JP4057265B2

JP4057265B2 - High frequency probe

Info

Publication number: JP4057265B2
Application number: JP2001277515A
Authority: JP
Inventors: めぐみ竹本; 滋樹前川
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2001-09-13
Filing date: 2001-09-13
Publication date: 2008-03-05
Anticipated expiration: 2021-09-13
Also published as: JP2003084010A

Description

【０００１】
【発明の属する技術分野】
この発明は、高周波電気信号の計測に使用するプローブに関し、特に半導体集積回路などの高周波デバイスの電気的特性の測定に使用する高周波プローブに関するものである。
【０００２】
【従来の技術】
図９は、例えば特開平１１―１５３６１８号公報に記載される従来の高周波プローブの構造を示す断面図である。なおこの場合、被測定物である高周波デバイス１の信号電極とグラウンド電極とは同一平面上になく、グラウンド電極はデバイス１の裏面全体に形成されたものとし、デバイス１を載置するデバイスステージ８を高周波デバイス１のグラウンド電極として機能させる。
図に示すように、高周波デバイス１の信号電極パッドにコンタクトする針２からの高周波信号をコネクタ３により取り出し、外部の計測器に伝送するための信号線としてマイクロストリップライン４を用い、このマイクロストリップライン４が表面に形成されたプリント基板５は裏面のベタグラウンド面を金属ブロック６に電気的に接触させた上で固定される。金属ブロック６にはスプリングプローブ７が設けられ、デバイスステージ８にスプリングプローブ７を押し当てる構造となる。また、信号線のインピーダンス不整合、特にマイクロストリップライン４と針２との間の不整合を無くすために、マイクロストリップライン４および針２上を、金属ブロック６に接続された金属板９で囲いキャビティ構造が形成される。これにより、このキャビティ全体でグラウンド電極８に接続される構造となる。
また、針２が信号電極パッドとコンタクトしたとき、即ちたわませた状態の針２と、金属板９および金属ブロック６とが平行になるよう、金属板９および金属ブロック６は曲線形状に形成される。
【０００３】
【発明が解決しようとする課題】
以上のように構成される従来の高周波プローブでは、被測定物である高周波デバイス１の信号電極とグラウンド電極とが同一平面上でない場合に適用でき、インピーダンス整合を取り良好な高周波伝送特性が得られる。しかしながら、針２の先端位置と金属ブロック６に設けられたスプリングプローブ７の位置との距離がある程度以上必要であるため、高周波デバイスの信号電極とグラウンド電極とが近接して配置されている場合には適用できなかった。また、プローブと電極との接触時に確実に接触しているかどうかの確認が、上方からの画像確認だけでは困難であるという問題点もあった。
【０００４】
この発明は、上記のような問題点を解消するために成されたものであって、高周波デバイスの信号電極とグラウンド電極とが近接して、かつ同一平面上にない場合でも、信号電極、グラウンド電極への良好で安定したコンタクトを得て高周波デバイスの正確な高周波特性を測定できる高周波プローブの構造を提供することを目的とする。また、高周波デバイスの信号電極、グラウンド電極へのコンタクトが確実に為されていることを容易に確認できることを目的とする。
【０００５】
【課題を解決するための手段】
この発明の請求項１に係る高周波プローブは、信号伝送路となる信号線を可撓性の絶縁材料で覆い該絶縁材料で構成される突出基板を上記高周波プローブ本体から突出させて備え、該突出基板が、裏面をグラウンド面とし、上記高周波デバイスの上記信号電極、上記グラウンド電極にそれぞれ接触する信号用電極部、グラウンド用電極部を該突出基板先端部の表面に配するマイクロストリップ構造であり、上記信号用電極部、上記グラウンド用電極部を上記信号線、上記グラウンド面に、それぞれ上記突出基板に設けたスルーホールを介して接続し、上記突出基板の裏面の上記グラウンド面上に、先端部に配した所定の厚さの弾性体を介して補強金属板を設け、上記突出基板先端部にて、該突出基板表面の信号用電極部、グラウンド用電極部を上記高周波デバイスの信号電極、グラウンド電極にそれぞれ同時に接触させる際に発生する上記突出基板の撓みを、上記弾性体で吸収させるようにしたものである。
【０００６】
この発明の請求項２に係る高周波プローブは、請求項１において、補強金属板に該補強金属板のひずみを検出する抵抗体からなるひずみゲージを設けたものである。
【０００７】
この発明の請求項３に係る高周波プローブは、請求項１において、補強金属板の突出基板と反対側に、上記補強金属板先端部の変位を検出するレーザ変位計を、上記補強金属板と離間させて設けたものである。
【０００８】
この発明の請求項４に係る高周波プローブは、請求項１〜３のいずれか１項において、信号用電極部およびグラウンド用電極部を突起電極で構成したものである。
【０００９】
この発明の請求項５に係る高周波プローブは、請求項１〜３のいずれか１項において、グラウンド用電極部を、突起電極で構成された信号用電極部およびその周囲領域を除く突出基板表面全体に形成したものである。
【００１０】
この発明の請求項６に係る高周波プローブは、請求項４または５において、突出基板表面に形成された突起電極の表面を、ビッカーズ硬度（Ｈｖ）４０を下らない金属膜でコーティングしたものである。
【００１１】
この発明の請求項７に係る高周波プローブは、請求項４または５において、スルーホール内に金属材料からなる接触端子を、突出基板表面から突出させて設け、該接触端子で突起電極を構成したものである。
【００１２】
この発明の請求項８に係る高周波プローブは、請求項１〜７のいずれか１項において、突出基板の先端部に表面から裏面のグランド面に貫通するスリットを設け、該スリットにより分断された一片の表面に信号用電極部を配し、該信号用電極部と他片の表面に形成されたグラウンド用電極部とを、高周波デバイスの上記信号電極、上記グラウンド電極にそれぞれ接触させるものである。
【００１３】
この発明の請求項９に係る高周波プローブは、請求項８において、信号線を、スリットと所定の距離を有して配設したものである。
【００１４】
この発明の請求項１０に係る高周波プローブは、請求項１〜９のいずれか１項において、高周波デバイスのグラウンド電極と電気的に導通したデバイスステージを該高周波デバイスのグラウンド電極として、突出基板に形成されたグラウンド用電極部を上記デバイスステージに接触させるものである。
【００１５】
この発明の請求項１１に係る高周波プローブは、請求項１〜１０のいずれか１項において、突出基板は高周波プローブの本体側に向かって徐々に幅が太くなる等応力構造である。
【００１６】
【発明の実施の形態】
実施の形態１．
以下、この発明の実施の形態１を図について説明する。
図１は、この発明の実施の形態１による高周波プローブの全体構成を示す図であり、図１（ａ）は平面図、図１（ｂ）は図１（ａ）のＡ−Ａ線による断面図である。
図において、１１はプローブ本体側の固定箇所から先端に向けて突出した突出基板、１１ａは図示しない高周波デバイスの電極に押し当てる突出基板先端部、１２は外部測定器への接続部分となるコネクタ、１３はプローブをテスタに固定する部材、１４は突出基板先端部１１ａからコネクタ１２まで配設された信号線、１５はプローブ自体の特性インピーダンスを被測定物であるデバイスに合わせて測定器とのインピーダンスを整合するための抵抗、１６は突出基板先端部１１ａ上に設けられた弾性体、１７は空洞、１８は突出基板１１を補強する補強金属板で、突出基板先端部１１ａでは弾性体１６を介してその上に設けられる。
【００１７】
図１で示す突出基板先端部１１ａの詳細を図２に示す。図２（ａ）は平面図、図２（ｂ）は斜視図（イメージ図）である。また、プローブ先端部分と被検査物である高周波デバイスとのテスト時の接触状態のイメージ図を図３に示す。なお、図３では、高周波デバイス１の裏面のグラウンド電極と電気的に導通したデバイスステージ８を高周波デバイス１のグラウンド電極として機能させ、突出基板に形成されたグラウンド用電極部２２をデバイスステージ８に接触させるものである。
図１〜図３に示すように、突出基板１１はプローブの本体側に向かって徐々に幅が太くなる形状で形成され、信号線１４をポリミドフィルム等の可撓性の絶縁材料１９で覆って構成すると共に、被検査物と接触しない裏面側が金属薄板から成るベタグラウンド面２０であるマイクロストリップ構造をしている。この絶縁材料１９の厚さ、誘電率および信号線１４の幅は被検査物である高周波デバイスの特性インピーダンスによって決定される。
また、突出基板先端部１１ａの表面（被検査物と接触側）には、信号用電極部としてのバンプ電極２１（以下、信号用突起電極２１と称す）およびグラウンド用電極部としてのバンプ電極２２（以下、グラウンド用突起電極２２と称す）が形成され、これらはベタグラウンド面２０および信号線１４からスルーホール２３ａ、２３ｂを介してそれぞれ接続される。なお、図２（ｂ）および図３では、図示の便宜上、スルーホール２３ａ、２３ｂが突出基板１１の先端面に露出するように形成されているが、若干内側に形成される方が、スルーホール２３ａ、２３ｂおよび突起電極２１、２２の形成の信頼性が高く、望ましい。
【００１８】
また図３に示すように、測定時には、高周波デバイス１の信号電極としての信号パッド２４、グラウンド電極となるデバイスステージ８に、それぞれ信号用突起電極２１、グラウンド用突起電極２２を押し当てて接触させる。このとき、信号パッド２４とデバイスステージ８とが同一平面上でなく段差を有する場合、可撓性の絶縁材料１９で構成される突出基板先端部１１ａは、補強金属板１８により弾性体１６を介して上方から押圧されることにより上記段差に沿って撓み、弾性体１６が収縮してその撓みが吸収される。これにより、信号用突起電極２１およびグラウンド用突起電極２２は、確実に信号パッド２４およびデバイスステージ８に接触して、安定した電気的導通が得られ、高周波デバイス１の高周波特性を信頼性良く測定できる。
【００１９】
以上のようにこの実施の形態では、高周波デバイス１の信号電極（信号パッド２４）とグラウンド電極（デバイスステージ８）とが近接して配置された場合に、これらの電極が同一平面上でなくても、プローブと良好な接触状態が得られ、高周波デバイス１の高周波特性を信頼性良く測定できる。また、可撓性の絶縁材料１９で構成される突出基板先端部１１ａを高周波デバイス１の電極間の段差に沿って撓ませ、その上に設けられた弾性体１６を収縮させるため、小さい押圧力で確実な接触状態が得られ、高周波デバイス１側へのダメージも低減できる。
またこの実施の形態では、突出基板１１をプローブの本体側に向かって徐々に幅が太くなる形状とすることにより、先端部１１ａが高周波デバイス１と接触する際に根元部で大きくなる応力を分散することができ、突出基板１１全体で等応力構造とすることができる。これにより、先端部１１ａが繰り返し高周波デバイス１と接触する突出基板１１を、応力に対して強い構造とすることができる。
【００２０】
なお、弾性体１６に隣接する部分は空洞１７としたが、弾性体１６に比べて十分ヤング率の小さな弾性体を挿入しても良い。
また、信号用突起電極２および１グラウンド用突起電極２２は、その表面をＰｔなどビッカーズ硬度（Ｈｖ）が４０を下らない硬質の金属膜でコーティングしても良く、これにより、摩耗しにくくなり耐久性が増す。
【００２１】
実施の形態２．
上記実施の形態１では、突出基板先端部１１ａ表面にグラウンド用突起電極２２を設けたが、図４に示すように、高周波デバイス１との接触側である突出基板１１表面全体にグラウンド用電極部としての金属薄板２５（以下、グラウンド用電極膜２５と称す）を形成しても良い。この場合、信号用突起電極２１およびその周囲領域には切り欠き部２６を設けて、グラウンド用電極膜２５と信号用突起電極２１とを絶縁する。なおこの場合、グラウンド用電極膜２５と裏面のベタグラウンド面２０とは、２つまたはそれ以上のスルーホールにより接続しても良い。
