電振動子３を搭載し、調整作業を完了した後で、絶縁基板との境界線Ｌに沿って切断し、廃棄領域６１を廃棄する点は、上記実施形態と同様である。
【００２１】
【発明の効果】
以上のように本発明によれば、圧電発振器を、シート状基板母材を使用したバッチ処理によって量産する過程において、シート状基板母材をダイシングブレードによって個片に分割する際に従来発生していた不具合である調整用端子の損傷、脱落という不具合を解消することができる。
請求項１の発明は、調整用端子を、前記絶縁基板の底部であって、前記外部電極と干渉しない位置に配置し、前記絶縁基板を貫通するスルーホールを介して前記ＩＣ部品搭載用パッドと導通させた。このため、シート状絶縁基板母材を個片に切断する際に発生し易い調整用端子の脱落、損傷等という問題を解消することができる。
請求項２の発明では、前記絶縁基板を、底面に外部電極を備えた第１層の絶縁シートと、凹陥部を挟んで対向配置された２つの外壁を形成する第２層の絶縁シートから構成したので薄型化を達成できる。
請求項３の発明は、シート状基板母材を用いてバッチ処理によって個々の工程を実施して行くことにより、歩留まりよく圧電発振器を量産することができる。
請求項４の発明は、大面積のシート状基板母材を用いて、順次ＩＣ部品搭載、樹脂充填、圧電振動子搭載といった工程を順次実施して行くことにより、請求項１及び２に記載の表面実装用圧電発振器を多数連結した構造体を形成することができ、この構造体を個片毎にダイシングすることによって、底面に調整用端子を備えた圧電発振器を歩留まりよく量産することが可能となる。
請求項５の発明は、圧電発振器を構成する絶縁基板側に調整用端子を設ける必要がなくなる分だけ、絶縁基板上に設ける電極、パッド、配線などのレイアウト自由度が高まる。また、廃棄領域上に設ける調整用端子の面積を大きくできるので、プローブピンを当接させることによる調整作業をし易くすることができる
請求項６の発明に係るシート状基板母材によれば、絶縁基板側に調整用端子を設けない場合に、シート状基板母材側に設けた廃棄領域に調整用端子を設けておくことにより、ＩＣ部品の調整作業を含めた製造工程を効率的に行うことが可能となる。
請求項７の発明に係る製造方法によれば、請求項５に記載の圧電発振器を生産性よく量産することができる。
【図面の簡単な説明】
【図１】（ａ）〜（ｄ）は本発明の一実施形態に係る表面実装用電子部品（圧電発振器）の外観斜視図、内部構造を示す縦断面図、要部平面図及び基板の斜視図。
【図２】（ａ）〜（ｄ）はシート状基板母材の構成を示す要部平面図、及び要部縦断面図。
【図３】（ａ）（ｂ）は本発明の他の実施形態に係る表面実装用圧電発振器。
【図４】（ａ）（ｂ）はシート状基板母材を用いて図３の圧電発振器を製造する手順を説明するための要部平面図、及びＷ−Ｗ断面図。
【図５】シート状絶縁基板の他の構成例を示す平面図。
【図６】（ａ）（ｂ）はシート状基板母材の説明図。
【図７】（ａ）〜（ｄ）は従来の表面実装用の圧電発振器の外観斜視図、内部構造を示す縦断面図、ＩＣ部品を搭載した絶縁基板の平面図、及び絶縁基板の斜視図。
【図８】（ａ）（ｂ）は従来のシート状基板母材の要部平面図、及び縦断面図。
【図９】他の従来例に係るシート状基板母材の縦断面図。
【符号の説明】
１　表面実装用圧電発振器、２　ＩＣ部品搭載用パッケージ（ＩＣ部品ユニット）、３　圧電振動子、５　絶縁基板、６　凹陥部、７　ＩＣ部品搭載用パッド、７ａ、７ｂ　配線パターン、８　ＩＣ部品、９　外部電極、９ａ　配線パターン、１０　外壁、１０Ａ　開放部、１１　上部電極、１１ａ　配線パターン、１２　絶縁樹脂、２１　凹陥部、２２　圧電振動素子、２３　蓋、２５　パッド、２６　底面電極、３０　調整用端子、３１　スルーホール（貫通孔）、３２　導体（金属）、３５　シート状基板母材、４０　絶縁基板シート、４１、４２セラミックシート（絶縁シート）、５０　電解メッキ用配線パターン、５１　パッド、５５　接続導体（内部導体）、Ａ　廃棄領域、６０　シート状基板母材、６１廃棄領域、６２　絶縁基板シート、７０　シート状基板母材、７１　調整用端子。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an improvement of a piezoelectric oscillator such as a crystal oscillator, and more particularly, to a surface-mounted piezoelectric oscillator of a type in which a packaged piezoelectric vibrator is fixedly integrated on an IC component unit on which an IC component is mounted, a method of manufacturing the same, and an IC. The present invention relates to a sheet-like substrate base material of a unit for mounting components.
[0002]
[Prior art]
Due to the rapid progress in price reduction and miniaturization accompanying the spread of mobile communication devices such as mobile phones, the price, size and thickness of piezoelectric oscillators such as crystal oscillators used in these communication devices have also been reduced. The demand for conversion is increasing. In response to such demands, not only are crystal oscillators packaged, but also oscillation circuits including frequency adjustment circuits and frequency temperature compensation circuits are integrated and integrated into ICs to reduce the number of components.
FIGS. 7A to 7D are an external perspective view, a vertical sectional view showing an internal structure, a plan view of an insulating substrate on which IC components are mounted, and a perspective view of an insulating substrate of a conventional piezoelectric oscillator for surface mounting. . The piezoelectric oscillator 101 is of a type in which a packaged piezoelectric vibrator 103 is fixed on an IC component mounting package (IC component unit) 102.
The IC mounting package 102 has a concave portion 106 formed at the center of the upper surface of an insulating substrate 105 made of an insulating material such as ceramic, and an IC chip or package (hereinafter, referred to as IC chip or package) , An IC component) 108 and the electrodes of the IC component 108 are fixed on the pads 107 using solder or the like. At least a part of two opposing outer walls of the four outer walls 110 surrounding the recess 106 is an open part 110A that is open.
