JP2004273507A - Wire bonding device - Google Patents

Wire bonding device Download PDF

Info

Publication number
JP2004273507A
JP2004273507A JP2003058232A JP2003058232A JP2004273507A JP 2004273507 A JP2004273507 A JP 2004273507A JP 2003058232 A JP2003058232 A JP 2003058232A JP 2003058232 A JP2003058232 A JP 2003058232A JP 2004273507 A JP2004273507 A JP 2004273507A
Authority
JP
Japan
Prior art keywords
bonding
height
semiconductor chip
laser
capillary
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2003058232A
Other languages
Japanese (ja)
Inventor
Kouji Nishimaki
公路 西巻
Original Assignee
Kaijo Corp
株式会社カイジョー
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kaijo Corp, 株式会社カイジョー filed Critical Kaijo Corp
Priority to JP2003058232A priority Critical patent/JP2004273507A/en
Publication of JP2004273507A publication Critical patent/JP2004273507A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L24/00Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/74Apparatus for manufacturing arrangements for connecting or disconnecting semiconductor or solid-state bodies
    • H01L24/78Apparatus for connecting with wire connectors
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/02Bonding areas; Manufacturing methods related thereto
    • H01L2224/04Structure, shape, material or disposition of the bonding areas prior to the connecting process
    • H01L2224/05Structure, shape, material or disposition of the bonding areas prior to the connecting process of an individual bonding area
    • H01L2224/0554External layer
    • H01L2224/0555Shape
    • H01L2224/05552Shape in top view
    • H01L2224/05554Shape in top view being square
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/44Structure, shape, material or disposition of the wire connectors prior to the connecting process
    • H01L2224/45Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/44Structure, shape, material or disposition of the wire connectors prior to the connecting process
    • H01L2224/45Structure, shape, material or disposition of the wire connectors prior to the connecting process of an individual wire connector
    • H01L2224/45001Core members of the connector
    • H01L2224/45099Material
    • H01L2224/451Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof
    • H01L2224/45138Material with a principal constituent of the material being a metal or a metalloid, e.g. boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Po), and alloys thereof the principal constituent melting at a temperature of greater than or equal to 950°C and less than 1550°C
    • H01L2224/45144Gold (Au) as principal constituent
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42Wire connectors; Manufacturing methods related thereto
    • H01L2224/47Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805Shape
    • H01L2224/4809Loop shape
    • H01L2224/48091Arched
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/74Apparatus for manufacturing arrangements for connecting or disconnecting semiconductor or solid-state bodies and for methods related thereto
    • H01L2224/78Apparatus for connecting with wire connectors
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/74Apparatus for manufacturing arrangements for connecting or disconnecting semiconductor or solid-state bodies and for methods related thereto
    • H01L2224/78Apparatus for connecting with wire connectors
    • H01L2224/7825Means for applying energy, e.g. heating means
    • H01L2224/783Means for applying energy, e.g. heating means by means of pressure
    • H01L2224/78301Capillary
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/74Apparatus for manufacturing arrangements for connecting or disconnecting semiconductor or solid-state bodies and for methods related thereto
    • H01L2224/78Apparatus for connecting with wire connectors
    • H01L2224/7825Means for applying energy, e.g. heating means
    • H01L2224/783Means for applying energy, e.g. heating means by means of pressure
    • H01L2224/78313Wedge
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/85Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a wire connector
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/85Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a wire connector
    • H01L2224/852Applying energy for connecting
    • H01L2224/85201Compression bonding
    • H01L2224/85205Ultrasonic bonding
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2224/00Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/85Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a wire connector
    • H01L2224/852Applying energy for connecting
    • H01L2224/8521Applying energy for connecting with energy being in the form of electromagnetic radiation
    • H01L2224/85214Applying energy for connecting with energy being in the form of electromagnetic radiation using a laser
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01004Beryllium [Be]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01005Boron [B]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01006Carbon [C]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01013Aluminum [Al]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01033Arsenic [As]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01039Yttrium [Y]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01067Holmium [Ho]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01079Gold [Au]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01Chemical elements
    • H01L2924/01082Lead [Pb]
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/049Nitrides composed of metals from groups of the periodic table
    • H01L2924/04955th Group
    • H01L2924/04953TaN
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L2924/00Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10Details of semiconductor or other solid state devices to be connected
    • H01L2924/1015Shape
    • H01L2924/1016Shape being a cuboid
    • H01L2924/10161Shape being a cuboid with a rectangular active surface

