JP4157919B2 - Method and apparatus for measuring thickness of glass layer - Google Patents
Method and apparatus for measuring thickness of glass layer Download PDFInfo
- Publication number
- JP4157919B2 JP4157919B2 JP2003059338A JP2003059338A JP4157919B2 JP 4157919 B2 JP4157919 B2 JP 4157919B2 JP 2003059338 A JP2003059338 A JP 2003059338A JP 2003059338 A JP2003059338 A JP 2003059338A JP 4157919 B2 JP4157919 B2 JP 4157919B2
- Authority
- JP
- Japan
- Prior art keywords
- glass layer
- layer
- glass
- light
- luminescent
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Description
【０００１】
【発明の属する技術分野】
本発明は、紫外線に対して発光性のガラス層と非発光性のガラス層とが積層したガラス材、例えば、合成石英ガラス層と天然石英ガラス層が積層した構造を有する石英ガラスルツボについて、合成石英ガラス層または天然石英ガラス層の層厚を非破壊的にかつ容易に測定することができる方法と装置に関する。
【０００２】
【従来の技術】
シリコン単結晶引き上げ用石英ガラスルツボとして、内層部が合成石英ガラス（合成層と云う）であって外層部が天然石英を溶融したガラス（天然層と云う）によって形成されたものが多く使用されている。このガラス層の層厚を測定する幾つかの方法が従来知られている。例えば、少量のシリコンを混入した酸素欠陥型石英ガラス粉末を予め合成層と天然層の境界部分に導入してルツボを形成し、この酸素欠陥型ガラス層が着色されることを利用し、光学顕微鏡等を用いて透明な合成石英ガラス層を通じて着色層の存在位置を検出し、合成層表面から着色層までの距離を測定して合成石英ガラス層の層厚を求める方法が知られている（特開２０００−１６８９６号公報）しかし、この方法は石英ガラスルツボの合成層と天然層の境界に予め着色層を形成しなければならない問題がある。
【０００３】
また、合成石英ガラス層と天然石英の溶融石英ガラス層とは紫外線の透過率が異なることを利用した測定方法が知られている。すなわち合成層は天然層よりも紫外線透過率が高く、一方、天然層は特定波長を吸収して紫外線の強度を減衰させる。従って、ガラス層全体の透過率は天然層の層厚に強く支配される。この現象を利用し、受光強度から特定の計算式によってガラス層の層厚を求める方法が知られている（特開２０００−１４６５３３号公報）。しかし、この方法は予め合成層と天然層の紫外線透過率を測定しておく必要があり、しかも異なる種類のガラス層に対しては汎用性がない。また、気泡を含有した不透明層の存在や、外表面の散乱によって透過率が大きく異なるので、精度が低いと云う問題がある。
【０００４】
この他に、酸素欠陥型石英ガラスは２４５nm波長の紫外線を照射すると青色に発光する現象（特定波長の吸収）を利用し、この紫外線による発光がないガラス層を形成することによって、シリコン単結晶引き上げ時の転位発生を抑制したルツボが知られている（特願２０００−１０３６９４号公報）。しかし、この方法は紫外線による発光を利用して酸素欠陥のないガラス層を形成するものであり、ガラス層の層厚測定とは異なる。
【０００５】
【発明が解決しようとする課題】
本発明は、従来の測定方法における上記問題を解決したものであり、例えば、合成石英ガラス層と天然石英ガラス層とを有する石英ガラスルツボについて、そのガラス層の層厚を非破壊的にかつ容易に測定することができる方法と装置を提供する。
【０００６】
【課題を解決する手段】
本発明は、以下の[１]または[２]に示す構成からなるガラス層の層厚測定方法に関する。
〔１〕紫外線に対して発光性のガラス層と非発光性のガラス層とを積層したガラス材について、該ガラス材に紫外線を照射し、非発光性ガラス層の表面反射光を検出して非発光性ガラス層の表面位置を検出し、さらに照射レンズの焦点をガラス層の層厚方向に移動して発光性ガラス層の発光開始位置を検出して非発光性ガラス層と発光性ガラス層の境界位置を検出し、上記表面位置から上記発光開始位置までの焦点移動距離から非発光性ガラス層の層厚を測定し、さらに照射レンズの焦点をガラス層の層厚方向に移動して発光消滅位置を検出し、上記発光開始位置から上記発光消滅位置までの焦点移動距離から発光性ガラス層の層厚を測定することを特徴とするガラス層の層厚測定方法。
〔２〕紫外線に対して発光性のガラス層と非発光性のガラス層とを積層したガラス材について、該ガラス材に紫外線を照射し、発光性ガラス層の発光開始を検出して発光性ガラス層の表面位置を検出し、さらに照射レンズの焦点をガラス層の層厚方向に移動して発光消滅位置を検出し、上記発光開始位置から上記発光消滅位置までの焦点移動距離から発光性ガラス層の層厚を測定し、さらに照射レンズの焦点をガラス層の層厚方向に移動して非発光性ガラス層の表面反射光を検出し、上記発光消滅位置から上記反射光検出位置までの焦点移動距離から非発光性ガラス層の層厚を測定することを特徴とするガラス層の層厚測定方法。
【０００７】
本発明の測定方法は、以下の[３]に示す態様を含む。
〔３〕紫外線に対して発光性のガラス層が天然石英ガラス層であって非発光性のガラス層が合成石英ガラス層であり、該ガラス材に紫外線を照射すると共に照射レンズの焦点をガラス層の層厚方向に移動し、合成ガラス層の反射光を検出して合成ガラス層の表面位置を検出し、また天然ガラス層の発光開始位置および発光消滅位置を検出し、この発光開始位置と発光消滅位置の焦点移動距離によって天然ガラス層の層厚を測定し、一方、上記表面位置から上記発光開始位置の焦点移動距離、または上記発光消滅位置から上記表面位置までの焦点移動距離によって合成ガラス層の層厚を測定する請求項１または請求項２に記載するガラス層の層厚測定方法。
【０００８】
また、本発明は以下の[４]に示す構成からなるガラス層の層厚測定装置に関する。
