JP4356217B2

JP4356217B2 - Electronic component manufacturing method and electronic component

Info

Publication number: JP4356217B2
Application number: JP2000259252A
Authority: JP
Inventors: 義宏小中
Original assignee: Murata Manufacturing Co Ltd
Current assignee: Murata Manufacturing Co Ltd
Priority date: 2000-08-29
Filing date: 2000-08-29
Publication date: 2009-11-04
Anticipated expiration: 2020-08-29
Also published as: JP2002076368A

Abstract

PROBLEM TO BE SOLVED: To electrically reliably connect a functional part with outside to improve the productivity and the reliability. SOLUTION: An upper board 3 having initial through-holes 24 is bonded to a silicon substrate 2. After forming an angular velocity detector 11 on the substrate 2, a lower board 1 is bonded to the substrate 2. A boring process is applied to the initial through-holes 24 by sand blast, etc., to form through- holes 21. A conductive film for electrically connecting the detector 11 to outside is formed on the inner walls of the through-holes 21. This eliminates the shape variation of the through-holes 21, thereby forming through-holes 21 having approximately the same shape.

Description

【０００１】
【発明の属する技術分野】
本発明は、例えば角速度センサ、加速度センサ、メカニカルフィルタ等の電子部品に関し、電気信号を外部に導出する電子部品の製造方法および電子部品に関する。
【０００２】
【従来の技術】
一般に、マイクロマシニング技術を用いてシリコン基板等を加工した電子部品として、角速度センサ、加速度センサ、メカニカルフィルタ等が広く知られている。また、この種の電子部品は、例えばシリコン基板と、該シリコン基板の表面側と裏面側とにそれぞれ面接合されたガラス基板とによって構成されている。そして、シリコン基板には、例えば角速度の検出を行う機能部が設けられ、該機能部は２枚のガラス基板によって封止されている。
【０００３】
また、機能部と外部とを電気的に接続するために、ガラス基板を貫通してシリコン基板に達する貫通穴を形成し、この貫通穴に導電膜を設けたものが知られている（例えば、特開平７−２６３７０９号公報、特開平９−２８３６６３号公報等）。そして、このような従来技術による電子部品は、ガラス基板とシリコン基板とを陽極接合によって接合した後、サンドブラスト加工等を行うことによってガラス基板を貫通してシリコン基板の一部を露出させ、貫通穴を形成する。そして、スパッタ、蒸着等の手段を用いて貫通穴の内壁に導電膜を形成している。
【０００４】
【発明が解決しようとする課題】
ところが、前述した従来技術では、ガラス基板とシリコン基板とを接合した後にガラス基板の表面側から穴加工を施し、ガラス基板からシリコン基板に連通した貫通穴を形成している。そして、このような穴加工は、通常はウエハに多数の電子部品を形成した状態で行われる。
【０００５】
このとき、ウエハ面上でサンドブラスト加工速度にばらつきが生じる傾向があり、ウエハ面のある位置では貫通穴がガラス基板を貫通せずに有底穴となってしまい、またウエハ面の他の位置では貫通穴がシリコン基板をも貫通してしまうことがある。このように、貫通穴がガラス基板を貫通しないときにはシリコン基板の接続部と電気的な接続を行うことができず、一方、貫通穴がシリコン基板をも貫通してしまうときにはシリコン基板の機能部をも損傷する虞がある。このため、電子部品の不良が生じ易く、生産性が低下するという問題がある。
【０００６】
また、電子部品毎に貫通穴の開口面積が異なるため、導電膜と接続部との間のコンタクト抵抗にばらつきが生じる。このため、電子部品の入力抵抗、出力抵抗がばらつくから、機能部の動作特性、検出特性等が電子部品毎に異なるという問題もある。
【０００７】
本発明は上述した従来技術の問題に鑑みなされたもので、機能部と外部とを電気的に確実に接続でき、生産性、信頼性を向上することができる電子部品の製造方法及び電子部品を提供することを目的としている。
【０００８】
【課題を解決するための手段】
上述した課題を解決するために、請求項１の発明は、初期貫通孔を有するガラス基板と機能部を形成する機能部形成基板とを貼り合わせ、前記初期貫通孔を通じて当該初期貫通孔に穴加工を施し、該加工済み貫通孔の内壁に前記機能部と外部との間を電気的に接続する導電膜を設ける構成としてなる電子部品の製造方法であって、前記穴加工では、前記初期貫通孔の内壁を削ることにより、前記ガラス基板のうち前記機能部形成基板と貼り合わされる側の開口端の欠損による突起部を少なくとも除去し、前記ガラス基板と機能部形成基板との間の段差をなくす構成としたことを特徴としている。
【０００９】
このように構成することにより、初期貫通孔を有するガラス基板を機能部形成基板に面接合した後に、初期貫通孔を通じて当該初期貫通孔に穴加工を施すから、初期貫通孔の内壁を研磨してその内径寸法を広げることができ、初期貫通孔に生じる突起等を除去し、ガラス基板と機能部形成基板との間の段差をなくすことができる。このため、加工済み貫通孔の内壁に導電膜を形成することによって、導電膜がガラス基板とシリコン基板との間で断線することがなく、該導電膜によって機能部と外部とを電気的に接続することができる。また、初期貫通孔を穴加工するときには、初期貫通孔の内壁を突起等を除去する程度に僅かに削るだけで済むから、穴加工による加工済み貫通孔の形状ばらつきを少なくすることができる。
【００１０】
また、請求項２の発明は、初期貫通孔を有するガラス基板と機能部を形成する機能部形成基板とを貼り合わせ、前記初期貫通孔を通じて当該初期貫通孔に穴加工を施すと共に前記ガラス基板のうち前記初期貫通孔の周囲に配線用の溝加工を施し、前記ガラス基板の表面と加工済み貫通孔とに全面に亘って導電膜を設け、該導電膜のうちガラス基板の表面の導電膜を除去し、前記加工済み貫通孔と配線用溝との内壁に前記機能部を外部に電気的に接続する導電膜を設ける構成としてなる電子部品の製造方法であって、前記穴加工では、前記初期貫通孔の内壁を削ることにより、前記ガラス基板のうち前記機能部形成基板と貼り合わされる側の開口端の欠損による突起部を少なくとも除去し、前記ガラス基板と機能部形成基板との間の段差をなくし、前記溝加工では、前記ガラス基板に形成された前記初期貫通孔の開口近傍に前記ガラス基板の表面よりも窪んだ前記配線用溝を形成する構成としたことを特徴としている。
【００１１】
これにより、初期貫通孔を有するガラス基板を機能部形成基板に面接合した後に、初期貫通孔を通じて当該初期貫通孔に穴加工を施すから、初期貫通孔の内壁を削ることにより、初期貫通孔の突起等をなくし、ガラス基板と機能部形成基板との間の段差を除去することができる。このため、導電膜がガラス基板とシリコン基板との間で断線することがなく、該導電膜によって機能部と外部とを電気的に接続することができる。
【００１２】