これにより、信号線１４は上下のグラウンド線（ベタグラウンド面２０、グラウンド用電極膜２５）で挟まれ、高周波伝送特性が向上する。
【００２２】
実施の形態３．
図５は、この発明の実施の形態３による突出基板先端部１１ａの平面図および斜視図（イメージ図）である。図に示すように、突出基板先端部１１ａに、表面から裏面に貫通するスリット２７を設け、このスリット２７により分断された一片の表面に信号用突起電極２１を配設する。また信号線１４は、突出基板先端部１１ａではスリットと所定の距離を保って平行に配設する。このようにスリット２７を設け、分断された一片の表面に信号用突起電極２１を配し、この信号用突起電極２１と他片の表面に形成されたグラウンド用電極膜２５とを、高周波デバイス１の信号パッド２４とデバイスステージ８とにそれぞれ接触させる。これにより、高周波デバイス側の信号パッド２４とデバイスステージ８とに段差を有しても、プローブ側の電極２１、２５はスリット２７により分離されているため、信号パッド２４とデバイスステージ８とのそれぞれの高さに容易に合わせることができ、良好な接触状態が容易で確実に得られる。
また、上記実施の形態２では、グラウンド用電極膜２５に切り欠き部２６を設けて信号用突起電極２１と絶縁したが、図５（ｂ）に示すように、全面に形成したグラウンド用電極膜２５表面の、信号用突起電極２１形成領域およびその周囲領域を絶縁膜２８で覆った後、この絶縁膜２８上に信号用突起電極２１を形成するようにしても良い。
【００２３】
なお、スリット２７は１本のみでなく、図６に示すように２本設けても良い。また図６に示すように、例えばタングステン等、摩耗しにくい金属材料からなる接触端子２９をスルーホール２３ａ内に突出基板表面から突出させて設けても良く、通常のバンプ電極２１と共に突起電極を構成することで、突起電極２１、２９の摩耗に対する耐久性がさらに向上し、高周波デバイス側とプローブ側とのさらに安定した接触状態が得られる。なお、接触端子２９のみで突起電極を構成することもできる。
【００２４】
実施の形態４．
図７は、この発明の実施の形態４による高周波プローブの先端部分を示したもので、図７（ａ）は平面図、図７（ｂ）は図７（ａ）の先端側（左側）から見た側断面図、図７（ｃ）は図７（ａ）のＢ−Ｂ線による断面図である。
図に示すように、補強金属板１８上に抵抗体で構成されるひずみゲージ３０を設ける。これにより、測定時に突出基板先端部１１ａが高周波デバイス１と接触した際に発生する補強金属板１８のひずみ（撓み）が、ひずみゲージ３０の抵抗の変化により検出できる。
突出基板先端部１１ａが高周波デバイス１と接触する際、ほとんどスクラブしないため、上方からの画像確認だけでは接触状態の確認は困難であるが、ひずみゲージ３０を設けて補強金属板１８のひずみを検出することにより、確実に接触しているかどうかの確認が容易に可能になる。
【００２５】
なお、接触状態の確認は、図８（ａ）に示すように、補強金属板１８上方に補強金属板先端部の変位を検出するレーザ変位計３１を設けても良く、突出基板先端部１１ａが高周波デバイス１と接触した際に発生する補強金属板先端部のひずみによる変位が容易に検出できて、接触状態の確認が容易に可能になる。
また、レーザ変位計３１は設置空間に余裕がない場合は、図８（ｂ）に示すように、ミラーなどの反射物３２ａ、３２ｂを設けて、照射したレーザー光の反射光を検出するようにしても良く、同様の効果が得られる。
【００２６】
【発明の効果】
以上のようにこの発明の請求項１に係る高周波プローブは、信号伝送路となる信号線を可撓性の絶縁材料で覆い該絶縁材料で構成される突出基板を上記高周波プローブ本体から突出させて備え、該突出基板が、裏面をグラウンド面とし、高周波デバイスの信号電極、グラウンド電極にそれぞれ接触する信号用電極部、グラウンド用電極部を該突出基板先端部の表面に配するマイクロストリップ構造であり、上記信号用電極部、上記グラウンド用電極部を上記信号線、上記グラウンド面に、それぞれ上記突出基板に設けたスルーホールを介して接続したため、高周波デバイスの信号電極とグラウンド電極とが近接して配置された場合に、これらの電極が同一平面上でなくても、突出基板先端部がその段差に沿って撓んで高周波デバイスと良好な接触状態が得られ高周波特性を信頼性良く測定できる。また、突出基板の裏面のグラウンド面上に、先端部に配した所定の厚さの弾性体を介して補強金属板を設け、上記突出基板先端部にて、該突出基板表面の信号用電極部、グラウンド用電極部を高周波デバイスの信号電極、グラウンド電極にそれぞれ同時に接触させる際に発生する上記突出基板の撓みを、上記弾性体で吸収させるようにしたため、高周波デバイスとの良好な接触状態が安定して容易に得ることができ、安定した電気的導通により高周波特性を信頼性良く測定できる。
【００２７】
またこの発明の請求項２に係る高周波プローブは、請求項１において、補強金属板に該補強金属板のひずみを検出する抵抗体からなるひずみゲージを設けたため、高周波デバイスとの接触状態を容易に確認できる。
【００２８】
またこの発明の請求項３に係る高周波プローブは、請求項１において、補強金属板の突出基板と反対側に、上記補強金属板先端部の変位を検出するレーザ変位計を、上記補強金属板と離間させて設けたため、高周波デバイスとの接触状態を容易に確認できる。
【００２９】
またこの発明の請求項４に係る高周波プローブは、請求項１〜３のいずれか１項において、信号用電極部およびグラウンド用電極部を突起電極で構成したため、高周波デバイスと良好な接触状態が確実に得られる。
【００３０】
またこの発明の請求項５に係る高周波プローブは、請求項１〜３のいずれか１項において、グラウンド用電極部を、突起電極で構成された信号用電極部およびその周囲領域を除く突出基板表面全体に形成したため、高周波デバイスと良好な接触状態が確実に得られると共に、高周波伝送特性が向上し、高周波特性をさらに信頼性良く測定できる。
【００３１】
またこの発明の請求項６に係る高周波プローブは、請求項４または５において、突出基板表面に形成された突起電極の表面を、ビッカーズ硬度（Ｈｖ）４０を下らない金属膜でコーティングしたため、突起電極が摩耗しにくくなり耐久性が向上する。
【００３２】
またこの発明の請求項７に係る高周波プローブは、請求項４または５において、スルーホール内に金属材料からなる接触端子を、突出基板表面から突出させて設け、該接触端子で突起電極を構成したため、突起電極が摩耗しにくくなり耐久性が向上する。
【００３３】
またこの発明の請求項８に係る高周波プローブは、請求項１〜７のいずれか１項において、突出基板の先端部に表面から裏面のグランド面に貫通するスリットを設け、該スリットにより分断された一片の表面に信号用電極部を配し、該信号用電極部と他片の表面に形成されたグラウンド用電極部とを、高周波デバイスの上記信号電極、上記グラウンド電極にそれぞれ接触させるため、高周波デバイスの信号電極とグラウンド電極との段差に沿って突出基板先端部を容易に撓ませることができ、良好な接触状態が容易で確実に得られる。
【００３４】
またこの発明の請求項９に係る高周波プローブは、請求項８において、信号線を、スリットと所定の距離を有して配設したため、高周波信号を信頼性良く伝送できる。
【００３５】
またこの発明の請求項１０に係る高周波プローブは、請求項１〜９のいずれか１項において、高周波デバイスのグラウンド電極と電気的に導通したデバイスステージを該高周波デバイスのグラウンド電極として、突出基板に形成されたグラウンド用電極部を上記デバイスステージに接触させるため、グラウンド電極との安定した接触状態が得られる。
【００３６】
またこの発明の請求項１１に係る高周波プローブは、請求項１〜１０のいずれか１項において、突出基板は高周波プローブの本体側に向かって徐々に幅が太くなる等応力構造であるため、繰り返し高周波デバイスと接触する突出基板を、応力に対して強い構造とすることができる。
【図面の簡単な説明】
【図１】この発明の実施の形態１による高周波プローブの全体構成を示す平面図および断面図である。
【図２】この発明の実施の形態１による高周波プローブの突出基板先端部の詳細を示す平面図および斜視図である。
【図３】この発明の実施の形態１による高周波プローブ先端部分と高周波デバイスとの接触状態のイメージ図である。
【図４】この発明の実施の形態２による高周波プローブの突出基板先端部の詳細を示す斜視図である。
【図５】この発明の実施の形態３による高周波プローブの突出基板先端部の詳細を示す平面図および斜視図である。
【図６】この発明の実施の形態３の別例による高周波プローブの突出基板先端部の詳細を示す斜視図である。
【図７】この発明の実施の形態４による高周波プローブの先端部分を示す平面図および断面図である。
【図８】この発明の実施の形態４の別例による高周波プローブの先端部分を示す断面図である。
【図９】従来の高周波プローブの構造を示す断面図である。
【符号の説明】
１高周波デバイス、８デバイスステージ、１１突出基板、
１１ａ突出基板先端部、１２コネクタ、１４信号線、１６弾性体、
１８補強金属板、１９絶縁材料、２０ベタグラウンド面、
２１信号用電極部としての信号用突起電極、
２２グラウンド用電極部としてのグラウンド用突起電極、
２３ａ，２３ｂスルーホール、２４信号電極としての電極パッド、
２５グラウンド用電極部としてのグラウンド用電極膜、２６切り欠き部、
２７スリット、２８絶縁膜、２９接触端子、３０ひずみゲージ、
３１，３１ａレーザ変位計。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a probe used for measuring a high-frequency electric signal, and more particularly to a high-frequency probe used for measuring electrical characteristics of a high-frequency device such as a semiconductor integrated circuit.
[0002]
[Prior art]
FIG. 9 is a cross-sectional view showing the structure of a conventional high-frequency probe described in, for example, JP-A-11-153618. In this case, it is assumed that the signal electrode and the ground electrode of the high-frequency device 1 that is the object to be measured are not on the same plane, and the ground electrode is formed on the entire back surface of the device 1, and the device stage 8 on which the device 1 is placed. Function as a ground electrode of the high-frequency device 1.