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wire bonding device which calculates the height of a bonding surface before a bonding operation is started using a laser beam that irradiates the bonding surface, sets up a region for an optimal low-speed operation, and provides a shortest bonding time. <P>SOLUTION: The height of the bonding surface is stored as reference data for bonding, and the spot position of a laser beam θ irradiating the same plane is calculated on the basis of a photoed image and stored. In a practical bonding process, the transferred semiconductor chip 1, a board, or a lead frame as a bonding surface is irradiated with a laser beam 17, the amount of deviation of the irradiated spot from the previously stored spot position is calculated, and a height difference is obtained from the calculated amount of deviation to calculate the height of an actual bonding surface. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【0001】
【発明の属する技術分野】
本発明は、ワイヤボンディング装置におけるボンディング対象である半導体チップの高さ検出および補正に関するものである。
【0002】
【従来の技術】
ワイヤボンダによる接合工程の説明を用いて従来の高さ検出方法を説明する。
図2はボンディング工程を概略的に示したもである。
まず、半導体チップ1がリードフレーム2のアイランド2a上に搭載され、そして、ワークステージ3上に移載される。次に、超音波ホーン4の先端側に取り付けられたキャピラリ5に通された金ワイヤ6の先端に、電気トーチ(図示していない)によりボール6aが形成される。
【0003】
この状態において、カメラ7により検出された、半導体チップ1上のある電極パッド1aの位置に、ホーン4とともにキャピラリ5が下降される。そして、ホーン4を介してキャピラリ5が超音波振動され、また、所定の熱と荷重とが付加されることにより、金ワイヤ6の先端のボール6aが半導体チップ1上の所定の位置の電極パッド1aに接合される。
【0004】
この後、キャピラリ5は金ワイヤ6を少しずつ送り出しながら上昇され、カメラ7により検出されたリードフレーム2のあるリード2bの位置に移動される。そして、キャピラリ5を介して所定の熱と荷重とが付加されることにより、金ワイヤ6が所定の位置のリード2bに圧着される。
【0005】
この状態で、クランパ(図示していない)を引き上げることにより金ワイヤ6は切断され、半導体チップ1の電極パッド1aおよび、リードフレーム2のリード2bの間にループ状に金ワイヤ6が接合される。
【0006】
この後、新たにボール6aの形成が行われて、次のパッド1aへ金ワイヤ6を接合するためにキャピラリ5の移動が制御され、接合の動作が繰返される。
【0007】
図3は、上記したワイヤボンダにおける、接合時の動作シーケンスを示すものである。なお、図3(a1)は、キャピラリ5のZ軸方向のパッドへの下降動作タイミングであり、図3(b1)は、パッド面タッチ検出タイミングであり、図3(c1)は、Z軸方向の制御方式切り換えタイミングでである。また、図3(a2)は、キャピラリ5のZ軸方向のリードへの下降動作タイミングであり、図3(b2)は、リード面タッチ検出タイミングであり、図3(c2)は、Z軸方向の制御方式切り換えタイミングでである。
【0008】
すなわち、従来のボンディング動作は、まず、ボール6aを形成した後、キャピラリ5を所定の電極パッド1aの上方に移動する。そして、その位置からキャピラリ5を高速下降動作させる(図3ステップA)。
【0009】
キャピラリ5の下降が所定のサーチ高さに達すると、その位置からキャピラリ5を等速下降動作(サーチ部)させる(図3ステップB)。そして、ボール6aの電極パッド1aへの接触を検出する、ワーク面タッチ検出のタイミングにおいて、キャピラリ5のZ軸方向の制御を切り換え、超音波振動を発生させる。これにより、半導体チップ1上の所定の電極パッド1aへの金ワイヤ6の接合が行われる。(図3ステュプC)。
【0010】
次に電極パッド1aへの金ワイヤ6のボンディングが終了すると、キャピラリ5のZ軸方向の制御を、荷重制御から位置制御に切り換えて、X軸方向およびY軸方向の動作とともにキャピラリ5をZ軸方向に移動させ、ループの形成を行う。(図3ステップD)。
【0011】
そして、ループの形成にともなうキャピラリ5の下降が、リード2b上の所定のサーチ高さに達すると、その位置からキャピラリ5を等速下降動作(サーチ部)させる。(図3ステップE)
【0012】
同様にして、金ワイヤ6のリード2bへの接触を検出する、ワーク面タッチ検出のタイミングにおいて、キャピラリ6のZ軸方向の制御を切り換え超音波振動を発生させる。これにより、リードフレーム2上の所定のリード2bへの金ワイヤ6の接合が行われる。(図3ステップF)
【0013】
リード2bへの金ワイヤ6のボンディングが終了すると、キャピラリ5のZ軸方向の制御を、荷重制御から位置制御に切り換えてキャピラリ5を上昇させ、金ワイヤ6を切断し、ボール6aの形成を行い、図3ステップG、また、次の電極パッド1aの上方へキャピラリ5を移動させることにより、ワイヤボンディングの1シーケンスが終了する。(図3ステップH)
【0014】
このように、従来においては、ワーク面(半導体チップ1およびリードフレーム2)の高さのばらつきを考慮してサーチ高さを設定し、高速下降動作の後、キャピラリ5の等速下降動作を行って、ワーク面に対する衝突時の衝撃(接合時のインパクト荷重)が一定となるように制御している。
【0015】
この速度を切り換える高さは、ティーチングされたボンディング点の高さを基準として動作させている。
【0016】
たとえば、図4のように、ティーチングしたボンディング点の高さH0に対して、実際にボンディングするものの高さhが高いと、ボンディングツールがボンディング面に高速移動の領域で激突する可能性がある。
【0017】
また、図5のように、ティーチングしたボンディング点の高さH0に対して、実際にボンディングするものの高さhが低いと、低速移動の領域が長くなり、ボンディング時間が遅くなる可能性がある。
【0018】
つまり、ボンディング点の高さ方向のバラツキが大きいものをボンディングする場合は、高速動作の領域での激突を避けるため、低速で動作させる領域を大きくする必要があり、ボンディング時間が遅くなっていた。
【0019】
そこで、ボンディング点の高さ方向のバラツキが大きいものに対して、3つのパッドの高さをボンディングしながら測定し、その結果から残りのパッドの高さを算出し、ボンディングする方法が考えられた。
また、オートフォーカス機能付きのカメラを搭載し、チップの高さを測定する方法も考えられた。
【0020】
【特許文献】
【特許文献1】特開平06―181232公報
【0021】
【特許文献】
【特許文献2】特開平09―260415公報
【0022】
【発明が解決しようとする課題】
しかしながら、この方法でも最初の3ワイヤのボンディングスピード低下は避けられないし、ワイヤ数の少ないものでの効果は期待出来ない。
