JP4581135B2 - Chip for optical waveguide mode sensor - Google Patents
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/55—Specular reflectivity
- G01N21/552—Attenuated total reflection
- G01N21/553—Attenuated total reflection and using surface plasmons
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Description
本発明は、光導波モードを利用することによって、被検出試料の検出高感度化を図ることができる光導波モードセンサーに関する。 The present invention relates to an optical waveguide mode sensor capable of increasing detection sensitivity of a sample to be detected by using an optical waveguide mode.
一般に、DNA、抗原−抗体などのたんぱく質、糖鎖などのバイオセンサー及び金属イオン、有機分子などの化学物質センサーとして、表面プラズモン共鳴（SPR）のモードを用いる技術が知られている。
この技術は、ガラス上に貴金属（金・銀など）を蒸着し、そのガラスの金属を蒸着した面と反対側の面を、屈折率調節オイルを介して光学プリズムと密着させた構造からなり、レーザー光あるいは白色光を、プリズムを通してガラスに照射し、その反射光の強度を検出するものである。In general, a technique using a surface plasmon resonance (SPR) mode is known as a biosensor such as a protein such as DNA or an antigen-antibody, a sugar chain, or a chemical substance sensor such as a metal ion or an organic molecule.
This technology consists of a structure in which a noble metal (gold, silver, etc.) is vapor-deposited on the glass, and the surface opposite to the surface on which the metal of the glass is vapor-deposited is in close contact with an optical prism via refractive index adjusting oil. Laser light or white light is applied to the glass through the prism, and the intensity of the reflected light is detected.
入射光はガラスに対して全反射となる条件で入射され、金属の表面側の界面に染み出すエバネセント波によって、ある入射角で表面プラズモン共鳴が発現する。表面プラズモン共鳴が起こると、エバネセント波は表面プラズモンによって吸収されるので、その入射角付近では反射光の強度が著しく減少する。表面プラズモン共鳴が発現する入射角や反射光強度は、金属の表面上の付着物の厚さ、誘電率によって変化することから、金属の表面上に被検出試料と結合あるいは吸着する物質を修飾し、被検出試料が結合あるいは吸着した際に生じる入射角や反射率強度の変化を検出し、被検出試料の結合量（膜厚あるいは質量）に換算するというものである。 Incident light is incident on the glass under the condition of total reflection, and surface plasmon resonance appears at a certain incident angle by the evanescent wave that oozes out to the interface on the metal surface side. When surface plasmon resonance occurs, the evanescent wave is absorbed by the surface plasmon, so that the intensity of the reflected light is remarkably reduced in the vicinity of the incident angle. The incident angle and reflected light intensity at which surface plasmon resonance appears change depending on the thickness of the deposit on the metal surface and the dielectric constant. Therefore, the substance that binds to or adsorbs the sample to be detected is modified on the metal surface. The change in the incident angle and the reflectance intensity that occurs when the sample to be detected is bound or adsorbed is detected and converted into the amount of binding (film thickness or mass) of the sample to be detected.
このような技術に関連する例として、被分析試料が流れる溶液流路の、その表面が臨む分子認識機能膜と、この分子認識機能膜の裏面に設けた金属薄膜と、この金属薄膜側から白色のｐ偏光・平行光を入射させる励起光源と、入射光が金属薄膜表面で反射することによって発生する反射光を受光する干渉計を用いたフーリエ変換分光器を備えた光センサーが開示されている（特許文献１参照）。
また、光ビームを誘電体ブロックと金属膜との界面で収束させる表面プラズモンセンサーにおいて、光利用効率を高くし、表面プラズモン共鳴を高感度で測定できるように、反射角が異なる成分が一方向に連なる向きにライン状に集光するシリンドリカルレンズを設けた技術が開示されている（特許文献２参照）。As an example related to such a technique, a molecular recognition function film facing the surface of a solution flow path through which an analyte sample flows, a metal thin film provided on the back surface of the molecular recognition function film, and a white color from the metal thin film side An optical sensor having a Fourier transform spectrometer using an excitation light source that makes p-polarized / parallel light incident thereon and an interferometer that receives reflected light generated by reflection of incident light on the surface of the metal thin film is disclosed. (See Patent Document 1).
In addition, in a surface plasmon sensor that converges the light beam at the interface between the dielectric block and the metal film, components with different reflection angles are unidirectional so that light utilization efficiency can be increased and surface plasmon resonance can be measured with high sensitivity. A technique in which a cylindrical lens for condensing light in a line shape in a continuous direction is disclosed (see Patent Document 2).
しかし、上記の表面プラズモン共鳴のモードを用いる従来の技術では、サイズの小さい被検出試料を検出する場合、感度が不十分であるという問題がある。したがって、サイズが小さい被検出試料を検出するためには、サイズの大きい分子あるいは誘電率の大きい分子を被検出試料にラベル化するなどの工程が必要であり、精度が劣るだけでなく、工程が煩雑になるという不利な点がある。
本発明は、上記の問題点を解決することを目的とし、従来の表面プラズモン共鳴を利用する技術よりも、高い感度で小さいサイズの被検出試料をラベルフリーで検出できる光導波モードセンサーを提供する。 The present invention aims to solve the above-described problems, and provides an optical waveguide mode sensor capable of detecting a sample to be detected with a higher sensitivity and a smaller size than a technique using conventional surface plasmon resonance. .
課題を解決するための手段は次のとおりである。
（１）ガラス基板とその上に被覆したＳｉからなる反射膜と、さらに該反射膜上に形成した光導波路を構成する誘電体層とからなるチップであって、
該基板側から入射された光が該光導波路内を伝搬する状態となる角度で光を該基板面に入射させ、該基板面側へ出射される反射光の強度の変化を読み取ることによって、該光導波路表面に吸着又は付着した物質の検出を行う光導波モードセンサー用のチップ。
（２）前記誘電体層の表面に分子認識基を化学修飾したことを特徴とする（１）記載の光導波モードセンサー用のチップ。
（３）前記基板側から入射された光は、p偏光又はs偏光であることを特徴とする（１）又は（２）記載の光導波モードセンサー用のチップ。
（４）前記ガラス基板面に、屈折率調節オイルを介して光学プリズムを密着させた構造を備えていることを特徴とする（１）〜（３）のいずれかに記載の光導波モードセンサー用のチップ。
本発明の光導波モードセンサーは、透明な誘電体材料又は透明な伝導体材料の基板とその上に被覆した反射膜と、さらに該反射膜上に形成した誘電体層とからなるチップを用いる。このチップの基板側から、前記反射膜に光を入射する光入射機構と、反射膜によって反射される前記光の反射光を検出する光検出機構と、を備え、入射光の一部又は全部が前記誘電体層からなる光導波路内を伝搬する光導波モードと結合することによって反射光強度が減少する光入射角度領域を用いて、前記誘電体層の表面に検出対象となる物質が吸着又は付着した際に生じる入射角度或いは反射光強度の変化を読み取ることによって、物質の検出を行う。
Means for solving the problems are as follows.
(1) A chip comprising a glass substrate, a reflective film made of Si coated thereon, and a dielectric layer constituting an optical waveguide formed on the reflective film,
By making the light incident on the substrate surface at an angle at which the light incident from the substrate side propagates in the optical waveguide, and reading the change in the intensity of the reflected light emitted to the substrate surface side, A chip for an optical waveguide mode sensor that detects a substance adsorbed or adhered to the surface of the optical waveguide.
(2) The chip for an optical waveguide mode sensor according to (1), wherein a molecular recognition group is chemically modified on the surface of the dielectric layer.
(3) The optical waveguide mode sensor chip according to (1) or (2), wherein the light incident from the substrate side is p-polarized light or s-polarized light.
(4) The optical waveguide mode sensor according to any one of (1) to (3), wherein the glass substrate surface is provided with a structure in which an optical prism is brought into close contact with a refractive index adjusting oil. Chips.
The optical waveguide mode sensor of the present invention uses a chip comprising a substrate of a transparent dielectric material or a transparent conductor material, a reflective film coated thereon, and a dielectric layer formed on the reflective film. A light incident mechanism that makes light incident on the reflective film from the substrate side of the chip, and a light detection mechanism that detects reflected light of the light reflected by the reflective film, and a part or all of the incident light is A substance to be detected is adsorbed or adhered to the surface of the dielectric layer using a light incident angle region in which the reflected light intensity decreases by coupling with an optical waveguide mode propagating in the optical waveguide made of the dielectric layer. The substance is detected by reading the change in the incident angle or reflected light intensity generated at the time.
前記反射膜は元素の周期表の４〜１４族の金属又はこれらの金属を基とする合金から選択した一成分以上の金属薄膜である。基板上に形成する金属又は合金薄膜の材料は、元素の周期表の４〜１４族から選択したものであれば、特に制限はないが、センサーの安定性を考慮すると、基板への密着性が高い材料を用いることが望ましい。金属の薄膜を被覆する手段としては、蒸着、スパッタリング、無電解めっき、電気めっき法などが利用でき、基板に被覆できる手段であれば、特に制限はない。
前記反射膜は半導体材料の薄膜にすることができる。基板上に形成する半導体材料は、特に制限はないが、センサーの安定性を考慮すると、基板への密着性が高い材料を用いることが望ましい。半導体材料の薄膜を被覆する手段としては、蒸着、スパッタリング、分子線エピタキシ（ＭＢＥ）などが利用でき、基板に被覆できる手段であれば、特に制限はない。The reflective film is a metal thin film having one or more components selected from metals of groups 4 to 14 of the periodic table of elements or alloys based on these metals. The material of the metal or alloy thin film to be formed on the substrate is not particularly limited as long as it is selected from Group 4 to 14 of the periodic table of elements. However, in consideration of the stability of the sensor, the adhesion to the substrate is low. It is desirable to use a high material. As a means for coating the metal thin film, there is no particular limitation as long as it can be applied to the substrate by vapor deposition, sputtering, electroless plating, electroplating, and the like.