As shown in the figure, a microstrip line 4 is used as a signal line for taking out a high frequency signal from a needle 2 contacting a signal electrode pad of the high frequency device 1 by a connector 3 and transmitting it to an external measuring instrument. The printed circuit board 5 on which the lines 4 are formed is fixed after the solid ground surface on the back surface is brought into electrical contact with the metal block 6. A spring probe 7 is provided on the metal block 6, and the spring probe 7 is pressed against the device stage 8. Further, in order to eliminate signal line impedance mismatch, particularly mismatch between the microstrip line 4 and the needle 2, the microstrip line 4 and the needle 2 are surrounded by a metal plate 9 connected to the metal block 6. A cavity structure is formed. As a result, the entire cavity is connected to the ground electrode 8.
Further, when the needle 2 contacts the signal electrode pad, that is, the bent needle 2 is parallel to the metal plate 9 and the metal block 6, the metal plate 9 and the metal block 6 are formed in a curved shape. Is done.
[0003]
[Problems to be solved by the invention]
The conventional high-frequency probe configured as described above can be applied when the signal electrode and the ground electrode of the high-frequency device 1 that is the object to be measured are not on the same plane, and impedance matching is achieved and good high-frequency transmission characteristics are obtained. . However, since the distance between the tip position of the needle 2 and the position of the spring probe 7 provided on the metal block 6 is required to some extent, the signal electrode of the high-frequency device and the ground electrode are arranged close to each other. Could not be applied. In addition, there is a problem that it is difficult to confirm whether or not the probe and the electrode are in contact with each other by only confirming the image from above.
[0004]
The present invention has been made in order to solve the above-described problems. Even when the signal electrode and the ground electrode of the high-frequency device are close to each other and are not on the same plane, the signal electrode and the ground are provided. An object of the present invention is to provide a structure of a high-frequency probe capable of obtaining a good and stable contact with an electrode and measuring an accurate high-frequency characteristic of a high-frequency device. It is another object of the present invention to be able to easily confirm that the signal electrode and ground electrode of the high-frequency device are reliably contacted.
[0005]
[Means for Solving the Problems]
According to a first aspect of the present invention, a high-frequency probe includes a projecting substrate configured by covering a signal line serving as a signal transmission path with a flexible insulating material and projecting from the main body of the high-frequency probe. The substrate has a microstrip structure in which the back surface is a ground surface, the signal electrode of the high-frequency device, the signal electrode portion that contacts the ground electrode, and the ground electrode portion on the surface of the tip of the protruding substrate, The signal electrode portion and the ground electrode portion are connected to the signal line and the ground surface through through holes provided in the protruding substrate, respectively , and a tip portion is formed on the ground surface on the back surface of the protruding substrate. A reinforcing metal plate is provided via an elastic body having a predetermined thickness disposed on the signal board, and a signal electrode part and a ground electrode part on the surface of the protruding board. The above high-frequency device of the signal electrode, the deflection of the protruding substrate that occurs when their respective simultaneously contacted to the ground electrode, in which so as to absorb in the elastic body.
[0006]
A high-frequency probe according to a second aspect of the present invention is the high-frequency probe according to the first aspect, wherein the reinforcing metal plate is provided with a strain gauge made of a resistor for detecting the strain of the reinforcing metal plate.
[0007]
A high-frequency probe according to a third aspect of the present invention is the high-frequency probe according to the first aspect, wherein a laser displacement meter for detecting the displacement of the tip of the reinforcing metal plate is separated from the reinforcing metal plate on the side opposite to the protruding substrate of the reinforcing metal plate. It is provided.
[0008]
A high-frequency probe according to a fourth aspect of the present invention is the high-frequency probe according to any one of the first to third aspects , wherein the signal electrode portion and the ground electrode portion are constituted by protruding electrodes.
[0009]
A high-frequency probe according to a fifth aspect of the present invention is the high-frequency probe according to any one of the first to third aspects , wherein the ground electrode portion is the entire protruding substrate surface excluding the signal electrode portion constituted by the protruding electrode and the surrounding area. Is formed.
[0010]
A high-frequency probe according to a sixth aspect of the present invention is the high-frequency probe according to the fourth or fifth aspect, wherein the surface of the protruding electrode formed on the protruding substrate surface is coated with a metal film having a Vickers hardness (Hv) of 40.
[0011]
A high-frequency probe according to a seventh aspect of the present invention is the high-frequency probe according to the fourth or fifth aspect , wherein a contact terminal made of a metal material is provided in the through hole so as to protrude from the surface of the protruding substrate, and a protruding electrode is constituted by the contact terminal. It is.
[0012]
A high-frequency probe according to an eighth aspect of the present invention is the high-frequency probe according to any one of the first to seventh aspects , wherein a slit penetrating from the front surface to the ground surface on the rear surface is provided at the tip of the protruding substrate, and the piece divided by the slit The signal electrode portion is disposed on the surface of the high-frequency device, and the signal electrode portion and the ground electrode portion formed on the surface of the other piece are brought into contact with the signal electrode and the ground electrode of the high-frequency device, respectively.
[0013]
A high-frequency probe according to a ninth aspect of the present invention is the high-frequency probe according to the eighth aspect, wherein the signal line is disposed with a predetermined distance from the slit.
[0014]
A high-frequency probe according to a tenth aspect of the present invention is the high-frequency probe according to any one of the first to ninth aspects , wherein the device stage electrically connected to the ground electrode of the high-frequency device is formed on the protruding substrate as the ground electrode of the high-frequency device. The ground electrode portion thus made is brought into contact with the device stage.
[0015]
The high-frequency probe according to an eleventh aspect of the present invention is the iso-stress structure according to any one of the first to tenth aspects , wherein the protruding substrate gradually increases in width toward the main body side of the high-frequency probe.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings.
1A and 1B are diagrams showing an overall configuration of a high-frequency probe according to Embodiment 1 of the present invention. FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view taken along line AA in FIG. FIG.
In the figure, 11 is a protruding substrate that protrudes toward the tip from a fixed location on the probe body side, 11a is a protruding substrate tip that presses against an electrode of a high-frequency device (not shown), and 12 is a connector that becomes a connection part to an external measuring instrument, 13 is a member for fixing the probe to the tester, 14 is a signal line disposed from the protruding substrate tip 11a to the connector 12, and 15 is an impedance with the measuring instrument in accordance with the characteristic impedance of the probe itself to the device to be measured. 16 is an elastic body provided on the protruding substrate tip 11a, 17 is a cavity, 18 is a reinforcing metal plate that reinforces the protruding substrate 11, and the protruding substrate tip 11a is interposed via the elastic body 16. On it.
[0017]
Details of the protruding substrate tip 11a shown in FIG. 1 are shown in FIG. 2A is a plan view, and FIG. 2B is a perspective view (image diagram). Further, FIG. 3 shows an image diagram of a contact state at the time of a test between the probe tip portion and the high-frequency device which is an inspection object. In FIG. 3, the device stage 8 electrically connected to the ground electrode on the back surface of the high-frequency device 1 is caused to function as the ground electrode of the high-frequency device 1, and the ground electrode portion 22 formed on the protruding substrate is used as the device stage 8. It is to be contacted.
As shown in FIGS. 1 to 3, the protruding substrate 11 is formed in a shape that gradually increases in width toward the main body side of the probe, and the signal line 14 is covered with a flexible insulating material 19 such as a polyimide film. The microstrip structure is configured such that the back surface side that does not contact the object to be inspected is a solid ground surface 20 made of a thin metal plate. The thickness of the insulating material 19, the dielectric constant, and the width of the signal line 14 are determined by the characteristic impedance of the high-frequency device that is the object to be inspected.
In addition, bump electrodes 21 as signal electrodes (hereinafter referred to as signal projection electrodes 21) and bump electrodes 22 as ground electrodes are formed on the surface of the protruding substrate tip 11a (on the side in contact with the object to be inspected). (Hereinafter referred to as a ground protruding electrode 22) are formed, and these are connected from the solid ground surface 20 and the signal line 14 through the through holes 23a and 23b, respectively. In FIGS. 2B and 3, for convenience of illustration, the through holes 23a and 23b are formed so as to be exposed at the front end surface of the protruding substrate 11, but the through holes are formed slightly inside. The formation of the 23a and 23b and the protruding electrodes 21 and 22 is desirable because of high reliability.
[0018]
As shown in FIG. 3, at the time of measurement, the signal projection electrode 21 and the ground projection electrode 22 are pressed and brought into contact with the signal pad 24 as the signal electrode of the high-frequency device 1 and the device stage 8 as the ground electrode, respectively. . At this time, when the signal pad 24 and the device stage 8 are not on the same plane but have a step, the protruding substrate front end portion 11 a made of the flexible insulating material 19 is interposed by the reinforcing metal plate 18 via the elastic body 16. By being pressed from above, it bends along the step, and the elastic body 16 contracts to absorb the bend. As a result, the signal protruding electrode 21 and the ground protruding electrode 22 reliably come into contact with the signal pad 24 and the device stage 8 to obtain stable electrical conduction, and reliably measure the high-frequency characteristics of the high-frequency device 1. it can.
[0019]
As described above, in this embodiment, when the signal electrode (signal pad 24) of the high-frequency device 1 and the ground electrode (device stage 8) are arranged close to each other, these electrodes are not on the same plane. However, a good contact state with the probe can be obtained, and the high frequency characteristics of the high frequency device 1 can be measured with high reliability. Further, since the protruding substrate tip 11a made of the flexible insulating material 19 is bent along the step between the electrodes of the high frequency device 1, and the elastic body 16 provided thereon is contracted, a small pressing force is applied. Thus, a reliable contact state can be obtained, and damage to the high frequency device 1 can be reduced.
In this embodiment, the protruding substrate 11 has a shape that gradually increases in width toward the main body side of the probe, so that the stress that increases at the root portion when the tip portion 11a contacts the high-frequency device 1 is dispersed. Therefore, the entire protruding substrate 11 can have an isostress structure. Thereby, the protrusion board | substrate 11 in which the front-end | tip part 11a contacts the high frequency device 1 repeatedly can be made into a structure strong against stress.
[0020]
Although the portion adjacent to the elastic body 16 is the cavity 17, an elastic body having a sufficiently small Young's modulus compared to the elastic body 16 may be inserted.
Further, the surface of the signal protruding electrode 2 and the ground protruding electrode 22 may be coated with a hard metal film having a Vickers hardness (Hv) of not less than 40, such as Pt. Increase.
[0021]
Embodiment 2. FIG.
In the first embodiment, the ground protruding electrode 22 is provided on the surface of the protruding substrate tip portion 11a. However, as shown in FIG. 4, the ground electrode portion is formed on the entire surface of the protruding substrate 11 that is in contact with the high frequency device 1. A thin metal plate 25 (hereinafter referred to as a ground electrode film 25) may be formed. In this case, a notch 26 is provided in the signal projection electrode 21 and the surrounding area to insulate the ground electrode film 25 from the signal projection electrode 21. In this case, the ground electrode film 25 and the backside solid ground surface 20 may be connected by two or more through holes.
As a result, the signal line 14 is sandwiched between the upper and lower ground lines (solid ground surface 20, ground electrode film 25), and high-frequency transmission characteristics are improved.
[0022]
Embodiment 3 FIG.
5A and 5B are a plan view and a perspective view (image diagram) of a protruding substrate tip portion 11a according to Embodiment 3 of the present invention. As shown in the figure, a slit 27 penetrating from the front surface to the back surface is provided in the protruding substrate front end portion 11a, and the signal protruding electrode 21 is disposed on the surface of one piece divided by the slit 27. The signal line 14 is arranged in parallel with a predetermined distance from the slit at the protruding substrate tip 11a. Thus, the slit 27 is provided, the signal projection electrode 21 is arranged on the divided surface, and the signal electrode 21 and the ground electrode film 25 formed on the surface of the other piece are connected to the high-frequency device 1. The signal pad 24 and the device stage 8 are brought into contact with each other. As a result, even if there is a step between the signal pad 24 on the high frequency device side and the device stage 8, the electrodes 21 and 25 on the probe side are separated by the slits 27. Therefore, a good contact state can be easily and reliably obtained.
In the second embodiment, the notch 26 is provided in the ground electrode film 25 to insulate it from the signal projection electrode 21. However, as shown in FIG. 5B, the ground electrode film formed on the entire surface. The signal projection electrode 21 may be formed on the insulating film 28 after the signal projection electrode 21 formation region and its surrounding region on the surface of 25 are covered with the insulating film 28.
[0023]
Note that not only one slit 27 but also two slits 27 may be provided as shown in FIG. Further, as shown in FIG. 6, for example, contact terminals 29 made of a metal material which is not easily worn, such as tungsten, may be provided in the through holes 23 a so as to protrude from the surface of the protruding substrate, and constitute a protruding electrode together with a normal bump electrode 21. By doing so, the durability against the abrasion of the protruding electrodes 21 and 29 is further improved, and a more stable contact state between the high-frequency device side and the probe side can be obtained. It should be noted that the protruding electrode can be constituted by only the contact terminal 29.
[0024]
Embodiment 4 FIG.
FIG. 7 shows a tip portion of a high-frequency probe according to Embodiment 4 of the present invention. FIG. 7 (a) is a plan view, and FIG. 7 (b) is from the tip side (left side) of FIG. 7 (a). FIG. 7C is a sectional view taken along line B-B in FIG.
As shown in the figure, a strain gauge 30 made of a resistor is provided on the reinforcing metal plate 18. Thereby, the distortion | strain (deflection) of the reinforcement metal plate 18 which generate | occur | produces when the protrusion board | substrate front-end | tip part 11a contacts the high frequency device 1 at the time of a measurement can be detected by the change of resistance of the strain gauge 30.
When the protruding substrate tip 11a contacts the high-frequency device 1, it hardly scrubs. Therefore, it is difficult to confirm the contact state only by confirming the image from above, but the strain gauge 30 is provided to detect the strain of the reinforcing metal plate 18. By doing so, it is possible to easily confirm whether or not the contact is made reliably.
[0025]
As shown in FIG. 8A, the contact state may be confirmed by providing a laser displacement meter 31 for detecting the displacement of the front end portion of the reinforcing metal plate 18 above the reinforcing metal plate 18. The displacement due to the strain at the tip of the reinforcing metal plate generated when contacting the high frequency device 1 can be easily detected, and the contact state can be easily confirmed.
In addition, when there is not enough space in the installation space of the laser displacement meter 31, as shown in FIG. 8B, reflectors 32a and 32b such as mirrors are provided to detect the reflected light of the irradiated laser light. The same effect can be obtained.
[0026]
【The invention's effect】
As described above, in the high-frequency probe according to the first aspect of the present invention, the signal line serving as the signal transmission path is covered with the flexible insulating material, and the protruding substrate made of the insulating material is protruded from the main body of the high-frequency probe. The projecting substrate has a microstrip structure in which the back surface is a ground surface, and the signal electrode of the high-frequency device, the signal electrode portion that contacts the ground electrode, and the ground electrode portion are arranged on the front surface of the projecting substrate. Since the signal electrode portion and the ground electrode portion are connected to the signal line and the ground surface through the through holes provided in the protruding substrate, the signal electrode of the high-frequency device and the ground electrode are close to each other. When arranged, even if these electrodes are not on the same plane, the tip of the protruding substrate bends along the step and is good as a high-frequency device. The tactile obtaining the state high-frequency characteristics can reliably measured. Further, a reinforcing metal plate is provided on the ground surface on the back surface of the protruding substrate via an elastic body having a predetermined thickness disposed at the tip, and the signal electrode portion on the surface of the protruding substrate is provided at the tip of the protruding substrate. In addition, the elastic body absorbs the bending of the protruding substrate that occurs when the ground electrode is simultaneously in contact with the signal electrode and ground electrode of the high-frequency device, so that the good contact state with the high-frequency device is stable. Therefore, high frequency characteristics can be measured with high reliability by stable electrical conduction.
[0027]
According to a second aspect of the present invention, in the high-frequency probe according to the first aspect, since the strain gauge made of a resistor for detecting the strain of the reinforcing metal plate is provided on the reinforcing metal plate, the contact state with the high-frequency device can be easily achieved. I can confirm.
[0028]
A high-frequency probe according to a third aspect of the present invention is the high-frequency probe according to the first aspect, wherein a laser displacement meter for detecting the displacement of the tip of the reinforcing metal plate is provided on the side opposite to the protruding substrate of the reinforcing metal plate, and the reinforcing metal plate. Since they are provided apart from each other, the contact state with the high-frequency device can be easily confirmed.
[0029]
According to a fourth aspect of the present invention, in the high frequency probe according to any one of the first to third aspects , since the signal electrode portion and the ground electrode portion are constituted by protruding electrodes, a good contact state with the high frequency device is ensured. Is obtained.
[0030]
A high-frequency probe according to a fifth aspect of the present invention is the high frequency probe according to any one of the first to third aspects , wherein the ground electrode portion is the protruding substrate surface excluding the signal electrode portion constituted by the protruding electrode and the surrounding area. Since it is formed as a whole, a good contact state with the high-frequency device can be surely obtained, the high-frequency transmission characteristic is improved, and the high-frequency characteristic can be measured with higher reliability.
[0031]
According to a sixth aspect of the present invention, in the high frequency probe according to the fourth or fifth aspect , since the surface of the protruding electrode formed on the protruding substrate surface is coated with a metal film having a Vickers hardness (Hv) of 40, the protruding electrode is Less wear and improved durability.
[0032]
According to a seventh aspect of the present invention, in the high frequency probe according to the fourth or fifth aspect , the contact terminal made of a metal material is provided in the through hole so as to project from the surface of the projecting substrate, and the projecting electrode is constituted by the contact terminal. As a result, the protruding electrode is less likely to be worn and durability is improved.
[0033]
The high-frequency probe according to an eighth aspect of the present invention is the high-frequency probe according to any one of the first to seventh aspects , wherein a slit penetrating from the front surface to the ground surface on the rear surface is provided at the tip of the protruding substrate, and is divided by the slit. A signal electrode portion is arranged on one surface, and the signal electrode portion and the ground electrode portion formed on the surface of the other piece are brought into contact with the signal electrode and the ground electrode of the high-frequency device, respectively. The tip of the protruding substrate can be easily bent along the step between the signal electrode and the ground electrode of the device, and a good contact state can be easily and reliably obtained.
[0034]
The high-frequency probe according to claim 9 of the present invention, in claim 8, the signal lines, since the arranged has a slit with a predetermined distance, a high-frequency signal can be transmitted reliably.
[0035]
A high-frequency probe according to a tenth aspect of the present invention is the high-frequency probe according to any one of the first to ninth aspects , wherein the device stage electrically connected to the ground electrode of the high-frequency device is used as a ground electrode of the high-frequency device. Since the formed ground electrode portion is brought into contact with the device stage, a stable contact state with the ground electrode can be obtained.
[0036]
According to an eleventh aspect of the present invention, in the radio frequency probe according to any one of the first to tenth aspects , the protruding substrate has an iso-stress structure in which the width gradually increases toward the main body side of the high frequency probe. The protruding substrate that comes into contact with the high-frequency device can have a structure strong against stress.
[Brief description of the drawings]
1A and 1B are a plan view and a cross-sectional view showing an overall configuration of a high-frequency probe according to Embodiment 1 of the present invention.
FIGS. 2A and 2B are a plan view and a perspective view showing details of a protruding substrate tip portion of the high-frequency probe according to Embodiment 1 of the present invention. FIGS.
FIG. 3 is an image diagram of a contact state between a high-frequency probe tip and a high-frequency device according to Embodiment 1 of the present invention.
FIG. 4 is a perspective view showing details of a protruding substrate tip portion of a high-frequency probe according to Embodiment 2 of the present invention.
FIGS. 5A and 5B are a plan view and a perspective view showing details of a protruding substrate tip portion of a high-frequency probe according to Embodiment 3 of the present invention. FIGS.
FIG. 6 is a perspective view showing details of a protruding substrate tip portion of a high-frequency probe according to another example of Embodiment 3 of the present invention.
7A and 7B are a plan view and a cross-sectional view showing a distal end portion of a high-frequency probe according to Embodiment 4 of the present invention.
FIG. 8 is a sectional view showing a tip portion of a high-frequency probe according to another example of Embodiment 4 of the present invention.
FIG. 9 is a cross-sectional view showing the structure of a conventional high-frequency probe.
[Explanation of symbols]
1 high frequency device, 8 device stage, 11 protruding substrate,
11a protruding substrate tip, 12 connector, 14 signal line, 16 elastic body,
18 Reinforced metal plate, 19 Insulating material, 20 Solid ground surface,
21 Signal protruding electrodes as signal electrodes,
22 Ground protruding electrode as ground electrode,
23a, 23b through holes, 24 electrode pads as signal electrodes,
25 Ground electrode film as ground electrode part, 26 Notch part,
27 Slit, 28 Insulating film, 29 Contact terminal, 30 Strain gauge,
31, 31a Laser displacement meter.

Claims

In a high-frequency probe that contacts a signal electrode and a ground electrode of a high-frequency device that is an object to be measured, and transmits a high-frequency signal to an external measuring instrument through a signal transmission path and a connector connected to the terminal end thereof
The signal line serving as the signal transmission path is covered with a flexible insulating material, and a protruding substrate made of the insulating material is provided so as to protrude from the high-frequency probe main body. The signal electrode part of the device, the signal electrode part in contact with the ground electrode, and the microstrip structure in which the ground electrode part is arranged on the surface of the protruding substrate tip part,
The signal electrode portion and the ground electrode portion are connected to the signal line and the ground surface through through holes provided in the protruding substrate, respectively.
A reinforcing metal plate is provided on the ground surface on the back surface of the protruding substrate via an elastic body having a predetermined thickness disposed at the tip, and the signal electrode portion on the surface of the protruding substrate is provided at the tip of the protruding substrate. The high- frequency probe is characterized in that the elastic body absorbs the bending of the protruding substrate that occurs when the ground electrode portion is simultaneously brought into contact with the signal electrode and the ground electrode of the high-frequency device .

RF probe according to claim 1, characterized in that a strain gauge consisting of a resistor for detecting a strain of the reinforcing metal plate reinforcing metal plate.

On the opposite side of the protruding substrate of reinforcing the metal plate, the laser displacement meter for detecting a displacement of the reinforcing metal plate tip, the high-frequency probe according to claim 1, characterized in that provided by spaced apart from the reinforcing metal plate.

The high-frequency probe according to any one of claims 1 to 3, wherein the signal electrode portion and the ground electrode portion are constituted by protruding electrodes.

The high-frequency probe according to any one of claims 1 to 3, wherein the ground electrode portion is formed on the entire surface of the protruding substrate excluding the signal electrode portion constituted by the protruding electrode and the surrounding area.

6. The high-frequency probe according to claim 4 , wherein the surface of the protruding electrode formed on the protruding substrate surface is coated with a metal film that does not have a Vickers hardness (Hv) of 40.

6. The high-frequency probe according to claim 4 , wherein a contact terminal made of a metal material is provided in the through hole so as to protrude from the surface of the protruding substrate, and a protruding electrode is constituted by the contact terminal.

A slit penetrating from the front surface to the ground surface on the back surface is provided at the tip of the protruding substrate, and a signal electrode portion is arranged on one surface divided by the slit, and is formed on the surface of the signal electrode portion and the other piece. The high frequency probe according to claim 1, wherein a ground electrode portion is in contact with the signal electrode and the ground electrode of a high frequency device, respectively.

9. The high frequency probe according to claim 8 , wherein the signal line is disposed at a predetermined distance from the slit.

The device stage electrically connected to the ground electrode of the high frequency device is used as a ground electrode of the high frequency device, and a ground electrode portion formed on the protruding substrate is brought into contact with the device stage . The high-frequency probe according to any one of the above.

11. The high-frequency probe according to claim 1, wherein the protruding substrate has an iso-stress structure in which a width gradually increases toward a main body side of the high-frequency probe.