又、装置に使用されているカメラレンズは、多少、チップの高さ方向のバラツキがあっても画像処理での位置決め精度を維持するために、焦点深度の深いものを使用する。それに対しオートフォーカスで精度良く測定するためには焦点深度が浅い方が有利であり、位置決めに適当なカメラレンズを選択すると、高さ測定に十分な精度が得られないことがある。
【0023】
さらに、ボンディング面の高さ方向のバラツキが大きいものをボンディングする場合は、低速で動作させる領域を大きくする必要があり、その分ボンディングに要する時間が多くなり、生産量も減少するという問題があった。
【0024】
また、1チップの先頭3ワイヤのみ低速領域を大きくして高さを測定し、それ以降のパッド高さを算出する方法もワイヤ数が少ないものに関しては大きなロス時間が発生する。
【0025】
オートフォーカスを用いる方法は、光学系の選択が困難で、高さ測定に十分な精度が得られないことがある。
【0026】
そこで本発明は、ボンディング面を照射するレーザ光を利用し、ボンディング前にボンディング面の高さを算出し、最適な低速動作の領域を設定し、最速なボンディング時間を提供することを目的とする。
【0027】
【課題を解決するための手段】
半導体チップの電極と外部電極を配線するワイヤボンディング装置において、角度θから半導体チップ上に照射するレーザ光と、レーザ光が照射する位置を撮像する撮像手段と、基準として予め記憶した半導体チップ上のレーザ光の位置と新たに搬送されてきた半導体チップ上のレーザ光の位置を比較する手段と、予め記憶した半導体チップと搬送されてきた半導体チップの高さの差を算出する手段を具備したことを特徴とするワイヤボンディング装置。
【0028】
前記記載の半導体チップ高さは、基準の半導体チップ高さ(Z0)と、高さの差(ΔZ)としたことを特徴とする請求項1項記載のワイヤボンディング装置。
【0029】
【発明の実施の形態】
以下に本発明の実施の形態を示す。
図7に示すように、ボンディングヘッドに搭載されているカメラ7、光学レンズ16の光軸に対し、角度(θ)の方向から、レーザ光源17を設置する。
【0030】
この時、図8に示すように、基準の高さとしたい半導体チップ1のある位置にレーザ光のスポットを照射し、それがモニター19のセンター付近に映し出されるようにレーザ光源17を設置する。
【0031】
まず、ボンディング前に基準となる半導体チップ1の高さを、超音波ホーン4を動作させ、キャピラリ5が半導体チップ1に接触した高さを、Zエンコーダ18から読み込み、記憶する。(Z0)
【0032】
それと同時に基準となる半導体チップ1上に映し出され、光学レンズ16,カメラ7を通して画像処理部20に画像信号として送られたレーザ光のスポット中心(X0)を画像処理により算出する。
【0033】
実際にボンディングを行う場合、ワークステージ3に搬送された半導体チップ1上にレーザ光を照射する。図9のように、この画像も光学レンズ16,カメラ7を通して画像処理部10に送られ、レーザ光のスポット中心(X1)を画像処理により算出する。
【0034】
算出された位置はから、基準の半導体チップとの高さの差(ΔZ)は、
基準の半導体チップとの高さの差ΔZ=(X1−X0)・tanθ..(1)
となる。
【0035】
したがって、実際にこの半導体チップ1の面にボンディングを行う場合は、基準の半導体チップの高さ(Z0)+高さの差(ΔZ)をこの半導体チップ1の高さとしてボンディングすれば良い。
【0036】
つまり、この高さを基準に最低限必要な低速動作範囲となるように設定することが可能となり、ボンディング時間を最速化することが出来る。
【0037】
【発明の効果】
以上説明したように、本発明の方法においては、ボンディング前にボンディング点の高さが既知となり、最短の低速動作の範囲を設定できることにより、ボンディング時間を最速化し、生産量の向上をはかることが出来る。
【図面の簡単な説明】
【図1】本発明の、装置構成を示すブロック図である。
【図2】従来技術とその問題点を説明するために、ワイヤボンダによる接合の手順を概略的に示す斜視図である。
【図3】従来技術とその問題点を説明するために、ワイヤボンディングにおけるボンディングツールのZ方向の動作を示した図である。
【図4】従来技術とその問題点を説明するために、基準のボンディング高さより実際のボンディング高さが高い場合を示した図である。
【図5】従来技術とその問題点を説明するために、基準のボンディング高さより実際のボンディング高さが低い場合を示した図である。
【図6】高さの違う物体に照射されたレーザ光の位置を示した図である。
【図7】レーザ光源の設置位置を示した図である。
【図8】基準のチップにおける高さとレーザ光の位置を示した図である。
【図9】実際にボンディングするチップにおける高さとレーザ光の位置を示した図である。
【符号の説明】
1 半導体チップ
1a 電極パッド
2 リードフレーム
2a リードフレームのアイランド部
2b リード
3 ワークステージ
4 超音波ホーン
5 キャピラリ
6 金ワイヤ
6a 金ボール
7 カメラ
11 XYテーブル
16 光学レンズ
17 レーザ光源
18 Zエンコーダ
19 モニター
20 画像処理部
21 XYステージおよびボンディングヘッド制御部
22 搬送制御部
θ レーザー光角度
[0001]
BACKGROUND OF THE INVENTION
The present invention relates to height detection and correction of a semiconductor chip to be bonded in a wire bonding apparatus.
[0002]
[Prior art]
A conventional height detection method will be described with reference to a bonding process using a wire bonder.
FIG. 2 schematically shows the bonding process.
First, the semiconductor chip 1 is mounted on the island 2 a of the lead frame 2 and then transferred onto the work stage 3. Next, a ball 6 a is formed by an electric torch (not shown) at the tip of the gold wire 6 passed through the capillary 5 attached to the tip of the ultrasonic horn 4.
[0003]
In this state, the capillary 5 is lowered together with the horn 4 at the position of a certain electrode pad 1 a on the semiconductor chip 1 detected by the camera 7. Then, the capillary 5 is ultrasonically oscillated through the horn 4 and a predetermined heat and load are applied, whereby the ball 6a at the tip of the gold wire 6 is placed on the electrode pad at a predetermined position on the semiconductor chip 1. It is joined to 1a.
[0004]
Thereafter, the capillary 5 is lifted while feeding out the gold wire 6 little by little, and is moved to the position of the lead 2b with the lead frame 2 detected by the camera 7. Then, by applying predetermined heat and load through the capillary 5, the gold wire 6 is crimped to the lead 2b at a predetermined position.
[0005]
In this state, the gold wire 6 is cut by pulling up the clamper (not shown), and the gold wire 6 is joined in a loop between the electrode pad 1a of the semiconductor chip 1 and the lead 2b of the lead frame 2. .
[0006]
Thereafter, a new ball 6a is formed, the movement of the capillary 5 is controlled to bond the gold wire 6 to the next pad 1a, and the bonding operation is repeated.
[0007]
FIG. 3 shows an operation sequence at the time of joining in the wire bonder described above. 3 (a1) shows the lowering operation timing of the capillary 5 to the pad in the Z-axis direction, FIG. 3 (b1) shows the pad surface touch detection timing, and FIG. 3 (c1) shows the Z-axis direction. This is the control system switching timing. 3 (a2) shows the lowering operation timing of the capillary 5 toward the lead in the Z-axis direction, FIG. 3 (b2) shows the lead surface touch detection timing, and FIG. 3 (c2) shows the Z-axis direction. This is the control system switching timing.
[0008]
That is, in the conventional bonding operation, first, after forming the ball 6a, the capillary 5 is moved above the predetermined electrode pad 1a. Then, the capillary 5 is moved down at a high speed from that position (step A in FIG. 3).
[0009]
When the descending of the capillary 5 reaches a predetermined search height, the capillary 5 is lowered at a constant speed (search part) from that position (step B in FIG. 3). Then, at the timing of the work surface touch detection for detecting the contact of the ball 6a with the electrode pad 1a, the control in the Z-axis direction of the capillary 5 is switched to generate ultrasonic vibration. As a result, the gold wire 6 is bonded to the predetermined electrode pad 1a on the semiconductor chip 1. (FIG. 3 Step C).
[0010]
Next, when the bonding of the gold wire 6 to the electrode pad 1a is completed, the control in the Z-axis direction of the capillary 5 is switched from the load control to the position control, and the capillary 5 is moved along the Z-axis along with the operations in the X-axis direction and the Y-axis direction. Move in the direction to form a loop. (FIG. 3, Step D).
[0011]
When the lowering of the capillary 5 due to the formation of the loop reaches a predetermined search height on the lead 2b, the capillary 5 is lowered at a constant speed (search part) from that position. (Fig. 3, Step E)
[0012]
Similarly, the control of the capillary 6 in the Z-axis direction is switched and ultrasonic vibration is generated at the timing of the work surface touch detection for detecting the contact of the gold wire 6 with the lead 2b. Thereby, the gold wire 6 is joined to the predetermined lead 2b on the lead frame 2. (Figure 3 Step F)
[0013]
When the bonding of the gold wire 6 to the lead 2b is completed, the control in the Z-axis direction of the capillary 5 is switched from load control to position control, the capillary 5 is raised, the gold wire 6 is cut, and the ball 6a is formed. In FIG. 3, step G, and by moving the capillary 5 above the next electrode pad 1a, one sequence of wire bonding is completed. (Fig. 3, Step H)
[0014]
As described above, in the prior art, the search height is set in consideration of the variation in the height of the work surface (semiconductor chip 1 and lead frame 2), and the capillary 5 is lowered at a constant speed after the high-speed lowering action. Thus, the impact at the time of collision with the workpiece surface (impact load at the time of joining) is controlled to be constant.
[0015]
The height for switching the speed is operated based on the height of the teaching bonding point.
[0016]