The reflective film can be a thin film of a semiconductor material. The semiconductor material formed on the substrate is not particularly limited, but it is desirable to use a material having high adhesion to the substrate in consideration of the stability of the sensor. The means for coating the thin film of semiconductor material is not particularly limited as long as vapor deposition, sputtering, molecular beam epitaxy (MBE), and the like can be used and the substrate can be coated.
前記光導波モードセンサーは、前記誘電体層からなる光導波路の２次の光導波モードを利用して検出を行う。前記誘電体層は２次の光導波モードが発現する程度の膜厚を有している。
記誘電体層は酸化シリコン、ポリメチルメタクリル酸を主成分とするポリマー、金属酸化物、金属窒化物、半導体材料の酸化物、又は半導体材料の窒化物を主成分として形成されている。前記誘電体層の表面に分子認識基を化学修飾したチップを用いる。
前記分子認識基として、−NH2、−COOH、−SCN、スクシンイミド基、ビオチニル基のいずれかを化学修飾したチップを用いる。上記分子認識基の使用は、いずれも好ましいものであり、特に制限なく使用することができる。前記基板上に形成された誘電体層とは反対側の面から照射されたp偏光又はs偏光の反射光を検出する。The optical waveguide mode sensor performs detection using a secondary optical waveguide mode of an optical waveguide made of the dielectric layer. The dielectric layer has a thickness such that a secondary optical waveguide mode is exhibited.
The dielectric layer is formed mainly of silicon oxide, a polymer mainly composed of polymethylmethacrylic acid, a metal oxide, a metal nitride, an oxide of a semiconductor material, or a nitride of a semiconductor material. A chip having a molecular recognition group chemically modified on the surface of the dielectric layer is used.
As the molecular recognition group, a chip in which any of —NH 2 , —COOH, —SCN, succinimide group, and biotinyl group is chemically modified is used. Use of the above-mentioned molecular recognition group is preferable, and can be used without any particular limitation. P-polarized light or s-polarized light reflected from the surface opposite to the dielectric layer formed on the substrate is detected.
光学プリズムに、前記基板の前記誘電体層が形成されている面と反対側の面を、屈折率調節オイルを介して密着させた構造を備えている。ｐ偏光又はｓ偏光の光が光学プリズムの中心軸に対してある角度で入射したときに発現する光導波モードのうち、前記誘電体層の厚さを厚くするときに最初に発生する１次または２番目に発生する２次の光導波モードと入射光との結合が生じる入射角度付近に入射角度を固定し、反射光の強度を検出する。
前記誘電体層の表面に化学修飾された分子認識基に、気体中又は液体中において、選択的に吸着あるいは化学結合する分子、イオン又は分子集合体の膜厚、質量又は誘電率を測定する。
また、本発明の光導波モードセンサー用チップは、光導波モードセンサーに使用され、基板上に反射膜を被覆し、さらにその反射膜の上に誘電体の光導波路を持つ。前記反射膜は元素の周期表の４〜１４族の金属又はこれらの金属を基とする合金から選択した一成分以上の薄膜である。基板上に形成する金属又は合金薄膜の材料は、元素の周期表の４〜１４族から選択したものであれば、特に制限はないが、センサーの安定性を考慮すると、基板への密着性が高い材料を用いることが望ましい。金属の薄膜を被覆する手段としては、蒸着、スパッタリング、無電解めっき、電気めっき法などが利用でき、基板に被覆できる手段であれば、特に制限はない。前記反射膜は半導体材料の薄膜である。基板上に形成する半導体材料は、特に制限はないが、センサーの安定性を考慮すると、基板への密着性が高い材料を用いることが望ましい。半導体材料の薄膜を被覆する手段としては、蒸着、スパッタリング、分子線エピタキシ（ＭＢＥ）などが利用でき、基板に被覆できる手段であれば、特に制限はない。The optical prism has a structure in which the surface of the substrate opposite to the surface on which the dielectric layer is formed is in close contact with a refractive index adjusting oil. Of the optical waveguide modes that appear when p-polarized light or s-polarized light is incident at an angle with respect to the central axis of the optical prism, the first order generated when the thickness of the dielectric layer is increased or The incident angle is fixed near the incident angle at which the coupling between the second-order optical waveguide mode generated second and the incident light occurs, and the intensity of the reflected light is detected.
The film thickness, mass, or dielectric constant of a molecule, ion, or molecular assembly selectively adsorbed or chemically bonded to a molecular recognition group chemically modified on the surface of the dielectric layer in a gas or liquid is measured.
The optical waveguide mode sensor chip of the present invention is used for an optical waveguide mode sensor, and a substrate is coated with a reflective film, and a dielectric optical waveguide is formed on the reflective film. The reflective film is a thin film of one or more components selected from metals of groups 4 to 14 of the periodic table of elements or alloys based on these metals. The material of the metal or alloy thin film to be formed on the substrate is not particularly limited as long as it is selected from Group 4 to 14 of the periodic table of elements. However, in consideration of the stability of the sensor, the adhesion to the substrate is low. It is desirable to use a high material. As a means for coating the metal thin film, there is no particular limitation as long as it can be applied to the substrate by vapor deposition, sputtering, electroless plating, electroplating, and the like. The reflective film is a thin film of a semiconductor material. The semiconductor material formed on the substrate is not particularly limited, but it is desirable to use a material having high adhesion to the substrate in consideration of the stability of the sensor. The means for coating the thin film of semiconductor material is not particularly limited as long as vapor deposition, sputtering, molecular beam epitaxy (MBE), and the like can be used and the substrate can be coated.
本発明によれば、従来の表面プラズモン共鳴を利用する技術よりも、高い感度で小さいサイズの被検出試料をラベルフリーで検出できる。また、反射膜として、基板に対して密着性の高い金属や半導体材料を用いることによって、長期的な信頼性が高く、安定なセンサーを提供することができる。さらに、２次の光導波モードを利用することによって、被検出試料の検出高感度化を図ることができるという優れた効果を有する。従来の表面プラズモン共鳴を利用する技術よりも、高い感度でかつ小さいサイズの被検出試料を、ラベルを使用することなく検出できるという著しい効果を有する。 According to the present invention, it is possible to detect a sample to be detected with a higher sensitivity and a smaller size than a technique using conventional surface plasmon resonance. Further, by using a metal or a semiconductor material having high adhesion to the substrate as the reflective film, a long-term reliability and a stable sensor can be provided. Furthermore, by using the secondary optical waveguide mode, there is an excellent effect that the detection sensitivity of the detected sample can be increased. Compared with the conventional technique using surface plasmon resonance, it has a remarkable effect that it is possible to detect a sample to be detected with high sensitivity and a small size without using a label.
以下、本発明の特徴を、図等を用いて具体的に説明する。なお、以下の説明は、本願発明の理解を容易にするためのものであり、これに制限されるものではない。すなわち、本願発明の技術思想に基づく変形、実施態様、他の例は、本願発明に含まれるものである。
本発明は、上記の通り、感度を向上させるために、光導波モードを利用する。まず、光導波モードについて説明する。本発明では、図１に示すようなチップを用いる。このチップは、ガラス基板とその上に被覆した反射膜と、さらに該反射膜上に形成した誘電体層とから構成される。この誘電体層が光導波路となって、特定の条件の下で入射光の一部又は全部をこの誘電体層からなる光導波路内を伝搬させる。このような構造を持つチップに対して、ガラス側から光を入射すると、ある入射角において反射光が極端に減少し、ディップが現れる、と言う現象が生じる。このような例を図２に示す。なお、ガラス基板を用いた場合を例として以下説明するが、基板材質としては、ガラス以外にも、プラスチック(樹脂)、セラミックス、絶縁物等の透明な誘電体材料、或いは、ITO等の透明な伝導体材料を用いることができる。Hereinafter, the features of the present invention will be specifically described with reference to the drawings. In addition, the following description is for making an understanding of this invention easy, and is not restrict | limited to this. That is, modifications, embodiments, and other examples based on the technical idea of the present invention are included in the present invention.
As described above, the present invention uses an optical waveguide mode in order to improve sensitivity. First, the optical waveguide mode will be described. In the present invention, a chip as shown in FIG. 1 is used. This chip is composed of a glass substrate, a reflective film coated thereon, and a dielectric layer formed on the reflective film. This dielectric layer becomes an optical waveguide, and part or all of the incident light is propagated in the optical waveguide made of this dielectric layer under specific conditions. When light is incident on the chip having such a structure from the glass side, a phenomenon occurs in which reflected light is extremely reduced and a dip appears at a certain incident angle. Such an example is shown in FIG. In addition, although the case where a glass substrate is used will be described below as an example, the substrate material is not only glass but also a transparent dielectric material such as plastic (resin), ceramics, insulator, or transparent material such as ITO. Conductor materials can be used.
図２は、図１のチップのガラス側にプリズムを配して、光を入射した際の、光の入射角度と反射光強度の関係を示す。このような反射光強度の減少の原因は主に２つある。１つは、前述のような表面プラズモン共鳴であり、図２中のθ0の入射角度で生じる反射光強度のディップがこの表面プラズモン共鳴に起因するものである。表面プラズモン共鳴は、負の誘電率を持つ金属、特に貴金属などを反射膜として用いた場合に生じる現象であり、図１に示す誘電体光導波路部分が無くても生じる現象である。また、この表面プラズモン共鳴に起因する反射光の減少は入射光がｐ偏光の場合には生じるがｓ偏光の場合は生じない。FIG. 2 shows the relationship between the incident angle of light and the intensity of reflected light when a prism is disposed on the glass side of the chip of FIG. There are mainly two reasons for such a decrease in reflected light intensity. One is surface plasmon resonance as described above, and a dip in reflected light intensity generated at an incident angle of θ 0 in FIG. 2 is caused by this surface plasmon resonance. The surface plasmon resonance is a phenomenon that occurs when a metal having a negative dielectric constant, particularly a noble metal, is used as a reflective film, and is a phenomenon that occurs even without the dielectric optical waveguide portion shown in FIG. Further, the decrease in the reflected light due to the surface plasmon resonance occurs when the incident light is p-polarized light but does not occur when the incident light is s-polarized light.