An external electrode 109 for surface mounting is formed on the bottom surface of the substrate 105, and an upper electrode 111 is formed on the upper surface of the outer wall 110 surrounding the recess 106. The external electrode 109 is connected to the pad 107 or the upper electrode 111 via a connection conductor (not shown). The upper electrode 111 is wired to the pad 107 or the external electrode 109 via a connection conductor (not shown). The IC component 108 mounted in the concave portion 106 may cause a problem such as dew condensation or the like occurring on its electrode or the like due to contact with air, thereby causing a short circuit or the like. Fill (potting) and shut off from outside air.
The piezoelectric vibrator 103 has a configuration in which a piezoelectric vibration element 122 is housed in a concave portion 121 of a box-shaped package body 120 made of ceramic or the like, and the concave portion 121 is hermetically sealed with a lid 123. The piezoelectric vibrating element 122 has an excitation electrode formed on a main surface of a piezoelectric substrate such as a quartz substrate, and a lead electrode extending from the excitation electrode to an edge of the piezoelectric substrate is connected to a pad 125 arranged in the recess 121. On the other hand, a bottom electrode 126 that is electrically connected to the pad 125 is exposed on the bottom of the package body 120 while being fixed. The bottom electrode 126 is connected and fixed to the upper electrode 111 of the IC mounting package 102 in one-to-one correspondence with solder or a conductive adhesive.
[0003]
By the way, in the piezoelectric oscillator having the above configuration, the oscillation frequency and the temperature compensation characteristic are adjusted by writing a required coefficient to a storage area in the IC component 108 mounted on the pad 107 on the inner bottom surface of the recess 106. A side surface of the insulating substrate 105, in particular, an outer surface of the side wall at a position corresponding to the opening 110A is selected as a place where the adjustment terminal 130 is provided. That is, the adjustment terminal 130 has a configuration in which a recess 131 is formed on the outer surface of the side wall, the metal piece 132 is embedded, and the metal piece 132 is further connected to the wiring pattern 107 a extending from each pad 107. By bringing a probe pin or the like extending from the adjustment device into contact with the adjustment terminal 130, it is possible to read, write, rewrite, etc., the set values for various circuits in the IC component 108.
By the way, the above-mentioned piezoelectric oscillator is mass-produced by batch processing using a large-area insulating substrate sheet. FIGS. 8A, 8B, and 8C are a plan view of a main part and a longitudinal sectional view of a main part showing a configuration of a sheet-like substrate base material.
The sheet-shaped substrate base material 135 has a configuration in which a plurality of insulating substrates 105 having the above-described electrode configuration are connected in a sheet shape. The insulating substrate sheet 140 in which the insulating substrates 105 are connected in a sheet shape has a configuration in which three ceramic sheets 141, 142, and 143 are laminated and integrated. External electrodes 109 are formed on the lower surface of the first-layer ceramic sheet 141, and a waste area A between the first-layer and second-layer ceramic sheets 141 and 142 where the insulating substrate 105 does not exist, A wiring pattern 150 used for electrolytic plating is wired, and each plating wiring pattern 150 is connected to a pad 151 for electrolytic plating similarly provided in the disposal area A. The plating wiring pattern 107b extending from each of the IC mounting pads 107 is connected to the wiring pattern 150 located in the immediate vicinity. The pad 151 for electrolytic plating and the wiring pattern 150 for electrolytic plating are used when electrolytically plating gold or copper having good conductivity on the surface of the IC component mounting pad 107.
[0004]
On the other hand, the adjustment terminal 130 connected to each of the IC mounting pads 107 via the wiring pattern 107a is a through-hole (or a through-hole) formed through the edge of the insulating substrate 105 (the edge on the opening 110A side). ) Is formed by embedding a metal piece and then forming break grooves, which will be described later, from the front and back surfaces of the insulating substrate or along the boundary between the insulating substrate and the waste area A in advance.
The third-layer ceramic sheet 143 is laid out so as to form an outer wall 110 for forming the concave portion 106 of each insulating substrate 105, and has an IC component mounting pad 107 on the inner bottom surface of the concave portion 106. An upper electrode 111 is formed on the upper surface of the outer wall 110. The pad 107 and the electrodes 109 and 111 are electrically connected by a connection conductor (inner conductor) 155.
Break grooves 156a and 156b are formed on the upper surface and the lower surface of the insulating substrate sheet 140 along the boundary between the insulating substrates 105 and the boundary between the insulating substrate region and the waste region A, respectively. ing. In the case of using the break using the break groove, the cut surface becomes smoother and burrs are less likely to be formed than in the case of using a dicing blade for cutting. For this reason, there is an advantage that when the metal piece 132 constituting the adjustment terminal 130 is divided, troubles such as the metal piece 132 falling off from the recess 131 are less likely to occur.
The depth of each of the break grooves 156a and 156b is adjusted so as not to cut the wiring pattern 150 for electrolytic plating. In order to fold the insulating substrate cleanly without burrs, the upper break groove 156a needs to have a depth reaching from the third layer to the second layer ceramic sheet as shown in the figure. On the other hand, the lower break groove 156b formed on the lower surface of the first layer ceramic sheet 141 is set to a depth that does not break the wiring pattern 150.
However, in such an insulating substrate sheet 140 having a three-layer structure, the thickness of the insulating substrate sheet is increased by the thickness of the ceramic sheet 141 of the first layer, and the height of the completed piezoelectric oscillator is increased. Having.
In order to solve such a problem and promote thinning of the piezoelectric oscillator, recently, as shown in FIG. 9, a sheet-like substrate base material 135 provided with an insulating substrate sheet having a two-layer structure is used.
[0005]
The insulating substrate sheet 140 having the two-layer structure has a configuration in which two ceramic sheets 141 and 142 are stacked. External electrodes 109 are formed on the lower surface of the first-layer ceramic sheet 141, and a waste area A between the first-layer and second-layer ceramic sheets 141 and 142 where the insulating substrate 105 does not exist (FIG. 8). In (b), a wiring pattern 150 used for electrolytic plating is wired, and each plating wiring pattern 150 is connected to a pad 151 for electrolytic plating provided in the waste area A similarly. The plating wiring pattern 107b extending from each of the IC mounting pads 107 is connected to a plating wiring pattern 150 located in the immediate vicinity. The pads 151 for electrolytic plating and the wiring patterns 150 for electrolytic plating are used when electrolytically plating gold or copper with good conductivity on the surfaces of the IC component mounting pads 107 and the electrodes 109 and 111.
The second-layer ceramic sheet 142 is laid out so as to form an outer wall 110 for forming the recess 106 of each insulating substrate 105, and has an IC component mounting pad 107 on the inner bottom surface of the recess 106, An upper electrode 111 is formed on the upper surface of the outer wall 110. Each of the electrodes 109, 110, and 111 is electrically wired by a connection conductor (inner conductor) 155.