〔４〕紫外線に対して発光性のガラス層と非発光性のガラス層とを積層したガラス材について、該ガラス材に紫外線を照射する光学系と、非発光性ガラス層の表面反射光を検出する光学系と、発光性ガラス層の紫外線による発光を検出する光学系とを有する共焦点系光学測定手段を備え、上記照射光学系の照射レンズの焦点がガラス層の層厚方向に移動自在であり、反射光を検出して非発光性ガラス層の表面位置を検出し、また紫外線による発光開始位置および発光消滅位置を検出し、この発光開始位置と発光消滅位置の焦点移動距離によって発光性ガラス層の層厚を測定し、一方、上記表面位置から発光開始位置の焦点移動距離または発光消滅位置から上記表面位置までの焦点移動距離によって非発光性ガラス層の層厚を測定することを特徴とするガラス層の層厚測定装置。
【０００９】
【具体的な説明】
一般に天然溶融石英ガラス（以下、天然ガラスと云う）に紫外線を照射すると２４５nm波長の光を吸収して青紫色に発光する。この青紫色発光はガラス内部の酸素欠陥に起因すると云われている。一方、合成石英ガラス（以下、合成ガラスと云う）に紫外線を照射しても青紫色の発光は生じない。本発明の測定方法は、このような紫外線に対して発光性のガラス層と非発光性のガラス層を有するガラス材、具体的には、例えば外層部が天然溶融石英ガラス層(天然ガラス層)であって内層部が合成石英ガラス層(合成ガラス層)の石英ガラスルツボについて、そのガラス層の層厚を破壊せずに測定する方法である。
【００１０】
すなわち、本発明の測定方法は、例えば、外層部が天然ガラス層であって内層部が合成ガラス層の石英ガラスルツボについて、該石英ガラスルツボに紫外線を照射すると共に照射レンズの焦点をガラス層の層厚方向に移動し、反射光を検出して合成ガラス層の表面位置を検出し、また紫外線による発光を検出して天然ガラス部分を検出し、この検出位置に基づいて合成ガラス層の層厚を測定し、さらには、照射レンズの焦点を天然ガラス層の層厚方向に移動させ、紫外線発光の検出開始から検出終了までの間の焦点移動距離によって天然ガラス層の層厚を測定する測定方法である。
【００１１】
〔測定装置〕
本発明に係る測定装置の基本構成例を図１に示す。図示する測定装置は、測定対象のルツボ４０に紫外光を照射する光学系（照射系）１０、ルツボの合成ガラス層４１の表面反射光を検出する光学系（反射光検出系）２０、ルツボの天然ガラス層４２の発光を検出する光学系（発光検出系）３０を備えている。
【００１２】
照射系１０は光源１１、集光レンズ１２、ピンホール１３、フィルター１４、集光レンズ１５、照射レンズ１６によって形成されている。これらは光軸に沿って順に直列に配設されている。光源１１は例えば水銀キセノンランプなどが用いられる。光源１１から出た紫外光は集光レンズ１２によってピンホール１３に集光された後にフィルター１４を通過する。フィルター１４は紫外光を特定波長に単色化するバンドパスフィルターであり、単色化された紫外光は集光レンズ１５によって平行光にされ、照射レンズ１６を通じてルツボ４０に照射される。この照射レンズ１６は測定対象に向かって往復動自在に設置されており、照射光(254nm)の焦点位置を変えることができる。なお、天然ガラス層の発光吸収帯(２４５nm)を刺激するために照射光として２５４nm波長の紫外光を用いると良い。
【００１３】
反射光検出系２０は集光レンズ１５と照射レンズ１６の間に設置したハーフミラー１７とその側方に設けたハーフミラー２５、ハーフミラー２５の反射光を受ける集光レンズ２４、フィルター２３、ピンホール２２、受光管２１によって形成されている。発光検出系３０はハーフミラー２５を通過した発光を受ける集光レンズ３４、フィルター３３、ピンホール３２、受光管３１によって形成されている。上記フィルター２３は反射光(254nm)のみ通すフィルターであり、上記フィルター３３は発光波長(400nm)のみ通すフィルターである。さらに、これら照射系１０、反射検出系２０、および発光検出系３０は共焦点光学系である。すなわち、集光レンズ１２、２４、３４の各焦点は各々のピンホール１３、２２、３４に一致しており、集光レンズ２４および集光レンズ３４を通過した平行光がピンホール２２または３２を通じて受光管２１または３１に受光されるように形成されている。
【００１４】
〔測定方法〕
合成ガラス層４１と天然ガラス層４２が積層されたガラスルツボ４０に対して、合成ガラス層側から紫外光を照射する。ここで、照射レンズ１６の焦点がルツボ４０の手前にある場合（図１）、ルツボ４０の合成ガラス層表面で反射した反射光(254nm)はハーフミラー１７、２５によって反射されてレンズ２４で集光されるが、照射レンズ１６の焦点は合成ガラス層表面の手前にあるため、照射レンズ１６を通過する反射光は平行光にならず、ピンホール２３の手前で焦点を結ぶために反射光は受光管２１に殆ど入らない。同様に、天然ガラス層の発光(400nm)はハーフミラー１７で反射された後にミラー２５を通過してレンズ３４で集光されるが、照射レンズ１６を通過する発光は平行光にならず、ピンホール３２の手前で焦点を結ぶために受光管３１に殆ど入らない。
【００１５】
照射レンズ１６を移動して焦点が合成ガラス層の表面に一致した場合（図２）には、合成ガラス層表面で反射された反射光は照射レンズ１６を通過する際に平行光になり、ハーフミラー１７および２５を経由してレンズ２４に集光されたときにピンホール２２の位置で焦点を結び、ピンホール２２を通過して受光管２１に入光する。この反射光の検出によって合成ガラス層の表面位置が検出される。一方、天然ガラス層の発光(400nm)は、照射レンズ１６の焦点が合成ガラス層表面に一致しているため照射レンズ１６を通過する際に平行光にならず、ハーフミラー１７およびミラー２５を経由してレンズ３４を通過した際にピンホール３２の手前で焦点を結び、受光管３１に殆ど入らない。
【００１６】
さらに照射レンズを移動して焦点が天然ガラス層と合成ガラス層の界面に一致した場合（図３）、合成ガラス層表面で反射した反射光(254nm)は照射レンズ１６を通過する際に平行光にならず、従ってハーフミラー１７、２５を経由してレンズ２４で集光されたときにピンホール２３の奥で焦点を結ぶため、反射光は受光管２１に殆ど入らない。一方、天然ガラス層の発光(400nm)は照射レンズ１６をを通過する際に平行光になり、ハーフミラー１７および２５を経由してレンズ３４で集光された際にピンホール３２の位置に焦点を結ぶので、発光がピンホール３２を通過して受光管３１に入り検出される。この発光を検出することによって天然ガラス層と合成ガラス層の境界位置が検出される。
【００１７】
以上のようにして検出した合成ガラス層の表面位置および天然ガラス層との境界位置に基づき、照射レンズの焦点移動距離から合成ガラス層の層厚を求めることができる。また、照射レンズの焦点が天然ガラス層の層厚方向に移動している間は紫外線による天然ガラス部分の発光が検出されるが、照射レンズの焦点が天然ガラス層を外れるとこの発光は消滅するので、発光の検出開始から検出終了までの間に照射レンズの焦点が移動した距離によって天然ガラス層の層厚を測定することができる。
【００１８】