もう１つの反射光強度の減少が光導波モードに起因するものであり、図２中のθm=1、2、3の入射角での反射光強度のディップに対応する。この反射光強度のディップは図１に示す誘電体層、つまり誘電体光導波路が無い場合や薄い場合は生じない。光導波モードが発生する誘電体層の最低の厚さは、使用する光の偏光状態によっても異なるが、一般に誘電体層の屈折率が高ければ薄くても良く、光の波長が短い場合も薄くて良い。一方、誘電体の屈折率が低い場合や使用する光の波長が長い場合は、厚い誘電体層が要求される。例えば、誘電体層の屈折率が1.457で波長633nmの光を用いた時、光がｓ偏光の場合は誘電体層の厚さは最低100nm程度が必要であり、ｐ偏光の場合は200nm程度以上の厚さが必要である。Another decrease in reflected light intensity is caused by the optical waveguide mode, and corresponds to a dip in reflected light intensity at incident angles of θ m = 1 , 2 , and 3 in FIG. This reflected light intensity dip does not occur when the dielectric layer shown in FIG. 1, that is, when the dielectric optical waveguide is not present or thin. The minimum thickness of the dielectric layer in which the optical waveguide mode occurs varies depending on the polarization state of the light used, but in general, it may be thin if the refractive index of the dielectric layer is high, and thin even if the wavelength of light is short. Good. On the other hand, a thick dielectric layer is required when the refractive index of the dielectric is low or when the wavelength of light used is long. For example, when light having a refractive index of 1.457 and a wavelength of 633 nm is used, if the light is s-polarized light, the thickness of the dielectric layer must be at least about 100 nm, and if p-polarized light is about 200 nm or more Thickness is required.
本発明では、この光導波モードに起因する、特定入射角度における急激な反射光強度の減少、つまりディップが生じる現象を用いて、この誘電体光導波路層表面への分子の吸着、接触、結合を検出する。
光導波モードとは、ある有限の空間内に光が閉じこめられて伝搬していく状態のことである。最も良く知られている光導波モードとしては光ファイバ内の光の伝搬状態が挙げられる。光ファイバは、屈折率が低いファイバ状(通常非常に細長い円筒型)の材料の中心に屈折率の高い部位(通常、コアと呼ばれる)を形成し、この屈折率差によって生じる光の反射によって、光をコア中に閉じこめて伝搬させる。
屈折率の低い物質(空気や真空状態も含む)に挟まれた板状の材料中を光が伝搬するスラブ型光導波路も良く知られている。In the present invention, by using the phenomenon in which the reflected light intensity suddenly decreases at a specific incident angle due to the optical waveguide mode, that is, a dip occurs, the adsorption, contact, and bonding of molecules to the surface of the dielectric optical waveguide layer are performed. To detect.
The optical waveguide mode is a state in which light is confined and propagated in a certain finite space. The most well-known optical waveguide mode is the propagation state of light in the optical fiber. An optical fiber forms a high refractive index portion (usually called a core) at the center of a fiber-like (usually very long cylindrical) material having a low refractive index, and reflection of light caused by this refractive index difference Light is confined in the core and propagated.
A slab type optical waveguide in which light propagates through a plate-like material sandwiched between substances having a low refractive index (including air and vacuum conditions) is also well known.
本発明で用いるチップの構造は図１に示すように、基体となるガラスの上に反射膜を形成し、さらにその上に、誘電体の層を形成する。この誘電体の層の上側(表面側)が、この誘電体よりも屈折率の低い物質、例えば空気や水、に触れている場合、この誘電体層はスラブ導波路と似た構造となり、この誘電体層中に光を閉じこめて伝搬させることが可能となる。このように、この誘電体層中に光が閉じこめられて伝搬する状態が、この場合の光導波モードである。 As shown in FIG. 1, the structure of a chip used in the present invention is formed by forming a reflective film on a glass serving as a substrate and further forming a dielectric layer thereon. When the upper side (surface side) of this dielectric layer is in contact with a material having a refractive index lower than that of the dielectric, such as air or water, the dielectric layer has a structure similar to a slab waveguide. Light can be confined and propagated in the dielectric layer. Thus, the state where light is confined and propagated in the dielectric layer is the optical waveguide mode in this case.
図１におけるガラス側から光を入射した際、反射膜がある程度薄い場合、全反射条件を満たす入射角で光を照射した場合でも、その光の一部又は全部がエバネッセント波として、誘電体層側に染み出す。光の入射角がある特定の値となったとき、このエバネセント波は誘電体層中を伝搬する光となる。このことを、入射光が光導波モードと結合する、又は入射光が光導波モードとなる、と表現する。その結果、入射された光は、その一部又は全部が、誘電体光導波路内を伝搬する光となり、その結果、反射されなくなる。よって、前述のような反射光強度の減少が起こる。この反射光強度の減少は、ある波長の光に対して、ある特定の入射角付近でのみ生じ、図２に示すようなディップ形状となる。 When light is incident from the glass side in FIG. 1, if the reflective film is thin to some extent, even if light is irradiated at an incident angle satisfying the total reflection condition, a part or all of the light is converted into an evanescent wave, and the dielectric layer side Ooze out. When the incident angle of light reaches a certain value, the evanescent wave becomes light propagating in the dielectric layer. This is expressed as the incident light is combined with the optical waveguide mode, or the incident light is in the optical waveguide mode. As a result, part or all of the incident light becomes light propagating in the dielectric optical waveguide, and as a result, is not reflected. Therefore, the reflected light intensity is reduced as described above. This decrease in reflected light intensity occurs only near a specific incident angle with respect to light of a certain wavelength, resulting in a dip shape as shown in FIG.
光導波モードは伝搬する光の波長、偏光面、誘電体光導波路となるべき膜の厚さに依存し、個数が増減する。
上述のように、誘電体光導波路の厚さが非常に薄いと、光導波モードは発生しない。この厚さが厚くなると光導波モードが発生するのだが、まず初めに発生する光導波モードを１次の光導波モード、さらに膜厚を厚くしていくと、次に発生する光導波モードを２次の光導波モード、と言うように呼ぶ。さらに膜厚を厚くしていくと、３次、４次と光導波モードが増えていく。
よって、誘電体光導波路の厚さを厚くしていくと、まず、1次の光導波モードと入射光との結合による反射光強度の減少が観測され、さらに厚さを増していくと、２次の光導波モードと入射光との結合による反射光強度の減少が観測され、さらに厚さが厚くなると、さらに高次の光導波モードとの結合による反射光強度の減少が見られるようになる。The number of optical waveguide modes increases or decreases depending on the wavelength of propagating light, the plane of polarization, and the thickness of the film to be a dielectric optical waveguide.
As described above, when the thickness of the dielectric optical waveguide is very thin, the optical waveguide mode does not occur. When this thickness is increased, an optical waveguide mode is generated. First, an optical waveguide mode generated first is a primary optical waveguide mode, and when the film thickness is further increased, an optical waveguide mode generated next is 2. It is called as the next optical waveguide mode. As the film thickness is further increased, the third-order, fourth-order, and optical waveguide modes increase.
Therefore, when the thickness of the dielectric optical waveguide is increased, first, a decrease in the reflected light intensity due to the coupling between the primary optical waveguide mode and the incident light is observed, and when the thickness is further increased, 2 A decrease in reflected light intensity due to the coupling between the next optical waveguide mode and the incident light is observed. As the thickness further increases, a decrease in the reflected light intensity due to coupling with the higher-order optical waveguide mode is observed. .
前述のように、図１に示す基板構造を持つチップのガラス側から、光を入射すると、ある角度で、入射光と光導波モードとの結合によって、反射光強度が著しく減少する。この角度や反射光強度は、誘電体光導波路の表面の誘電率変化に大きく依存する為、誘電体光導波路表面に物質の吸着、付着等が生じると、この角度や反射光強度に変化が生じる。この変化を読み取ることによって、特定物質の有無及び、その物質の量などを検出するのが、光導波モードセンサーである。また、本センサーは、光導波路表面に薄い膜を形成した際、その膜の厚さや屈折率、誘電率を測定することも可能であることから、薄膜の物性評価用センサーとしても使用可能である。 As described above, when light is incident from the glass side of the chip having the substrate structure shown in FIG. 1, the intensity of the reflected light is remarkably reduced due to the coupling between the incident light and the optical waveguide mode at a certain angle. Since this angle and reflected light intensity greatly depend on the change in the dielectric constant of the surface of the dielectric optical waveguide, if the adsorption or adhesion of a substance occurs on the surface of the dielectric optical waveguide, this angle or reflected light intensity changes. . The optical waveguide mode sensor detects the presence or absence of a specific substance and the amount of the substance by reading this change. In addition, when a thin film is formed on the surface of the optical waveguide, this sensor can also measure the thickness, refractive index, and dielectric constant of the film, so it can also be used as a sensor for evaluating physical properties of thin films. .
図２に示すKretschmann配置（プリズムとガラスおよび反射膜が密着した状態の構造）と呼ばれる配置は、既存の表面プラズモン共鳴の光学系で利用されている。但し、本発明の光導波モードセンサーには、反射膜表面に誘電体層が付加されている。光が、偏光板及びプリズムを介して、ガラス側から反射膜に光を照射すると、特定の条件の下でこの誘電体層による光導波路（誘電体光導波路）の光導波モードと入射光との結合が生じる。つまり入射光が光導波モードとなる。この光導波モードと入射光との結合によって、入射光の一部又は全部をこの誘電体光導波路内を伝搬させて、反射されなくすることによって、反射光強度の減少が起こる。反射膜によって反射される光強度の減少は、検出器によって検出される。偏光板は図３に示すように２枚用いられることが多く、2枚の偏光板のうち、プリズムに近い方の偏光板は、反射面に対して振動方向が平行なp偏光あるいは垂直なs偏光の選択を行う為に設置されている。また、レーザー光源に近い方の偏光板は、光導波路に入射される光強度を調節するために設置されている。
このように、光導波モードによる反射光強度の減少も、従来のKretschmann配置と同様の光学系にて観測することが可能である。よって、本発明ではこの光学系を利用する。光学プリズムは図中に示した三角プリズム以外に、シリンドリカルプリズムや半球プリズムなど、あらゆるプリズムが使用可能である。また、光学プリズムを用いなくても光導波モードを発現させることは可能である。光学プリズムは、光導波モードと入射光との結合が生じる光の入射角度を変化させる働きをする。An arrangement called a Kretschmann arrangement (a structure in which a prism, glass, and a reflection film are in close contact) shown in FIG. 2 is used in an existing surface plasmon resonance optical system. However, the optical waveguide mode sensor of the present invention has a dielectric layer added to the surface of the reflective film. When light irradiates the reflective film from the glass side through the polarizing plate and the prism, the optical waveguide mode (dielectric optical waveguide) of the optical waveguide (dielectric optical waveguide) by this dielectric layer and the incident light under specific conditions Bonding occurs. That is, incident light becomes an optical waveguide mode. The coupling between the optical waveguide mode and the incident light causes a part or all of the incident light to propagate through the dielectric optical waveguide so that it is not reflected, thereby reducing the reflected light intensity. The decrease in light intensity reflected by the reflective film is detected by the detector. As shown in FIG. 3, two polarizing plates are often used. Of the two polarizing plates, the polarizing plate closer to the prism is p-polarized light whose vibration direction is parallel to the reflecting surface or vertical s. Installed to select polarization. The polarizing plate closer to the laser light source is installed to adjust the light intensity incident on the optical waveguide.