[0006]
If a break groove for folding is formed in the sheet-like base material 135 having a two-layer structure having such a configuration, as shown in FIG. It is necessary to form break grooves 156a and 156b on the upper surface and the lower surface of the sheet-like base material along the boundary with the region A, respectively. However, in order to prevent burrs or the like from being generated on the divided surface, it is necessary to form one of the break grooves deeper than the joining surface of the two ceramic sheets, which results in cutting the wiring pattern 150 for plating. Become. For this reason, a break groove for splitting could not be formed in the sheet-like base material 135 having a two-layer structure, and only a cutting method using a dicing blade could be adopted.
However, in the case of cutting with a dicing blade, burrs are likely to be generated on the cut surface, and in particular, it is difficult to smoothly cut a metal piece embedded in the through hole to form the adjustment terminal 130. However, such problems as deformation and detachment of metal pieces have been brought about.
In other words, when a sheet-like substrate base material 135 employing a two-layer insulating substrate sheet 140 is used in order to reduce the thickness of the insulating substrate, a break groove for dividing between the substrates cannot be employed. In the case of division by dicing, there has been a problem that burrs formed on the cut surface result in defective formation of the adjustment terminals, thereby increasing the defective product occurrence rate.
Furthermore, the provision of the adjustment terminals on the outer surface of the insulating substrate constituting the piezoelectric oscillator itself has resulted in the miniaturization of the oscillator and the hindrance of the freedom of layout. That is, if the plane area and height of the insulating substrate are limited to reduce the size of the oscillator, it is difficult to secure a space for arranging the adjustment terminals. As a result, the degree of freedom in designing the layout and wiring of the wiring patterns is greatly restricted.
[0007]
[Problems to be solved by the invention]
The present invention has been made in view of the above, and has been made in consideration of a piezoelectric oscillator including an IC component unit having an IC component mounted on an insulating substrate, and a packaged piezoelectric vibrator fixed on the IC component unit. In the process of mass production by batch processing using a sheet-shaped substrate base material, there is a problem that the adjusting terminals are damaged or dropped, which is a problem that has conventionally occurred when the sheet-shaped substrate base material is divided into individual pieces by a dicing blade. It is an object of the present invention to provide a surface-mount type piezoelectric oscillator capable of solving the problem, a method of manufacturing the same, and a sheet-like substrate base material.
In particular, when the insulating substrate sheet has a two-layer structure in order to reduce the thickness of the piezoelectric oscillator, a break groove for splitting cannot be formed because it is necessary to avoid breaking of the wiring pattern for plating to be wired between the layers. When cutting between substrates, a dicing blade must be used, but when cutting with a dicing blade, burrs occur on the cut surface between the insulating substrates, and there is a metal piece constituting the adjustment terminal on the cut surface In such a case, the metal pieces may be damaged or fall off, and the yield rate may be reduced. However, in the present invention, such a conventional problem is solved by providing the adjustment terminal at a position avoiding the end face of the insulating substrate. can do.
Another object of the present invention is to provide a conventional layout of the adjustment terminals on the outer surface of the insulating substrate constituting the piezoelectric oscillator. Solving the problem.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, an invention according to claim 1 is an insulating substrate having a concave portion for mounting an IC component having two open side walls on one surface, and an IC substrate for mounting an IC component formed on an inner bottom surface of the concave portion. A pad, an adjustment terminal connected to the IC component mounting pad, an upper electrode disposed on the upper two outer walls opposed to each other with the concave portion interposed therebetween, and an external electrode for surface mounting exposed on the outer bottom of the insulating substrate An IC component unit comprising: a connection conductor for wiring the IC component mounting pad, an upper electrode, and an external electrode; and a resin filled in the recess to cover the IC component. A piezoelectric vibrator including a package having a bottom electrode connected to the upper electrode when mounted on an upper surface, and a piezoelectric vibrating element hermetically housed in the package; Terminal The a bottom portion of the insulating substrate, the disposed in a position that does not interfere with the external electrodes, characterized in that it via a through-hole conductive with the IC component mounting pad for penetrating the insulating substrate.
The adjustment terminals drawn out from the IC component mounting pads connected to the IC component side electrodes are used for testing the operation state of the IC components and adjusting the characteristic values. If it is provided on the side surface of the insulating substrate, it causes various problems in the manufacturing process by batch processing. Therefore, in the present invention, by providing the adjustment terminals on the back surface of the insulating substrate, the problem of dropping or damage of the adjustment terminals, which easily occurs when the sheet-like insulating substrate base material is cut into pieces, has been solved.
The invention according to claim 2 is characterized in that the insulating substrate has a configuration in which two insulating sheets are stacked.
The thickness can be reduced by forming the insulating substrate from a first-layer insulating sheet having an external electrode on the bottom surface and a second-layer insulating sheet forming two outer walls opposed to each other with the concave portion interposed therebetween.
[0009]
According to a third aspect of the present invention, there is provided an insulating substrate sheet in which a plurality of insulating substrates each having an IC component mounting concave portion having two open side walls facing each other are connected in a sheet shape; An IC component mounting pad formed on the inner bottom surface, an adjustment terminal connected to each of the IC component mounting pads, and an upper electrode disposed on the upper portion of two outer walls opposed to each other with the recesses interposed therebetween; A sheet-like substrate base material including surface mounting external electrodes formed on each outer bottom of the insulating substrate, and connection conductors for wiring the IC component mounting pads, the upper electrodes, and the external electrodes. Wherein the sheet-like substrate base material is formed by laminating a second insulating sheet constituting the outer wall on a first insulating sheet having the external electrodes on the bottom and the IC mounting pads on the upper surface. With an integrated configuration On the discarded area of the first insulating sheet, there is formed an electrolytic plating pattern that is electrically connected to each of the IC mounting pads, the upper electrode, and the external electrode, and the discarded area of the second insulating sheet. An electroplating pad connected to the electroplating pattern is formed on the top, and each of the adjustment terminals is disposed at a position on the bottom of the first insulating sheet that does not interfere with each of the external electrodes. It is characterized by being electrically connected to each of the IC component mounting pads via a through hole penetrating the first insulating sheet.
When a sheet-like substrate base material having such a configuration is used, a piezoelectric oscillator can be mass-produced with high yield by performing individual steps by batch processing.