図１〜図３は、ガラスルツボの合成ガラス層側から紫外光を照射してガラス層の層厚を測定する手順を示しているが、天然ガラス層側から紫外光を照射した場合にも同様にしてガラス層の層厚を測定することができる。具体的には、照射レンズの焦点が天然ガラス層の表面位置に一致すると反射光ピークと天然ガラスの発光が検出される。また照射レンズの焦点が天然ガラス層の層厚方向に移動している間は紫外線による天然ガラス部分の発光が検出される。照射レンズの焦点が天然ガラス層を外れると天然ガラス部分の発光は消滅する。この反射光ピークと発光の検出開始から発光の検出終了までの間に照射レンズの焦点が移動した距離に基づいて天然ガラス層の層厚を測定することができる。引き続き、合成ガラス層内を照射レンズの焦点が移動する間は発光が検出されず、合成ガラス層の表面に達した時に表面反射の反射光ピークが検出されるので、天然ガラス層の発光の消滅から反射光ピークの検出までの間に照射レンズの焦点が移動した距離によって合成ガラス層の層厚を測定することができる。
【００１９】
なお、天然石英をアーク溶融して形成した溶融ガラス層はアーク側の表面層部分で紫外線発光を生じるので、アーク溶融して形成した石英ガラスルツボについても、外層側が天然ガラス層であって内層側が合成ガラス層によって形成された石英ガラスルツボについても、図１〜図３に示す手順に従ってガラス層の層厚を測定することができる。
【００２０】
【発明の実施の形態】
本発明を実施例によって具体的に示す。
〔実施例１〕
図４に示すように、測定台５０にガラスルツボ４０の開口を下向きにして載置し、測定装置６０を用いて合成ガラス層の層厚を測定した。測定装置６０は図１〜図３に示す照射光学系、反射光検出系、発光検出系を備えており、照射レンズ１６を通じて紫外光を合成ガラス層側から照射した。この結果を図５に示す。図５のグラフは合成ガラス層の層厚が異なる３種のルツボＡ、Ｂ、Ｃについて測定した結果である。Ｒは合成ガラス層の表面位置の検出ピークであり、プロファイル１、プロファイル２、プロファイル３はルツボＡ、Ｂ、Ｃの天然ガラス層の発光プロファイルである。この発光プロファイルに基づき、各ルツボについて照射レンズの移動距離に求め、この距離に石英ガラスの屈折率の係数を補正してルツボＡ、Ｂ、Ｃの合成ガラス層の層厚を求めた。このようにルツボＡ、Ｂ、Ｃの合成ガラス層の層厚を破壊せずに測定した後に、各ルツボを切断して断面サンプルを作成した。この断面サンプルに紫外線(254nm)を照射して断面写真を撮影し、合成ガラス層の層厚を実測した。これらの測定値を表１に対比して示した。合成ガラス層の層厚について、本発明に係る非破壊測定方法による測定値は断面サンプルによる実測値と良く一致する結果が得られた。
【００２１】
【表１】
〔実施例２〕
天然石英粉の上に合成石英の粉を敷き、真空加熱炉で溶解して厚さ６mmのガラス材を製造した。この方法で製造した天然石英ガラスは均一に酸素欠陥が入るため、紫外線を照射すると天然層全体が青紫色に発光する。このガラス材について本発明の図示する測定装置を用いて天然ガラス層の層厚を測定した。天然ガラス層側から紫外線を照射すると、図６に示すように、表面の反射光ピークＲ１が検出されるのと同時に、天然ガラスの青紫色の発光も検出される。照射レンズの焦点を動かしていき合成ガラス層に入ると天然ガラスの発光が検出されなくなる。更に焦点を動かすと、合成ガラス層側の表面から反射光のピークＲ２が検出される。天然ガラス層側の反射光ピークから合成ガラス層側の反射光ピークまでの焦点移動距離は４mmであり、石英ガラスの屈折率で補正すると６mmになり、ガラス材全体の厚さと一致する。このうち天然ガラス層の発光プロファイルが続く距離は２.８mmであり、石英ガラスの屈折率で補正すると４.２mmとなり、断面サンプルからもとめた厚さと一致した。
【００２３】
【発明の効果】
本発明の測定方法によれば、紫外線に対して発光性のガラス層と非発光性のガラス層を有するガラス材、例えば、外層部が天然ガラス層であって内層部が合成ガラス層の石英ガラスルツボについて、そのガラス層の層厚を破壊せずに精度よく測定することができる。
【図面の簡単な説明】
【図１】本発明の測定装置の構成例と測定手順を示す模式図。
【図２】本発明の測定装置の構成例と測定手順を示す模式図。
【図３】本発明の測定装置の構成例と測定手順を示す模式図。
【図４】石英ガラスルツボの層厚測定方法を示す概念図。
【図５】実施例１の測定結果を示すグラフ。
【図６】実施例２の測定結果を示すグラフ。
【符号の説明】
１０−照射系、１１−光源、１２−集光レンズ、１３−ピンホール、１４−フィルター、１５−集光レンズ、１６−照射レンズ、１７−ハーフミラー、２０−反射光検出系、２１−受光管、２２−ピンホール、２３−フィルター、２４−集光レンズ、２５−ハーフミラー、３０−発光検出系、３１−受光管、３２−ピンホール、３３−フィルター、３４−集光レンズ。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a glass material in which a glass layer that emits light with respect to ultraviolet rays and a glass layer that does not emit light are laminated, for example, a quartz glass crucible having a structure in which a synthetic quartz glass layer and a natural quartz glass layer are laminated. The present invention relates to a method and an apparatus capable of measuring the thickness of a quartz glass layer or a natural quartz glass layer nondestructively and easily.
[0002]
[Prior art]