Thus, the decrease in reflected light intensity due to the optical waveguide mode can also be observed with an optical system similar to the conventional Kretschmann arrangement. Therefore, this optical system is used in the present invention. As the optical prism, in addition to the triangular prism shown in the drawing, any prism such as a cylindrical prism or a hemispherical prism can be used. Further, it is possible to develop the optical waveguide mode without using an optical prism. The optical prism functions to change the incident angle of light that causes coupling between the optical waveguide mode and incident light.
図３は光導波モードセンサーシステムの構成例であり、通常、レーザー光源、偏光子、ゴニオメーター、光検出器、解析用ソフトウエアを備える。液セルとチップ及びプリズムを組み合わせたものを、入射角制御用ゴニオメーター上に設置し、偏光板を通してp又はs偏光されたレーザー光をプリズム側から入射する。これに対する反射光を光検出器で取り込む。液セルは、チップの分子検出面、つまり誘電体層の表面に検体となる溶液を保持するために用いる。チョッパーとロックインアンプはレーザー光以外の外光（室内光など）からのノイズを抑えるために用いることがある。 FIG. 3 shows a configuration example of an optical waveguide mode sensor system, which normally includes a laser light source, a polarizer, a goniometer, a photodetector, and analysis software. A combination of a liquid cell, a chip and a prism is placed on an incident angle control goniometer, and p- or s-polarized laser light is incident from the prism side through a polarizing plate. The reflected light is captured by the photodetector. The liquid cell is used to hold a solution serving as an analyte on the molecular detection surface of the chip, that is, the surface of the dielectric layer. Choppers and lock-in amplifiers are sometimes used to suppress noise from outside light (such as room light) other than laser light.
基板に用いるガラスは、通常、検出時に用いる光に対しての屈折率が1.4〜2.2程度が望ましく、さらには1.6〜2.0程度が望ましい。誘電体光導波路は、基本的には検出に用いる光に対して透明な材料であればどのような材料でもよい。この誘電体光導波路に酸化シリコンを利用する場合には、反射膜上への堆積が容易であり、光学的に平滑な表面を得ることができ、また生体関連物質に対して不活性であり、さらに表面の化学修飾が容易であるという特徴があるので、好ましい材料と言える。酸化シリコンの堆積方法としては、ゾルゲル法、熱酸化法、スパッタリング法などを使用することができる。 In general, the glass used for the substrate preferably has a refractive index of about 1.4 to 2.2, more preferably about 1.6 to 2.0 with respect to light used for detection. The dielectric optical waveguide may basically be any material as long as it is transparent to the light used for detection. When silicon oxide is used for this dielectric optical waveguide, it can be easily deposited on the reflective film, an optically smooth surface can be obtained, and it is inert to biological materials. Furthermore, it can be said to be a preferable material because it has a feature that chemical modification of the surface is easy. As a silicon oxide deposition method, a sol-gel method, a thermal oxidation method, a sputtering method, or the like can be used.
また、ポリマー材料、例えば、ポリメチルメタクリル酸を主成分として形成されるポリマーも、酸化シリコンと同様の効果を持ち、望ましい材料といえる。また、窒化シリコンのような半導体材料の窒化物、酸化チタンのような金属酸化物、窒化アルミニウムのような金属窒化物など、透明度の高い誘電体材料は好ましい材料である。検出に用いる光は、基本的には電磁波であれば特に制限はないが、取り扱いが容易という点で、赤外〜紫外領域の光を使うことが望ましい。
反射膜には、化学的且つ物理的に安定な金属の薄膜や、半導体材料薄膜であれば、どのような材料でも使用可能である。よって、金属材料としては、元素の周期表の４〜１４族から選択した金属、またはこのような金属を主として用いた合金であれば、特に制限はない。また、半導体材料は、ＳｉやＧｅのような１種類の元素による半導体以外に、２種類以上の元素で構成された化合物半導体でも良い。また、半導体は、p型、n型、真性半導体のいずれでも良い。但し、検出に用いる光の偏光状態によっては、反射膜としての材料を適切に選択しなければ高感度が得られない場合がある。光の偏光状態にはｐ偏光とｓ偏光とがある。本センサーでは、図２において、電界の振動方向がy方向に垂直な光がｐ偏光、電界の振動方向がy方向に水平な光がｓ偏光である。In addition, a polymer material such as a polymer formed mainly of polymethylmethacrylic acid has the same effect as silicon oxide and can be said to be a desirable material. In addition, a highly transparent dielectric material such as a nitride of a semiconductor material such as silicon nitride, a metal oxide such as titanium oxide, or a metal nitride such as aluminum nitride is a preferable material. The light used for detection is basically not particularly limited as long as it is an electromagnetic wave, but it is desirable to use light in the infrared to ultraviolet region because it is easy to handle.
Any material can be used for the reflective film as long as it is a chemically and physically stable metal thin film or a semiconductor material thin film. Therefore, the metal material is not particularly limited as long as it is a metal selected from Groups 4 to 14 of the periodic table of elements or an alloy mainly using such a metal. Further, the semiconductor material may be a compound semiconductor composed of two or more elements other than a semiconductor composed of one kind of element such as Si or Ge. The semiconductor may be any of p-type, n-type, and intrinsic semiconductor. However, depending on the polarization state of light used for detection, high sensitivity may not be obtained unless a material for the reflective film is appropriately selected. The polarization state of light includes p-polarized light and s-polarized light. In this sensor, in FIG. 2, the light whose electric field vibration direction is perpendicular to the y direction is p-polarized light, and the light whose electric field vibration direction is horizontal to the y direction is s-polarized light.
本センサーは、入射光と光導波モードとの結合によって反射光強度が著しく減少する角度を入射光角度θaとすると、このθa付近に光の入射角度を設定し、誘電体光導波路の表面に検出対象となる物質が吸着又は付着した際に生じる、この入射角度θaの変化や反射光強度の変化を読み取ることによって、物質を検出する。θaは例えば図２に示すθm=1、θm=2、θm=3のような角度である。よって、θa付近での反射光強度の減少量が大きければ大きいほど、θaの変化又は反射光強度の変化が読み取りやすく、センサーの感度が向上する。このことから、全反射時の反射光強度を１とすると、角度θaにおける反射光強度の変化の度合い、つまり、角度θa付近での反射率の減少量ΔRが少なくとも0.1以上が望ましく、また、0.3程度以上であることがより望ましい。また、材料によっては、反射光強度が全体的に低くなってしまい、特定な入射角において反射光強度が著しく減少する、と言う現象自身が明確に現れないものもある。このような測定感度の低下は反射膜として用いる材料の屈折率ｎと減衰係数ｋに依存する。上記のような理由の為に、ｐ偏光に対して高感度が期待できないｎとｋの範囲を図１２に、ｓ偏光に対して高感度が期待できないｎとｋの範囲を図１３に示す。よって、この領域外のｎとｋを持つ材料を反射膜として用いることが望ましいThis sensor sets the incident angle of light near this θa and detects it on the surface of the dielectric optical waveguide, where the incident light angle θa is the angle at which the reflected light intensity decreases significantly due to the coupling between the incident light and the optical waveguide mode. The substance is detected by reading the change in the incident angle θa and the change in the reflected light intensity that occur when the target substance is adsorbed or adhered. θa is an angle such as θ m = 1 , θ m = 2 , θ m = 3 shown in FIG. Therefore, the greater the amount of decrease in reflected light intensity near θa, the easier it is to read changes in θa or reflected light intensity, and the sensitivity of the sensor improves. For this reason, assuming that the reflected light intensity at the time of total reflection is 1, the degree of change in reflected light intensity at the angle θa, that is, the reduction amount ΔR in the vicinity of the angle θa is preferably at least 0.1 or more, and 0.3 It is more desirable to be at least. Also, depending on the material, the reflected light intensity is generally lowered, and the phenomenon that the reflected light intensity significantly decreases at a specific incident angle does not appear clearly. Such a decrease in measurement sensitivity depends on the refractive index n and the attenuation coefficient k of the material used as the reflective film. For the above reasons, FIG. 12 shows the range of n and k where high sensitivity cannot be expected for p-polarized light, and FIG. 13 shows the range of n and k where high sensitivity cannot be expected for s-polarized light. Therefore, it is desirable to use a material having n and k outside this region as the reflective film.