According to a fourth aspect of the present invention, there is provided a method of manufacturing the surface mount type piezoelectric oscillator according to the first or second aspect using the sheet-like substrate preform according to the third aspect, wherein the sheet-like substrate preform is electrolyzed. A step of electroplating a metal on the IC component mounting pad, the upper electrode, and the external electrode, respectively, by immersing in a liquid and supplying an electric current from the electrolytic plating pad; and forming the sheet-shaped substrate base material. A step of mounting the IC component on the IC component mounting pad of each insulating substrate; a step of filling the concave portion with a resin to cover the IC component with a resin; and a step of mounting the IC package on the upper electrode of each insulating substrate. A step of mounting the piezoelectric vibrator by connecting the bottom electrodes, and a step of dicing the sheet-like substrate preform after each step into individual pieces of a piezoelectric oscillator by dicing, and separating the discarded area. Characterized by comprising a and.
3. A large number of surface-mounting piezoelectric oscillators according to claim 1 and 2, by sequentially performing processes such as mounting of IC components, resin filling, and mounting of a piezoelectric vibrator using a large-area sheet-shaped base material. A connected structure can be formed, and by dicing this structure into individual pieces, it becomes possible to mass-produce a piezoelectric oscillator having an adjustment terminal on the bottom surface with a high yield.
[0010]
A surface-mount type piezoelectric oscillator according to a fifth aspect of the present invention is an insulating substrate having a concave portion for mounting an IC component having two open side walls on one side, and an IC component mounting formed on an inner bottom surface of the concave portion. A pad, a connection conductor for connecting the IC component mounting pad and the adjustment terminal, an upper electrode disposed on two upper outer walls opposed to each other with the concave portion interposed therebetween, and a surface mount exposed on the outer bottom of the insulating substrate An external electrode for connection, a connection conductor for wiring the IC component mounting pad, the upper electrode, and the external electrode, and a resin filled in the recess to cover the IC component. A piezoelectric vibrator including a package having a bottom electrode connected to the upper electrode when mounted on the upper surface of the IC component unit, and a piezoelectric vibrating element hermetically housed in the package. And Serial insulating substrate is characterized in that the adjustment pin is not disposed.
The adjustment terminals are not provided on the insulating substrate itself, but are provided in the disposal area where they are finally disposed in the manufacturing process using the sheet-like substrate base material. After the process is completed, an adjustment operation is performed using an adjustment terminal provided on a disposal area arranged adjacent to each piece, and when the individual pieces are divided after the adjustment is completed, the disposal area is discarded. Therefore, the degree of freedom in layout of electrodes, pads, wiring, and the like provided on the insulating substrate is increased by the necessity of providing the adjustment terminal on the insulating substrate side constituting the piezoelectric oscillator. In addition, since the area of the adjustment terminal provided on the discard area can be increased, the adjustment operation by bringing the probe pins into contact can be easily performed.
[0011]
The sheet-like substrate preform according to the invention of claim 6 is an insulating substrate sheet in which a plurality of insulating substrates each having an IC component mounting recessed portion having two opposing side walls opened on one surface are connected in a sheet shape; An IC component mounting pad formed on the inner bottom surface of each recess of the insulating substrate, an adjustment terminal connected to each of the IC component mounting pads via a connection conductor, and opposed to each other across the recess. The upper electrodes disposed on the upper two outer walls, the surface mounting external electrodes formed on the outer bottoms of the insulating substrates, the IC component mounting pads, the upper electrodes, and the external electrodes are wired. A connection substrate, and a sheet-like substrate preform comprising: the sheet-like substrate preform having a waste area for closing at least one of the two open portions of the concave portion of each insulating substrate, Place the adjustment terminals on each of the disposal areas It is characterized by the location.
According to this invention, as described in claim 5, when the adjustment terminal is not provided on the insulating substrate side, by providing the adjustment terminal in a disposal area provided on the sheet-like substrate base material side, It is possible to efficiently perform a manufacturing process including an IC component adjusting operation. Further, since the opening of the recess is closed by the waste area, there is no danger of the resin flowing out during filling of the resin. By arranging the adjustment terminals connected to the IC mounting pads on each of the insulating substrates located on both sides thereof on one waste area, the number of waste areas is reduced, and the sheet-like substrate base material is reduced. It can be used effectively with less waste.
According to a seventh aspect of the present invention, there is provided a method of manufacturing the surface mount type piezoelectric oscillator according to the fifth aspect using the sheet-like substrate preform according to the sixth aspect, wherein the sheet-type substrate preform is provided. Mounting the IC component on the IC component mounting pad of each insulating substrate, filling the concave portion with a resin and coating the IC component with a resin, and on the upper electrode of each insulating substrate, Mounting the piezoelectric vibrator by connecting the bottom electrodes of the respective packages, and dividing the sheet-like substrate base material after the respective steps into individual pieces of a piezoelectric oscillator by dicing, and reducing the waste area. A method of manufacturing a surface-mount type piezoelectric oscillator, comprising a step of separating.
According to this, the piezoelectric oscillator according to claim 5 can be mass-produced with high productivity.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
1 (a), 1 (b), 1 (c) and 1 (d) are an external perspective view, a longitudinal sectional view showing an internal structure, and a plan view of a main part of a surface mount electronic component (piezoelectric oscillator) according to an embodiment of the present invention. And a perspective view of an insulating substrate.
The surface mounted piezoelectric oscillator 1 is of a type in which a packaged piezoelectric vibrator 3 is fixed on an IC component mounting package (IC component unit) 2.
The IC mounting package 2 has a groove-shaped recess 6 formed at the center of the upper surface of an insulating substrate 5 made of an insulating material such as ceramic, and an IC chip or package is mounted on an IC component mounting pad 7 provided on the inner bottom surface of the recess. (Hereinafter referred to as an IC component) 8 is mounted, and electrodes of the IC component 8 are fixed on the IC component mounting pads 7 using solder or the like. At least a part of two opposing outer walls of the four outer walls 10 surrounding the recess 6 is an open portion 10A that is open.
An external electrode 9 for surface mounting is formed on the bottom surface of the insulating substrate 5, and an upper electrode 11 is formed on the upper surface of two outer walls 10 opposed to each other with the recess 6 interposed therebetween. The external electrode 9 is connected to the IC mounting pad 7 or the upper electrode 11 via a connection conductor (not shown). The upper electrode 11 is wired to the IC mounting pad 7 or the external electrode 9 via a connection conductor (not shown). The IC component 8 mounted in the concave portion 6 may cause a problem such as dew condensation or the like occurring on its electrodes or the like due to contact with air, thereby causing a short circuit or the like. Fill (potting) and shut off from outside air. The insulating resin 12 is filled in the recess 6 so as to cover the entire outer surface of the IC component 8 in a state of being melted by an injector or the like, and then cured.