As a quartz glass crucible for pulling up a silicon single crystal, a silica glass crucible having an inner layer portion made of synthetic quartz glass (referred to as a synthetic layer) and an outer layer portion formed of glass obtained by melting natural quartz (referred to as a natural layer) is often used. Yes. Several methods for measuring the thickness of the glass layer are conventionally known. For example, oxygen defect-type quartz glass powder mixed with a small amount of silicon is introduced into the boundary between the synthetic layer and the natural layer in advance to form a crucible, and this oxygen-defect-type glass layer is colored, using an optical microscope Is used to detect the position of the colored layer through a transparent synthetic quartz glass layer and measure the distance from the surface of the synthetic layer to the colored layer to obtain the layer thickness of the synthetic quartz glass layer (special However, this method has a problem that a colored layer must be formed in advance at the boundary between the synthetic layer and the natural layer of the quartz glass crucible.
[0003]
Further, a measurement method is known that utilizes the fact that the synthetic quartz glass layer and the fused silica glass layer of natural quartz have different ultraviolet transmittances. That is, the synthetic layer has a higher ultraviolet transmittance than the natural layer, while the natural layer absorbs a specific wavelength and attenuates the intensity of ultraviolet rays. Therefore, the transmittance of the entire glass layer is strongly controlled by the layer thickness of the natural layer. A method of using this phenomenon to determine the layer thickness of a glass layer from a received light intensity by a specific calculation formula is known (Japanese Patent Laid-Open No. 2000-146533). However, this method needs to measure the ultraviolet transmittance of the synthetic layer and the natural layer in advance, and is not versatile for different types of glass layers. In addition, the transmittance varies greatly depending on the presence of an opaque layer containing bubbles and the scattering of the outer surface, and there is a problem that the accuracy is low.
[0004]
In addition to this, oxygen-deficient quartz glass uses a phenomenon that emits blue light when irradiated with ultraviolet rays of 245 nm wavelength (absorption of specific wavelengths), and by forming a glass layer that does not emit light due to ultraviolet rays, the silicon single crystal is pulled up. A crucible that suppresses occurrence of dislocation at the time is known (Japanese Patent Application No. 2000-103694). However, this method forms a glass layer free from oxygen defects using light emission by ultraviolet rays, and is different from the measurement of the layer thickness of the glass layer.
[0005]
[Problems to be solved by the invention]
The present invention solves the above-mentioned problems in the conventional measuring method. For example, for a quartz glass crucible having a synthetic quartz glass layer and a natural quartz glass layer, the thickness of the glass layer is nondestructively and easily obtained. A method and apparatus that can be measured are provided.
[0006]
[Means for solving the problems]
The present invention relates to a method for measuring the thickness of a glass layer having the configuration shown in [1] or [2] below.
[1] With respect to a glass material in which a glass layer that is luminescent with respect to ultraviolet rays and a non-luminescent glass layer are laminated, the glass material is irradiated with ultraviolet rays, and the surface reflected light of the non-luminescent glass layer is detected and non-irradiated. The surface position of the luminescent glass layer is detected, and further, the focal point of the irradiation lens is moved in the layer thickness direction of the glass layer to detect the light emission start position of the luminescent glass layer, and the non-luminescent glass layer and the luminescent glass layer are detected. Detect the boundary position, measure the thickness of the non-luminous glass layer from the focal distance from the surface position to the light emission start position, and then move the focal point of the irradiation lens in the thickness direction of the glass layer to extinguish the light emission A method for measuring a layer thickness of a glass layer, comprising: detecting a position, and measuring a layer thickness of the luminescent glass layer from a focal movement distance from the light emission start position to the light emission extinction position.
[2] For a glass material obtained by laminating a glass layer that is luminescent with respect to ultraviolet rays and a glass layer that is not luminescent, the glass material is irradiated with ultraviolet rays to detect the start of light emission of the luminescent glass layer, thereby producing a luminescent glass. The surface position of the layer is detected, the focal point of the irradiation lens is further moved in the layer thickness direction of the glass layer to detect the light emission extinction position, and the light emitting glass layer is determined from the focal movement distance from the light emission start position to the light emission extinction position. Then, the focal point of the irradiation lens is moved in the layer thickness direction of the glass layer to detect the surface reflected light of the non-luminous glass layer, and the focus is moved from the emission extinction position to the reflected light detection position. A method for measuring the thickness of a glass layer, comprising measuring the thickness of a non-light-emitting glass layer from a distance.
[0007]
The measuring method of the present invention includes the embodiment shown in the following [3].
[3] The glass layer that emits light with respect to ultraviolet rays is a natural quartz glass layer, and the non-light emitting glass layer is a synthetic quartz glass layer. The glass material is irradiated with ultraviolet rays, and the focal point of the irradiation lens is the glass layer. The surface position of the synthetic glass layer is detected by detecting the reflected light of the synthetic glass layer, and the light emission start position and light emission extinction position of the natural glass layer are detected. The thickness of the natural glass layer is measured by the focal movement distance at the extinction position, while the synthetic glass layer is measured by the focal movement distance from the surface position to the emission start position or the focal movement distance from the emission extinction position to the surface position. The method for measuring a thickness of a glass layer according to claim 1 or 2, wherein the thickness of the glass layer is measured.
[0008]
The present invention also relates to a glass layer thickness measuring apparatus having the configuration shown in [4] below.
[4] For a glass material in which a glass layer that is luminescent with respect to ultraviolet rays and a glass layer that is not luminescent are laminated, an optical system for irradiating the glass material with ultraviolet rays and the surface reflected light of the non-luminescent glass layer are detected. And a confocal optical measuring means having an optical system for detecting light emitted by the ultraviolet rays of the luminescent glass layer, and the focal point of the irradiation lens of the irradiation optical system is movable in the layer thickness direction of the glass layer. Yes, the reflected light is detected to detect the surface position of the non-luminescent glass layer, and the emission start position and emission extinction position by ultraviolet light are detected, and the luminescent glass is detected by the focal distance of the emission start position and the emission extinction position. the layer thickness of the layer was measured, whereas, especially to measure the layer thickness of the non-luminescent glass layer by the focal movement distance of the focal distance traveled or emission disappearance position of the light emitting start position from said surface position to the surface position Layer thickness measuring apparatus for a glass layer to.
[0009]
[Specific explanation]
In general, when natural fused quartz glass (hereinafter referred to as natural glass) is irradiated with ultraviolet rays, it absorbs light of a wavelength of 245 nm and emits blue-violet light. This blue-violet emission is said to be caused by oxygen defects inside the glass. On the other hand, even if synthetic quartz glass (hereinafter referred to as synthetic glass) is irradiated with ultraviolet rays, blue-violet light emission does not occur. The measurement method of the present invention is a glass material having such a glass layer that is luminescent with respect to ultraviolet rays and a non-luminescent glass layer, specifically, for example, the outer layer portion is a natural fused quartz glass layer (natural glass layer). In this method, a quartz glass crucible whose inner layer portion is a synthetic quartz glass layer (synthetic glass layer) is a method of measuring the thickness of the glass layer without destroying it.
[0010]
That is, in the measurement method of the present invention, for example, for a quartz glass crucible whose outer layer portion is a natural glass layer and whose inner layer portion is a synthetic glass layer, the quartz glass crucible is irradiated with ultraviolet rays and the focal point of the irradiation lens is adjusted to the glass layer crucible. Move in the direction of the layer thickness, detect the reflected light to detect the surface position of the synthetic glass layer, detect the emission of ultraviolet light to detect the natural glass part, and based on this detection position the layer thickness of the synthetic glass layer And further measuring the layer thickness of the natural glass layer by moving the focal point of the irradiation lens in the layer thickness direction of the natural glass layer and moving the focal point from the detection start to the end of detection of ultraviolet light emission. It is.
[0011]
〔measuring device〕
An example of the basic configuration of a measuring apparatus according to the present invention is shown in FIG. The measuring apparatus shown in the figure includes an optical system (irradiation system) 10 that irradiates the crucible 40 to be measured with ultraviolet light, an optical system (reflected light detection system) 20 that detects surface reflection light of the synthetic glass layer 41 of the crucible, An optical system (luminescence detection system) 30 for detecting the luminescence of the natural glass layer 42 is provided.
[0012]
The irradiation system 10 includes a light source 11, a condenser lens 12, a pinhole 13, a filter 14, a condenser lens 15, and an irradiation lens 16. These are arranged in series along the optical axis. For example, a mercury xenon lamp is used as the light source 11. The ultraviolet light emitted from the light source 11 is condensed on the pinhole 13 by the condenser lens 12 and then passes through the filter 14. The filter 14 is a band-pass filter that monochromatically converts ultraviolet light to a specific wavelength. The monochromatic ultraviolet light is converted into parallel light by the condenser lens 15 and irradiated to the crucible 40 through the irradiation lens 16. This irradiation lens 16 is installed so as to be able to reciprocate toward the measurement object, and the focal position of the irradiation light (254 nm) can be changed. In addition, in order to stimulate the emission absorption band (245 nm) of the natural glass layer, it is preferable to use ultraviolet light having a wavelength of 254 nm as irradiation light.
[0013]
The reflected
[0014]
〔Measuring method〕
The glass crucible 40 in which the synthetic glass layer 41 and the natural glass layer 42 are laminated is irradiated with ultraviolet light from the synthetic glass layer side. Here, when the focal point of the irradiation lens 16 is in front of the crucible 40 (FIG. 1), the reflected light (254 nm) reflected by the surface of the synthetic glass layer of the crucible 40 is reflected by the half mirrors 17 and 25 and collected by the lens 24. However, since the focal point of the irradiation lens 16 is in front of the surface of the synthetic glass layer, the reflected light passing through the irradiation lens 16 does not become parallel light, and the reflected light is focused in front of the pinhole 23. It hardly enters the light receiving tube 21. Similarly, the light emitted from the natural glass layer (400 nm) is reflected by the half mirror 17 and then passes through the mirror 25 and is collected by the
[0015]
When the irradiation lens 16 is moved and the focal point coincides with the surface of the synthetic glass layer (FIG. 2), the reflected light reflected on the surface of the synthetic glass layer becomes parallel light when passing through the irradiation lens 16, and half When focused on the lens 24 via the mirrors 17 and 25, the focal point is focused at the position of the pinhole 22, and passes through the pinhole 22 and enters the light receiving tube 21. By detecting the reflected light, the surface position of the synthetic glass layer is detected. On the other hand, the light emission (400 nm) of the natural glass layer does not become parallel light when passing through the irradiation lens 16 because the focal point of the irradiation lens 16 coincides with the surface of the synthetic glass layer, and passes through the half mirror 17 and the mirror 25. Then, when passing through the
[0016]
Further, when the irradiation lens is moved and the focal point coincides with the interface between the natural glass layer and the synthetic glass layer (FIG. 3), the reflected light (254 nm) reflected by the surface of the synthetic glass layer is parallel light when passing through the irradiation lens 16. Therefore, when the light is condensed by the lens 24 via the half mirrors 17 and 25, the focal point is formed at the back of the pinhole 23, so that the reflected light hardly enters the light receiving tube 21. On the other hand, the light emitted from the natural glass layer (400 nm) becomes parallel light when passing through the irradiation lens 16 and is focused on the pinhole 32 when condensed by the
[0017]
Based on the surface position of the synthetic glass layer detected as described above and the boundary position with the natural glass layer, the layer thickness of the synthetic glass layer can be determined from the focal distance of the irradiation lens. Further, while the focal point of the irradiation lens is moving in the layer thickness direction of the natural glass layer, the light emission of the natural glass portion due to ultraviolet rays is detected, but this light emission disappears when the focal point of the irradiation lens is off the natural glass layer. Therefore, the layer thickness of the natural glass layer can be measured from the distance that the focal point of the irradiation lens has moved from the start of detection of light emission to the end of detection.
[0018]
1 to 3 show a procedure for measuring the layer thickness of a glass layer by irradiating ultraviolet light from the synthetic glass layer side of the glass crucible, but the same applies when irradiating ultraviolet light from the natural glass layer side. Thus, the layer thickness of the glass layer can be measured. Specifically, when the focal point of the irradiation lens coincides with the surface position of the natural glass layer, the reflected light peak and the natural glass emission are detected. Further, while the focal point of the irradiation lens moves in the layer thickness direction of the natural glass layer, light emission of the natural glass portion due to ultraviolet rays is detected. When the focal point of the irradiation lens deviates from the natural glass layer, the light emitted from the natural glass portion disappears. The layer thickness of the natural glass layer can be measured based on the reflected light peak and the distance that the focal point of the irradiation lens has moved between the start of detection of light emission and the end of detection of light emission. Subsequently, light emission is not detected while the focal point of the irradiation lens moves within the synthetic glass layer, and the reflected light peak of the surface reflection is detected when the surface of the synthetic glass layer is reached. The thickness of the synthetic glass layer can be measured based on the distance that the focal point of the irradiation lens has moved from when the reflected light peak is detected.
[0019]
In addition, since the molten glass layer formed by arc melting natural quartz produces ultraviolet light emission at the surface layer portion on the arc side, the quartz glass crucible formed by arc melting also has a natural glass layer on the outer layer side and an inner layer side on the inner layer side. Also about the quartz glass crucible formed of the synthetic glass layer, the layer thickness of the glass layer can be measured according to the procedure shown in FIGS.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is specifically illustrated by examples.
[Example 1]
As shown in FIG. 4, the glass crucible 40 was placed on the measuring table 50 with the opening facing downward, and the thickness of the synthetic glass layer was measured using the measuring device 60. The measuring device 60 includes an irradiation optical system, a reflected light detection system, and a light emission detection system shown in FIGS. 1 to 3, and irradiated ultraviolet light from the synthetic glass layer side through the irradiation lens 16. The result is shown in FIG. The graph of FIG. 5 shows the results of measurement for three types of crucibles A, B, and C having different synthetic glass layer thicknesses. R is a detection peak of the surface position of the synthetic glass layer, and profiles 1, 2, and 3 are emission profiles of the natural glass layers of the crucibles A, B, and C. Based on this light emission profile, the movement distance of the irradiation lens was determined for each crucible, and the refractive index coefficient of quartz glass was corrected to this distance to determine the thickness of the synthetic glass layers of crucibles A, B, and C. Thus, after measuring without destroying the layer thickness of the synthetic glass layer of crucible A, B, and C, each crucible was cut | disconnected and the cross-sectional sample was created. This cross-sectional sample was irradiated with ultraviolet rays (254 nm), a cross-sectional photograph was taken, and the thickness of the synthetic glass layer was measured. These measured values are shown in comparison with Table 1. With respect to the thickness of the synthetic glass layer, the measurement value obtained by the nondestructive measurement method according to the present invention was in good agreement with the actual measurement value obtained by the cross-sectional sample.
[0021]
[Table 1]
[Example 2]
Synthetic quartz powder was spread on natural quartz powder and melted in a vacuum heating furnace to produce a glass material having a thickness of 6 mm. Since natural quartz glass produced by this method has oxygen defects uniformly, the entire natural layer emits blue-violet light when irradiated with ultraviolet rays. About this glass material, the layer thickness of the natural glass layer was measured using the measuring apparatus which this invention shows in figure. When ultraviolet rays are irradiated from the natural glass layer side, as shown in FIG. 6, the reflected light peak R1 on the surface is detected, and at the same time, the blue-violet emission of natural glass is also detected. When the focal point of the irradiation lens is moved to enter the synthetic glass layer, light emission from the natural glass is not detected. When the focal point is further moved, the peak R2 of the reflected light is detected from the surface on the synthetic glass layer side. The focal distance from the reflected light peak on the natural glass layer side to the reflected light peak on the synthetic glass layer side is 4 mm, which is 6 mm when corrected by the refractive index of quartz glass, which is consistent with the thickness of the entire glass material. Of these, the distance that the emission profile of the natural glass layer continues was 2.8 mm, and when corrected by the refractive index of quartz glass, it was 4.2 mm, which was consistent with the thickness obtained from the cross-sectional sample.
[0023]
【The invention's effect】
According to the measurement method of the present invention, a glass material having a glass layer that is luminescent with respect to ultraviolet rays and a glass layer that is not luminescent, for example, quartz glass having an outer layer portion that is a natural glass layer and an inner layer portion that is a synthetic glass layer. About a crucible, it can measure accurately, without destroying the layer thickness of the glass layer.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a configuration example and a measurement procedure of a measurement apparatus according to the present invention.
FIG. 2 is a schematic diagram showing a configuration example and measurement procedure of the measurement apparatus of the present invention.
FIG. 3 is a schematic diagram showing a configuration example and a measurement procedure of the measurement apparatus of the present invention.
FIG. 4 is a conceptual diagram showing a method for measuring the layer thickness of a silica glass crucible.
5 is a graph showing measurement results of Example 1. FIG.
6 is a graph showing measurement results of Example 2. FIG.
[Explanation of symbols]
10-irradiation system, 11-light source, 12-condensing lens, 13-pinhole, 14-filter, 15-condensing lens, 16-irradiation lens, 17-half mirror, 20-reflected light detection system, 21-light reception Tube, 22-pinhole, 23-filter, 24-condensing lens, 25-half mirror, 30-luminescence detection system, 31-light-receiving tube, 32-pinhole, 33-filter, 34-condensing lens.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003059338A JP4157919B2 (en) | 2003-03-06 | 2003-03-06 | Method and apparatus for measuring thickness of glass layer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2003059338A JP4157919B2 (en) | 2003-03-06 | 2003-03-06 | Method and apparatus for measuring thickness of glass layer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2004271247A JP2004271247A (en) | 2004-09-30 |
| JP4157919B2 true JP4157919B2 (en) | 2008-10-01 |
Family
ID=33122174
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2003059338A Expired - Fee Related JP4157919B2 (en) | 2003-03-06 | 2003-03-06 | Method and apparatus for measuring thickness of glass layer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4157919B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9109879B2 (en) | 2012-02-29 | 2015-08-18 | Corning Incorporated | Systems for and methods of characterizing the thickness profile of laminated glass structures |
| US10295330B2 (en) | 2014-06-04 | 2019-05-21 | Corning Incorporated | Method and system for measuring thickness of glass article |
Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100997485B1 (en) | 2009-04-10 | 2010-12-01 | 수자원기술 주식회사 | Differential optical navigation sensor for mobile robots |
| JP5749149B2 (en) * | 2011-12-22 | 2015-07-15 | 株式会社Sumco | Method for measuring three-dimensional shape of silica glass crucible |
| CN104145051B (en) | 2011-12-22 | 2018-08-10 | 株式会社Sumco | The evaluation method of silica glass crucible, the manufacturing method of monocrystalline silicon |
| JP5749151B2 (en) * | 2011-12-22 | 2015-07-15 | 株式会社Sumco | Method for measuring the three-dimensional shape of the Raman spectrum of silica glass crucibles |
| JP5749152B2 (en) * | 2011-12-22 | 2015-07-15 | 株式会社Sumco | Method for measuring three-dimensional shape of surface roughness of silica glass crucible |
| JP5709737B2 (en) * | 2011-12-22 | 2015-04-30 | 株式会社Sumco | Method for producing silicon single crystal |
| JP5739797B2 (en) * | 2011-12-22 | 2015-06-24 | 株式会社Sumco | Method for producing silicon single crystal |
| JP5978343B2 (en) * | 2015-04-24 | 2016-08-24 | 株式会社Sumco | Method for producing silicon single crystal |
| JP6162848B2 (en) * | 2016-04-19 | 2017-07-12 | 株式会社Sumco | Method for producing silicon single crystal |
| JP6123001B2 (en) * | 2016-05-31 | 2017-04-26 | 株式会社Sumco | Method for evaluating silica glass crucible, method for producing silicon single crystal |
| CN110938871B (en) * | 2019-12-31 | 2024-05-31 | 江西中材新材料有限公司 | Polycrystalline silicon ingot casting equipment and polycrystalline silicon ingot casting method |
| CN117553700B (en) * | 2023-12-28 | 2024-04-02 | 成都电科星拓科技有限公司 | Method for detecting bending deformation and stress of sliding rod based on force-induced luminescent material |
-
2003
- 2003-03-06 JP JP2003059338A patent/JP4157919B2/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9109879B2 (en) | 2012-02-29 | 2015-08-18 | Corning Incorporated | Systems for and methods of characterizing the thickness profile of laminated glass structures |
| US9239231B2 (en) | 2012-02-29 | 2016-01-19 | Corning Incorporated | Systems for and methods of characterizing the thickness profile of laminated glass structures |
| US10295330B2 (en) | 2014-06-04 | 2019-05-21 | Corning Incorporated | Method and system for measuring thickness of glass article |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2004271247A (en) | 2004-09-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4157919B2 (en) | Method and apparatus for measuring thickness of glass layer | |
| KR101117826B1 (en) | Light-transmitting object examining method, manufacturing method for light-transmitting substrate of mask blank, manufacturing method for mask blank, manufacturing method for light-expososure mask, manufacturing method for semiconductor device and manufacturing method for phase shift mask | |
| KR100316193B1 (en) | How to distinguish natural diamond and artificial diamond | |
| US10837770B2 (en) | Surface measurement by means of excited fluorescence | |
| JP2006201465A5 (en) | ||
| JP4688150B2 (en) | Mask blank glass substrate manufacturing method, mask blank manufacturing method, exposure mask manufacturing method, and defect inspection apparatus | |
| US20110057120A1 (en) | Apparatus for determining the element occupancy on a surface by means of fluorescence | |
| JP2008119714A (en) | Laser beam machining apparatus | |
| JP5673211B2 (en) | Optical specimen detector | |
| TW201738528A (en) | Crucible measurement device, crucible measurement method, and crucible production method | |
| JP6805637B2 (en) | Hematocrit value measuring method, hematocrit value measuring device, amount of substance to be measured, and amount of substance to be measured | |
| JP2005062515A (en) | Fluorescence microscope | |
| JP2000221009A (en) | Device and method for measuring thickness of glass material | |
| US7688444B2 (en) | Method of determining laser stabilities of optical materials, crystals selected according to said method, and uses of said selected crystals | |
| JP2007225400A (en) | Optical detector | |
| JP2000111317A (en) | Measuring device/method for glass material thickness | |
| TW201738414A (en) | Silica glass crucible and method for producing silica glass crucible | |
| JP2019113492A (en) | Level difference measurement method and level difference measurement device | |
| JP2007121452A (en) | Method for manufacturing glass substrate for mask blank, method for manufacturing mask blank, method for manufacturing exposure mask, and method for manufacturing glass member for lithography | |
| JP2003084202A (en) | Ultraviolet-area fluorescent microscope, fluorescent material identifying method, and cleaning degree evaluating method | |
| JP2004271220A (en) | Evaluation apparatus and method of fused quartz | |
| JP2003131116A5 (en) | ||
| JP5359876B2 (en) | Workpiece defect inspection apparatus and optical member manufacturing method using the same | |
| JP6954116B2 (en) | Measuring method, measuring device and measuring chip | |
| JP2000146533A (en) | Instrument and method for measuring thickness of light- transmission body |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20060303 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20071108 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20071120 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080117 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080219 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080314 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20080513 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20080527 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 4157919 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110725 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110725 Year of fee payment: 3 |
|
| RD02 | Notification of acceptance of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: R3D02 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110725 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110725 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120725 Year of fee payment: 4 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120725 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120725 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130725 Year of fee payment: 5 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130725 Year of fee payment: 5 |
|
| S111 | Request for change of ownership or part of ownership |
Free format text: JAPANESE INTERMEDIATE CODE: R313111 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130725 Year of fee payment: 5 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| LAPS | Cancellation because of no payment of annual fees |