但し、一般に物質のｎとｋは光の波長によって変化する。よって、同じ材料でも、検出に用いる光によって、感度が良くなったり悪くなったりする。例えばp偏光を用いる際、銀を反射膜に用いた場合、光の波長が４００ｎｍの時、nとkは、それぞれ0.173と1.95である。よって、図１２に示した高感度が期待できない領域外となる。一方、光の波長が３００ｎｍの場合、nとkは、それぞれ1.522と0.992となってしまい、図１２に示した高感度が期待できない領域内になってしまう。
この銀の場合の反射光強度と入射角との関係をフレネルの法則に基づくフレネルの式を用いて計算した結果を図１４に示す。ここでは、入射光はｐ偏光であり、図２に示したように、頂点が90°の三角プリズムを介して入射され、ガラスの屈折率は1.8として計算した。誘電体光導波路膜の屈折率と厚さ及び銀薄膜の厚さは、波長300ｎｍの光に対してはそれぞれ1.488、600nm、17nm、波長400ｎｍに対してはそれぞれ1.470、750nm、33nmとした。また、誘電体光導波路の表面は水に浸されているとした。図１４からも明らかなように、銀を反射膜として用いた場合、波長400ｎｍでは鋭いディップが観測され、高感度が期待できるが、波300ｎｍでは、ディップが浅く、また幅も広いため、高感度は期待できない。However, generally n and k of a substance change with the wavelength of light. Therefore, even with the same material, the sensitivity may be improved or deteriorated depending on the light used for detection. For example, when p-polarized light is used and silver is used for the reflective film, n and k are 0.173 and 1.95, respectively, when the wavelength of light is 400 nm. Therefore, it is outside the region where high sensitivity shown in FIG. 12 cannot be expected. On the other hand, when the wavelength of light is 300 nm, n and k are 1.522 and 0.992, respectively, and are in the region where high sensitivity shown in FIG. 12 cannot be expected.
FIG. 14 shows the result of calculating the relationship between the reflected light intensity and the incident angle in the case of silver using the Fresnel equation based on Fresnel's law. Here, the incident light is p-polarized light and is incident through a triangular prism having a vertex of 90 ° as shown in FIG. 2, and the refractive index of glass is calculated as 1.8. The refractive index and thickness of the dielectric optical waveguide film and the thickness of the silver thin film were 1.488, 600 nm, and 17 nm for light with a wavelength of 300 nm, and 1.470, 750 nm, and 33 nm for wavelength 400 nm, respectively. In addition, the surface of the dielectric optical waveguide is immersed in water. As is clear from FIG. 14, when silver is used as the reflective film, a sharp dip is observed at a wavelength of 400 nm and high sensitivity can be expected. However, at a wave of 300 nm, the dip is shallow and the width is wide. Cannot be expected.
図１２に見られるように、ｐ偏光に対しては、高感度が期待できない領域が、ｋが小さい領域側に寄っている。一般に金属は赤外〜紫外領域でｋが大きいので、ｐ偏光を用いた場合には殆どの金属を反射膜として用いることができる。一方、ｓ偏光を用いた場合、図１３に見られるように、高感度が期待できない領域が、ｋが大きい領域にも及んでいる。よって、ｓ偏光を用いた場合、使用可能な材料が制限されてしまう。
しかし、ｓ偏光を用いた場合の方がｐ偏光を用いた場合よりディップの幅が狭い場合がある。その例を図１５に示す。図１５は、波長633ｎｍの光を用い、屈折率1.8のガラス上に厚さ31nmのCuを反射膜として形成し、その上に厚さ1.1μｍの酸化シリコン(屈折率1.457)を形成した際のシミュレーション結果である。ここでも、入射光は図２に示したように、頂点が90°の三角プリズムを介して入射され、誘電体光導波路の表面は水に浸されているとした。図１５では、点線がｓ偏光に対するシミュレーション結果であり、実線がｐ偏光に対するシミュレーション結果である。As can be seen in FIG. 12, for p-polarized light, the region where high sensitivity cannot be expected is closer to the region where k is small. In general, since metal has a large k in the infrared to ultraviolet region, almost any metal can be used as the reflective film when p-polarized light is used. On the other hand, when s-polarized light is used, a region where high sensitivity cannot be expected extends to a region where k is large, as shown in FIG. Therefore, when s-polarized light is used, usable materials are limited.
However, the dip width may be narrower when s-polarized light is used than when p-polarized light is used. An example is shown in FIG. FIG. 15 shows a case in which light having a wavelength of 633 nm is used and a 31 nm-thick Cu is formed as a reflective film on a glass having a refractive index of 1.8, and a 1.1 μm-thick silicon oxide (refractive index of 1.457) is formed thereon. It is a simulation result. Here again, as shown in FIG. 2, the incident light is incident through a triangular prism having a vertex of 90 °, and the surface of the dielectric optical waveguide is immersed in water. In FIG. 15, the dotted line is the simulation result for s-polarized light, and the solid line is the simulation result for p-polarized light.
この図から分かるように、ｓ偏光を用いた場合の方がディップの幅が狭い。ここで、誘電体光導波路表面に検出対象分子が付着した際、ディップが生じる角度の変化量はｓ偏光、ｐ偏光ともに同程度であることから、ディップが狭いｓ偏光を用いた場合の方が、感度が良くなる。
また、ｓ偏光を用いる際には、ｎが大きくｋが小さい半導体材料を使用することも有効である。
以上のことから、反射膜としてどの材料を用いるかは、用いる光の波長、及びその波長に対する材料のｎ、ｋ、及びその材料によって得られる角度θaにおけるディップの深さや幅を考え、最適なものを選ぶことが望ましい。As can be seen from this figure, the dip width is narrower when s-polarized light is used. Here, when molecules to be detected are attached to the surface of the dielectric optical waveguide, the amount of change in the angle at which the dip occurs is about the same for both s-polarized light and p-polarized light, so the case where s-polarized light with a narrow dip is used. , Sensitivity is improved.
When using s-polarized light, it is also effective to use a semiconductor material having a large n and a small k.
From the above, the material to be used as the reflective film is optimal considering the wavelength of light to be used, the n and k of the material for that wavelength, and the depth and width of the dip at the angle θa obtained by that material. It is desirable to choose.
反射膜の厚さもディップの深さや幅に大きな影響を与える為、最適値を選択する必要がある。例えば、反射膜が厚すぎると光が光導波路に到達せず、ディップが現れなくなってしまう。また、反射膜の選択には、その反射膜の持つ他の特性、例えば、温度に対する安定性、ガラスとの密着性、なども重要である。ガラスと密着しにくい材料を用いる場合、例えば金や銀を反射膜として用いる場合、ガラスとの密着性を向上させるために、Ｃｒなどの接着層を間に挟むことが有効である。
しかし、高温で長時間使用する際などは、接着材料が金や銀内に拡散し、センサーとしての特性に変化が生じてしまう恐れもあるため、なるべく、接着層は使用しない方がよい。よって、こういった観点からは、ガラスとの密着性の高い材料を反射膜の材料として選択することが望ましい。Since the thickness of the reflective film also greatly affects the depth and width of the dip, it is necessary to select an optimum value. For example, if the reflective film is too thick, light does not reach the optical waveguide and dip does not appear. In selecting a reflective film, other characteristics of the reflective film, such as temperature stability and adhesion to glass, are also important. In the case of using a material that hardly adheres to glass, for example, when gold or silver is used as a reflective film, it is effective to sandwich an adhesive layer such as Cr in order to improve the adhesion to glass.
However, when used at a high temperature for a long time, the adhesive material may diffuse into gold or silver, and the characteristics as a sensor may change. Therefore, it is better not to use an adhesive layer as much as possible. Therefore, from such a viewpoint, it is desirable to select a material having high adhesion to glass as the material of the reflective film.
誘電体光導波路については、上述のようにその厚さや屈折率と発生する光導波モードとの間に大きな関係がある。屈折率1.479の酸化シリコンを光導波路に用いる場合の酸化シリコン層の膜厚と、反射光強度と光の入射角の関係を、図４（ｐ偏光）及び図５（ｓ偏光）に示す。ここでは、屈折率1.846のガラスと、反射膜として膜厚47nmの金を用い、照射光波長は633nmとした。また、誘電体層表面はリン酸緩衝液（ＰＢＳ緩衝液）に浸されているとした。図中の数字は、酸化シリコン層の厚さである。ｐ偏光では、酸化シリコンの膜厚が600nmのときには、１次の光導波モードとの結合によるディップが発現している。また、酸化シリコンの膜厚が900nmの時には、２次の導波モードとの結合によるディップの発現も確認できる。ｓ偏光では、酸化シリコンの膜厚が650nmのときには1次の光導波モードとの結合によるディップが発現しており、700nmおよび750nmの場合には2次の光導波モードとの結合によるディップの発現が観測されている。 As described above, there is a large relationship between the thickness and refractive index of the dielectric optical waveguide and the generated optical waveguide mode. FIG. 4 (p-polarized light) and FIG. 5 (s-polarized light) show the relationship between the thickness of the silicon oxide layer, the reflected light intensity, and the incident angle of light when silicon oxide having a refractive index of 1.479 is used for the optical waveguide. Here, glass with a refractive index of 1.846 and gold with a thickness of 47 nm were used as the reflective film, and the irradiation light wavelength was 633 nm. Further, the surface of the dielectric layer is assumed to be immersed in a phosphate buffer solution (PBS buffer solution). The number in the figure is the thickness of the silicon oxide layer. In p-polarized light, when the silicon oxide film has a thickness of 600 nm, a dip due to the coupling with the primary optical waveguide mode appears. In addition, when the silicon oxide film has a thickness of 900 nm, the appearance of a dip due to the coupling with the secondary waveguide mode can be confirmed. In s-polarized light, a dip due to the coupling with the primary optical waveguide mode appears when the silicon oxide film thickness is 650 nm, and the dip due to the coupling with the secondary optical waveguide mode occurs at 700 nm and 750 nm. Has been observed.
酸化シリコンにより形成された光導波路表面に物質が吸着した際に予想される反射率変化量の見積（酸化シリコン760nm）を図６に示す。これは、リン酸緩衝液中で屈折率1.45のたんぱく質が膜厚5nmで吸着すると仮定したものである。
図６の左は、従来型の表面プラズモン共鳴（SPR）モードによるディップを利用したもの、右はs偏光の2次の光導波モードとの結合によるディップを利用したものを示す。SPRモード用いた場合、最大で0.15の変化量が期待されるのに対し、ｓ偏光の2次の光導波モードとの結合によるディップを利用した場合、最大で0.62の変化量が期待される。よって、光導波モードを利用することによって高感度化が期待できる。FIG. 6 shows an estimate of the reflectance change amount (silicon oxide 760 nm) that is expected when a substance is adsorbed on the surface of the optical waveguide formed of silicon oxide. This is based on the assumption that a protein with a refractive index of 1.45 is adsorbed at a film thickness of 5 nm in a phosphate buffer.