The piezoelectric vibrator 3 has a configuration in which a piezoelectric vibration element 22 is housed in a concave portion 21 of a box-shaped package body 20 made of ceramic or the like, and the concave portion 21 is hermetically sealed with a lid 23. The piezoelectric vibrating element 22 has an excitation electrode formed on a main surface of a piezoelectric substrate such as a quartz substrate, and a lead electrode extending from the excitation electrode to an edge of the piezoelectric substrate is connected to a pad 25 arranged in the recess 21. On the other hand, a bottom surface electrode 26 that is electrically connected to the pad 25 is exposed on the bottom surface of the package body 20 while being fixed. The bottom electrode 26 is connected and fixed to the upper electrode 11 of the IC mounting package 2 in one-to-one correspondence with solder or a conductive adhesive.
[0013]
By the way, in the piezoelectric oscillator of the present invention having the above-described configuration, the required oscillation coefficient is written in the storage area in the IC component 8 mounted on the IC mounting pad 7 on the inner bottom surface of the recess 6 so as to obtain the oscillation frequency. (The input terminal or the test terminal) 30 for adjusting the temperature and the temperature compensation characteristic is selected as the place where the rear face of the insulating substrate 5, particularly the back face at the position facing the inner bottom face of the concave portion is selected. .
That is, the adjustment terminal 30 has a configuration in which a conductor (metal) 32 is filled in a through-hole (or through-hole) 31 formed through the wiring pattern 7 a extending from each pad 7. The rear side portion is an adjustment terminal 30. By bringing a probe pin or the like extending from the adjustment device into contact with the adjustment terminal 30, reading, writing, rewriting, and the like of the set value for various circuits in the IC component 8 can be performed.
As described above, the characteristic configuration of the piezoelectric oscillator of the present invention is that the adjustment terminal 30 extending from the IC component mounting pad 7 provided on the inner bottom surface of the concave portion of the IC component mounting insulating substrate 5 is provided on the back surface of the insulating substrate 5. And is arranged to be exposed at a position that does not interfere with the external electrode 9.
For this reason, even if the piezoelectric oscillator is cut into pieces using a dicing blade when the piezoelectric oscillator is divided into pieces in the manufacture of the piezoelectric oscillator pieces by batch processing using a sheet-shaped substrate base material, the adjustment terminals 30 Is located on the back surface of the insulating substrate, there is no risk of being affected by burrs or the like formed on the cut surface during dicing.
Although the IC component mounting package 2 shown in FIG. 1 shows an example in which the concave portion 6 is formed on the upper surface of the insulating substrate, the concave portion 6 is provided on the lower surface of the insulating substrate, and the concave portion 6 is opposed to the concave portion 6. An external electrode is provided on the lower surface of the two outer walls and an upper electrode is provided on the upper surface. After mounting the IC component in the recessed portion 6, the resin is filled, and then the piezoelectric substrate is provided on the upper surface of the insulating substrate provided with the upper electrode. A vibrator may be mounted.
The following embodiments will be described mainly with respect to an example in which a concave portion is provided on the upper surface side of the insulating substrate as shown in FIG.
[0014]
Next, the piezoelectric oscillator as described above is mass-produced by batch processing using a large-area sheet-shaped substrate base material. 2 (a), 2 (b), 2 (c) and 2 (d) are a plan view of a main part and a longitudinal sectional view of a main part showing the structure of a sheet-like substrate base material.
The sheet-shaped substrate base material 35 has a configuration in which a plurality of insulating substrates 5 having the above-described electrode configuration are connected in a sheet shape. That is, the sheet-shaped substrate base material 35 is formed by laminating and integrating two ceramic sheets (insulating sheets) 41 and 42 on an insulating substrate sheet 40 as described above, the pads 7, the electrodes 9, 11 and the wiring patterns 7a and 7b, 9a, 11a and the like are formed. External electrodes 9 are formed on the lower surface of the first-layer ceramic sheet 41, and in the disposal area A between the first-layer and second-layer ceramic sheets 41 and 42 where the insulating substrate 5 does not exist, A wiring pattern 50 used for electrolytic plating is wired, and each wiring pattern 50 for plating is connected to a pad 51 for electrolytic plating provided on the disposal area A of the ceramic sheet 42 of the second layer. The wiring patterns 7b, 9a, 11a for plating extending from the respective pads 7, the external electrodes 9, and the upper electrode 11 for mounting the IC are connected to the wiring patterns 50 located in the immediate vicinity, respectively. The pad 51 for electrolytic plating and the wiring pattern 50 for electrolytic plating are used when electrolytically plating gold or copper with good conductivity on the surfaces of the IC component mounting pad 7 and the electrodes 9 and 11.
On the other hand, the adjustment terminal 30 connected to each of the IC mounting pads 7 via the wiring pattern 7a is provided with a metal piece 32 in a through hole (or a through hole) 31 formed through the insulating substrate 5 at an appropriate position in the concave portion. Is formed by embedding. Then, adjustment, measurement, and the like are performed by bringing a probe pin into contact with the bottom of the metal piece 32 in the through hole 31.
[0015]
The second-layer ceramic sheet 42 is laid out so as to form two outer walls 10 that form the recess 6 of each insulating substrate 5, and has IC component mounting pads 7 on the inner bottom surface of the recess 6, An upper electrode 11 is formed on the upper surface of the outer wall 10. The pad 7 and each of the electrodes 9 and 11 are electrically connected by a connection conductor (inner conductor) 55.
After mounting the IC components 8 on the respective IC mounting pads 7 of the respective insulating substrates 5 constituting the sheet-like substrate base material 35 having such a configuration, the resin 12 is filled therein. Is fixed to the piezoelectric vibrator 3.
Thereafter, the sheet-like substrate base material 35 on which the piezoelectric vibrator 3 is mounted is cut along the boundary between the individual pieces, thereby obtaining the individual piezoelectric oscillator pieces.
No special grooves or the like are formed on the upper and lower surfaces of the insulating substrate sheet along the boundary between the insulating substrates 5 and the boundary between the insulating substrate region and the waste region A. Is cut along a path (cutting line L) along the boundary line by a dicing machine provided with. In the case of dicing, burrs may be generated on the cut surface. However, the sheet-like substrate base material 35 of the present embodiment has no adjustment terminals or the like at the boundary between the insulating substrates 5, so that the cut surface Even if burrs are generated, there is little possibility that electrical characteristics will be affected.