また、貫通孔の穴加工と同時にガラス基板のうち貫通孔の周囲に溝加工を施し、ガラス基板の表面よりも窪んだ配線用溝を形成したから、ガラス基板の表面と加工済み貫通孔とに全面に亘って導電膜を形成することによって、加工済み貫通孔と配線用溝との内壁に導電膜を設けることができる。そして、この状態でガラス基板の表面に研磨処理等を施すことによって、導電膜のうちガラス基板の表面の導電膜を除去し、貫通孔と配線用溝との内壁に機能部と外部とを電気的に接続する導電膜を設けることができる。このため、配線用溝を用いてガラス基板の表面に貫通孔内に接続した配線を形成することができる。
【００１３】
一方、請求項３の発明は、初期貫通孔を有するガラス基板と機能部を形成する機能部形成基板とを貼り合わせ、前記初期貫通孔を通じて当該初期貫通孔に穴加工を施すと共に前記ガラス基板のうち前記初期貫通孔の周囲に配線用の溝加工を施し、前記加工済み貫通孔と配線用溝との内壁に前記機能部を外部に電気的に接続する導電膜を設ける構成としてなる電子部品であって、前記穴加工では、前記初期貫通孔の内壁を削ることにより、前記ガラス基板のうち前記機能部形成基板と貼り合わされる側の開口端の欠損による突起部を少なくとも除去し、前記ガラス基板と機能部形成基板との間の段差をなくし、前記溝加工では、前記ガラス基板に形成された前記貫通孔の開口近傍に前記ガラス基板の表面よりも窪んだ前記配線用溝を形成する構成としたことを特徴としている。
【００１４】
このように構成したことにより、初期貫通孔の内壁を削ることによって初期貫通孔に穴加工を施すから、ガラス基板には加工済み貫通孔を形成することができ、初期貫通孔の突起等を除去し、ガラス基板と機能部形成基板との間の段差をなくすことができる。また、ガラス基板の表面には、初期貫通孔の開口近傍に位置して配線用溝を設けたから、該配線用溝の内壁に加工済み貫通孔の内壁に接続した導電膜を形成することができる。このため、ガラス基板の配線用溝に加工済み貫通孔に接続された配線を取り付けることができる。
【００１５】
また、請求項４の発明は、導電膜のうち配線用溝内に位置した部位を電極パッドとしたことにある。
【００１６】
これにより、電極パッドをなす配線用溝内の導電膜にワイヤーボンディング等を施すことによって、機能部と外部との間を電気的に接続することができる。
【００１７】
【発明の実施の形態】
以下、本発明による実施の形態による電子部品として角速度センサを例に挙げ添付図面に従って詳細に説明する。
【００１８】
まず、図１ないし図１０は本発明の第１の実施の形態を示している。図において、１はガラス基板によって形成された下側基板で、該下側基板１の表面側には、後述するシリコン基板２が陽極接合によって面接合されている。
【００１９】
２は導電性をもった低抵抗の単結晶シリコンによって形成された機能部形成基板としてのシリコン基板で、該シリコン基板２には、エッチング処理を施すことによって、後述の角速度検出部１１、枠部１２が形成されている。
【００２０】
３はガラス基板によって形成された上側基板で、該上側基板３の裏面３Ａは、角速度検出部１１の接続部と枠部１２とに接合するための接合面となり、該上側基板３の裏面３Ａ側の中央には収容凹部３Ｂが形成され、前記裏面３Ａの反対側となる上側基板３の表面３Ｃは非接合面となっている。また、該上側基板３は、角速度検出部１１の接続部と枠部１２とに陽極接合され、下側基板１と上側基板３との間に密閉室４を画成している。
【００２１】
１１は機能部（外力検出部）としての角速度検出部で、該角速度検出部１１は、図２に示すように回転軸Ｘ−Ｘの回りに角速度Ωが作用したとき、この回転軸Ｘ−Ｘ回りの角速度Ωを検出するものである。また、角速度検出部１１は、シリコン基板２をエッチングすることにより、枠部１２の内側に形成されている。
【００２２】
ここで、角速度検出部１１の構成について図２を参照しつつ説明する。１３，１３は下側基板１上に設けられた支持部、１４は凹溝部１５によって下側基板１の表面から離間した状態で設けられ、４本の支持梁１６によって該各支持部１３に支持された振動体をそれぞれ示し、該振動体１４はこれらの支持梁１６によって、図２中の矢示Ａ方向、矢示Ｂ方向に変位可能な状態となっている。また、該振動体１４の両面側にはくし状電極１４Ａ，１４Ａが設けられている。
【００２３】
１７，１７は振動体１４の両側に位置し、下側基板１上に設けられた電極支持部で、該各電極支持部１７の両面側にはくし状電極１７Ａが設けられ、該各くし状電極１７Ａは、振動体１４の各くし状電極１４Ａと離間した状態で噛合している。
【００２４】
１８は振動体１４の下側に位置して下側基板１の表面に設けられた電極板で、該電極板１８は、例えば導電性金属材料によって形成され、振動体１４がコリオリ力により矢示Ｂ方向に変位したときに、その変位量を検出するものである。
【００２５】
１９は電極板１８に接続された引出部で、該引出部１９は、電極板１８から延出され電極板１８と共に下側基板１の表面に設けられた導電性金属材料からなる配線部１９Ａと、該配線部１９Ａの上に設けられたシリコン材料からなるパッド部１９Ｂとによって構成されている。
【００２６】
ここで、支持部１３、電極支持部１７，１７および引出部１９は、角速度検出部１１を電気的に接続する接続部を構成している。
【００２７】
２０，２０，…は上側基板３から角速度検出部１１に亘って形成された４個のビアホール（２個のみ図示）で、該各ビアホール２０は後述する貫通孔２１と、該貫通孔２１の底部に設けられた凹底部２２と、前記貫通孔２１と凹底部２２との内壁に設けられた導電膜２３とにより構成されている。なお、実施の形態では、ビアホール２０は電極支持部１７に設ける場合のみについて図示しているが、支持部１３、引出部１９にも図１と同様にビアホールが穿設されている。
【００２８】
２１，２１，…は上側基板３を貫通して設けられたテーパ状の貫通孔２１で、該各貫通孔２１内には、シリコン基板２のうち接続部をなす各電極支持部１７が露出している。また、各貫通孔２１は、例えば、開口部となる上側基板３の表面３Ｃ側の直径寸法が裏面３Ａ側の直径寸法よりも大きくなっている。このため、貫通孔２１は、上側基板３の表面３Ｃ側からシリコン基板２側に向かって漸次縮径するテーパ状をなしている。
【００２９】
２２，２２，…は貫通孔２１の底部に位置してシリコン基板２に形成された凹底部で、該凹底部２２は貫通孔２１との間に段差なく滑らかに連続した壁面を有し、略円形の浅溝形状をなしている。
【００３０】
２３，２３，…は各貫通孔２１と凹底部２２との内壁に設けられた導電膜で、該導電膜２３は、角速度検出部１１の接続部（支持部１３、各電極支持部１７、引出部１９）から上側基板３の表面３Ｃ側に延びている。また、導電膜２３のうち上側基板３の表面３Ｃ側に位置した部位は、電極パッド２３Ａを構成している。そして、この電極パッド２３Ａに半田バンプ、ワイヤーボンディング等を施すことによって、導電膜２３は角速度検出部１１と外部とを電気的に接続するものである。
【００３１】
このように構成される角速度センサでは、振動体１４のくし状電極１４Ａと電極支持部１７のくし状電極１７Ａとの間には、外部の発振回路から導電膜２３等を通じて駆動信号が印加され、振動体１４を矢示Ａ方向に振動させる。この状態で、角速度センサに回転軸Ｘ−Ｘ回りの角速度Ωが作用すると、振動体１４にコリオリ力が作用し、このコリオリ力の大きさに対応して振動体１４が矢示Ｂ方向に変位し、振動体１４と電極板１８との間の離間距離が変化する。
【００３２】
そして、この離間距離の変化を、振動体１４と電極板１８との間の静電容量による信号とし、この信号を導電膜２３を通じて検出回路に出力する。そして、該検出回路では静電容量を電圧に変換し、回転軸Ｘ−Ｘ回りに加わる角速度Ωを測定することができる。
【００３３】
次に、図３ないし図１１に基づいて、本実施の形態による角速度センサの製造方法について述べる。なお、本実施の形態では単一の角速度センサを製造する場合を例に挙げて説明するが、一枚のシリコン基板２（シリコンウエハ）に多数の角速度センサを製造した後、各角速度センサを切り離す構成としてもよい。
【００３４】
まず、図３は初期貫通孔２４等を形成する前の上側基板３を示している。そして、図４に示す貫通孔加工工程では、上側基板３の裏面側には、角速度検出部１１を収容する収容凹部３Ｂを形成する。また、上側基板３のうち接続部となる支持部１３、各電極支持部１７、引出部１９に接合される部位には、厚さ方向に貫通した初期貫通孔２４を穿設する。このとき、初期貫通孔２４は、上側基板３の表面側からサンドブラスト等の穴あけ加工手段を用いることによって形成する。このため、初期貫通孔２４は表面側から裏面側に向けて漸次縮径した形状をなすと共に、初期貫通孔２４のうち上側基板３の裏面３Ａ側に開口した部位には、開口端の欠損等によって面取り形状をした環状突起部２４Ａが形成されている。
【００３５】
図５に示す第１の接合工程では、初期貫通孔２４を有する上側基板３の裏面３Ａにシリコン基板２の表面を衝合させる。そして、この状態で、これらを接合温度まで加熱しつつ、上側基板３、シリコン基板２に例えば１０００Ｖ程度の電圧を印加し、該シリコン基板２と下側基板１とを陽極接合等の接合手段を用いて面接合し、貼り合わせる。
【００３６】
図６に示す機能部加工工程では、シリコン基板２の裏面にマスク（図示せず）を成膜した上で、エッチング処理によって凹溝部１５を形成し、シリコン基板２のうち凹溝部１５に対応した位置が薄肉部２Ａとなる。この状態で、角速度検出部１１と枠部１２を型取ったマスク（図示せず）をシリコン基板２の裏面に成膜した上で、シリコン基板２の裏面側からマスクを通してエッチング処理を施し、該シリコン基板２のうち薄肉部２Ａに対応した位置には角速度検出部１１を形成し、その外側には枠部１２を加工する。
【００３７】
図７に示す第２の接合工程では、予めほぼ中央部に電極板１８等が形成された下側基板１によって角速度検出部１１を覆うと共に、下側基板１の表面をシリコン基板２のうち接続部となる支持部１３、各電極支持部１７、引出部１９（図２参照）および枠部１２に当接させる。そして、これらを減圧雰囲気中で陽極接合によって面接合させる。このとき、角速度検出部１１は画成された密閉室４内に封止される。
【００３８】
図８、図９に示す穴加工工程では、上側基板３の表面全面に亘ってサンドブラスト等の穴加工手段を用いて初期貫通孔２４の内壁全面または内壁のうち環状突起部２４Ａを有するシリコン基板２側を研磨する。このとき、初期貫通孔２４は、その内壁が研磨されるから、内径寸法が僅かに拡大し、環状突起部２４Ａは除去される。また、初期貫通孔２４内に露出した電極支持部１７の表面にも穴加工が施されるから、電極支持部１７の表面に浅溝状の凹底部２２が形成され、上側基板３と電極支持部１７との間には、貫通孔２１と凹底部２２とは段差無くテーパ状に連続した内壁を有する。
【００３９】
なお、サンドブラストによる穴加工は上側基板３の表面３Ｃ全面に施すものとしたが、例えば初期貫通孔２４を型取ったマスク（図示せず）を上側基板３の表面側に成膜した上で、初期貫通孔２４内だけを穴加工する構成としてもよい。
【００４０】
さらに、図１０に示す導電膜加工工程は、貫通孔２１の位置に合わせてメタルマスク（図示せず）を上側基板３の表面３Ｃ側に配置し、このメタルマスクをマスクとして例えばスパッタ等の手段を用いて、上側基板３の貫通孔２１の内壁にアルミニウム等の金属薄膜を成膜し、導電膜２３を設ける。このように、穴加工工程と導電膜加工工程とによって、貫通孔２１、凹底部２２および導電膜２３からなるビアホール２０を加工し、導電膜２３のうち上側基板３の表面３Ｃに位置した部位には、ニッケルまたは白金等の電極用下地金属を設ける。
【００４１】
なお、導電膜２３はメタルマスクを通じて金属薄膜を成膜することとしたが、例えば上側基板３の表面全面に導電膜を形成した後、フォトリソグラフィ等を用いて貫通孔２１内等の導電膜を残存させ、他の部位の導電膜を除去する構成としてもよい。
【００４２】
然るに、本実施の形態によれば、初期貫通孔２４を有する上側基板３をシリコン基板２に貼り合わせた後、初期貫通孔２４に穴加工を施すから、サンドブラスト等の穴加工による研磨量を少なくし、加工時間を短くすることができる。このため、例えば単一のウエハ上に形成した多数の角速度センサに同時に穴加工を施す場合であっても、各角速度センサに設けた貫通孔２１の内径寸法等のばらつきをなくすことができ、略同一形状の貫通孔２１を形成することができる。
【００４３】
また、貫通孔２１は初期貫通孔２４の内壁を研磨することによって形成するから、初期貫通孔２４の環状突起部２４Ａを除去することができ、貫通孔２１は、上側基板３と電極支持部１７との間が段差無く連続したテーパ形状をなすと共に、その底面には確実に電極支持部１７を露出させることができる。このため、貫通孔２１内に設けた導電膜２３に段差による断線が生じることがなく、導電膜２３を通じて確実に電極支持部１７と外部との間を電気的に接続することができ、信頼性を向上することができる。
【００４４】
さらに、貫通孔２１を形成するために穴加工時間は短時間ですむから、貫通孔２１がシリコン基板２を貫通することがない。このため、角速度検出部１１の損傷を防止できると共に、密閉室４の密閉性を確保することができるから、歩留を高めて生産性を向上させることができる。
【００４５】
一方、貫通孔２１の開口面積も略等しくすることができるから、導電膜２３と電極支持部１７等の接続部との間のコンタクト抵抗を略等しくすることができる。このため、角速度センサの入力抵抗、出力抵抗のばらつきを抑制し、角速度検出部１１の動作特性、検出特性等を安定化することができる。
【００４６】
次に、図１１ないし図１５は本発明の第２の実施の形態による角速度センサを示し、本実施の形態の特徴は、シリコン基板の上側に配設された上側基板には貫通孔の開口周囲に位置して配線用溝を形成すると共に、該配線用溝には貫通孔内に接続した導電膜を設けたことにある。なお、本実施の形態では、前述した第１の実施の形態と同一の構成要素に同一の符号を付し、その説明を省略するものとする。
【００４７】
３１，３１，…は貫通孔２１の開口近傍に位置して上側基板３の表面３Ｃに設けられた配線用溝で、該配線用溝３１は貫通孔２１よりも浅い深さ寸法をもって上側基板３の表面３Ｃ側に溝状の設けられ、貫通孔２１の開口を取り囲むと共に、その一部が略四角形状の電極部３１Ａをなしている。
【００４８】
３２，３２，…は各貫通孔２１の内壁と配線用溝３１の内壁とに設けられた導電膜で、該導電膜３２は、角速度検出部１１の接続部（支持部１３、各電極支持部１７、引出部１９）から上側基板３の配線用溝３１内に延びている。また、導電膜３２のうち電極部３１Ａ内に位置した部位は、電極パッド３２Ａを構成している。そして、この電極パッド３２Ａに半田バンプ、ワイヤーボンディング等を施すことによって、導電膜３２は角速度検出部１１と外部とを電気的に接続するものである。
【００４９】
次に、図１３ないし図１５に基づいて、本実施の形態による角速度センサの製造方法について述べる。
【００５０】
まず、第１の実施の形態と同様に、貫通孔加工工程によって上側基板３に初期貫通孔２４を形成し、第１の接合工程によって上側基板３とシリコン基板２とを接合した後、機能部加工工程によってシリコン基板２に角速度検出部１１を形成する。そして、第２の接合工程によってシリコン基板２に下側基板１を接合し、角速度検出部１１を下側基板１と上側基板３との間に封止する。
【００５１】
次に、図１４に示す穴加工工程では、配線用溝３１を型取ったマスク（図示せず）を上側基板３の表面３Ｃ側に成膜した上で、初期貫通孔２４にサンドブラスト等の穴加工を施し、上側基板３にテーパ状の貫通孔２１，２１，…を加工する。これにより、上側基板３と電極支持部１７とには、段差無くテーパ状に連続した内壁を有する貫通孔２１と凹底部２２とがそれぞれ形成される。また、この貫通孔２１の形成と同時に、該貫通孔２１の開口近傍には上側基板３の表面３Ｃよりも窪んだ配線用溝３１が形成される。
【００５２】
そして、図１５に示す導電膜加工工程は、上側基板３の表面３Ｃと貫通孔２１、凹底部２２とに全面に亘って導電膜としてのアルミニウム等の金属薄膜３３を成膜する。このとき、貫通孔２１、凹底部２２、配線用溝３１の内壁に金属薄膜３３が形成されると共に、上側基板３の表面３Ｃにも全面に亘って金属薄膜３３が形成される。
【００５３】
その後、表面研磨工程によって上側基板３の表面３Ｃ側を図１５中に仮想線ａ−ａで示す位置まで研磨する。これにより、金属薄膜３３のうち上側基板３の表面３Ｃ上に形成されたものは除去される。一方、金属薄膜３３のうち貫通孔２１、凹底部２２の内壁と配線用溝３１内に形成されたものは、そのまま残存して図１１に示すように導電膜３２となる。
【００５４】
かくして、本実施の形態によっても第１の実施の形態と同様の作用効果を得ることができるが、本実施の形態では、上側基板３の表面よりも窪んだ配線用溝３１内に導電膜３２を形成したから、例えば製造工程の途中で角速度センサを運搬等するときでも導電膜３２が工具等に接触することがなく、導電膜３２の剥離を防止することができる。また、配線用溝３１の電極部３１Ａには電極パッド３２Ａを設けたから、角速度センサを実装した後にはワイヤボンディングが電極部３１Ａ内で電極パッド３２Ａに接続される。このため、電極パッド３２Ａとワイヤボンディングとの接続箇所を配線用溝３１内に配置することができ、これらの接続部位を保護することができる。このため、ワイヤボンディング等を長期間に亘って確実に接続することができ、信頼性、生産性を向上することができる。
【００５５】
また、配線用溝３１によって導電膜３２の配線形状を設定することができるから、例えばメタルマスクを用いて導電膜を成膜する場合に比べてメタルマスクのずれ等が生じることがなく、配線の幅寸法を小さくすることができる。このため、角速度センサを小型化し、製造コストを低減することができる。
【００５６】
なお、各実施の形態では、電子部品として角速度センサを例に挙げて説明したが、本発明はこれに限らず、加速度センサ、メカニカルフィルタ等に適用してもよい。
【００５７】
また、第１，第２の接合工程では、陽極接合を例に挙げて説明したが、接着剤等によって接着してもよく、要はガラス基板とシリコン基板との接着力が確保されればよい。
【００５８】
また、各実施の形態では、貫通孔２１等からなるビアホール２０を角速度検出部１１の電極支持部１７に形成したものを図示して説明したが、これに限らず、角速度検出部１１の接続部をなす支持部１３、引出部１９にも同様にしてビアホール２０を形成している。
【００５９】
さらに、貫通孔２１は、上側基板３に形成する構成としたが、本発明はこれに限らず下側基板１に形成する構成としてもよい。また、本実施の形態では初期貫通孔２４を有する上側基板３をシリコン基板２に接合した後、シリコン基板２に下側基板１を接合するものとしたが、下側基板１をシリコン基板２に接合した後、シリコン基板２に初期貫通孔２４を有する上側基板３を接合する構成としてもよい。
【００６０】
【発明の効果】
以上詳述した通り、請求項１の発明に係る製造方法によれば、初期貫通孔を有するガラス基板と機能部を形成する機能部形成基板とを貼り合わせ、初期貫通孔に穴加工を施した後、加工済み貫通孔の内壁に導電膜を設ける構成としたから、単一のウエハ上に形成した多数の電子部品に同時に穴加工を施す場合であっても、各電子部品毎の加工済み貫通孔の形状ばらつきをなくすことができ、生産性を向上することができる。また、導電膜を通じて確実に機能部と外部との間を電気的に接続することができ、信頼性を向上することができる。さらに、加工済み貫通孔の開口面積も略同一形状とし、導電膜と機能部との間のコンタクト抵抗を略等しくすることができるから、電子部品の入力抵抗、出力抵抗のばらつきを抑制し、電子部品の動作特性、検出特性等を安定化させることができる。
【００６１】
また、請求項２の発明によれば、初期貫通孔の穴加工と同時に初期貫通孔の周囲に溝加工を施してガラス基板の表面に配線用溝を形成したから、ガラス基板の表面全面に導電膜を形成することによって、加工済み貫通孔と配線用溝との内壁に導電膜を設けることができる。そして、この状態でガラス基板の表面に研磨処理等を施すことによって、導電膜のうちガラス基板の表面のものを除去し、加工済み貫通孔と配線用溝との内壁に機能部と外部とを電気的に接続する導電膜を設けることができる。このため、配線用溝を用いてガラス基板の表面に加工済み貫通孔内に接続した配線を形成することができる。また、配線用溝によって導電膜の配線形状を設定することができるから、配線の幅寸法を小さくすることができ、角速度センサ等の電子部品を小型化し、製造コストを低減することができる。
【００６２】
一方、請求項３の発明による電子部品は、初期貫通孔の内壁を削ることによって初期貫通孔に穴加工を施すから、ガラス基板には加工済み貫通孔を形成することができ、初期貫通孔の突起等を除去し、ガラス基板と機能部形成基板との間の段差をなくすことができる。また、ガラス基板の表面よりも窪んだ配線用溝内に導電膜を形成したから、例えば製造工程の途中で電子部品を運搬等するときでも導電膜が工具等に接触することがなく、導電膜の剥離を防止することができ、信頼性を向上することができる。
【００６３】
また、請求項４の発明によれば、導電膜のうち配線用溝内に位置した部位は電極パッドをなすから、電極パッドとなる配線用溝内の導電膜にワイヤーボンディング等を施すことによって、機能部と外部とを電気的に接続することができる。また、電極パッドとワイヤボンディングとの接続箇所を配線用溝内に配置することができるから、これらの接続部位を保護することができ、信頼性、生産性を向上することができる。
【図面の簡単な説明】
【図１】第１の実施の形態による角速度センサを示す断面図である。
【図２】図１の角速度センサを上側基板を取外した状態で示す斜視図である。
【図３】上側基板を初期貫通孔を形成する前の状態で示す断面図である。
【図４】貫通孔加工工程によって上側基板に初期貫通孔を形成した状態を示す断面図である。
【図５】第１の接合工程によって上側基板とシリコン基板とを接合した状態を示す断面図である。
【図６】機能部加工工程によってシリコン基板に角速度検出部を形成した状態を示す断面図である。
【図７】第２の接合工程によってシリコン基板に下側基板を接合した状態を示す断面図である。
【図８】穴加工工程によって上側基板に貫通孔を形成した状態を示す断面図である。
【図９】図８中の貫通孔を拡大して示す拡大断面図である。
【図１０】導電膜加工工程によって貫通孔の内壁に導電膜を形成した状態を示す拡大断面図である。
【図１１】第２の実施の形態による角速度センサを示す断面図である。
【図１２】第２の実施の形態による角速度センサを示す平面図である。
【図１３】シリコン基板に上側基板と下側基板とを接合した状態を示す図７と同様の断面図である。
【図１４】穴加工工程によって上側基板に貫通孔を形成し、上側基板の表面に配線用溝を形成した状態を示す断面図である。
【図１５】導電膜加工工程によって上側基板の表面と貫通孔等の全面に金属薄膜を形成した状態を示す断面図である。
【符号の説明】
１下側基板（ガラス基板）
２シリコン基板
３上側基板（ガラス基板）
１１角速度検出部（機能部）
１２枠部
１３支持部（接続部）
１７電極支持部（接続部）
１９引出部（接続部）
２０ビアホール
２１貫通孔（加工済み貫通孔）
２２凹底部
２３，３２導電膜
２４初期貫通孔
３１配線用溝
３３金属薄膜（導電膜）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic component such as an angular velocity sensor, an acceleration sensor, and a mechanical filter, for example, and relates to an electronic component manufacturing method and an electronic component that derive an electric signal to the outside.
[0002]
[Prior art]
In general, angular velocity sensors, acceleration sensors, mechanical filters, and the like are widely known as electronic components obtained by processing a silicon substrate or the like using a micromachining technique. In addition, this type of electronic component includes, for example, a silicon substrate and a glass substrate that is surface-bonded to the front surface side and the back surface side of the silicon substrate. The silicon substrate is provided with a functional unit that detects angular velocity, for example, and the functional unit is sealed by two glass substrates.
[0003]
In addition, in order to electrically connect the functional part and the outside, a through hole that reaches the silicon substrate through the glass substrate is formed, and a conductive film is provided in the through hole (for example, JP-A-7-263709, JP-A-9-283663, etc.). Then, such an electronic component according to the prior art, after joining the glass substrate and the silicon substrate by anodic bonding, through a glass substrate by sandblasting or the like to expose a part of the silicon substrate, through holes Form. And the electrically conductive film is formed in the inner wall of a through-hole using means, such as a sputter | spatter and vapor deposition.
[0004]
[Problems to be solved by the invention]
However, in the above-described prior art, after the glass substrate and the silicon substrate are joined, hole processing is performed from the surface side of the glass substrate to form a through hole that communicates from the glass substrate to the silicon substrate. Such hole processing is usually performed in a state where a large number of electronic components are formed on the wafer.
[0005]
At this time, the sandblasting speed tends to vary on the wafer surface, and the through hole does not penetrate the glass substrate at a position on the wafer surface and becomes a bottomed hole at another position on the wafer surface. The through hole may also penetrate the silicon substrate. As described above, when the through hole does not penetrate the glass substrate, it is impossible to make an electrical connection with the connection portion of the silicon substrate. On the other hand, when the through hole penetrates the silicon substrate, the functional portion of the silicon substrate is not provided. May also be damaged. For this reason, the defect of an electronic component tends to arise and there exists a problem that productivity falls.
[0006]
In addition, since the opening area of the through hole differs for each electronic component, the contact resistance between the conductive film and the connection portion varies. For this reason, since the input resistance and the output resistance of the electronic component vary, there is a problem that the operation characteristic and detection characteristic of the functional unit are different for each electronic component.
[0007]
The present invention has been made in view of the above-described problems of the prior art. An electronic component manufacturing method and an electronic component that can electrically and reliably connect a functional unit to the outside and improve productivity and reliability. It is intended to provide.
[0008]
[Means for Solving the Problems]
In order to solve the problems described above, Tomorrow , initial A glass substrate having a through hole and a functional part forming substrate for forming a functional part are bonded together, initial Through the through hole initial The through hole is machined, and a conductive film that electrically connects the functional part to the outside is provided on the inner wall of the machined through hole. In the manufacturing method of an electronic component, the protrusion is caused by a defect in an opening end on a side of the glass substrate that is bonded to the functional part forming substrate by cutting an inner wall of the initial through hole in the hole processing. At least, and a step between the glass substrate and the functional part forming substrate is eliminated. The
[0009]
By configuring in this way, initial After surface bonding the glass substrate having a through hole to the functional part forming substrate, initial Through the through hole initial Because the through hole is drilled, initial The inner wall of the through hole can be polished to increase its inner diameter, initial A protrusion or the like generated in the through hole can be removed, and a step between the glass substrate and the functional unit formation substrate can be eliminated. Therefore, by forming a conductive film on the inner wall of the processed through-hole, the conductive film is not disconnected between the glass substrate and the silicon substrate, and the functional part and the outside are electrically connected by the conductive film. can do. Also, initial When drilling through holes, initial Since the inner wall of the through hole only needs to be slightly shaved to such an extent that the protrusions are removed, variation in the shape of the processed through hole due to the hole processing can be reduced.
[0010]
Further, the invention of claim 2 Tomorrow , initial A glass substrate having a through hole and a functional part forming substrate for forming a functional part are bonded together, initial Through the through hole initial While drilling through holes, the glass substrate initial A wiring groove is formed around the through hole, a conductive film is provided over the entire surface of the glass substrate and the processed through hole, and the conductive film on the surface of the glass substrate is removed from the conductive film, A conductive film for electrically connecting the functional part to the outside is provided on the inner wall of the processed through hole and the wiring groove. In the manufacturing method of an electronic component, the protrusion is caused by a defect in an opening end on a side of the glass substrate that is bonded to the functional part forming substrate by cutting an inner wall of the initial through hole in the hole processing. Is removed, and the step between the glass substrate and the functional part forming substrate is eliminated, and in the groove processing, in the vicinity of the opening of the initial through hole formed in the glass substrate, the surface is recessed from the surface of the glass substrate. The wiring groove is formed. The
[0011]
This initial After surface bonding the glass substrate having a through hole to the functional part forming substrate, initial Through the through hole initial Because the through hole is drilled, By cutting the inner wall of the initial through hole, The step of the through hole can be eliminated, and the step between the glass substrate and the functional part forming substrate can be removed. For this reason, the conductive film is not disconnected between the glass substrate and the silicon substrate, and the functional portion and the outside can be electrically connected by the conductive film.
[0012]
Simultaneously with the drilling of the through hole, a groove is formed around the through hole in the glass substrate, and the surface of the glass substrate More hollow Since the wiring groove is formed, the conductive film can be provided on the inner wall of the processed through hole and the wiring groove by forming the conductive film over the entire surface of the glass substrate and the processed through hole. . In this state, the surface of the glass substrate is polished to remove the conductive film on the surface of the glass substrate, and the functional portion and the outside are electrically connected to the inner wall of the through hole and the wiring groove. An electrically conductive film can be provided. For this reason, the wiring connected in the through-hole can be formed in the surface of a glass substrate using the groove | channel for wiring.
[0013]
On the other hand, Tomorrow The glass substrate having the initial through hole and the functional part forming substrate for forming the functional part are bonded together, the initial through hole is processed through the initial through hole, and around the initial through hole in the glass substrate. A wiring groove is formed, and a conductive film that electrically connects the functional part to the outside is provided on the inner wall of the processed through hole and the wiring groove. In the hole processing, at least the protrusion due to the defect of the opening end on the side of the glass substrate bonded to the functional part forming substrate is removed by cutting the inner wall of the initial through hole in the hole processing. Then, the step between the glass substrate and the functional part forming substrate is eliminated, and in the groove processing, the wiring groove is recessed from the surface of the glass substrate in the vicinity of the opening of the through hole formed in the glass substrate. It is characterized by the configuration that forms The
[0014]
With this configuration, Since the initial through hole is drilled by cutting the inner wall of the initial through hole, A processed through-hole can be formed in the glass substrate, and protrusions and the like of the initial through-hole can be removed, and a step between the glass substrate and the functional part forming substrate can be eliminated. In addition, on the surface of the glass substrate, initial Since the wiring groove is provided in the vicinity of the opening of the through hole, a conductive film connected to the inner wall of the processed through hole can be formed on the inner wall of the wiring groove. For this reason, the wiring connected to the processed through-hole can be attached to the wiring groove of the glass substrate.
[0015]
According to a fourth aspect of the present invention, there is provided a portion of the conductive film located in the wiring groove as an electrode pad.
[0016]
As a result, the functional portion and the outside can be electrically connected by performing wire bonding or the like on the conductive film in the wiring groove forming the electrode pad.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an angular velocity sensor will be described as an example of an electronic component according to an embodiment of the present invention, and will be described in detail with reference to the accompanying drawings.
[0018]
First, FIGS. 1 to 10 show a first embodiment of the present invention. In the figure, reference numeral 1 denotes a lower substrate formed of a glass substrate, and a silicon substrate 2 described later is surface bonded to the surface side of the lower substrate 1 by anodic bonding.
[0019]
Reference numeral 2 denotes a silicon substrate as a functional part forming substrate formed of low-resistance single-crystal silicon having conductivity. The silicon substrate 2 is subjected to an etching process so that an angular velocity detection unit 11 and a frame unit which will be described later are provided. 12 is formed.
[0020]
Reference numeral 3 denotes an upper substrate formed of a glass substrate, and the back surface 3A of the upper substrate 3 serves as a bonding surface for bonding to the connection portion of the angular velocity detection unit 11 and the frame portion 12, and the back surface 3A side of the upper substrate 3 An accommodation recess 3B is formed at the center of the upper substrate 3 and the surface 3C of the upper substrate 3 opposite to the back surface 3A is a non-joint surface. The upper substrate 3 is anodically bonded to the connection portion of the angular velocity detection unit 11 and the frame portion 12, and a sealed chamber 4 is defined between the lower substrate 1 and the upper substrate 3.
[0021]
Reference numeral 11 denotes an angular velocity detection unit as a functional unit (external force detection unit). The angular velocity detection unit 11 has a rotational axis XX when an angular velocity Ω acts around the rotational axis XX as shown in FIG. The angular velocity Ω around is detected. The angular velocity detection unit 11 is formed inside the frame 12 by etching the silicon substrate 2.
[0022]
Here, the configuration of the angular velocity detection unit 11 will be described with reference to FIG. Reference numerals 13 and 13 are support portions provided on the lower substrate 1, and 14 is provided in a state of being separated from the surface of the lower substrate 1 by the recessed groove portions 15, and supported by the support portions 13 by the four support beams 16. Each of the vibrating bodies is shown, and the vibrating body 14 can be displaced in the directions indicated by arrows A and B in FIG. Further, comb-like electrodes 14 A and 14 A are provided on both surface sides of the vibrating body 14.
[0023]
Reference numerals 17 and 17 are electrode support portions provided on both sides of the vibrating body 14 and provided on the lower substrate 1, and comb electrodes 17A are provided on both sides of each electrode support portion 17, and each of the comb electrodes 17A meshes with each comb-like electrode 14A of the vibrating body 14 in a separated state.
[0024]
An electrode plate 18 is provided on the surface of the lower substrate 1 so as to be located below the vibrating body 14. The electrode plate 18 is formed of, for example, a conductive metal material, and the vibrating body 14 is indicated by a Coriolis force. When it is displaced in the B direction, the amount of displacement is detected.
[0025]
Reference numeral 19 denotes a lead portion connected to the electrode plate 18. The lead portion 19 extends from the electrode plate 18 and is provided with a wiring portion 19 A made of a conductive metal material provided on the surface of the lower substrate 1 together with the electrode plate 18. And a pad portion 19B made of a silicon material provided on the wiring portion 19A.
[0026]
Here, the support portion 13, the electrode support portions 17 and 17, and the lead portion 19 constitute a connection portion that electrically connects the angular velocity detection portion 11.
[0027]
20, 20,... Are four via holes (only two are shown) formed from the upper substrate 3 to the angular velocity detection unit 11, and each via hole 20 includes a through hole 21 described later and a bottom portion of the through hole 21. And a conductive film 23 provided on the inner wall of the through hole 21 and the concave bottom portion 22. In the embodiment, the via hole 20 is shown only in the case where the via hole 20 is provided in the electrode support portion 17, but via holes are also formed in the support portion 13 and the extraction portion 19 as in FIG. 1.
[0028]
21, 21,... Are tapered through holes 21 provided through the upper substrate 3, and in the through holes 21, the electrode support portions 17 that form connection portions of the silicon substrate 2 are exposed. ing. Each through-hole 21 has, for example, a diameter dimension on the surface 3C side of the upper substrate 3 serving as an opening larger than a diameter dimension on the back surface 3A side. For this reason, the through hole 21 has a tapered shape that gradually decreases in diameter from the surface 3C side of the upper substrate 3 toward the silicon substrate 2 side.
[0029]
.. Are concave bottom portions formed on the silicon substrate 2 at the bottom of the through hole 21, and the concave bottom portion 22 has a wall surface that is smoothly continuous with the through hole 21 without a step, and is substantially It has a circular shallow groove shape.
[0030]
, 23,... Are conductive films provided on the inner walls of the through holes 21 and the concave bottom portion 22, and the conductive films 23 are connected to the connection portions of the angular velocity detection section 11 (support section 13, each electrode support section 17, lead-out). Part 19) extends to the surface 3C side of the upper substrate 3. A portion of the conductive film 23 located on the surface 3C side of the upper substrate 3 constitutes an electrode pad 23A. The conductive film 23 electrically connects the angular velocity detector 11 and the outside by applying solder bumps, wire bonding, or the like to the electrode pads 23A.
[0031]
In the angular velocity sensor configured as described above, a drive signal is applied between the comb-like electrode 14A of the vibrating body 14 and the comb-like electrode 17A of the electrode support portion 17 from an external oscillation circuit through the conductive film 23 and the like. The vibrating body 14 is vibrated in the direction of arrow A. In this state, when an angular velocity Ω around the rotation axis XX acts on the angular velocity sensor, a Coriolis force acts on the vibrating body 14, and the vibrating body 14 is displaced in the direction indicated by the arrow B in accordance with the magnitude of the Coriolis force. Then, the separation distance between the vibrating body 14 and the electrode plate 18 changes.
[0032]
The change in the separation distance is used as a signal due to the capacitance between the vibrating body 14 and the electrode plate 18, and this signal is output to the detection circuit through the conductive film 23. The detection circuit can convert the electrostatic capacitance into a voltage and measure the angular velocity Ω applied around the rotation axis XX.
[0033]
Next, a method for manufacturing the angular velocity sensor according to the present embodiment will be described with reference to FIGS. In the present embodiment, a case where a single angular velocity sensor is manufactured will be described as an example. However, after manufacturing a large number of angular velocity sensors on one silicon substrate 2 (silicon wafer), each angular velocity sensor is separated. It is good also as a structure.
[0034]
First, FIG. 3 shows the upper substrate 3 before forming the initial through holes 24 and the like. Then, in the through hole processing step shown in FIG. 4, an accommodation recess 3 B that accommodates the angular velocity detection unit 11 is formed on the back surface side of the upper substrate 3. In addition, an initial through hole 24 penetrating in the thickness direction is formed in a portion of the upper substrate 3 that is joined to the support portion 13 serving as a connection portion, each electrode support portion 17, and the extraction portion 19. At this time, the initial through hole 24 is formed by using a drilling means such as sandblast from the surface side of the upper substrate 3. For this reason, the initial through-hole 24 has a shape that is gradually reduced in diameter from the front surface side toward the back surface side, and a portion of the initial through-hole 24 that is open on the back surface 3A side of the upper substrate 3 has a missing opening end. Thus, an annular protrusion 24A having a chamfered shape is formed.
[0035]
In the first bonding step shown in FIG. 5, the surface of the silicon substrate 2 is brought into contact with the back surface 3 A of the upper substrate 3 having the initial through hole 24. In this state, while heating them up to the bonding temperature, a voltage of about 1000 V, for example, is applied to the upper substrate 3 and the silicon substrate 2, and bonding means such as anodic bonding between the silicon substrate 2 and the lower substrate 1 is performed. Use surface bonding and paste.
[0036]
In the functional part processing step shown in FIG. 6, after forming a mask (not shown) on the back surface of the silicon substrate 2, the concave groove portion 15 is formed by an etching process, and corresponds to the concave groove portion 15 in the silicon substrate 2. The position is the thin portion 2A. In this state, after forming a mask (not shown) formed of the angular velocity detection unit 11 and the frame 12 on the back surface of the silicon substrate 2, an etching process is performed through the mask from the back surface side of the silicon substrate 2, An angular velocity detecting unit 11 is formed at a position corresponding to the thin portion 2A in the silicon substrate 2, and a frame unit 12 is processed on the outside thereof.
[0037]
In the second bonding step shown in FIG. 7, the angular velocity detection unit 11 is covered with the lower substrate 1 in which the electrode plate 18 and the like are previously formed in the substantially central portion, and the surface of the lower substrate 1 is connected to the silicon substrate 2. It is made to contact | abut to the support part 13 used as a part, each electrode support part 17, the extraction | drawer part 19 (refer FIG. 2), and the frame part 12. FIG. And these are surface-bonded by anodic bonding in a reduced-pressure atmosphere. At this time, the angular velocity detector 11 is sealed in the defined sealed chamber 4.
[0038]
8 and 9, the silicon substrate 2 having the annular protrusion 24 A on the entire inner wall of the initial through hole 24 or the inner wall using the hole processing means such as sandblasting over the entire surface of the upper substrate 3. Polish the side. At this time, since the inner wall of the initial through hole 24 is polished, the inner diameter dimension is slightly enlarged, and the annular protrusion 24A is removed. Further, since the surface of the electrode support portion 17 exposed in the initial through hole 24 is also drilled, a shallow groove-shaped concave bottom portion 22 is formed on the surface of the electrode support portion 17, and the upper substrate 3 and the electrode support are supported. Between the portion 17, the through hole 21 and the concave bottom portion 22 have an inner wall that is continuous in a tapered shape without a step.
[0039]
In addition, although the hole processing by sandblasting was performed on the entire surface 3C of the upper substrate 3, for example, after forming a mask (not shown) with an initial through hole 24 formed on the surface side of the upper substrate 3, It is good also as a structure which drills only the inside of the initial through-hole 24. FIG.
[0040]
Further, in the conductive film processing step shown in FIG. 10, a metal mask (not shown) is arranged on the surface 3C side of the upper substrate 3 in accordance with the position of the through-hole 21, and means such as sputtering is used using this metal mask as a mask. Then, a metal thin film such as aluminum is formed on the inner wall of the through hole 21 of the upper substrate 3 to provide a conductive film 23. As described above, the via hole 20 including the through hole 21, the concave bottom portion 22, and the conductive film 23 is processed by the hole processing step and the conductive film processing step, and the conductive film 23 is located at a portion located on the surface 3 C of the upper substrate 3. Provides an electrode base metal such as nickel or platinum.
[0041]
The conductive film 23 is formed by forming a metal thin film through a metal mask. However, after the conductive film is formed on the entire surface of the upper substrate 3, for example, the conductive film in the through hole 21 or the like is formed using photolithography or the like. It is good also as a structure which leaves and removes the electrically conductive film of another site | part.
[0042]
However, according to the present embodiment, the upper substrate 3 having the initial through hole 24 is bonded to the silicon substrate 2 and then the initial through hole 24 is subjected to hole processing, so that the amount of polishing by hole processing such as sandblasting is reduced. In addition, the processing time can be shortened. For this reason, for example, even when a number of angular velocity sensors formed on a single wafer are drilled at the same time, variations in the inner diameter dimensions and the like of the through holes 21 provided in each angular velocity sensor can be eliminated. The through holes 21 having the same shape can be formed.
[0043]
Further, since the through hole 21 is formed by polishing the inner wall of the initial through hole 24, the annular protrusion 24 A of the initial through hole 24 can be removed, and the through hole 21 has the upper substrate 3 and the electrode support portion 17. The electrode support portion 17 can be reliably exposed on the bottom surface thereof. Therefore, the conductive film 23 provided in the through-hole 21 is not disconnected by a step, and the electrode support portion 17 and the outside can be reliably electrically connected through the conductive film 23. Can be improved.
[0044]
Further, since the hole processing time is short in order to form the through hole 21, the through hole 21 does not penetrate the silicon substrate 2. For this reason, damage to the angular velocity detection unit 11 can be prevented and the sealing property of the sealed chamber 4 can be ensured, so that the yield can be increased and the productivity can be improved.
[0045]
On the other hand, since the opening area of the through hole 21 can be made substantially equal, the contact resistance between the conductive film 23 and the connection portion such as the electrode support portion 17 can be made substantially equal. For this reason, variations in the input resistance and output resistance of the angular velocity sensor can be suppressed, and the operation characteristics, detection characteristics, and the like of the angular velocity detection unit 11 can be stabilized.
[0046]
Next, FIGS. 11 to 15 show an angular velocity sensor according to a second embodiment of the present invention. The feature of the present embodiment is that the upper substrate disposed on the upper side of the silicon substrate has a through-hole periphery. The wiring groove is formed at the position, and the conductive film connected to the through hole is provided in the wiring groove. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.
[0047]
31 are wiring grooves provided on the surface 3C of the upper substrate 3 in the vicinity of the opening of the through hole 21. The wiring groove 31 has a depth dimension shallower than that of the through hole 21. A groove shape is provided on the surface 3 C side, surrounds the opening of the through hole 21, and a part thereof forms a substantially rectangular electrode portion 31 A.
[0048]
32, 32,... Are conductive films provided on the inner wall of each through-hole 21 and the inner wall of the wiring groove 31, and the conductive film 32 is connected to the connection portion (support portion 13, each electrode support portion of the angular velocity detection unit 11). 17 and the lead-out part 19) extend into the wiring groove 31 of the upper substrate 3. Further, a portion of the conductive film 32 located in the electrode portion 31A constitutes an electrode pad 32A. The conductive film 32 electrically connects the angular velocity detector 11 and the outside by applying solder bumps, wire bonding, or the like to the electrode pads 32A.
[0049]
Next, a method for manufacturing the angular velocity sensor according to the present embodiment will be described with reference to FIGS.
[0050]
First, as in the first embodiment, the initial through hole 24 is formed in the upper substrate 3 by the through hole processing step, and the upper substrate 3 and the silicon substrate 2 are bonded by the first bonding step, and then the functional unit. The angular velocity detector 11 is formed on the silicon substrate 2 by a processing process. Then, the lower substrate 1 is bonded to the silicon substrate 2 by the second bonding step, and the angular velocity detection unit 11 is sealed between the lower substrate 1 and the upper substrate 3.
[0051]
Next, in the hole processing step shown in FIG. 14, a mask (not shown) formed with a wiring groove 31 is formed on the surface 3C side of the upper substrate 3, and then a hole such as sandblast is formed in the initial through hole 24. The tapered through holes 21, 21,... Are processed in the upper substrate 3 by processing. As a result, the upper substrate 3 and the electrode support portion 17 are each formed with a through hole 21 and a concave bottom portion 22 each having an inner wall that is continuously tapered without a step. Simultaneously with the formation of the through hole 21, a wiring groove 31 that is recessed from the surface 3 C of the upper substrate 3 is formed in the vicinity of the opening of the through hole 21.
[0052]
In the conductive film processing step shown in FIG. 15, a metal thin film 33 such as aluminum is formed as a conductive film over the entire surface 3 C of the upper substrate 3, the through hole 21, and the concave bottom portion 22. At this time, the metal thin film 33 is formed on the inner walls of the through hole 21, the concave bottom portion 22, and the wiring groove 31, and the metal thin film 33 is also formed on the entire surface 3 C of the upper substrate 3.
[0053]
Thereafter, the surface 3C side of the upper substrate 3 is polished to a position indicated by an imaginary line aa in FIG. 15 by a surface polishing process. Thereby, the metal thin film 33 formed on the surface 3C of the upper substrate 3 is removed. On the other hand, the metal thin film 33 formed in the through hole 21, the inner wall of the concave bottom portion 22 and the wiring groove 31 remains as it is and becomes a conductive film 32 as shown in FIG.
[0054]
Thus, this embodiment can provide the same effects as those of the first embodiment. However, in this embodiment, the conductive film 32 is provided in the wiring groove 31 that is recessed from the surface of the upper substrate 3. For example, even when the angular velocity sensor is transported during the manufacturing process, the conductive film 32 does not come into contact with the tool or the like, and the peeling of the conductive film 32 can be prevented. In addition, since the electrode pad 32A is provided in the electrode portion 31A of the wiring groove 31, wire bonding is connected to the electrode pad 32A in the electrode portion 31A after the angular velocity sensor is mounted. For this reason, the connection part of electrode pad 32A and wire bonding can be arrange | positioned in the groove | channel 31 for wiring, and these connection parts can be protected. For this reason, wire bonding etc. can be reliably connected over a long period of time, and reliability and productivity can be improved.
[0055]
In addition, since the wiring shape of the conductive film 32 can be set by the wiring groove 31, the metal mask is not displaced as compared with the case where the conductive film is formed using a metal mask, for example. The width dimension can be reduced. For this reason, an angular velocity sensor can be reduced in size and manufacturing cost can be reduced.
[0056]
In each embodiment, the angular velocity sensor is described as an example of the electronic component. However, the present invention is not limited to this and may be applied to an acceleration sensor, a mechanical filter, or the like.
[0057]
In the first and second bonding steps, anodic bonding has been described as an example. However, bonding may be performed using an adhesive or the like, and in short, it is only necessary to secure an adhesive force between the glass substrate and the silicon substrate. .
[0058]
Moreover, in each embodiment, although what demonstrated the via hole 20 which consists of the through-hole 21 etc. in the electrode support part 17 of the angular velocity detection part 11 was illustrated and demonstrated, it is not restricted to this, The connection part of the angular velocity detection part 11 Similarly, via holes 20 are formed in the support portion 13 and the lead-out portion 19.
[0059]
Furthermore, although the through hole 21 is formed in the upper substrate 3, the present invention is not limited to this and may be formed in the lower substrate 1. In the present embodiment, the upper substrate 3 having the initial through hole 24 is bonded to the silicon substrate 2 and then the lower substrate 1 is bonded to the silicon substrate 2. However, the lower substrate 1 is bonded to the silicon substrate 2. After bonding, the upper substrate 3 having the initial through holes 24 may be bonded to the silicon substrate 2.
[0060]
【The invention's effect】
As detailed above, according to the manufacturing method according to the invention of claim 1, initial A glass substrate having a through hole and a functional part forming substrate for forming a functional part are bonded together, initial Since it was configured to provide a conductive film on the inner wall of the processed through hole after drilling the through hole, even when simultaneously drilling a large number of electronic components formed on a single wafer, For each electronic component Processed Variations in the shape of the through holes can be eliminated, and productivity can be improved. In addition, the functional portion and the outside can be reliably connected through the conductive film, and the reliability can be improved. further, Processed The opening area of the through-hole is also approximately the same shape, and the contact resistance between the conductive film and the functional part can be made approximately equal, so that variations in the input resistance and output resistance of the electronic component are suppressed, and the operating characteristics of the electronic component The detection characteristics can be stabilized.
[0061]
According to the invention of claim 2, initial Simultaneously with drilling through holes initial Since the groove was formed around the through hole to form the wiring groove on the surface of the glass substrate, by forming a conductive film on the entire surface of the glass substrate, Processed A conductive film can be provided on the inner wall of the through hole and the wiring groove. And in this state, the surface of the glass substrate is removed from the conductive film by applying a polishing treatment to the surface of the glass substrate, Processed A conductive film that electrically connects the functional portion and the outside can be provided on the inner wall of the through hole and the wiring groove. For this reason, the wiring groove is used on the surface of the glass substrate. Processed A wiring connected in the through hole can be formed. Moreover, since the wiring shape of the conductive film can be set by the wiring groove, the wiring width dimension can be reduced, and the angular velocity sensor Electronic parts such as Can be reduced in size, and the manufacturing cost can be reduced.
[0062]
On the other hand, an electronic component according to the invention of claim 3 is Since the initial through hole is drilled by cutting the inner wall of the initial through hole, the processed through hole can be formed on the glass substrate, and the projection and the like of the initial through hole are removed to form the glass substrate and the functional part. A step between the substrate and the substrate can be eliminated. Also, Since the conductive film is formed in the groove for wiring that is recessed from the surface of the glass substrate, the conductive film does not come into contact with the tool or the like even when an electronic component is transported during the manufacturing process. Can be prevented, and the reliability can be improved.
[0063]
Further, according to the invention of claim 4, since the portion of the conductive film located in the wiring groove forms an electrode pad, by performing wire bonding or the like on the conductive film in the wiring groove serving as the electrode pad, The functional unit and the outside can be electrically connected. Moreover, since the connection part of an electrode pad and wire bonding can be arrange | positioned in the groove | channel for wiring, these connection parts can be protected and reliability and productivity can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an angular velocity sensor according to a first embodiment.
2 is a perspective view showing the angular velocity sensor of FIG. 1 with an upper substrate removed. FIG.
FIG. 3 is a cross-sectional view showing the upper substrate in a state before an initial through hole is formed.
FIG. 4 is a cross-sectional view showing a state where initial through holes are formed in an upper substrate by a through hole processing step.
FIG. 5 is a cross-sectional view showing a state in which the upper substrate and the silicon substrate are bonded in the first bonding step.
FIG. 6 is a cross-sectional view showing a state in which an angular velocity detection unit is formed on a silicon substrate by a functional unit processing step.
FIG. 7 is a cross-sectional view showing a state in which a lower substrate is bonded to a silicon substrate by a second bonding step.
FIG. 8 is a cross-sectional view showing a state in which a through hole is formed in the upper substrate by a hole processing step.
FIG. 9 is an enlarged cross-sectional view showing an enlarged through hole in FIG. 8;
FIG. 10 is an enlarged cross-sectional view showing a state in which a conductive film is formed on the inner wall of the through hole by a conductive film processing step.
FIG. 11 is a cross-sectional view showing an angular velocity sensor according to a second embodiment.
FIG. 12 is a plan view showing an angular velocity sensor according to a second embodiment.
13 is a cross-sectional view similar to FIG. 7, showing a state in which an upper substrate and a lower substrate are bonded to a silicon substrate.
FIG. 14 is a cross-sectional view showing a state in which through holes are formed in the upper substrate by a hole processing step, and wiring grooves are formed on the surface of the upper substrate.
FIG. 15 is a cross-sectional view showing a state in which a metal thin film is formed on the entire surface of the upper substrate and the through-holes by the conductive film processing step.
[Explanation of symbols]
1 Lower substrate (glass substrate)
2 Silicon substrate
3 Upper substrate (glass substrate)
11 Angular velocity detector (function unit)
12 Frame
13 Supporting part (connection part)
17 Electrode support (connection)
19 Leader (connector)
20 Beer hall
21 Through hole (Processed through hole)
22 concave bottom
23, 32 conductive film
24 Initial through hole
31 Groove for wiring
33 Metal thin film (conductive film)

Claims

A glass substrate having an initial through hole and a functional part forming substrate for forming a functional part are bonded together, the initial through hole is subjected to hole processing through the initial through hole, and the functional part and the outside are formed on the inner wall of the processed through hole. between an electrically electronic component manufacturing method of consisting be provided with a conductive film connected to,
In the hole processing, by removing the inner wall of the initial through-hole, at least a protrusion due to a defect in the opening end on the side bonded to the functional part forming substrate is removed from the glass substrate, and the glass substrate and the functional part are removed. A method for manufacturing an electronic component, characterized in that a step difference from a formation substrate is eliminated.

Bonding the functional portion substrate for forming a glass substrate and the functional part having an initial through-hole, the wiring around the initial through-hole of the glass substrate is performed with a drilling in the initial holes through the initial through-hole A conductive film is provided over the entire surface of the glass substrate and the processed through hole, and the conductive film on the surface of the glass substrate is removed from the conductive film, and the processed through hole and An electronic component manufacturing method comprising a conductive film that electrically connects the functional unit to the outside on an inner wall with a wiring groove ,
In the hole processing, by removing the inner wall of the initial through-hole, at least a protrusion due to a defect in the opening end on the side bonded to the functional part forming substrate is removed from the glass substrate, and the glass substrate and the functional part are removed. Eliminates the difference between the formation substrate and
In the groove processing, the wiring groove that is recessed from the surface of the glass substrate is formed in the vicinity of the opening of the initial through hole formed in the glass substrate.

A glass substrate having an initial through hole is bonded to a functional part forming substrate for forming a functional part, and the initial through hole is processed through the initial through hole, and wiring is provided around the initial through hole in the glass substrate. An electronic component configured to provide a conductive film for electrically connecting the functional part to the outside on the inner wall of the processed through hole and the wiring groove ,
In the hole processing, by removing the inner wall of the initial through-hole, at least a protrusion due to a defect in the opening end on the side bonded to the functional part forming substrate is removed from the glass substrate, and the glass substrate and the functional part are removed. Eliminates the difference between the formation substrate and
In the groove processing, an electronic component is characterized in that the wiring groove that is recessed from the surface of the glass substrate is formed in the vicinity of the opening of the initial through hole formed in the glass substrate.

The electronic component according to claim 3, wherein a portion of the conductive film located in the wiring groove is an electrode pad.