For example, as shown in FIG. 4, if the height h of what is actually bonded is higher than the height H0 of the teaching bonding point, the bonding tool may collide with the bonding surface in the region of high-speed movement.
[0017]
Further, as shown in FIG. 5, if the height h of what is actually bonded is lower than the height H0 of the teaching bonding point, the low-speed movement region becomes long and the bonding time may be delayed.
[0018]
That is, in the case of bonding a bonding point having a large variation in the height direction, it is necessary to enlarge a region operated at a low speed in order to avoid a collision in a high-speed operation region, resulting in a slow bonding time.
[0019]
Therefore, a method was considered in which the heights of the three pads were measured while bonding, and the remaining pad heights were calculated from the results for bonding with large variations in the bonding point height direction. .
In addition, a method of measuring the height of the chip by mounting a camera with an autofocus function was also considered.
[0020]
[Patent Literature]
[Patent Document 1] Japanese Patent Laid-Open No. 06-181232
[Patent Literature]
[Patent Document 2] JP 09-260415 A
[Problems to be solved by the invention]
However, even with this method, a reduction in the bonding speed of the first three wires is inevitable, and an effect with a small number of wires cannot be expected.
Further, the camera lens used in the apparatus has a deep focal depth in order to maintain the positioning accuracy in the image processing even if there is some variation in the height direction of the chip. On the other hand, in order to measure accurately with autofocus, it is advantageous that the depth of focus is shallow, and if a camera lens suitable for positioning is selected, sufficient accuracy for height measurement may not be obtained.
[0023]
In addition, when bonding with a large variation in the height direction of the bonding surface, it is necessary to enlarge the area to be operated at a low speed, which increases the time required for bonding and reduces the production amount. It was.
[0024]
Also, the method of measuring the height by increasing the low speed region of only the first three wires of one chip and calculating the pad height after that causes a large loss time for those with a small number of wires.
[0025]
In the method using autofocus, it is difficult to select an optical system, and sufficient accuracy for height measurement may not be obtained.
[0026]
Therefore, the present invention aims to provide the fastest bonding time by using the laser beam that irradiates the bonding surface, calculating the height of the bonding surface before bonding, setting the optimum low-speed operation region, and so on. .
[0027]
[Means for Solving the Problems]
In a wire bonding apparatus for wiring an electrode of a semiconductor chip and an external electrode, a laser beam irradiated onto the semiconductor chip from an angle θ, an imaging means for imaging a position irradiated with the laser beam, and a semiconductor chip stored in advance as a reference Means for comparing the position of the laser light with the position of the laser light on the newly transported semiconductor chip, and means for calculating the height difference between the semiconductor chip stored in advance and the semiconductor chip transported A wire bonding apparatus.
[0028]
The wire bonding apparatus according to claim 1, wherein the semiconductor chip height is a reference semiconductor chip height (Z0) and a height difference (ΔZ).
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
As shown in FIG. 7, a laser light source 17 is installed from the direction of an angle (θ) with respect to the optical axes of the camera 7 and the optical lens 16 mounted on the bonding head.
[0030]
At this time, as shown in FIG. 8, a laser light spot is radiated to a position where the semiconductor chip 1 to be set as a reference height is irradiated, and the laser light source 17 is installed so as to be projected near the center of the monitor 19.
[0031]
First, the height of the reference semiconductor chip 1 before bonding is operated by operating the ultrasonic horn 4 and the height at which the capillary 5 is in contact with the semiconductor chip 1 is read from the Z encoder 18 and stored. (Z0)
[0032]
At the same time, the spot center (X0) of the laser beam that is displayed on the reference semiconductor chip 1 and sent as an image signal to the image processing unit 20 through the optical lens 16 and the camera 7 is calculated by image processing.
[0033]
When bonding is actually performed, laser light is irradiated onto the semiconductor chip 1 transported to the work stage 3. As shown in FIG. 9, this image is also sent to the image processing unit 10 through the optical lens 16 and the camera 7, and the spot center (X1) of the laser light is calculated by image processing.
[0034]
From the calculated position, the height difference (ΔZ) from the reference semiconductor chip is
Difference in height from the reference semiconductor chip ΔZ = (X1−X0) · tan θ. . (1)
It becomes.
[0035]
Therefore, when bonding is actually performed on the surface of the semiconductor chip 1, the height of the reference semiconductor chip (Z0) + the difference in height (ΔZ) may be bonded as the height of the semiconductor chip 1.
[0036]
In other words, it is possible to set the minimum required low speed operation range based on this height, and the bonding time can be maximized.
[0037]
【The invention's effect】
As described above, in the method of the present invention, the height of the bonding point is known before bonding, and the shortest low-speed operation range can be set, so that the bonding time can be maximized and the production volume can be improved. I can do it.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an apparatus configuration of the present invention.
FIG. 2 is a perspective view schematically showing a joining procedure using a wire bonder in order to explain the conventional technique and its problems.
FIG. 3 is a diagram illustrating an operation in a Z direction of a bonding tool in wire bonding in order to explain a conventional technique and its problems.
FIG. 4 is a diagram illustrating a case where an actual bonding height is higher than a reference bonding height in order to explain the related art and its problems.
FIG. 5 is a diagram showing a case where an actual bonding height is lower than a reference bonding height in order to explain the conventional technique and its problems.
FIG. 6 is a diagram showing the position of laser light irradiated to objects having different heights.
FIG. 7 is a diagram showing the installation position of a laser light source.
FIG. 8 is a diagram showing a height and a position of a laser beam in a reference chip.
FIG. 9 is a diagram showing a height and a position of a laser beam in a chip to be actually bonded.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Semiconductor chip 1a Electrode pad 2 Lead frame 2a Island part 2b of lead frame Lead 3 Work stage 4 Ultrasonic horn 5 Capillary 6 Gold wire 6a Gold ball 7 Camera 11 XY table 16 Optical lens 17 Laser light source 18 Z encoder 19 Monitor 20 Image Processing unit 21 XY stage and bonding head control unit 22 Transport control unit θ Laser beam angle

Claims (2)

半導体チップの電極と外部電極を配線するワイヤボンディング装置において、角度θから半導体チップ上に照射するレーザ光と、レーザ光が照射する位置を撮像する撮像手段と、基準として予め記憶した半導体チップ上のレーザ光の位置と新たに搬送されてきた半導体チップ上のレーザ光の位置を比較する手段と、予め記憶した半導体チップと搬送されてきた半導体チップの高さの差を算出する手段を具備したことを特徴とするワイヤボンディング装置。In a wire bonding apparatus for wiring an electrode of a semiconductor chip and an external electrode, a laser beam irradiated on the semiconductor chip from an angle θ, an imaging means for imaging a position irradiated with the laser beam, and a semiconductor chip stored in advance as a reference Means for comparing the position of the laser light with the position of the laser light on the newly transported semiconductor chip, and means for calculating the difference in height between the semiconductor chip stored in advance and the semiconductor chip transported A wire bonding apparatus. 前記記載の半導体チップ高さは、基準の半導体チップ高さ(Z0)と、高さの差(ΔZ)としたことを特徴とする請求項1項記載のワイヤボンディング装置。The wire bonding apparatus according to claim 1, wherein the semiconductor chip height is a reference semiconductor chip height (Z0) and a height difference (ΔZ).
JP2003058232A 2003-03-05 2003-03-05 Wire bonding device Pending JP2004273507A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2003058232A JP2004273507A (en) 2003-03-05 2003-03-05 Wire bonding device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2003058232A JP2004273507A (en) 2003-03-05 2003-03-05 Wire bonding device

Publications (1)

Publication Number Publication Date
JP2004273507A true JP2004273507A (en) 2004-09-30

Family

ID=33121392

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2003058232A Pending JP2004273507A (en) 2003-03-05 2003-03-05 Wire bonding device

Country Status (1)

Country Link
JP (1) JP2004273507A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101133131B1 (en) 2006-04-06 2012-04-06 삼성테크윈 주식회사 Method of bonding wire
CN103262229A (en) * 2011-09-28 2013-08-21 株式会社华祥 Bonding device
WO2018038113A1 (en) * 2016-08-23 2018-03-01 株式会社新川 Wire bonding method and wire bonding device

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101133131B1 (en) 2006-04-06 2012-04-06 삼성테크윈 주식회사 Method of bonding wire
CN103262229A (en) * 2011-09-28 2013-08-21 株式会社华祥 Bonding device
US8651355B2 (en) 2011-09-28 2014-02-18 Kaijo Corporation Bonding apparatus
TWI460802B (en) * 2011-09-28 2014-11-11 Kaijo Kk Jointing device
WO2018038113A1 (en) * 2016-08-23 2018-03-01 株式会社新川 Wire bonding method and wire bonding device
US11004821B2 (en) 2016-08-23 2021-05-11 Shinkawa Ltd. Wire bonding method and wire bonding apparatus

Similar Documents

Publication Publication Date Title
US20180304411A1 (en) Systems and methods for forming apertures in microfeature workpieces
JP4694900B2 (en) Laser processing method
TWI609732B (en) Laser processing device
TW200815134A (en) Laser beam machining system
CN102950383B (en) Method for punching and laser processing device
JP2005329436A (en) Laser machining method
JP2009184002A (en) Laser beam machining method
JP2006289388A (en) Apparatus for laser beam machining
JP5420890B2 (en) Device for measuring the height position of the workpiece held on the chuck table
JP2011108708A (en) Method of processing wafer
JP2011253866A (en) Division method
JP2004273507A (en) Wire bonding device
JP2003163234A (en) Apparatus and method for wire bonding
TW584719B (en) Method and device for measuring the amplitude of a freely oscillating capillary of a wire bonder
JP6461311B2 (en) Wire bonding apparatus and wire bonding method
KR100491371B1 (en) Bonding device
JP2019118949A (en) Processing device
JPH11243113A (en) Wire bonding device
JP2011108709A (en) Method of processing wafer
JPH069215B2 (en) Positioning device
JP2006080139A (en) Wire bonding apparatus
JP2021028082A (en) Laser processing device and method for processing workpiece
TW202106433A (en) Processing performance confirmation method for laser processing apparatus
JPH11214428A (en) Bonding device
JP3083448B2 (en) Laser processing method and apparatus