By setting the waste area A on the opening 10A side of the recess 6 at the same height as the outer wall 10, when the resin 12 is filled in the recess, the waste area A prevents the resin from flowing out. Will function as
[0016]
Next, a method for manufacturing a piezoelectric oscillator using the sheet-like substrate base material 35 includes the following steps.
That is, first, the sheet-like substrate base material 35 having the configuration as shown in FIG. 1 is immersed in the electrolytic solution and energized from the electrolytic plating pad 51, so that the IC component mounting pad 7 and each electrode 9 , 11 are electrolytically plated with a highly conductive metal. These pads and electrodes are made of tungsten or the like in advance, and themselves are not well-adapted to solder. Therefore, a film of gold, copper, or the like is formed through nickel or the like.
Next, a step of mounting the IC component 8 on the IC component mounting pad 7 of each insulating substrate 5 constituting the sheet-like substrate base material 35 is performed. Cream solder is applied to the IC component mounting pad 7 in advance using a predetermined mask, and the IC component 8 is mounted by reflow.
Next, the concave portion 6 is filled with the molten resin 12 to cover the IC component 8, and then the bottom electrode 26 of each piezoelectric vibrator 3 is connected by soldering to the upper electrode 11 of each insulating substrate 5. The piezoelectric vibrator 3 is mounted.
Finally, a step of dividing the sheet-like substrate base material 35 having passed through each step into individual pieces of the piezoelectric oscillator by dicing and separating the disposal area A is performed.
By performing the steps as described above, it becomes possible to manufacture the surface-mounting piezoelectric oscillator having the configuration shown in FIG. 1 with high productivity.
[0017]
Next, FIG. 3 shows a surface-mounting piezoelectric oscillator according to another embodiment of the present invention. The same parts as those in the embodiment of FIG. 5 is characterized in that there is no adjustment terminal on the outer surface.
That is, the surface-mounting piezoelectric oscillator 1 is of a type in which a piezoelectric vibrator 3 packaged on an IC component mounting package (IC component unit) 2 is fixed.
The IC mounting package 2 has a groove-shaped recess 6 formed at the center of the upper surface of an insulating substrate 5 made of an insulating material such as ceramic, and an IC chip or package is mounted on an IC component mounting pad 7 provided on the inner bottom surface of the recess. (Hereinafter referred to as an IC component) 8 is mounted, and electrodes of the IC component 8 are fixed on the IC component mounting pads 7 using solder or the like. At least a part of two opposing outer walls of the four outer walls 10 surrounding the recess 6 is an open portion 10A that is open.
An external electrode 9 for surface mounting is formed on the bottom surface of the insulating substrate 5, and an upper electrode 11 is formed on the upper surface of two outer walls 10 opposed to each other with the recess 6 interposed therebetween. The external electrode 9 is connected to the IC mounting pad 7 and the upper electrode 11 via a connection conductor (not shown). The upper electrode 11 is connected to the IC mounting pad 7 and the external electrode 9 via a connection conductor (not shown). The IC component 8 mounted in the concave portion 6 may cause a problem such as dew condensation or the like occurring on its electrodes or the like due to contact with air, thereby causing a short circuit or the like. Fill (potting) and shut off from outside air. The insulating resin 12 is filled in the recess 6 so as to cover the entire outer surface of the IC component 8 in a state of being melted by an injector or the like, and then cured.
The configuration of the piezoelectric vibrator 3 is the same as that of the embodiment of FIG.
[0018]
By the way, the characteristic configuration of the piezoelectric oscillator of the present invention having the above configuration is that no adjustment terminal is arranged on any part of the insulating substrate 5. That is, the oscillation frequency and the temperature compensation characteristic are usually adjusted by writing a required coefficient to the storage area in the IC component 8 mounted on the IC mounting pad 7 on the inner bottom surface of the recess 6 in the piezoelectric oscillator. Terminals (input terminals or test terminals) for the adjustment are provided on the outer peripheral surface. In this type of piezoelectric oscillator, adjustment work is performed by contacting a probe pin with an adjustment terminal provided on each completed piezoelectric oscillator. On the other hand, in the piezoelectric oscillator according to the present embodiment, the piezoelectric oscillator itself is not provided with an adjustment terminal as described later, and a sheet-like substrate base material used when the piezoelectric oscillator is produced by batch processing. Adjustment terminals are provided only on the discard area, and the adjustment terminals on the discard area located immediately adjacent to each insulating substrate are electrically connected to the IC component mounting pads on the individual insulating boards. After the assembly of the IC components on the sheet-shaped substrate base material, the filling of the resin, the mounting of the piezoelectric vibrator, and the like, the adjustment work using the adjustment terminals on the disposal area is completed before dividing into individual pieces. Keep it.
[0019]
Next, FIGS. 4A and 4B are plan views of essential parts for explaining a procedure for manufacturing the piezoelectric oscillator of FIG. 3 using a sheet-like substrate base material (IC parts by removing a part of the resin). Are exposed) and WW sectional views.
The sheet-shaped substrate preform 60 is configured such that a plurality of insulating substrates 5 having the above-described electrode configuration are connected in a sheet shape, and a disposal area 61 is arranged at an appropriate position along an edge of the insulating substrate 5. It has. The sheet-like substrate base material 60 has a configuration in which the pads 7, the electrodes 9, 11 and the like are formed on an insulating substrate sheet 62 obtained by laminating and integrating a plurality of ceramic sheets (insulating sheets).
That is, the two sets of insulating substrates 5 are arranged laterally adjacent to each other so that the recesses 6 communicate with each other, and the narrow band-shaped waste areas 61 are closely attached along the outer edges of the two insulating substrates 5. By arranging, the outside of the recessed portions of both insulating substrates 5 is closed by the waste area 61. A plurality of such two insulating substrates 5 are continuously provided in the vertical and horizontal directions to form one sheet-like substrate preform 60.
An IC component mounting pad 7 is formed on the inner bottom surface of the concave portion 6 of each insulating substrate 5, an external electrode 9 is formed on the lower surface thereof, and an upper electrode 11 is formed on an upper portion of the outer wall 10. . The pad 7, the external electrode 9, and the upper electrode 11 are electrically connected via a connection conductor.