The left of FIG. 6 shows a dip using a conventional surface plasmon resonance (SPR) mode, and the right shows a dip using a s-polarized second-order optical waveguide mode. When the SPR mode is used, a maximum amount of change of 0.15 is expected, whereas when a dip due to the coupling of s-polarized light with the second-order optical waveguide mode is used, a maximum amount of change of 0.62 is expected. Therefore, high sensitivity can be expected by using the optical waveguide mode.
光導波モードとの結合によるディップは、反射光強度が減少する入射角の範囲、つまりディップの幅、が表面プラズモン共鳴の場合と比較して、非常に狭いのが特徴である。よって光導波路表面に被検出試料が吸着あるいは結合すると、反射光強度が減少する入射角が大きく変化する。
図６で示したように、２次の光導波モードとの結合によるディップが起こる角度に入射角を固定した場合に得られる反射率変化量は、表面プラズモン共鳴を利用する場合と比較して、理論的に４倍程度大きい。従って、従来の表面プラズモン共鳴を利用する技術よりも高い感度で小さいサイズの被検出試料をラベルフリーで検出できる。The dip due to the coupling with the optical waveguide mode is characterized in that the range of the incident angle where the reflected light intensity decreases, that is, the width of the dip, is very narrow compared to the case of surface plasmon resonance. Therefore, when the sample to be detected is adsorbed or bonded to the surface of the optical waveguide, the incident angle at which the reflected light intensity decreases greatly changes.
As shown in FIG. 6, the reflectance change amount obtained when the incident angle is fixed at the angle at which the dip due to the coupling with the second-order optical waveguide mode occurs is compared with the case where surface plasmon resonance is used. Theoretically about 4 times larger. Therefore, it is possible to detect a sample to be detected with a higher sensitivity and a smaller size than conventional techniques using surface plasmon resonance without labeling.
また、図７に示すように、１次の光導波モードとの結合によるディップに比べ、2次の光導波モードとの結合によるディップは反射光強度が減少する入射角範囲が広い。図７で示す楔形の曲線部分において、1次の光導波モードにおける半値幅が0.03°であるのに対し、2次の光導波モードでは0.08°と見積もられる。したがって、2次の光導波モードは、1次の光導波モードに比べ、入射角の制御が容易であるという著しい特徴を有する。
一方、感度は1次および2次の光導波モードにおいてほぼ同等であるため、被検出試料の検出における2次の光導波モードの利用は、1次の光導波モードに比べて優れている。Further, as shown in FIG. 7, the dip due to the coupling with the secondary optical waveguide mode has a wider incident angle range in which the reflected light intensity decreases than the dip due to the coupling with the primary optical waveguide mode. In the wedge-shaped curved portion shown in FIG. 7, the half-value width in the first-order optical waveguide mode is 0.03 °, whereas it is estimated to be 0.08 ° in the second-order optical waveguide mode. Therefore, the secondary optical waveguide mode has a remarkable feature that the incident angle can be easily controlled as compared with the primary optical waveguide mode.
On the other hand, since the sensitivity is almost the same in the primary and secondary optical waveguide modes, the use of the secondary optical waveguide mode in detection of the detected sample is superior to the primary optical waveguide mode.
屈折率1.846の板ガラスをガラス基板として用い、金を金属として用い、誘電体光導波路として酸化シリコンを用いた場合、フレネルの法則に基づくフレネルの式を用いて、2次の光導波モードとの結合によるディップが発現する酸化シリコン光導波路の膜厚を計算したところ、p偏光では900 nm以上、s偏光では700 nm以上であることが明らかとなった。そこで、25mm四方、厚さ1mm、屈折率1.846の板ガラスの片面にクロム(5 nm)、金（47 nm）、クロム（5 nm）の順で真空蒸着し、その上に酸化シリコンを760 nmスパッタリングすることによりチップを作製した。なお、ここでのクロムは、金とガラスとの接着強度の向上のために用いられた。 When a plate glass with a refractive index of 1.846 is used as the glass substrate, gold is used as the metal, and silicon oxide is used as the dielectric optical waveguide, coupling to the second-order optical waveguide mode using Fresnel's law based on Fresnel's law When the thickness of the silicon oxide optical waveguide in which the dip due to is calculated, it was found that it was 900 nm or more for p-polarized light and 700 nm or more for s-polarized light. Therefore, vacuum deposition was performed in the order of chromium (5 nm), gold (47 nm), and chromium (5 nm) on one side of a plate glass of 25 mm square, thickness 1 mm, refractive index 1.846, and silicon oxide was sputtered onto it at 760 nm. Thus, a chip was manufactured. In addition, the chromium here was used in order to improve the adhesive strength between gold and glass.
スパッタリングされた光導波路面が1/15Mリン酸緩衝液に接するようチップを液セルに装着し、光導波路面と反対側の面は屈折率調節オイルを介して光学プリズムと密着させた。これを入射角制御用ゴニオメーター上に装着し、s偏光されたヘリウム−ネオンレーザー(633 nm)を、光学プリズムを通してチップに照射した。
反射光強度は集光レンズを通してフォトダイオードで検出した。入射角を45°から60°まで変化させながら、反射光強度を測定したところ、図８に示すように57°付近に1次の光導波モード、48°付近に2次の光導波モードとの結合によるディップが検出された。The chip was mounted on the liquid cell so that the sputtered optical waveguide surface was in contact with the 1 / 15M phosphate buffer, and the surface opposite to the optical waveguide surface was brought into close contact with the optical prism via refractive index adjusting oil. This was mounted on an incident angle control goniometer, and an s-polarized helium-neon laser (633 nm) was irradiated onto the chip through an optical prism.
The reflected light intensity was detected with a photodiode through a condenser lens. The reflected light intensity was measured while changing the incident angle from 45 ° to 60 °. As shown in FIG. 8, the primary optical waveguide mode was observed at around 57 ° and the secondary optical waveguide mode was observed at around 48 °. A dip due to binding was detected.
次に、チップを弱アルカリ水溶液に一時間浸漬後乾燥し、0.2wt.% 3-アミノプロピルトリエトキシシランのエタノール溶液に2時間浸漬し、酸化シリコン表面に反応活性なアミノ基を修飾した。エタノールでリンスし乾燥後、0.1 mMスルホスクシンイミジル-N-(D-ビオチニル)-6-アミノヘキサネートを含む1/15Mリン酸緩衝液を液セル中に注入した。
そのまま1時間放置し、アミノ基とスクシンイミド基を反応させ、ビオチニル基を導入した。図９は、酸化シリコン表面へのビチオン化学修飾の説明図である。光導波路である酸化シリコン(図中ではＳｉＯ２と表記)の表面には水酸基（−OH)が出ており、3-アミノプロピルトリエトキシシランなどのシランカップリング剤に浸漬することによって、容易に酸化シリコン表面に活性な基であるアミノ基（−NH2)を修飾することができる。さらに、リン酸緩衝液（ｐＨ7.4)にスクシンイミド基を有するビオチン化合物を溶解した溶液中へアミノ基が修飾されたチップを浸漬することにより、容易にたんぱく質（ストレプトアビジン）を特異的に認識するビオチンを修飾することができ、バイオセンサーとしての利用価値が生まれる。Next, the chip was immersed in a weak alkaline aqueous solution for 1 hour and then dried, and immersed in an ethanol solution of 0.2 wt.% 3-aminopropyltriethoxysilane for 2 hours to modify reactive amino groups on the silicon oxide surface. After rinsing with ethanol and drying, 1 / 15M phosphate buffer containing 0.1 mM sulfosuccinimidyl-N- (D-biotinyl) -6-aminohexanate was injected into the liquid cell.
The mixture was allowed to stand for 1 hour, the amino group and the succinimide group were reacted, and a biotinyl group was introduced. FIG. 9 is an explanatory diagram of bition chemical modification to the silicon oxide surface. Hydroxyl groups (-OH) are exposed on the surface of silicon oxide (shown as SiO 2 in the figure), which is an optical waveguide, and it can be easily immersed in a silane coupling agent such as 3-aminopropyltriethoxysilane. An amino group (—NH 2 ) which is an active group can be modified on the silicon oxide surface. Furthermore, the protein (streptavidin) is easily recognized specifically by immersing the chip modified with amino group in a solution in which a biotin compound having a succinimide group is dissolved in phosphate buffer (pH 7.4). Biotin can be modified, creating utility value as a biosensor.
次に、入射角を47.79°に固定し、ビオチニル基に特異的に吸着するストレプトアビジンを１μＭ含有する1/15Mリン酸緩衝液を液セルに注入しながら反射光強度を測定した。図１０に示すように、注入直後から反射光強度が著しく増加し、約20分でほぼ一定になった。
観測された反射率変化量は0.448であった。また、図１１に示すように、入射角を45°から60°まで変化させながら反射光強度を測定したところ、ストレプトアビジンの吸着による膜厚増加により、1次および2次の光導波モードとの結合によるディップが発現する入射角が高角度側にシフトした。このとき、2次の光導波モードの場合、反射光強度が最小になる角度はビオチニル基導入後から0.08°高角度側にシフトした。Next, the incident light angle was fixed at 47.79 °, and the reflected light intensity was measured while injecting a 1 / 15M phosphate buffer containing 1 μM of streptavidin that specifically adsorbs to the biotinyl group into the liquid cell. As shown in FIG. 10, the reflected light intensity increased remarkably immediately after the injection and became almost constant in about 20 minutes.
The observed change in reflectance was 0.448. In addition, as shown in FIG. 11, when the reflected light intensity was measured while changing the incident angle from 45 ° to 60 °, the increase in the film thickness due to the adsorption of streptavidin caused the difference between the primary and secondary optical waveguide modes. The incident angle at which the dip due to the coupling appears shifted to the high angle side. At this time, in the case of the second-order optical waveguide mode, the angle at which the reflected light intensity was minimized shifted to 0.08 ° higher angle after the biotinyl group was introduced.
入射角に対する反射光強度をプロットしたときに得られた反射率曲線をフレネルの式に当てはめてフィッティングを行った結果、ストレプトアビジンが平均膜厚5 nmでビオチニル基に吸着していることが明らかとなった。
金薄膜上にビオチニル基を修飾し、平均膜厚5 nmでストレプトアビジンが吸着すると仮定し、表面プラズモン共鳴が起こる入射角付近での反射率変化量をフレネルの式に基づいて計算したところ、最大で0.15程度であった。
一方、2次の導波モードを利用する場合、計算による反射率変化量の最大値は、0.62であった。また、２次の光導波モードを利用した実験結果は、表面プラズモン共鳴を利用した場合の計算値よりも上回っており、検出の高感度化は明白である。As a result of fitting the reflectance curve obtained by plotting the reflected light intensity against the incident angle to the Fresnel equation, it was found that streptavidin was adsorbed on the biotinyl group with an average film thickness of 5 nm. became.
Assuming that the biotinyl group was modified on the gold thin film and streptavidin was adsorbed at an average film thickness of 5 nm, the amount of reflectance change near the incident angle where surface plasmon resonance occurred was calculated based on the Fresnel equation. It was about 0.15.
On the other hand, when the second-order waveguide mode was used, the maximum value of the reflectance change amount calculated was 0.62. In addition, the experimental result using the second-order optical waveguide mode exceeds the calculated value when the surface plasmon resonance is used, and the enhancement of detection sensitivity is clear.
上述のように、フレネルの式を用いたシミュレーション結果と、実際の実験結果との間には非常に良い相関関係があることから、このシミュレーションによって、様々な反射膜を用いた場合の結果を予測することができる。よって、以下にシミュレーションによって予想される本発明の好適な例を示す。
まずは、反射膜にシリコンを用いた場合である。シリコン反射膜の膜厚は30nm、入射光の波長は633nm、光導波路層は屈折率1.457、厚さ1080nmのシリカガラスとして計算を行った。入射光はｓ偏光とし、2次の導波モードとの結合によるディップを用いた。図１６の左図は、この2次の導波モードとの結合によるディップを示す。ここで、誘電体光導波路表面に屈折率1.45厚さ5nmの物質が吸着した場合の反射率変化量と入射角度の関係を図１６の右図に示す。最大0.26の反射率の変化（減少）が望めることが分かる。As mentioned above, there is a very good correlation between the simulation results using the Fresnel equation and the actual experimental results, so this simulation predicts the results when using various reflective films. can do. Therefore, a preferred example of the present invention predicted by simulation is shown below.
First, it is a case where silicon is used for the reflective film. The calculation was performed assuming that the silicon reflective film had a thickness of 30 nm, the incident light wavelength was 633 nm, the optical waveguide layer had a refractive index of 1.457, and a thickness of 1080 nm. Incident light was s-polarized light, and a dip by coupling with a secondary guided mode was used. The left diagram in FIG. 16 shows a dip due to the coupling with the secondary guided mode. Here, the relationship between the amount of change in reflectance and the incident angle when a substance having a refractive index of 1.45 and a thickness of 5 nm is adsorbed on the surface of the dielectric optical waveguide is shown in the right diagram of FIG. It can be seen that a change (decrease) in reflectance of 0.26 at maximum can be expected.
次に、シリコン反射膜の膜厚27nm、入射光の波長633nm、光導波路層は屈折率1.457、厚さ550nmのシリカガラスを用いた場合の計算結果を示す。ここでは、入射光はｓ偏光とし、１次の導波モードとの結合によるディップを用いた。図１７の左図は、この１次の導波モードとの結合によるディップを示す。ここで、誘電体光導波路表面に屈折率1.45厚さ5nmの物質が吸着した場合の反射率変化量と入射角度の関係を図１７の右図に示す。最大0.25の反射率の変化（減少）が望めることが分かる。
以上から分かるように、反射膜にシリコンを用いた場合でも従来の表面プラズモン共鳴を用いる場合(予想最大反射率変化0.15)より、大きな変化が得られることが分かる。シリコンはガラス材料と非常に密着性が良く、また、熱安定性が非常に高い。よって、安定なセンサーを得ることができる。Next, a calculation result in the case of using silica glass having a silicon reflective film thickness of 27 nm, an incident light wavelength of 633 nm, an optical waveguide layer having a refractive index of 1.457, and a thickness of 550 nm is shown. Here, the incident light is s-polarized light, and a dip by coupling with the first-order waveguide mode is used. The left diagram of FIG. 17 shows a dip due to the coupling with the primary waveguide mode. Here, the right diagram in FIG. 17 shows the relationship between the reflectance change amount and the incident angle when a substance having a refractive index of 1.45 and a thickness of 5 nm is adsorbed on the surface of the dielectric optical waveguide. It can be seen that a change (decrease) in reflectance of up to 0.25 can be expected.
As can be seen from the above, even when silicon is used for the reflective film, a larger change can be obtained than when the conventional surface plasmon resonance is used (predicted maximum reflectance change 0.15). Silicon has very good adhesion to a glass material and has very high thermal stability. Therefore, a stable sensor can be obtained.
次は、反射膜に銅を用いた場合である。銅反射膜の膜厚は39nm、入射光の波長は826.5nm、光導波路層は屈折率1.452、厚さ1400nmのシリカガラスとして計算を行った。入射光はp偏光とし、2次の導波モードとの結合によるディップを用いた。図１８の左図は、この導波モードとの結合によるディップを示す。ここで、誘電体光導波路表面に屈折率1.45厚さ5nmの物質が吸着した場合の反射率変化量と入射角度の関係を図１８の右図に示す。最大0.22の反射率の変化（増加）が望めることが分かる。このように、反射膜に銅を用いた場合でも従来の表面プラズモン共鳴を用いる場合より、大きな変化が得られることが分かる。 Next is a case where copper is used for the reflective film. The calculation was performed assuming that the copper reflective film had a thickness of 39 nm, the incident light wavelength was 826.5 nm, the optical waveguide layer had a refractive index of 1.452, and a thickness of 1400 nm. The incident light was p-polarized light and a dip by coupling with the second-order guided mode was used. The left diagram in FIG. 18 shows a dip due to the coupling with the waveguide mode. Here, the right diagram in FIG. 18 shows the relationship between the reflectance change amount and the incident angle when a substance having a refractive index of 1.45 and a thickness of 5 nm is adsorbed on the surface of the dielectric optical waveguide. It can be seen that a change (increase) in reflectance of 0.22 at the maximum can be expected. Thus, it can be seen that even when copper is used for the reflective film, a greater change can be obtained than when conventional surface plasmon resonance is used.
次に、銅反射膜の膜厚31nm、入射光の波長826.5nm、光導波路層は屈折率1.452、厚さ1400nmのシリカガラスを用いた場合の計算結果を示す。ここでは、入射光はｓ偏光とし、２次の導波モードとの結合によるディップを用いた。図１９の左図は、この導波モードとの結合によるディップを示す。ここで、誘電体光導波路表面に屈折率1.45厚さ5nmの物質が吸着した場合の反射率変化量と入射角度の関係を図１９の右図に示す。最大0.67の反射率の変化（増加）が望めることが分かる。 Next, a calculation result in the case of using silica glass with a copper reflection film thickness of 31 nm, an incident light wavelength of 826.5 nm, an optical waveguide layer with a refractive index of 1.452 and a thickness of 1400 nm is shown. Here, the incident light is s-polarized light, and a dip by coupling with a secondary guided mode is used. The left diagram in FIG. 19 shows a dip due to the coupling with the waveguide mode. Here, the right diagram in FIG. 19 shows the relationship between the reflectance change amount and the incident angle when a substance having a refractive index of 1.45 and a thickness of 5 nm is adsorbed on the surface of the dielectric optical waveguide. It can be seen that a change (increase) in reflectivity of up to 0.67 can be expected.
次に、銅反射膜の膜厚33nm、入射光の波長826.5nm、光導波路層は屈折率1.452、厚さ800nmのシリカガラスを用いた場合の計算結果を示す。ここでは、入射光はｓ偏光とし、1次の導波モードとの結合によるディップを用いた。図２０の左図は、この導波モードとの結合によるディップを示す。ここで、誘電体光導波路表面に屈折率1.45厚さ5nmの物質が吸着した場合の反射率変化量と入射角度の関係を図２０の右図に示す。最大０．６８の反射率の変化（増加）が望めることが分かる。
図１９、図２０から分かるように、反射膜に銅を用い、且つｓ偏光を用いることによって、非常に大きな反射率の変化が得られることが分かる。銅は金や銀に比べるとガラス材料と密着性が良い。よって、安定且つ高感度なセンサーを得ることができる。Next, a calculation result in the case of using a silica glass having a film thickness of 33 nm of the copper reflection film, a wavelength of incident light of 826.5 nm, an optical waveguide layer having a refractive index of 1.452 and a thickness of 800 nm is shown. Here, the incident light is s-polarized light, and a dip by coupling with the first-order waveguide mode is used. The left diagram in FIG. 20 shows a dip due to the coupling with the waveguide mode. Here, the right diagram in FIG. 20 shows the relationship between the reflectance change amount and the incident angle when a substance having a refractive index of 1.45 and a thickness of 5 nm is adsorbed on the surface of the dielectric optical waveguide. It can be seen that a change (increase) in reflectance of 0.68 at maximum can be expected.
As can be seen from FIGS. 19 and 20, it can be seen that a very large change in reflectance can be obtained by using copper for the reflective film and using s-polarized light. Copper has better adhesion to glass materials than gold and silver. Therefore, a stable and highly sensitive sensor can be obtained.
次は、反射膜にクロムを用いた場合である。クロム反射膜の膜厚は10nm、入射光の波長は300nm、光導波路層は屈折率1.488、厚さ300nmのシリカガラスとして計算を行った。入射光はｓ偏光とし、1次の導波モードとの結合によるディップを用いた。図２１の左図は、この導波モードとの結合によるディップを示す。ここで、誘電体光導波路表面に屈折率1.45厚さ5nmの物質が吸着した場合の反射率変化量と入射角度の関係を図２１の右図に示す。最大0.21の反射率の変化（増加）が望めることが分かる。
この場合、センサーとしての感度、及び反射膜の密着性の両方とも良好で、さらには、短波長の光源を用いることによって、誘電体光導波路層を薄くでき、誘電体光導波路層の作製が容易である、と言うメリットもある。The following is a case where chromium is used for the reflective film. The calculation was performed assuming that the chromium reflective film had a thickness of 10 nm, the wavelength of incident light was 300 nm, the optical waveguide layer had a refractive index of 1.488, and a thickness of 300 nm. The incident light was s-polarized light, and a dip by coupling with the first-order waveguide mode was used. The left diagram of FIG. 21 shows a dip due to the coupling with the waveguide mode. Here, the right diagram in FIG. 21 shows the relationship between the reflectance change amount and the incident angle when a substance having a refractive index of 1.45 and a thickness of 5 nm is adsorbed on the surface of the dielectric optical waveguide. It can be seen that a change (increase) in reflectance of 0.21 at the maximum can be expected.
In this case, both the sensitivity as a sensor and the adhesion of the reflective film are good, and furthermore, by using a short wavelength light source, the dielectric optical waveguide layer can be made thin, and the dielectric optical waveguide layer can be easily manufactured. There is also a merit that it is.
次は、反射膜にタンタルを用いた場合である。タンタル反射膜の膜厚は22nm、入射光の波長は1000nm、光導波路層は屈折率1.45、厚さ1000nmのシリカガラスとして計算を行った。入射光はｓ偏光とし、1次の導波モードとの結合によるディップを用いた。図２２の左図は、この導波モードとの結合によるディップを示す。ここで、誘電体光導波路表面に屈折率1.45厚さ5nmの物質が吸着した場合の反射率変化量と入射角度の関係を図２２の右図に示す。最大0.21の反射率の変化（増加）が望めることが分かる。
この場合も、センサーとしての感度、及び反射膜の密着性の両方とも良好である。さらには、長波長の光源を用いることによって、生体分子を観測する際の分子に対するダメージを軽減できるというメリットもある。The following is a case where tantalum is used for the reflective film. The calculation was performed assuming that the tantalum reflective film had a thickness of 22 nm, the incident light wavelength was 1000 nm, the optical waveguide layer had a refractive index of 1.45, and a thickness of 1000 nm. The incident light was s-polarized light, and a dip by coupling with the first-order waveguide mode was used. The left diagram of FIG. 22 shows a dip due to the coupling with the waveguide mode. Here, the right diagram in FIG. 22 shows the relationship between the reflectance change amount and the incident angle when a substance having a refractive index of 1.45 and a thickness of 5 nm is adsorbed on the surface of the dielectric optical waveguide. It can be seen that a change (increase) in reflectance of 0.21 at the maximum can be expected.
Also in this case, both the sensitivity as a sensor and the adhesion of the reflective film are good. Furthermore, the use of a long-wavelength light source has the advantage that damage to the molecules when observing biomolecules can be reduced.
本発明は、上記の通り、光導波モードを利用することによって、被検出試料の検出高感度化を図ることができるという優れた効果を有し、従来の表面プラズモン共鳴を利用する技術よりも、高い感度でかつ小さいサイズの被検出試料を、ラベルを使用することなく検出できるという著しい効果を有するので、ＤＮＡ、抗原−抗体などのたんぱく質、糖鎖などのバイオセンサーおよび金属イオン、有機分子などの化学物質センサーに適用。医療、創薬、食品、環境等の分野において活用できる。また、誘電体層の表面に薄膜を形成すれば、この薄膜の屈折率や誘電率や厚さなどを測定できることから、薄膜材料に対するセンサー、薄膜材料の特性を測定する測定器としても使用が可能である。
As described above, the present invention has an excellent effect that the detection sensitivity of the sample to be detected can be increased by using the optical waveguide mode, and more than the conventional technique using surface plasmon resonance. Since it has a remarkable effect that a sample to be detected with high sensitivity and small size can be detected without using a label, DNA, protein such as antigen-antibody, biosensor such as sugar chain, metal ion, organic molecule, etc. Applicable to chemical sensors. It can be used in fields such as medicine, drug discovery, food, and environment. In addition, if a thin film is formed on the surface of the dielectric layer, the refractive index, dielectric constant, thickness, etc. of this thin film can be measured, so it can also be used as a sensor for thin film materials and a measuring instrument for measuring the characteristics of thin film materials It is.
Claims (4)
該基板側から入射された光が該光導波路内を伝搬する状態となる角度で光を該基板面に入射させ、該基板面側へ出射される反射光の強度の変化を読み取ることによって、該光導波路表面に吸着又は付着した物質の検出を行う光導波モードセンサー用のチップ。A reflective film made of Si coated glass substrate and thereon, a further chip comprising a dielectric layer constituting the optical waveguide formed on said reflective film,
By the light incident from the substrate side is incident light on the substrate surface at an angle a state propagating through the optical waveguide, reading a change in the intensity of the reflected light emitted to the substrate side, the A chip for an optical waveguide mode sensor that detects a substance adsorbed or adhered to the surface of the optical waveguide .
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012098758A1 (en) | 2011-01-20 | 2012-07-26 | 独立行政法人産業技術総合研究所 | Sensing device |
| WO2013011831A1 (en) | 2011-07-15 | 2013-01-24 | 独立行政法人産業技術総合研究所 | Target substance detection chip, target substance detection plate, target substance detection device and target substance detection method |
| US20220299696A1 (en) * | 2019-12-09 | 2022-09-22 | Claudio Oliveira Egalon | Systems And Methods Of Side Illumination Of Waveguides |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2908186B1 (en) * | 2006-11-03 | 2012-08-03 | Commissariat Energie Atomique | IMPROVED OPTICAL DETECTION STRUCTURE FOR PLASMON RESONANCE SENSOR |
| JP2008286778A (en) * | 2007-04-16 | 2008-11-27 | National Institute Of Advanced Industrial & Technology | Microplate with periodic structure and surface plasmon exciting intensified fluorescent microscope using the same or fluorescent microplate reader |
| JP5424229B2 (en) * | 2007-09-28 | 2014-02-26 | 独立行政法人産業技術総合研究所 | Optical waveguide mode sensor using oxide film and manufacturing method thereof |
| JP5248443B2 (en) * | 2008-08-13 | 2013-07-31 | 株式会社神戸製鋼所 | Ultrasonic microscope |
| US20110312103A1 (en) * | 2009-01-30 | 2011-12-22 | National Institute Of Advanced Industrial Science And Technology | Sample detection sensor and sample detection method |
| JPWO2011155179A1 (en) * | 2010-06-10 | 2013-08-01 | コニカミノルタ株式会社 | Analysis element chip |
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| US10768112B2 (en) | 2016-07-12 | 2020-09-08 | National Institute Of Advanced Industrial Science And Technology | Optical detection device and optical detection method |
| JP6936987B2 (en) * | 2017-04-14 | 2021-09-22 | 国立研究開発法人産業技術総合研究所 | Target substance detection chip, target substance detection device and target substance detection method |
| CN108132232A (en) * | 2017-12-28 | 2018-06-08 | 中国地质大学（武汉） | A kind of surface plasma resonance sensor |
| CN108613949B (en) * | 2018-07-30 | 2023-11-17 | 兰州理工大学 | Angle scanning refractive index sensor based on asymmetric metal cladding dielectric waveguide |
| CN111257288A (en) * | 2020-03-30 | 2020-06-09 | 京东方科技集团股份有限公司 | Concentration detection sensor, detection method thereof, and concentration detection device |
| WO2023189138A1 (en) * | 2022-03-30 | 2023-10-05 | 京セラ株式会社 | Optical devices and biosensor |
| CN116008200A (en) * | 2023-02-02 | 2023-04-25 | 深圳大学 | Optical sensor |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002505425A (en) * | 1998-02-24 | 2002-02-19 | ザ・ユニバーシティ・オブ・マンチェスター・インスティテュート・オブ・サイエンス・アンド・テクノロジー | Waveguide structure |
| JP2004117298A (en) * | 2002-09-27 | 2004-04-15 | Fuji Photo Film Co Ltd | Measuring method and apparatus using total reflection attenuation |
| JP2005098997A (en) * | 2003-09-02 | 2005-04-14 | Fuji Photo Film Co Ltd | Measuring apparatus and sensor unit |
| JP2005128419A (en) * | 2003-10-27 | 2005-05-19 | Nec Corp | Optical waveguide structure and its manufacturing method |
-
2006
- 2006-07-10 JP JP2007534274A patent/JP4581135B2/en active Active
- 2006-07-10 WO PCT/JP2006/313647 patent/WO2007029414A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002505425A (en) * | 1998-02-24 | 2002-02-19 | ザ・ユニバーシティ・オブ・マンチェスター・インスティテュート・オブ・サイエンス・アンド・テクノロジー | Waveguide structure |
| JP2004117298A (en) * | 2002-09-27 | 2004-04-15 | Fuji Photo Film Co Ltd | Measuring method and apparatus using total reflection attenuation |
| JP2005098997A (en) * | 2003-09-02 | 2005-04-14 | Fuji Photo Film Co Ltd | Measuring apparatus and sensor unit |
| JP2005128419A (en) * | 2003-10-27 | 2005-05-19 | Nec Corp | Optical waveguide structure and its manufacturing method |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012098758A1 (en) | 2011-01-20 | 2012-07-26 | 独立行政法人産業技術総合研究所 | Sensing device |
| WO2013011831A1 (en) | 2011-07-15 | 2013-01-24 | 独立行政法人産業技術総合研究所 | Target substance detection chip, target substance detection plate, target substance detection device and target substance detection method |
| US20220299696A1 (en) * | 2019-12-09 | 2022-09-22 | Claudio Oliveira Egalon | Systems And Methods Of Side Illumination Of Waveguides |
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