Since the waste area 61 is arranged so as to close the outer edges of the recesses 6 of the two insulating substrates 5 arranged adjacent to each other, the resin 12 is filled after the IC component 8 is mounted on the pad 7. It functions as a damming means. The adjustment terminal 70 formed on the discarded area 61 is electrically connected to the IC mounting pad 7 in the adjacent recess 6 via the connection conductor 71 in a one-to-one relationship. The adjustment terminal 70 can also be arranged on the lower surface side of the disposal area 61 as necessary. Each adjustment terminal 70 on the discard area 61 is connected to a pad 7 on the insulating substrate located on each of the left and right sides of the discard area 61.
Note that, in the present embodiment, an example is shown in which the two insulating substrates 5 are arranged continuously in the horizontal direction, and the waste areas 61 are arranged along both outer edges, however, this is an example. A waste area may be arranged along both sides of each insulating substrate.
[0020]
After mounting the IC parts 8 on the respective IC mounting pads 7 of the respective insulating substrates 5 constituting the sheet-like substrate base material 60 having such a configuration, the resin 12 is filled. Is fixed to the piezoelectric vibrator 3.
Thereafter, the sheet-like substrate preform 60 on which the piezoelectric vibrator 3 is mounted is cut along the boundaries L between the individual pieces and between the individual pieces and the disposal area, thereby obtaining the piezoelectric oscillator pieces.
In this cutting step, the connection conductor 71 that connects the pad 7 and the adjustment terminal 70 is cut, and the connection terminal 70 does not remain on the insulating substrate 5 side.
The measurement and adjustment of the set values for the various circuits in the IC component 8 mounted on each of the insulating substrates 5 is performed by bringing the probe pins of the adjustment device into contact with the adjustment terminals 70 in a state before the division. It is implemented by having
In this embodiment, since the adjustment terminals are provided on the disposal region 61 which is a region separate from the insulating substrate, a large area for each adjustment terminal can be secured, and the adjustment operation using the probe pins can be performed. Accurate and easy.
FIG. 5 is a plan view showing another example of the configuration of the sheet-like insulating substrate. The difference between the sheet-like insulating substrate according to this embodiment and the embodiment of FIG. Instead of being disposed on the side, they are arranged outside each outer wall 10, and are arranged laterally adjacent without interposing the waste area 61 between the insulating substrates.
As shown in FIGS. 6A and 6B, the adjustment terminals 70 are arranged on the upper surface and / or the lower surface of the discard region 61, and are connected to the IC mounting pads 7 in the recesses via the connection conductors 71. The point that the piezoelectric vibrator 3 is mounted and cut along the boundary line L with the insulating substrate after the adjustment work is completed, and the disposal area 61 is discarded is the same as in the above embodiment.
[0021]
【The invention's effect】
As described above, according to the present invention, in the process of mass-producing a piezoelectric oscillator by batch processing using a sheet-shaped substrate base material, a conventional problem occurs when the sheet-shaped substrate base material is divided into individual pieces by a dicing blade. It is possible to solve the problem that the adjustment terminal is damaged or dropped, which is a problem.
The invention according to claim 1, wherein the adjusting terminal is disposed at a position on the bottom of the insulating substrate that does not interfere with the external electrode, and the IC component mounting pad is connected to the pad through a through hole penetrating the insulating substrate. Conducted. For this reason, it is possible to solve the problem that the adjustment terminals are easily dropped or damaged when the sheet-like insulating substrate base material is cut into pieces.
According to the second aspect of the present invention, the insulating substrate includes a first-layer insulating sheet having an external electrode on a bottom surface and a second-layer insulating sheet forming two outer walls opposed to each other with a recessed portion interposed therebetween. As a result, the thickness can be reduced.
According to the third aspect of the invention, the individual steps are performed by batch processing using the sheet-like substrate base material, so that the piezoelectric oscillator can be mass-produced with high yield.
According to a fourth aspect of the present invention, steps of sequentially mounting IC components, filling a resin, and mounting a piezoelectric vibrator are sequentially performed using a large-area sheet-shaped base material. It is possible to form a structure in which many surface-mounting piezoelectric oscillators are connected, and by dicing this structure into individual pieces, it is possible to mass-produce piezoelectric oscillators with adjustment terminals on the bottom surface with high yield. Become.
According to the fifth aspect of the present invention, the degree of freedom in layout of electrodes, pads, wiring, and the like provided on the insulating substrate is increased by the necessity of providing the adjustment terminal on the insulating substrate side constituting the piezoelectric oscillator. Further, since the area of the adjustment terminal provided on the discarded area can be increased, the adjustment work by bringing the probe pins into contact can be facilitated.
According to the sheet-like substrate base material of the invention of claim 6, when the adjustment terminals are not provided on the insulating substrate side, by providing the adjustment terminals in the disposal area provided on the sheet-like substrate base material side, In addition, it is possible to efficiently perform a manufacturing process including an IC component adjusting operation.
According to the manufacturing method of the seventh aspect, the piezoelectric oscillator according to the fifth aspect can be mass-produced with high productivity.
[Brief description of the drawings]
FIGS. 1A to 1D are external perspective views, a longitudinal sectional view showing an internal structure, a main part plan view, and a perspective view of a substrate of a surface-mounting electronic component (piezoelectric oscillator) according to an embodiment of the present invention. FIG.
FIGS. 2A to 2D are a main part plan view and a main part longitudinal sectional view showing the configuration of a sheet-like substrate base material.
3 (a) and 3 (b) are surface mount piezoelectric oscillators according to another embodiment of the present invention.
FIGS. 4A and 4B are a plan view and a cross-sectional view taken along line WW for explaining a procedure for manufacturing the piezoelectric oscillator of FIG. 3 using a sheet-like substrate base material.
FIG. 5 is a plan view showing another configuration example of the sheet-shaped insulating substrate.
FIGS. 6A and 6B are explanatory diagrams of a sheet-like substrate base material.
FIGS. 7A to 7D are external perspective views, a vertical cross-sectional view showing an internal structure, a plan view of an insulating substrate on which IC components are mounted, and a perspective view of an insulating substrate of a conventional piezoelectric oscillator for surface mounting. .
8A and 8B are a plan view and a longitudinal sectional view of a main part of a conventional sheet-like substrate base material.
FIG. 9 is a longitudinal sectional view of a sheet-like substrate base material according to another conventional example.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 surface mount piezoelectric oscillator, 2 IC component mounting package (IC component unit), 3 piezoelectric vibrator, 5 insulating substrate, 6 recess, 7 IC component mounting pad, 7 a, 7 b wiring pattern, 8 IC component, 9 External electrode, 9a wiring pattern, 10 outer wall, 10A open portion, 11 upper electrode, 11a wiring pattern, 12 insulating resin, 21 concave portion, 22 piezoelectric vibrating element, 23 lid, 25 pad, 26 bottom electrode, 30 adjusting terminal, 31 through hole (through hole), 32 conductor (metal), 35 sheet substrate base material, 40 insulating substrate sheet, 41, 42 ceramic sheet (insulating sheet), 50 wiring pattern for electrolytic plating, 51 pad, 55 connection conductor ( Internal conductor), A discarded area, 60 sheet substrate preform, 61 discarded area, 62 insulating substrate sheet, 70 sheet substrate preform, 71 tone Use terminal.

Claims

An insulating substrate having a concave portion for mounting an IC component having two open side walls open on one side, an IC component mounting pad formed on the inner bottom surface of the concave portion, and an adjusting device connected to the IC component mounting pad A terminal, an upper electrode disposed on upper portions of two outer walls opposed to each other with the concave portion interposed therebetween, an external electrode for surface mounting exposed and formed on an outer bottom portion of the insulating substrate, a pad for mounting IC components, an upper electrode, and an external electrode. An IC component unit comprising: a connection conductor for wiring; and a resin filled in the concave portion to cover the IC component.
A piezoelectric vibrator including a package having a bottom electrode connected to the upper electrode when mounted on the upper surface of the IC component unit, and a piezoelectric vibrating element hermetically housed in the package. And
The adjusting terminal is disposed at a position that does not interfere with the external electrode at the bottom of the insulating substrate, and is electrically connected to the IC component mounting pad via a through hole that penetrates the insulating substrate. Characteristic surface mount type piezoelectric oscillator.

The surface mount type piezoelectric oscillator according to claim 1, wherein the insulating substrate has a configuration in which two insulating sheets are stacked.

An insulating substrate sheet in which a plurality of insulating substrates each having an IC component mounting concave portion having two open side walls opened on one surface are connected in a sheet shape; and an IC component formed on the inner bottom surface of each concave portion of each of the insulating substrates. A mounting pad, an adjusting terminal connected to each of the IC component mounting pads, an upper electrode disposed on two outer walls opposed to each other with the concave portion interposed therebetween, and an outer electrode of each of the insulating substrates. An external electrode for surface mounting formed on the bottom, a connection conductor for wiring each of the IC component mounting pads, each of the upper electrodes and each of the external electrodes, and a sheet-like substrate base material comprising:
The sheet-like substrate base material has a structure in which a second insulating sheet constituting the outer wall is laminated and integrated on a first insulating sheet having the external electrodes on the bottom and the IC mounting pads on the upper surface. And a pattern for electrolytic plating that is electrically connected to each of the IC mounting pads, the upper electrode, and the external electrode is formed on the discarded area of the first insulating sheet. An electrolytic plating pad connected to the electrolytic plating pattern is formed on the waste area,
Each of the adjustment terminals is located at a bottom portion of the first insulating sheet and does not interfere with each of the external electrodes, and each of the IC components is mounted via a through hole penetrating the first insulating sheet. A sheet-like substrate base material, which is electrically connected to a pad for use.

A method for producing the surface-mounted piezoelectric oscillator according to claim 1 or 2, using the sheet-like substrate base material according to claim 3.
A step of immersing the sheet-like substrate base material in an electrolytic solution and energizing the electrolytic plating pads to electrolytic-plate metals on the IC component mounting pads, upper electrodes, and external electrodes, respectively;
Mounting an IC component on an IC component mounting pad of each insulating substrate constituting the sheet-shaped substrate base material;
A step of filling the inside of the recess with a resin and coating the IC component with a resin;
Mounting the piezoelectric vibrator on the upper electrode of each of the insulating substrates by connecting a bottom electrode of each of the packages;
The step of separating the discarded area while dicing the sheet-like substrate base material after each of the steps into individual pieces of the piezoelectric oscillator by dicing,
A method for manufacturing a surface-mount type piezoelectric oscillator, comprising:

An insulating substrate having a concave portion for mounting an IC component having two open side walls facing each other, an IC component mounting pad formed on the inner bottom surface of the concave portion, the IC component mounting pad and an adjustment terminal; A connecting conductor to be connected, an upper electrode disposed on the upper portion of two outer walls opposed to each other with the concave portion interposed therebetween, an external electrode for surface mounting formed on an outer bottom portion of the insulating substrate, a pad for mounting IC components and an upper electrode An IC component unit comprising: a connection conductor for wiring an external electrode; and a resin filled in the recess to cover the IC component.
A piezoelectric vibrator including a package having a bottom electrode connected to the upper electrode when mounted on the upper surface of the IC component unit, and a piezoelectric vibrating element hermetically housed in the package. And
A surface-mounted piezoelectric oscillator, wherein the adjusting terminal is not arranged on the insulating substrate.

An insulating substrate sheet in which a plurality of insulating substrates each having an IC component mounting concave portion having two open side walls opened on one surface are connected in a sheet shape; and an IC component formed on the inner bottom surface of each concave portion of each of the insulating substrates. A mounting pad, an adjustment terminal connected to each of the IC component mounting pads via a connection conductor, an upper electrode disposed on two outer walls opposed to each other across the recess, and A sheet-like substrate base material comprising: surface mounting external electrodes formed on each outer bottom portion of the insulating substrate; and connection conductors for wiring the IC component mounting pads, the upper electrodes, and the external electrodes. hand,
The sheet-like substrate base material has a discard area for closing at least one of the two open portions of the concave portion of each insulating substrate, and the adjustment terminal is arranged on each discard area. Sheet-like substrate base material.

A method for manufacturing the surface-mounted piezoelectric oscillator according to claim 5, using the sheet-like substrate base material according to claim 6.
Mounting an IC component on an IC component mounting pad of each insulating substrate constituting the sheet-shaped substrate base material;
A step of filling the inside of the recess with a resin and coating the IC component with a resin;
Mounting the piezoelectric vibrator on the upper electrode of each of the insulating substrates by connecting a bottom electrode of each of the packages;
The step of separating the discarded area while dicing the sheet-like substrate base material after each of the steps into individual pieces of the piezoelectric oscillator by dicing,
A method for manufacturing a surface-mount type piezoelectric oscillator, comprising: