JP7315163B2 - OPTICAL DEVICE, ANALYZER, AND OPTICAL DEVICE MANUFACTURING METHOD - Google Patents

OPTICAL DEVICE, ANALYZER, AND OPTICAL DEVICE MANUFACTURING METHOD Download PDF

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JP7315163B2
JP7315163B2 JP2019054280A JP2019054280A JP7315163B2 JP 7315163 B2 JP7315163 B2 JP 7315163B2 JP 2019054280 A JP2019054280 A JP 2019054280A JP 2019054280 A JP2019054280 A JP 2019054280A JP 7315163 B2 JP7315163 B2 JP 7315163B2
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敬之 本間
雅広 柳沢
正弘 三田
育夫 代木
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Waseda University
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本発明は、光学デバイス、分析装置、及び光学デバイスの製造方法に関し、当該光学デバイスは、例えば表面増強ラマン散乱光を測定して試料分析を行う分析装置に適用して好適なものである。 The present invention relates to an optical device, an analysis apparatus, and a method of manufacturing an optical device, and the optical device is suitable for application to an analysis apparatus that measures surface-enhanced Raman scattered light and analyzes a sample, for example.

表面増強ラマン散乱（以下、ＳＥＲＳ（Surface Enhanced Raman Scattering）とも称する）は、金属表面に励起された表面プラズモンによる電界によって、金属表面に存在する分子が発するラマン散乱光の強度が数桁増強される現象である。表面プラズモンとは、金属に光を照射したときに励起される金属中の自由電子の粗密波である。このようなＳＥＲＳは、試料表面近傍の分子構造の解析等に応用され、従来のラマン分光法におけるラマン散乱光の測定感度を約２桁以上上昇させることができる。 Surface enhanced Raman scattering (hereinafter also referred to as SERS (Surface Enhanced Raman Scattering)) is a phenomenon in which the intensity of Raman scattered light emitted by molecules present on a metal surface is enhanced by several digits due to an electric field generated by surface plasmons excited on the metal surface. A surface plasmon is a compressional wave of free electrons in a metal that is excited when the metal is irradiated with light. Such SERS is applied to the analysis of the molecular structure near the surface of a sample, etc., and can increase the measurement sensitivity of Raman scattered light in conventional Raman spectroscopy by about two orders of magnitude or more.

このような表面増強ラマン分光法を用いた分析装置としては、特許文献１が知られている。特許文献１には、複数の球状金属粒子がプローブの内部に分散し、プローブの表面に複数の金属粒子が露出した構成を有している。このようなプローブを用いた分析装置は、プローブ先端部を試料に近接させた状態で、当該プローブに励起光を入射し、当該励起光によって表面プラズモンの電界を励起させ、試料から放出されるラマン散乱光を増強し、表面増強ラマン散乱光を測定し得るものである。 Patent document 1 is known as an analysis apparatus using such surface-enhanced Raman spectroscopy. Patent document 1 has a configuration in which a plurality of spherical metal particles are dispersed inside a probe and a plurality of metal particles are exposed on the surface of the probe. An analysis apparatus using such a probe can measure surface-enhanced Raman scattered light by injecting excitation light into the probe while the tip of the probe is in close proximity to the sample, exciting the electric field of surface plasmons with the excitation light, and enhancing the Raman scattered light emitted from the sample.

特開２００８－２８１５３０号公報JP 2008-281530 A

特許文献１に開示された分析装置に比べて、試料が発するラマン散乱光を表面プラズモンによって更に増強して、より高感度に試料の構造解析を行い得る分析装置の出現が要望されている。
本発明は上記要望に鑑み、試料からのラマン散乱光を表面プラズモンにより更に増強でき、分析装置に組み込んだ時に、より高感度で表面増強ラマン散乱光の測定を実現できる、簡単な構造を有する光学デバイス、その光学デバイスを備える分析装置、及びその光学デバイスの製造方法を提供することである。 Compared to the analysis apparatus disclosed in Patent Document 1, there is a demand for an analysis apparatus that can perform structural analysis of a sample with higher sensitivity by further enhancing Raman scattered light emitted by the sample using surface plasmons.
It is an object of the present invention to provide an optical device having a simple structure, which can further enhance Raman scattered light from a sample by surface plasmons and can measure surface-enhanced Raman scattered light with higher sensitivity when incorporated in an analyzer, an analyzer equipped with the optical device, and a method for manufacturing the optical device.

一実施形態に係る光学デバイスは、表面増強ラマン散乱光を測定して試料分析を行う分析装置に使用され、第１面と、前記第１面とは反対側の第２面とを有する基材を備え、前記第２面は、少なくとも一部の領域が粗面であり、前記粗面の少なくとも凸部先端には複数の金属ナノ粒子が固着される。 An optical device according to one embodiment is used in an analysis apparatus that measures surface-enhanced Raman scattered light to analyze a sample, and includes a base material having a first surface and a second surface opposite to the first surface, wherein at least a portion of the second surface is a rough surface, and a plurality of metal nanoparticles are adhered to at least the tips of convex portions of the rough surface.

一実施形態に係る分析装置は、上記光学デバイスと、励起光を発する光源と、撮像手段と、前記励起光を、前記光学デバイスを透過後に前記試料に照射させるか、又は前記試料を透過後に前記光学デバイスに照射させ、前記試料から放出された表面増強ラマン散乱光を、前記撮像手段まで導く導光手段と、を備える。 An analysis apparatus according to one embodiment includes the optical device, a light source that emits excitation light, an imaging means, and a light guiding means that irradiates the excitation light onto the sample after passing through the optical device, or irradiates the optical device after passing through the sample, and guides the surface-enhanced Raman scattered light emitted from the sample to the imaging means.

更に、一実施形態に係る光学デバイスの製造方法は、第１面と、前記第１面とは反対側の第２面とを有する基材を備え、前記第２面は、少なくとも一部の領域が粗面であり、前記粗面には複数の金属ナノ粒子が固着される、表面増強ラマン散乱光を測定して試料分析を行う分析装置に使用される光学デバイスの製造方法であって、前記基材の前記第２面の前記一部の領域を含む領域にサンドブラスト処理を施して、前記粗面を形成する工程と、前記粗面に金属をスパッタリングして、前記粗面に前記金属ナノ粒子を固着させる工程と、を含む。 Furthermore, a method for manufacturing an optical device according to one embodiment includes a substrate having a first surface and a second surface opposite to the first surface, wherein the second surface has a rough surface in at least a part of a region, and a plurality of metal nanoparticles are fixed to the rough surface. and sputtering metal onto the roughened surface to adhere the metal nanoparticles to the roughened surface.

本実施形態に係る光学デバイスを備える分析装置の全体構成を示す概略図である。1 is a schematic diagram showing the overall configuration of an analysis apparatus including an optical device according to this embodiment; FIG. 本実施形態に係る光学デバイスの基材の一部の領域（突出先端を含む領域）が、試料表面に近接している状態を示す概略図である。FIG. 4 is a schematic diagram showing a state in which a partial region (region including a protruding tip) of the substrate of the optical device according to this embodiment is close to the surface of the sample; （ａ）は、半球状の金属ナノ粒子を試料表面に点接触させたときの表面プラズモンの励起状態を示す概略図であり、（ｂ）は、半球状の金属ナノ粒子を試料表面に面接触させたときの表面プラズモンの励起状態を示す概略図である。(a) is a schematic diagram showing the excited state of surface plasmons when hemispherical metal nanoparticles are brought into point contact with a sample surface, and (b) is a schematic diagram showing the excited state of surface plasmons when hemispherical metal nanoparticles are brought into surface contact with the sample surface. 本実施形態に係る分析装置における、光学デバイス及び試料の他の配置を示す概略図である。FIG. 4 is a schematic diagram showing another arrangement of optical devices and samples in the analyzer according to the present embodiment; 本実施形態に係る光学デバイスの他の構成を示す概略図である。4 is a schematic diagram showing another configuration of the optical device according to this embodiment; FIG. 本実施形態に係る分析装置における、光学デバイス及び試料の他の構成を示す概略図である。4 is a schematic diagram showing another configuration of the optical device and the sample in the analyzer according to this embodiment; FIG. 実施例１に係る光学デバイスの基材の第２面の粗面を示す走査型電子顕微鏡写真である。4 is a scanning electron micrograph showing the rough surface of the second surface of the substrate of the optical device according to Example 1. FIG. 実施例１及び比較例１に係る光学デバイスを使用して測定したジアルキルジチオリン酸亜鉛（ＺＤＴＰ）薄膜の表面のラマンスペクトルを示すグラフである。4 is a graph showing Raman spectra of the surface of zinc dialkyldithiophosphate (ZDTP) thin films measured using the optical devices according to Example 1 and Comparative Example 1. FIG. 実施例４に係る光学デバイスの基材の第２面の粗面上に金属ナノ粒子が固着された様子を示す走査型電子顕微鏡写真である。10 is a scanning electron micrograph showing a state in which metal nanoparticles are adhered onto the rough surface of the second surface of the substrate of the optical device according to Example 4. FIG. 実施例２に係る光学デバイスを使用して測定したＦｅ２Ｏ３薄膜の表面のラマンスペクトルを示すグラフである。5 is a graph showing a Raman spectrum of the surface of the Fe 2 O 3 thin film measured using the optical device according to Example 2. FIG. 実施例２～４及び比較例２，３に係る光学デバイスの基材の第２面の算術平均粗さＲａと、強度比との関係を示すグラフである。5 is a graph showing the relationship between the intensity ratio and the arithmetic mean roughness Ra of the second surface of the base material of the optical devices according to Examples 2 to 4 and Comparative Examples 2 and 3. FIG.

本実施形態に係る分析装置について図１を参照して説明する。
図１は、本実施形態に係る光学デバイス７を備える分析装置１の全体構成を示す概略図である。分析装置１は、励起光Ｌ１を照射する光源２を有する。光源２から照射された励起光Ｌ１は、光ファイバ３ａを通してハーフミラー（導光手段）４に入射した後、対物レンズ６及び光学デバイス７を順次通過して試料Ｓにまで到達し得るように構成されている。 An analyzer according to this embodiment will be described with reference to FIG.
FIG. 1 is a schematic diagram showing the overall configuration of an analysis apparatus 1 including an optical device 7 according to this embodiment. The analyzer 1 has a light source 2 that emits excitation light L1. The excitation light L1 emitted from the light source 2 enters the half mirror (light guide means) 4 through the optical fiber 3a, and then passes through the objective lens 6 and the optical device 7 in order to reach the sample S.

本実施形態に係る光学デバイス７は、基材２１を備え、例えば基材２１は光が透過可能な透明部材から形成されている。基材２１は、第１面２１ａと、第１面２１ａとは反対側の第２面２１ｂを有している。第２面２１ｂは、第１面２１ａ側とは反対方向に向けて凸面形状に湾曲している。基材２１は、例えば円盤状であり、第２面２１ｂの中心部を突出先端として凸面形状に湾曲し、試料Ｓに配置したときに突出先端が周縁部よりも試料Ｓに近接される。 The optical device 7 according to this embodiment includes a substrate 21, and the substrate 21 is made of, for example, a transparent member through which light can pass. The substrate 21 has a first surface 21a and a second surface 21b opposite to the first surface 21a. The second surface 21b is curved in a convex shape in the direction opposite to the first surface 21a side. The base material 21 is, for example, disc-shaped, and is curved in a convex shape with the central portion of the second surface 21b as a protruding tip, and when placed on the sample S, the protruding tip is closer to the sample S than the peripheral portion.

ここで、光学デバイス７の基材２１の突出先端を含む領域に着目する。図２は、本実施形態に係る光学デバイス７の基材２１の一部の領域（突出先端を含む領域）が、試料表面に近接している状態を示す概略図である。図２に示すように、基材２１の第２面２１ｂは、少なくとも一部の領域（突出先端を含む領域）が粗面であり、凹凸構造を有している。粗面の少なくとも凸部先端Ｔ１には、金属ナノ粒子２２が固着されている。このため、突出先端を含む領域において、粗面の少なくとも凸部先端Ｔ１に固着された単一又は複数の金属ナノ粒子２２が、分析対象となる試料Ｓの表面（単に、試料表面とも称する）Ｓ１に近接又は接触され得る。 Here, attention is focused on the region including the projecting tip of the substrate 21 of the optical device 7 . FIG. 2 is a schematic diagram showing a state in which a partial region (region including the projecting tip) of the substrate 21 of the optical device 7 according to this embodiment is close to the sample surface. As shown in FIG. 2, the second surface 21b of the base material 21 has a rough surface in at least a part of the region (the region including the projecting tip) and has an uneven structure. Metal nanoparticles 22 are fixed to at least the tips T1 of the projections of the rough surface. Therefore, in the region including the protruding tip, the single or multiple metal nanoparticles 22 fixed to at least the tip of the protrusion T1 of the rough surface are the surface of the sample S to be analyzed (simply referred to as the sample surface) S1.

光学デバイス７は、基材２１の第２面２１ｂの湾曲する曲率が調整されており、試料表面Ｓ１と接触する突出先端付近の領域が、励起光Ｌ１のビーム径（励起光Ｌ１の円形状照射領域の直径）よりも小さく、その結果、表面増強ラマン散乱光Ｌ３による面分解能を向上させ得るようになされている。 In the optical device 7, the curvature of the second surface 21b of the substrate 21 is adjusted, and the region near the protruding tip that contacts the sample surface S1 is smaller than the beam diameter of the excitation light L1 (the diameter of the circular irradiation region of the excitation light L1), and as a result, the surface resolution by the surface-enhanced Raman scattered light L3 can be improved.

光学デバイス７では、励起光Ｌ１は、基材２１を第１面２１ａから第２面２１ｂの突出先端を含む領域の当該凸部先端Ｔ１に向けて透過して、更に当該先端Ｔ１に配置された金属ナノ粒子２２を透過して、試料Ｓに照射及び集光される。この際、当該金属ナノ粒子２２は、試料表面Ｓ１に近接した近接面に表面プラズモンを励起させ得る。また、この際、試料Ｓからは励起光Ｌ１によりラマン散乱光を放出し、光学デバイス７により励起された表面プラズモンＰによる電界により、試料Ｓに存在する分子のラマン散乱光の強度が数桁増強されるＳＥＲＳ（表面増強ラマン散乱）が発生し、表面増強ラマン散乱光Ｌ３を放出する。 In the optical device 7, the excitation light L1 is transmitted through the substrate 21 from the first surface 21a toward the projection tip T1 in the region including the projecting tip of the second surface 21b, and further arranged at the tip T1. At this time, the metal nanoparticles 22 can excite surface plasmons on the proximal plane adjacent to the sample surface S1. At this time, Raman scattered light is emitted from the sample S by the excitation light L1, and the electric field generated by the surface plasmons P excited by the optical device 7 causes SERS (surface enhanced Raman scattering) in which the intensity of the Raman scattered light of the molecules present in the sample S is enhanced by several digits, and surface enhanced Raman scattered light L3 is emitted.

上記分析装置１には、光学フィルタ１３、アパーチャー１４、回折格子１５及び撮像手段１６の結像光学系が設けられており、これら結像光学系と光源２とがハーフミラー４を中心に直交して配置されている。分析装置１は、試料Ｓにて発生した表面増強ラマン散乱光Ｌ３を含んだ反射光Ｌ２を、対物レンズ６を介してハーフミラー４に照射させ、当該ハーフミラー４によって反射光Ｌ２を反射させ光ファイバ３ｂを通して光学フィルタ１３に導き、更にアパーチャー１４及び回折格子１５を順に通過してＣＣＤ（Charge Coupled Device）等の撮像手段１６に到達させる。 The analyzer 1 is provided with an imaging optical system including an optical filter 13, an aperture 14, a diffraction grating 15, and an imaging means 16. These imaging optical systems and the light source 2 are arranged orthogonally with the half mirror 4 at the center. The analyzer 1 irradiates the half mirror 4 with the reflected light L2 containing the surface-enhanced Raman scattered light L3 generated in the sample S through the objective lens 6. The reflected light L2 is reflected by the half mirror 4, guided to the optical filter 13 through the optical fiber 3b, and further passed through the aperture 14 and the diffraction grating 15 in order to reach the imaging means 16 such as a CCD (Charge Coupled Device).

結像光学系では、光学フィルタ１３によりフィルタリングして反射光Ｌ２の中から表面増強ラマン散乱光Ｌ３だけを取り出し、アパーチャー１４を通過した光を回折格子１５にてスペクトルとして分離し、撮像手段１６に到達させ得る。このように分析装置１は、撮像手段１６にて得られた画像からラマンスペクトルを分光測定し、ラマンスペクトルの強度から試料Ｓの分子構造を特定する。 In the imaging optical system, only the surface-enhanced Raman scattered light L3 is extracted from the reflected light L2 by filtering with the optical filter 13, and the light that has passed through the aperture 14 is separated as a spectrum by the diffraction grating 15 and made to reach the imaging means 16. As described above, the analysis device 1 spectroscopically measures the Raman spectrum from the image obtained by the imaging means 16, and identifies the molecular structure of the sample S from the intensity of the Raman spectrum.

上述する構成に加えて、この分析装置１は、試料Ｓが載置される基台１２を備えており、当該基台１２が３軸方向に移動することで試料Ｓに対して照射される励起光Ｌ１の焦点を試料Ｓの深さ方向ｚ及び面方向（深さ方向ｚと直交するｘ軸方向及びｙ軸方向）に位置調整可能になっている。実際上、この基台１２は、面方向のｘ軸方向と、このｘ軸方向と直交する同じく面方向のｙ軸方向とに移動する第１ピエゾステージ１０と、ｘ軸方向及びｙ軸方向に直交する深さ方向ｚに移動する第２ピエゾステージ１１とを有し、これら第１ピエゾステージ１０及び第２ピエゾステージ１１により焦点位置を面方向及び深さ方向ｚにÅ（オングストローム）単位で位置調整可能になっている。 In addition to the configuration described above, the analysis apparatus 1 includes a base 12 on which the sample S is placed, and by moving the base 12 in three axial directions, the focal point of the excitation light L1 that irradiates the sample S can be adjusted in the depth direction z and surface direction of the sample S (x-axis direction and y-axis direction perpendicular to the depth direction z). In practice, this base 12 has a first piezo stage 10 that moves in the x-axis direction in the plane direction and the y-axis direction in the same plane direction that is perpendicular to the x-axis direction, and a second piezo stage 11 that moves in the depth direction z that is perpendicular to the x-axis direction and the y-axis direction.

なお、本実施形態においては、試料Ｓが載置される基台１２を３軸方向に移動させることにより、対物レンズ６により集光した励起光Ｌ１の焦点を試料Ｓの面方向及び深さ方向ｚに移動させるようにした場合について述べたが、分析装置１では、対物レンズ６にピエゾアクチュエータ５を設けており、当該ピエゾアクチュエータ５によっても対物レンズ６を深さ方向ｚに移動し得るように構成されている。これにより、分析装置１では、試料Ｓが載置される基台１２を固定しつつ、ピエゾアクチュエータ５によって対物レンズ６を深さ方向ｚに移動させることができ、対物レンズ６により集光した励起光Ｌ１の焦点を試料Ｓの深さ方向ｚに移動し得る。 In this embodiment, the base 12 on which the sample S is placed is moved in three axial directions, thereby moving the focal point of the excitation light L1 condensed by the objective lens 6 in the surface direction and the depth direction z of the sample S. In the analyzer 1, the objective lens 6 is provided with the piezo actuator 5, and the piezo actuator 5 is also configured to move the objective lens 6 in the depth direction z. As a result, in the analyzer 1, the objective lens 6 can be moved in the depth direction z by the piezoelectric actuator 5 while the base 12 on which the sample S is placed is fixed, and the focus of the excitation light L1 condensed by the objective lens 6 can be moved in the depth direction z of the sample S.

対物レンズ６により絞られた励起光Ｌ１の電界（以下、励起光電界と呼ぶ）は、表面プラズモンにより増強され、例えば焦点が試料Ｓ内にある場合、焦点位置で最大となり、かつ焦点位置を中心に急峻な電界勾配となり得る。そこで、この分析装置１では、励起光Ｌ１の焦点位置を試料Ｓの深さ方向ｚに移動し、例えば試料Ｓ内の所定の界面Ｓ２に焦点位置を合わせることで、焦点位置（界面Ｓ２）にて最大の表面増強ラマン散乱光Ｌ３を得て、界面Ｓ２から得られた表面増強ラマン散乱光Ｌ３からラマンスペクトルを分光測定し、ラマンスペクトルの強度から試料Ｓ中の界面Ｓ２の分子構造を特定することができる。 The electric field of the excitation light L1 narrowed down by the objective lens 6 (hereinafter referred to as the excitation light electric field) is enhanced by surface plasmons, and when the focal point is within the sample S, for example, the electric field becomes maximum at the focal position and becomes a steep electric field gradient around the focal position. Therefore, in this analysis apparatus 1, the focal position of the excitation light L1 is moved in the depth direction z of the sample S, and for example, the focal position is adjusted to a predetermined interface S2 in the sample S, so that the maximum surface-enhanced Raman scattered light L3 is obtained at the focal position (interface S2).

光学デバイス７の基材２１の突出先端を含む領域において、第２面２１ｂの粗面を構成する凹凸構造の凸部先端Ｔ１に固着される金属ナノ粒子２２が試料表面Ｓ１に接触させた例を説明する。図３（ａ）は、半球状の金属ナノ粒子２２を試料表面Ｓ１に点接触させたときの表面プラズモンＰの励起状態を示す概略図である。一方、図３（ｂ）は、半球状の金属ナノ粒子２２を試料表面Ｓ１に面接触させたときの表面プラズモンＰの励起状態を示す概略図である。 An example will be described in which the metal nanoparticles 22 fixed to the tips T1 of the protrusions of the concave-convex structure forming the rough surface of the second surface 21b are brought into contact with the sample surface S1 in the region including the protruding tips of the substrate 21 of the optical device 7. FIG. 3A is a schematic diagram showing the excited state of the surface plasmon P when the hemispherical metal nanoparticles 22 are brought into point contact with the sample surface S1. On the other hand, FIG. 3(b) is a schematic diagram showing an excited state of surface plasmons P when hemispherical metal nanoparticles 22 are brought into surface contact with the sample surface S1.

図３（ａ）に示すように、金属ナノ粒子２２は半球状であり、平坦面が第２面２１ｂの粗面の凸部先端Ｔ１に固着された構成を有している。金属ナノ粒子２２は、曲面の頂点が試料表面Ｓ１と点接触している。この状態で、電界振動方向に振動する励起光Ｌ１を平坦面側から曲面頂点を介して試料Ｓに向けて垂直に入射すると、試料表面Ｓ１と点接触した曲面頂点に表面プラズモンＰが励起される。その結果、試料表面Ｓ１や試料Ｓ内にて励起された表面プラズモンＰの電界（単に、プラズモン電界とも称する）によって、試料Ｓの分子からのラマン散乱光の強度を数桁増強させるＳＥＲＳ（表面増強ラマン散乱）が発生し、表面増強ラマン散乱光Ｌ３が得られる。 As shown in FIG. 3(a), the metal nanoparticles 22 are hemispherical, and have a structure in which the flat surface is fixed to the tip T1 of the rough convex portion of the second surface 21b. The apex of the curved surface of the metal nanoparticles 22 is in point contact with the sample surface S1. In this state, when excitation light L1 oscillating in the direction of electric field oscillation is perpendicularly incident on the sample S from the flat surface side through the curved surface vertex, surface plasmons P are excited at the curved surface vertex that is in point contact with the sample surface S1. As a result, SERS (Surface Enhanced Raman Scattering) that increases the intensity of Raman scattered light from the molecules of the sample S by several digits is generated by the electric field of the surface plasmon P excited on the sample surface S1 or in the sample S (also referred to simply as the plasmon electric field), and the surface enhanced Raman scattered light L3 is obtained.

一方、図３（ｂ）に示すように金属ナノ粒子２２は、その平坦面が第２面２１ｂの粗面の凸部先端Ｔ１に固着され、試料表面Ｓ１に強く押し当てられて試料表面Ｓ１に面接触している。この状態でも、平坦面側から面接触した曲面頂点に向けて電界振動方向に振動する励起光Ｌ１を垂直に照射すると、試料表面Ｓ１と面接触した曲面頂点に表面プラズモンＰが励起される。その結果、当該表面プラズモンＰの電界（プラズモン電界）によって、試料Ｓの分子からのラマン散乱光の強度が数桁増強されるＳＥＲＳ（表面増強ラマン散乱）が発生し、表面増強ラマン散乱光Ｌ３が得られる。
なお、図３（ｂ）に示すように、金属ナノ粒子２２を試料表面Ｓ１に対して面接触させた場合、図３（ａ）に示す金属ナノ粒子２２を試料表面Ｓ１に点接触させた場合に比べて、プラズモン電界の強度は、約３倍になる。 On the other hand, as shown in FIG. 3B, the flat surface of the metal nanoparticles 22 is fixed to the rough convex tip T1 of the second surface 21b, and is strongly pressed against the sample surface S1 and is in surface contact with the sample surface S1. Even in this state, when the excitation light L1 oscillating in the electric field vibration direction is vertically irradiated from the flat surface side toward the curved surface vertex that is in surface contact, surface plasmons P are excited at the curved surface vertex that is in surface contact with the sample surface S1. As a result, the electric field (plasmon electric field) of the surface plasmon P generates SERS (surface enhanced Raman scattering) in which the intensity of Raman scattered light from the molecules of the sample S is enhanced by several digits, and surface enhanced Raman scattered light L3 is obtained.
As shown in FIG. 3B, when the metal nanoparticles 22 are brought into surface contact with the sample surface S1, compared to the case where the metal nanoparticles 22 are brought into point contact with the sample surface S1 shown in FIG.

このように、本実施形態に係る光学デバイス７では、基材２１の一部の領域（突出先端を含む領域）に形成された粗面の少なくとも凸部先端Ｔ１に固着された金属ナノ粒子２２を、試料Ｓに近接又は接触して配置することによって、金属ナノ粒子２２の試料Ｓと近接又は接触した面に表面プラズモンＰを励起でき、試料表面Ｓ１や試料Ｓ内にて励起された表面プラズモンＰによりラマン散乱光の強度を数桁増強させた表面増強ラマン散乱光Ｌ３が得られるため、撮像手段１６において表面増強ラマン散乱光Ｌ３の感度を高めることができる。 As described above, in the optical device 7 according to the present embodiment, by arranging the metal nanoparticles 22 fixed to at least the tips T1 of the roughened surface formed in the partial region (region including the protruded tip) of the substrate 21 in proximity to or in contact with the sample S, the surface plasmons P can be excited on the surface of the metal nanoparticles 22 in proximity to or in contact with the sample S, and the surface plasmons P excited on the sample surface S1 or in the sample S enhance the intensity of the Raman scattered light by several digits. Since the Mann-scattered light L3 is obtained, the sensitivity of the surface-enhanced Raman-scattered light L3 in the imaging means 16 can be increased.

また、金属ナノ粒子２２を設けた本実施形態に係る光学デバイス７では、試料表面Ｓ１と光学デバイス７の表面とを、焦点近傍に設置した場合、光学デバイス７の表面の金属ナノ粒子２２（例えばＡｇ）近傍での励起光電界の電界勾配が、表面プラズモンＰの電界増強効果により０．１［ｎｍ］あたり１０３から１０４へ増加する。表面増強ラマン散乱光Ｌ３の強度（ラマン強度）は電界の４乗に比例することが知られているので、０．１［ｎｍ］程度の距離の差におけるラマン強度の変化を感度よく捉えることが可能となる。なお、本実施形態に係る分析装置１では、試料Ｓを載置した基台１２を移動させること、或いはピエゾアクチュエータ５により対物レンズ６を移動させることで、深さ方向ｚ（焦点方向）でのラマン強度の変化を測定し得る。 In addition, in the optical device 7 according to the present embodiment provided with the metal nanoparticles 22, when the sample surface S1 and the surface of the optical device 7 are placed near the focal point, the electric field gradient of the excitation light electric field near the metal nanoparticles 22 (for example, Ag) on the surface of the optical device 7 increases from 10 3 to 10 4 per 0.1 [nm] due to the electric field enhancement effect of the surface plasmon P. Since it is known that the intensity of the surface-enhanced Raman scattered light L3 (Raman intensity) is proportional to the fourth power of the electric field, it is possible to detect changes in Raman intensity with a difference in distance of about 0.1 [nm] with high sensitivity. In addition, in the analyzer 1 according to the present embodiment, by moving the base 12 on which the sample S is placed, or by moving the objective lens 6 with the piezo actuator 5, changes in Raman intensity in the depth direction z (focus direction) can be measured.

この分析装置１では、例えば励起光波長５３２［ｎｍ］のとき、光学デバイス７の表面にて発生した表面プラズモンＰの電界が、当該表面から離れると急激に減衰することから、深さ方向ｚでの測定点以外からの信号の影響を少なくできるという利点がある。ここで、光学デバイス７の表面から所定距離以上離れた箇所では、撮像手段１６による表面増強ラマン散乱光Ｌ３の感度が低下することから、ラマンスペクトルの増強が得られるのは光学デバイス７の表面から深さ方向ｚへ１００［ｎｍ］程度までとなり得る。 In this analysis apparatus 1, for example, when the excitation light wavelength is 532 [nm], the electric field of the surface plasmon P generated on the surface of the optical device 7 rapidly attenuates when it leaves the surface, so there is an advantage that the influence of signals from other than the measurement point in the depth direction z can be reduced. Here, since the sensitivity of the surface-enhanced Raman scattered light L3 by the imaging means 16 is reduced at a location at a predetermined distance or more from the surface of the optical device 7, the enhancement of the Raman spectrum can be obtained up to about 100 [nm] in the depth direction z from the surface of the optical device 7.

因みに、表面プラズモンＰの電界によって増強された励起光電界は、対物レンズ６により集光した励起光Ｌ１の焦点位置で最大になり、焦点位置を中心に急峻な電界勾配になり焦点の前後の電界強度が急激に減少することから、高い深さ分解能が得られる。
光学デバイス７及び試料Ｓ間の界面に、焦点位置が一致したときには、励起光電界の強度が最大となる（すなわち、表面増強ラマン散乱光Ｌ３の強度が最大となる）。これに対して、焦点位置が試料Ｓの内部に移動すると、表面プラズモンＰの電界による増強効果が弱まってゆき、焦点位置での励起光電界の強度が減少してゆく（すなわち、表面増強ラマン散乱光Ｌ３の強度が減少してゆく）。しかし電界勾配の変化は少ないので、高い深さ分解能は維持される。 Incidentally, the excitation light electric field enhanced by the electric field of the surface plasmons P is maximized at the focal position of the excitation light L1 condensed by the objective lens 6, and the electric field gradient becomes sharp around the focal position, and the electric field strength before and after the focal point decreases rapidly, so that high depth resolution can be obtained.
When the focal position coincides with the interface between the optical device 7 and the sample S, the intensity of the excitation light electric field is maximized (that is, the intensity of the surface-enhanced Raman scattered light L3 is maximized). On the other hand, when the focal position moves inside the sample S, the enhancement effect of the electric field of the surface plasmons P weakens, and the intensity of the excitation light electric field at the focal position decreases (that is, the intensity of the surface-enhanced Raman scattered light L3 decreases). However, since the electric field gradient changes less, the high depth resolution is maintained.

分析装置１は、このように焦点位置を深さ方向ｚへ移動させてゆき、焦点近傍に生じる励起光電界の高勾配の強度変化を基に得られた表面増強ラマン散乱光Ｌ３のラマンスペクトルを測定することで、深さ方向ｚに沿って得られたラマンスペクトルの強度変化を基に試料Ｓの深さ方向ｚにおける分子構造の変化を特定し得る。 By moving the focus position in the depth direction z in this way and measuring the Raman spectrum of the surface-enhanced Raman scattered light L3 obtained based on the high-gradient intensity change of the excitation light electric field generated near the focus, the analysis device 1 can specify the change in the molecular structure of the sample S in the depth direction z based on the intensity change of the Raman spectrum obtained along the depth direction z.

次に、本実施形態に係る光学デバイス７の構成を詳細に説明する。
光学デバイス７を構成する基材２１は、上述するように光を透過可能な透明部材からなり、例えば石英、ガラス、サファイア、ダイヤモンド、ＣａＦ２又は加工性に優れたＳｉＯ２から形成される。基材２１は、光学特性や、硬度による粗面加工の容易性から、好ましくは石英又はサファイアから形成される。基材２１は、測定する試料に応じた寸法に形成され、例えば、厚さが０．１[ｍｍ]～１０[ｍｍ]、直径が５［ｍｍ］～１００［ｍｍ］に形成され、一例では、厚さが１[ｍｍ]、直径が２０［ｍｍ］に形成される。 Next, the configuration of the optical device 7 according to this embodiment will be described in detail.
The base material 21 constituting the optical device 7 is made of a transparent member capable of transmitting light as described above, and is made of, for example, quartz, glass, sapphire, diamond, CaF2, or SiO2 excellent in workability. The substrate 21 is preferably made of quartz or sapphire in terms of optical properties and ease of roughening due to hardness. The base material 21 is formed to have dimensions corresponding to the sample to be measured, for example, a thickness of 0.1 [mm] to 10 [mm] and a diameter of 5 [mm] to 100 [mm], and for example, a thickness of 1 [mm] and a diameter of 20 [mm].

基材２１の第２面２１ｂには、上述するように、少なくとも一部の領域（突出先端を含む領域）が粗面である。当該粗面は、ＩＳＯ ２５１７８に準拠して測定される算術平均粗さＲａが、０．１［μｍ］を超えるものであり、好ましくは０．２５［μｍ］以上、１．０［μｍ］以下であり、より好ましくは０．４［μｍ］以上、０．７［μｍ］以下である。算術平均粗さＲａは、レーザー顕微鏡又は原子間力顕微鏡（ＡＦＭ）によって測定することができる。 On the second surface 21b of the base material 21, as described above, at least a part of the region (the region including the projecting tip) is a rough surface. The rough surface has an arithmetic mean roughness Ra measured in accordance with ISO 25178 exceeding 0.1 [μm], preferably 0.25 [μm] or more and 1.0 [μm] or less, more preferably 0.4 [μm] or more and 0.7 [μm] or less. Arithmetic mean roughness Ra can be measured by a laser microscope or an atomic force microscope (AFM).

金属ナノ粒子２２は、Ａｇ、Ａｕ、Ｃｕ、Ｐｄ、Ｐｔ、Ａｌのいずれか、又は誘電率の実部が負の金属のいずれかを含み、好ましくはＡｇを含む。金属ナノ粒子２２は、直径が５［ｎｍ］～１００［ｎｍ]であり、金属ナノ粒子の間の距離を１［ｎｍ］～１００［ｎｍ］であることで、表面プラズモンの電界を増強させることができる。特に、金属ナノ粒子の直径を１０［ｎｍ］～６０［ｎｍ]とすることで更に表面プラズモンの電界を１０００倍以上に増強させることができ、これに相当するラマン散乱光の強度を顕著に増幅することができる。なお、金属ナノ粒子２２は、試料Ｓに対して確実に近接し得るように、一部の領域（第２面２１ｂの凸部先端を含む領域）の粗面に対して、金属ナノ粒子２２をアイランド状に固着させることが望ましい。 The metal nanoparticles 22 include Ag, Au, Cu, Pd, Pt, Al, or a metal with a negative real part of the dielectric constant, preferably Ag. The metal nanoparticles 22 have a diameter of 5 [nm] to 100 [nm], and the distance between the metal nanoparticles is 1 [nm] to 100 [nm], so that the electric field of surface plasmons can be enhanced. In particular, by setting the diameter of the metal nanoparticles to 10 [nm] to 60 [nm], the electric field of the surface plasmon can be further enhanced by 1000 times or more, and the intensity of the corresponding Raman scattered light can be significantly amplified. In order to ensure that the metal nanoparticles 22 can come close to the sample S, it is desirable that the metal nanoparticles 22 be fixed in an island-like manner to the rough surface of a part of the region (the region including the tips of the convex portions of the second surface 21b).

金属ナノ粒子２２の形状は、図３（ａ）に示す半球状に限定されず、円錐状、球体状、角錐状、半楕円状、直方体状、不定形状等の種々の形状であってもよく、これら金属ナノ粒子２２を基材２１の第２面２１ｂ内に埋設させていてもよい。 The shape of the metal nanoparticles 22 is not limited to the hemispherical shape shown in FIG.

次に、本実施形態に係る光学デバイス７の製造方法を詳細に説明する。
まず、第１面２１ａと、第１面２１ａとは反対側の面であって、第１面２１ａ側とは反対方向に向かう凸面形状に湾曲している第２面２１ｂとを有する、例えば光が透過可能な基材２１を用意する。 Next, a method for manufacturing the optical device 7 according to this embodiment will be described in detail.
First, the substrate 21, which has a first surface 21a and a second surface 21b opposite to the first surface 21a and curved in a convex shape facing in the opposite direction to the first surface 21a, is prepared, for example, a light-transmissive substrate 21.

次に、当該基材２１の第２面２１ｂの少なくとも一部の領域（突出先端を含む領域）に、サンドブラスト処理又は機械研磨等の粗面化処理を施して、粗面を形成する。当該粗面化処理は、例えば基材２１の第２面２１ｂの全面に施され、基材２１の第２面２１ｂの全面に粗面が形成される。当該粗面化処理は、第２面２１ｂが曲面であっても容易に粗面を形成できることから、サンドブラスト処理であることが好ましい。 Next, at least a part of the second surface 21b of the base material 21 (the area including the protruding tip) is subjected to surface roughening treatment such as sandblasting or mechanical polishing to form a rough surface. The surface roughening treatment is performed, for example, on the entire second surface 21b of the base material 21 to form a rough surface on the entire second surface 21b of the base material 21 . The surface-roughening treatment is preferably sandblasting because a roughened surface can be easily formed even if the second surface 21b is curved.

サンドブラスト処理で使用する研磨剤としては、特に限定されないが、例えば、アルミナ、ガラス及び炭化ケイ素等のセラミックス材料、スチール、亜鉛、ステンレス、鉄及び銅等の金属材料、並びに合成樹脂の微粒子を、基材２１の硬度に応じて使用され得る。基材２１として石英又はサファイアを使用する場合、基材２１よりも硬度の高い炭化ケイ素の微粒子を含む研磨剤を使用してサンドブラスト処理を行うことが好ましい。なお、当該粗面の算術平均粗さＲａは、例えば、サンドブラスト処理を施す時間や、研磨剤の種類又は粒径を調節することで調整され得る。 The abrasive used in sandblasting is not particularly limited, but for example, ceramic materials such as alumina, glass and silicon carbide, metal materials such as steel, zinc, stainless steel, iron and copper, and fine particles of synthetic resin can be used depending on the hardness of the base material 21. When quartz or sapphire is used as the base material 21 , it is preferable to perform sandblasting using an abrasive containing silicon carbide fine particles having a higher hardness than the base material 21 . The arithmetic mean roughness Ra of the rough surface can be adjusted, for example, by adjusting the sandblasting time and the type or particle size of the abrasive.

次に、当該粗面に金属をスパッタリングして、当該粗面の少なくとも凸部先端に金属ナノ粒子を固着させる。金属のスパッタリングは、例えば基材２１の第２面２１ｂの全面に施される。金属のスパッタリングによれば、第２面２１ｂが曲面であっても容易に金属ナノ粒子をアイランド状に形成できる。金属ナノ粒子２２の直径や、粒子間の距離は、例えば、金属をスパッタリングする時間や回数を調整することで調節され得る。 Next, the rough surface is sputtered with metal to adhere metal nanoparticles to at least the tips of the projections of the rough surface. Sputtering of the metal is applied to the entire second surface 21b of the substrate 21, for example. Metal sputtering can easily form metal nanoparticles in an island shape even if the second surface 21b is a curved surface. The diameter of the metal nanoparticles 22 and the distance between the particles can be adjusted, for example, by adjusting the metal sputtering time and number of times.

以上説明した実施形態に係る光学デバイス７では、一部の領域（凸面形状である基材２１の第２面２１ｂの少なくとも突出先端を含む領域）が粗面であり、当該粗面の少なくとも凸部先端に金属ナノ粒子２２が固着されている。そのため、凸部先端に固着された金属ナノ粒子２２に励起光Ｌ１を集光及び照射でき、金属ナノ粒子２２の試料Ｓと近接又は接触した面に表面プラズモンＰを励起させることができる。このような光学デバイス７を備える分析装置は、表面プラズモンＰをより確実に励起できるため、更にラマン散乱光を増強でき、表面増強ラマン散乱光Ｌ３を従来よりも高感度に測定することができる。表面増強ラマン散乱光Ｌ３を従来よりも高感度に測定できると、種々の試料分析が行えるようになり従来よりも汎用性が向上し得る。また、光学デバイス７は、基材２１及び金属ナノ粒子２２からなる簡単な構造を有するため、安価に再現性良く製造することができる。 In the optical device 7 according to the embodiment described above, a part of the region (the region including at least the protruding tip of the second surface 21b of the base material 21 having a convex shape) is a rough surface, and the metal nanoparticles 22 are fixed to at least the convex tip of the rough surface. Therefore, the metal nanoparticles 22 fixed to the tips of the projections can be focused and irradiated with the excitation light L1, and surface plasmons P can be excited on the surfaces of the metal nanoparticles 22 that are close to or in contact with the sample S. An analyzer equipped with such an optical device 7 can more reliably excite the surface plasmons P, further enhance the Raman scattered light, and measure the surface-enhanced Raman scattered light L3 with higher sensitivity than before. If the surface-enhanced Raman scattered light L3 can be measured with higher sensitivity than before, various sample analyzes can be performed, and versatility can be improved. Moreover, since the optical device 7 has a simple structure composed of the substrate 21 and the metal nanoparticles 22, it can be manufactured at low cost with good reproducibility.

また、光学デバイス７では、第２面２１ｂの少なくとも一部の領域（突出先端を含む領域）が粗面であるため、金属ナノ粒子２２を空間的に高密度に配置することができ、隣接する金属ナノ粒子２２同士の間隙で発生するプラズモン共鳴によって、金属ナノ粒子２２の試料Ｓに近接した近接面に励起される表面プラズモンＰをより確実に増強し得る。 In addition, in the optical device 7, since at least a partial region (region including the projecting tip) of the second surface 21b is a rough surface, the metal nanoparticles 22 can be spatially arranged at a high density, and the plasmon resonance generated in the gaps between the adjacent metal nanoparticles 22 can more reliably enhance the surface plasmons P excited on the adjacent surfaces of the metal nanoparticles 22 close to the sample S.

更に、光学デバイス７では、金属ナノ粒子２２に平坦面を形成したことにより、単なる球状の金属ナノ粒子２２と比較して、金属ナノ粒子２２の試料Ｓに近接した近接面に表面プラズモンＰを励起させることができ、試料Ｓからのラマン散乱光を表面プラズモンＰにより確実に増強し得る。 Furthermore, in the optical device 7, by forming the flat surface on the metal nanoparticles 22, the surface plasmons P can be excited on the surface of the metal nanoparticles 22 close to the sample S, and the Raman scattered light from the sample S can be reliably enhanced by the surface plasmons P, compared to the mere spherical metal nanoparticles 22.

更に、光学デバイス７では、基材２１の第２面２１ｂが突出先端を有しているため、突出先端を試料表面Ｓ１に対して位置決めすることで、突出先端付近の金属ナノ粒子２２を、確実、かつ容易に試料表面Ｓ１に近接し得る。 Furthermore, in the optical device 7, the second surface 21b of the base material 21 has a protruding tip, so by positioning the protruding tip with respect to the sample surface S1, the metal nanoparticles 22 near the protruding tip can be reliably and easily approached to the sample surface S1.

なお、単なる球状でなる金属ナノ粒子の場合は、プラズモン共鳴を起こすために隣に別の金属ナノ粒子が存在する必要があるが、平坦面を有した金属ナノ粒子２２では、隣接する金属ナノ粒子２２が不要なため、孤立した金属ナノ粒子２２であっても試料Ｓからの表面増強ラマン散乱光Ｌ３が得られる。従って、金属ナノ粒子２２の直径に相当する高い空間分解能を実現することができる。 In the case of a metal nanoparticle having a simple spherical shape, another metal nanoparticle needs to be present next to it in order to cause plasmon resonance, but the metal nanoparticle 22 having a flat surface does not need the adjacent metal nanoparticle 22. Therefore, the surface-enhanced Raman scattered light L3 from the sample S can be obtained even with the isolated metal nanoparticle 22. Therefore, high spatial resolution corresponding to the diameter of the metal nanoparticles 22 can be achieved.

以上説明した実施形態に係る光学デバイスの製造方法では、基材２１の第２面２１ｂに、サンドブラスト処理を施して粗面を形成する工程と、粗面に金属をスパッタリングして金属ナノ粒子を固着させる工程とを含む。そのため、複雑な微細加工技術によらず、安価に再現性良く、高感度で表面増強ラマン散乱光の測定を実現できる光学デバイス７を製造することができる。 The method for manufacturing an optical device according to the embodiment described above includes a step of sandblasting the second surface 21b of the substrate 21 to form a rough surface, and a step of sputtering metal onto the rough surface to fix the metal nanoparticles. Therefore, it is possible to manufacture the optical device 7 capable of measuring the surface-enhanced Raman scattered light with high reproducibility at low cost and with high sensitivity without using complicated microfabrication technology.

また、分析装置１では、光学デバイス７に励起光Ｌ１を照射するとともに、励起光Ｌ１の試料Ｓの深さ方向ｚに焦点位置を調整し得るように構成したことにより、焦点位置を中心に急峻な電界勾配になる励起光電界を試料Ｓの深さ方向ｚに移動させて深さ方向ｚに沿って変化するラマン強度の変化から試料分析を行うことができる。この際、この分析装置１では、励起光電界が焦点位置を中心に急峻な電界勾配になり焦点の前後からのラマン散乱光が減少していることから、高い深さ分解能を得ることができる。 In addition, the analysis apparatus 1 is configured so that the optical device 7 is irradiated with the excitation light L1, and the focal position of the excitation light L1 in the depth direction z of the sample S can be adjusted. Therefore, the excitation light electric field that has a sharp electric field gradient centered on the focal position can be moved in the depth direction z of the sample S, and the sample can be analyzed from the change in the Raman intensity that changes along the depth direction z. At this time, in this analysis apparatus 1, the excitation light electric field becomes a sharp electric field gradient centering on the focal position, and the Raman scattering light from before and after the focal point is reduced, so high depth resolution can be obtained.

なお、本実施形態に係る分析装置１及び光学デバイス７は、上述した構成の他に以下に説明する種々の形態を採用できる。
図１に示す分析装置１では、試料表面Ｓ１の上側（励起光Ｌ１が入射する側）に光学デバイス７を配置する例を示して説明したが、光学デバイス７及び試料Ｓの配置はこれに限定されない。図４に示す分析装置のように、光学デバイス７の上側（励起光Ｌ１が入射する側）に試料表面Ｓ１を配置してもよい。図４では、光学デバイス７の第２面２１ｂが上側を向いて配置され、その突出先端に試料表面Ｓ１が接触するように試料Ｓが配置されている。この場合、試料Ｓは、例えば、ガラス基板等の光が透過可能な基板上の試料表面Ｓ１に測定対象となる薄膜が形成される等、光が透過可能に構成される。また、この場合、基材２１は、上述する光が透過可能な透明部材から形成されてもよく、Ｆｅ、Ｎｉ、Ｚｎ、Ｔｉ等の金属材料、Ｓｉ、Ｇｅ、Ｃ等の半導体材料、若しくはそれらの合金材料、又はＩＴＯ等の導電性材料から形成されてもよい。また、この場合、励起光Ｌ１の焦点位置は、例えば試料表面Ｓ１と光学デバイス７との接触面に合わせて使用される。 In addition to the configurations described above, the analysis apparatus 1 and the optical device 7 according to the present embodiment can adopt various configurations described below.
In the analysis apparatus 1 shown in FIG. 1, an example in which the optical device 7 is arranged above the sample surface S1 (the side on which the excitation light L1 is incident) has been described, but the arrangement of the optical device 7 and the sample S is not limited to this. As in the analyzer shown in FIG. 4, the sample surface S1 may be placed above the optical device 7 (the side on which the excitation light L1 is incident). In FIG. 4, the second surface 21b of the optical device 7 is arranged facing upward, and the sample S is arranged so that the sample surface S1 contacts the projecting tip of the optical device 7. In FIG. In this case, the sample S is configured to allow light to pass through, for example, a thin film to be measured is formed on the sample surface S1 on a substrate such as a glass substrate through which light can pass. Further, in this case, the base material 21 may be formed of the above-described transparent member capable of transmitting light, and may be formed of a metal material such as Fe, Ni, Zn, or Ti, a semiconductor material such as Si, Ge, or C, or an alloy material thereof, or a conductive material such as ITO. Also, in this case, the focal position of the excitation light L1 is used in accordance with the contact surface between the sample surface S1 and the optical device 7, for example.

図４に示す分析装置では、励起光Ｌ１は、導光手段によって、試料Ｓ内を試料表面Ｓ１に向けて透過後、例えば金属ナノ粒子２２及び試料表面Ｓ１の接触面に照射及び集光される。この際、試料Ｓからは励起光Ｌ１によりラマン散乱光を放出され、光学デバイス７により励起された表面プラズモンＰによる電界により、試料Ｓに存在する分子のラマン散乱光の強度が数桁増強されるＳＥＲＳ（表面増強ラマン散乱）が発生し、表面増強ラマン散乱光Ｌ３を放出する。このような構成であっても、上述する実施形態に係る分析装置１と同様の効果を得ることができる。 In the analysis apparatus shown in FIG. 4, the excitation light L1 is transmitted through the sample S toward the sample surface S1 by the light guiding means, and then irradiated and focused on, for example, the contact surface between the metal nanoparticles 22 and the sample surface S1. At this time, Raman scattered light is emitted from the sample S by the excitation light L1, and the electric field generated by the surface plasmons P excited by the optical device 7 causes SERS (surface enhanced Raman scattering) in which the intensity of the Raman scattered light of molecules present in the sample S is enhanced by several digits, and surface enhanced Raman scattered light L3 is emitted. Even with such a configuration, effects similar to those of the analyzer 1 according to the above-described embodiment can be obtained.

また、図１に示す分析装置１では、光学デバイス７の第２面２１ｂが凸面形状を有する例を示して説明したが、光学デバイス７の構造はこれに限定されない。光学デバイスは、図５に示す光学デバイス７´のように基材２１´が平板状を有してもよい。光学デバイス７´は、第２面２１ｂ´が平面であって基材２１´が平板状であること以外は、光学デバイス７と同様の構成を有する。具体的には、光学デバイス７´は、第２面２１ｂ´の一部の領域に上記粗面を有し、当該粗面の凸部先端には上記複数の金属ナノ粒子２２が固着されている。ここで、当該一部の領域とは、試料表面Ｓ１に近接又は接触し、かつ励起光Ｌ１が透過又は照射される領域であり、例えば第２面２１ｂ´の中央領域である。光学デバイス７´は、基材２１に代えて基材２１´を使用すること以外、上述する光学デバイス７の製造方法と同様に製造できる。このような構成であっても、上述する実施形態に係る光学デバイス７と同様の効果を得ることができる。 Also, in the analysis apparatus 1 shown in FIG. 1, an example in which the second surface 21b of the optical device 7 has a convex shape has been described, but the structure of the optical device 7 is not limited to this. The optical device may have a flat substrate 21' like the optical device 7' shown in FIG. The optical device 7' has the same configuration as the optical device 7 except that the second surface 21b' is flat and the substrate 21' is flat. Specifically, the optical device 7' has the rough surface in a partial region of the second surface 21b', and the plurality of metal nanoparticles 22 are fixed to the tips of the convex portions of the rough surface. Here, the partial region is a region that is close to or in contact with the sample surface S1 and through which the excitation light L1 is transmitted or irradiated, such as the central region of the second surface 21b'. The optical device 7' can be manufactured in the same manner as the manufacturing method of the optical device 7 described above, except that the substrate 21' is used instead of the substrate 21. FIG. Even with such a configuration, the same effects as those of the optical device 7 according to the embodiment described above can be obtained.

更に、図１に示す分析装置１では、試料表面Ｓ１が平坦な例を示して説明したが、試料表面Ｓ１の形状はこれに限定されない。試料表面Ｓ１は、粗面（例えば、算術平均粗さＲａが０．１［μｍ］以上の粗面）を有してもよい。また、試料表面Ｓ１は、図６に示すように、光学デバイス７´に向かう凸面形状に湾曲している試料表面Ｓ１´であってもよい。また、試料表面の形状が、平滑面又は粗面、及び平坦面又は湾曲面であることは適宜組み合わされて適用されてよい。なお、図６に示すように、光学デバイス７´が平板状である場合、試料表面Ｓ１の形状を湾曲であるものにすると、試料表面Ｓ１の位置分解能を光学デバイス７と同様に向上することができるため好ましい。また、試料Ｓは、固体状に限定されず液体状であってもよく、例えば、ガラス基板等の光が透過可能な基板上に測定対象となる液体層が形成されてもよい。 Furthermore, in the analysis apparatus 1 shown in FIG. 1, an example in which the sample surface S1 is flat has been described, but the shape of the sample surface S1 is not limited to this. The sample surface S1 may have a rough surface (for example, a rough surface with an arithmetic mean roughness Ra of 0.1 [μm] or more). Alternatively, the sample surface S1 may be a sample surface S1' curved in a convex shape toward the optical device 7', as shown in FIG. In addition, the shape of the sample surface may be appropriately combined with a smooth surface or a rough surface and a flat surface or a curved surface. As shown in FIG. 6, when the optical device 7′ is flat, it is preferable to make the sample surface S1 curved so that the positional resolution of the sample surface S1 can be improved in the same manner as the optical device 7. Moreover, the sample S is not limited to a solid state, and may be a liquid state. For example, a liquid layer to be measured may be formed on a substrate such as a glass substrate through which light can be transmitted.

以上説明した、光学デバイス及び試料の配置、光学デバイスの形状、試料の形状は、上述した例に限定されず、適宜組み合わせて適用されてよい。このような組み合わせからなる構成であっても、上述する実施形態に係る分析装置と同様の効果を得ることができる。 The arrangement of the optical device and the sample, the shape of the optical device, and the shape of the sample described above are not limited to the above examples, and may be applied in combination as appropriate. Even with such a combination configuration, it is possible to obtain the same effect as the analyzer according to the embodiment described above.

次に、本実施形態に係る光学デバイスについて、実施例及び比較例によって、より詳細に説明する。
（実施例１及び比較例１）
実施例１に係る光学デバイスは、以下に示す方法で製造した。
まず、厚さが１［ｍｍ］、直径が２０［ｍｍ］の石英からなる基材を用意した。この基材は、第１面と、第１面とは反対側の面であって、第１面側とは反対方向に向けて凸面形状に湾曲している第２面とを有する。 Next, the optical device according to this embodiment will be described in more detail with examples and comparative examples.
(Example 1 and Comparative Example 1)
An optical device according to Example 1 was manufactured by the method described below.
First, a substrate made of quartz having a thickness of 1 [mm] and a diameter of 20 [mm] was prepared. The substrate has a first surface and a second surface opposite to the first surface and curved in a convex shape in a direction opposite to the first surface.

次に、基材の第２面の全面に、炭化ケイ素からなる研磨剤を使用してサンドブラスト処理を施して、算術平均粗さＲａが０．４６［μｍ］の粗面を形成した。算術平均粗さＲａは、ＩＳＯ２５１７８に準拠して測定した。 Next, the entire second surface of the base material was sandblasted using an abrasive made of silicon carbide to form a rough surface with an arithmetic mean roughness Ra of 0.46 [μm]. Arithmetic mean roughness Ra was measured according to ISO25178.

図７は、実施例１に係る光学デバイスの基材の第２面の粗面を示す走査型電子顕微鏡写真である。図７の結果から、実施例１の光学デバイスの基材の第２面には、凹凸構造から構成される粗面が形成されていることが分かる。 7 is a scanning electron micrograph showing the rough surface of the second surface of the substrate of the optical device according to Example 1. FIG. From the results of FIG. 7, it can be seen that the second surface of the base material of the optical device of Example 1 is formed with a rough surface having a concavo-convex structure.

次に、基材の第２面の粗面にＡｇをスパッタリングしてＡｇナノ粒子を粗面化した第２面の凸部先端および凸部の壁面にアイランド状に固着させた。金属ナノ粒子は、直径が５［ｎｍ］～１００［ｎｍ］であり、金属ナノ粒子の間の距離が１［ｎｍ］～１００［ｎｍ］であった。 Next, Ag was sputtered onto the rough surface of the second surface of the base material, and the Ag nanoparticles were adhered to the tips of the roughened second surface of the projections and the wall surfaces of the projections in the form of islands. The metal nanoparticles had a diameter of 5 [nm] to 100 [nm] and a distance between the metal nanoparticles of 1 [nm] to 100 [nm].

比較例１の光学デバイスは、基材の第２面にサンドブラスト処理を施さない点以外は、実施例１と同様の方法で製造した。比較例１の基材の第２面の算術平均粗さＲａは、実施例１と同様に測定すると、０．００［μｍ］である平滑面であった。 An optical device of Comparative Example 1 was manufactured in the same manner as in Example 1, except that the second surface of the substrate was not sandblasted. The arithmetic average roughness Ra of the second surface of the base material of Comparative Example 1 was measured in the same manner as in Example 1, and was a smooth surface of 0.00 [μm].

次いで、ジアルキルチオリン酸亜鉛（ＺＤＴＰ）薄膜（試料Ｓ）を表面に形成したガラス基板を用意した。図１に示す分析装置において、実施例１及び比較例１に係る光学デバイスの第２面を、ガラス基板のＺＤＴＰ薄膜上に第２面に固着されたＡｇナノ粒子が接触するように配置し、ラマンスペクトルを測定した。Ａｇナノ粒子と試料表面Ｓ１との接触は、各光学デバイスを試料表面Ｓ１に向けて垂直方向に１［ｍＮ］の荷重を加えることによって行った。図８は、実施例１及び比較例１に係る光学デバイスを使用して測定したＺＤＴＰ薄膜の表面のラマンスペクトルを示すグラフである。 Next, a glass substrate having a zinc dialkylthiophosphate (ZDTP) thin film (sample S) formed on its surface was prepared. In the analysis apparatus shown in FIG. 1, the second surface of the optical device according to Example 1 and Comparative Example 1 was placed on the ZDTP thin film of the glass substrate so that the Ag nanoparticles fixed to the second surface were in contact, and the Raman spectrum was measured. Contact between the Ag nanoparticles and the sample surface S1 was performed by directing each optical device toward the sample surface S1 and applying a load of 1 [mN] in the vertical direction. 8 is a graph showing Raman spectra of the surface of ZDTP thin films measured using the optical devices according to Example 1 and Comparative Example 1. FIG.

図８から明らかなように、実施例１の光学デバイスを組み込んだ分析装置は、比較例１の光学デバイスを組み込んだ分析装置と比較して、ＺＤＴＰの潤滑膜のＣＨ２ピークが約１０倍の強度で得られることが確認できた。従って、表面増強ラマン散乱光を利用した分析装置において、実施例１の光学デバイスを組み込むことによって、試料からのラマン散乱光を表面プラズモンにより確実に増強でき、高感度で試料の分子構造の解析が行えることが確認できた。 As is clear from FIG. 8, compared with the analyzer incorporating the optical device of Comparative Example 1, the analyzer incorporating the optical device of Example 1 was able to confirm that the CH2 peak of the lubricating film of ZDTP was about 10 times stronger. Therefore, it was confirmed that by incorporating the optical device of Example 1 into an analyzer using surface-enhanced Raman scattered light, the Raman scattered light from the sample can be reliably enhanced by surface plasmon, and the molecular structure of the sample can be analyzed with high sensitivity.

（実施例２～４及び比較例２，３）
実施例２～４及び比較例２，３に係る光学デバイスは、以下に示す方法で製造した。
まず、厚さが１［ｍｍ］、直径が２０［ｍｍ］のサファイアからなる基材を用意した。この基材は、第１面と、第１面とは反対側の第２面を有し、平板状である。すなわち、実施例２～４及び比較例２，３に係る光学デバイスは、図５に示すような構造を有する。 (Examples 2 to 4 and Comparative Examples 2 and 3)
Optical devices according to Examples 2 to 4 and Comparative Examples 2 and 3 were manufactured by the following method.
First, a substrate made of sapphire and having a thickness of 1 [mm] and a diameter of 20 [mm] was prepared. The substrate has a first surface and a second surface opposite to the first surface, and is flat. That is, the optical devices according to Examples 2 to 4 and Comparative Examples 2 and 3 have structures as shown in FIG.

次に、実施例１と同様の方法で、比較例３、実施例２、３及び４の光学デバイスの基材の第２面の全面にサンドブラスト処理を施して、算術平均粗さＲａがそれぞれ０．１［μｍ］の平滑面、０．３［μｍ］、０．５［μｍ］及び０．６５［μｍ］の粗面になるようにした。ここで、算術平均粗さＲａは、サンドブラスト処理を施す時間を調節することによって、変化させた。 Next, in the same manner as in Example 1, the entire surface of the second surface of the base material of the optical devices of Comparative Example 3, Examples 2, 3 and 4 was sandblasted to obtain a smooth surface with an arithmetic mean roughness Ra of 0.1 [μm] and a rough surface with an arithmetic mean roughness Ra of 0.3 [μm], 0.5 [μm] and 0.65 [μm]. Here, the arithmetic mean roughness Ra was changed by adjusting the sandblasting time.

次いで、実施例１と同様の方法で、実施例２～４及び比較例２，３に係る光学デバイスの基材の第２面の全面にＡｇをスパッタリングして、Ａｇからなる複数の金属ナノ粒子を固着させた。 Next, in the same manner as in Example 1, Ag was sputtered all over the second surface of the base material of the optical device according to Examples 2 to 4 and Comparative Examples 2 and 3 to fix a plurality of metal nanoparticles made of Ag.

比較例２の光学デバイスは、基材の第２面に対して、サンドブラスト処理を施さない点以外は、実施例２～４、及び比較例２と同様の方法で製造した。比較例２の基材の第２面の算術平均粗さＲａは、実施例１と同様に測定すると、０．００［μｍ］の平滑面であった。 The optical device of Comparative Example 2 was manufactured in the same manner as in Examples 2 to 4 and Comparative Example 2, except that the second surface of the substrate was not sandblasted. The arithmetic mean roughness Ra of the second surface of the base material of Comparative Example 2 was measured in the same manner as in Example 1, and was a smooth surface of 0.00 [μm].

ここで、図９は、実施例４に係る光学デバイスの基材の第２面の粗面（算術平均粗さＲａが０．６５［μｍ］であって、突出先端を含む領域）上に金属ナノ粒子が固着された様子を示す走査型電子顕微鏡写真である。この結果から、金属ナノ粒子２２は、金属ナノ粒子の直径を５［ｎｍ］～２０［ｎｍ］とし、金属ナノ粒子の間の距離を１［ｎｍ］～２０［ｎｍ］となるアイランド状に配置されていることが確認された。 Here, FIG. 9 is a scanning electron micrograph showing how metal nanoparticles are adhered onto the rough surface of the second surface of the base material of the optical device according to Example 4 (the area including the protruding tip having an arithmetic mean roughness Ra of 0.65 [μm]). From this result, it was confirmed that the metal nanoparticles 22 are arranged in an island shape with a diameter of 5 [nm] to 20 [nm] and a distance between the metal nanoparticles of 1 [nm] to 20 [nm].

次いで、Ｆｅ２Ｏ３の薄膜（試料Ｓ）を表面に形成したガラス基板を用意した。図１に示す分析装置において、実施例２～４及び比較例２，３に係る光学デバイスの第２面を、ガラス基板のＦｅ２Ｏ３の薄膜上に第２面に固着されたＡｇナノ粒子が接触するように配置し、ラマンスペクトルを測定した。Ａｇナノ粒子と試料表面Ｓ１との接触は、各光学デバイスを試料表面Ｓ１に向けて垂直方向に１［ｍＮ］の荷重を加えることによって行った。図１０は、実施例２に係る光学デバイスを使用して測定したＦｅ２Ｏ３の薄膜の表面のラマンスペクトルを示すグラフである。 Next, a glass substrate having a thin film of Fe 2 O 3 (sample S) formed on its surface was prepared. In the analysis apparatus shown in FIG. 1, the second surface of the optical devices according to Examples 2 to 4 and Comparative Examples 2 and 3 was arranged so that the Ag nanoparticles fixed to the second surface were in contact with the Fe 2 O 3 thin film of the glass substrate, and the Raman spectrum was measured. Contact between the Ag nanoparticles and the sample surface S1 was performed by directing each optical device toward the sample surface S1 and applying a load of 1 [mN] in the vertical direction. 10 is a graph showing the Raman spectrum of the surface of the Fe 2 O 3 thin film measured using the optical device according to Example 2. FIG.

この結果より、実施例２に係る光学デバイスを使用すると、Ｆｅ２Ｏ３のピークと、励起光である５３２［ｎｍ］の波長の光に対応するピークとが得られることが確認できた。このとき、Ｆｅ２Ｏ３及び励起光に対応するピークの強度（Ｉｎｔｅｎｓｉｔｙ）を、Ｉ（Ｆｅ２Ｏ３）及びＩ（５３２［ｎｍ］）として読み取り、下記（１）式にて強度比を算出した。
強度比［－］＝Ｉ（Ｆｅ２Ｏ３）／Ｉ（５３２［ｎｍ］）…（１） From these results, it was confirmed that the use of the optical device according to Example 2 yielded a peak of Fe 2 O 3 and a peak corresponding to the excitation light having a wavelength of 532 [nm]. At this time, the peak intensity (Intensity) corresponding to Fe 2 O 3 and excitation light was read as I (Fe 2 O 3 ) and I (532 [nm]), and the intensity ratio was calculated by the following formula (1).
Intensity ratio [−]=I(Fe 2 O 3 )/I(532 [nm]) (1)

実施例２～４及び比較例２，３に係る光学デバイスそれぞれについて、（１）式にて強度比を算出し、その結果を図１１に示した。図１１は、実施例２～４及び比較例２，３に係る光学デバイスの基材の第２面の算術平均粗さＲａと、強度比との関係を示すグラフである。当該強度比は、各光学デバイスによって増強された表面増強ラマン散乱光の検出感度の高さを示す。 For each of the optical devices according to Examples 2 to 4 and Comparative Examples 2 and 3, the intensity ratio was calculated by Equation (1), and the results are shown in FIG. FIG. 11 is a graph showing the relationship between the arithmetic mean roughness Ra of the second surface of the base material of the optical devices according to Examples 2 to 4 and Comparative Examples 2 and 3 and the intensity ratio. The intensity ratio indicates the level of detection sensitivity for surface-enhanced Raman scattered light enhanced by each optical device.

この結果より、基材の第２面が粗面である実施例２～４に係る光学デバイスを使用すると、検出感度の高さを示す強度比が０．９５以上と高く、試料からのラマン散乱光を表面プラズモンにより更に増強でき、より高感度で表面増強ラマン散乱光の測定を実現できることが確認できた。更に、実施例２～４の結果を比較すると、基材の第２面の算術平均粗さＲａが高いほど、更に高感度で表面増強ラマン散乱光を測定できる光学デバイスが得られると確認できた。
以下に、本願出願の当初の特許請求の範囲に記載された発明を付記する。
［１］表面増強ラマン散乱光を測定して試料分析を行う分析装置に使用され、
第１面と、前記第１面とは反対側の第２面とを有する基材を備え、
前記第２面は、少なくとも一部の領域が粗面であり、前記粗面の少なくとも凸部先端には複数の金属ナノ粒子が固着される光学デバイス。
［２］前記基材は光が透過可能な材料によって形成される、［１］に記載の光学デバイス。
［３］前記第２面は、前記第１面側とは反対方向に向かう凸面形状に湾曲しており、前記少なくとも一部の領域は前記凸面形状の突出先端を含む領域である、［１］又は［２］に記載の光学デバイス。
［４］前記基材は平板状である、［１］又は［２］に記載の光学デバイス。
［５］前記粗面の算術平均粗さＲａは、０．２５［μｍ］以上、１．０［μｍ］以下である、［１］～［４］のいずれか１に記載の光学デバイス。
［６］前記基材は、石英又はサファイアから形成される、［１］～［５］のいずれか１に記載の光学デバイス。
［７］前記金属ナノ粒子は、Ａｇ、Ａｕ、Ｃｕ、Ｐｄ、Ｐｔ、Ａｌ及び誘電率の実部が負の金属のいずれかを含む、［１］～［６］のいずれか１に記載の光学デバイス。
［８］［１］～［７］のいずれか１の光学デバイスと、
励起光を発する光源と、
撮像手段と、
前記励起光を、前記光学デバイスを透過後に前記試料に照射させるか、又は前記試料を透過後に前記光学デバイスに照射させ、前記試料から放出された表面増強ラマン散乱光を、前記撮像手段まで導く導光手段と、
を備える分析装置。
［９］第１面と、前記第１面とは反対側の第２面とを有する基材を備え、前記第２面は、少なくとも一部の領域が粗面であり、前記粗面には複数の金属ナノ粒子が固着される、表面増強ラマン散乱光を測定して試料分析を行う分析装置に使用される光学デバイスの製造方法であって、
前記基材の前記第２面の前記一部の領域を含む領域にサンドブラスト処理を施して、前記粗面を形成する工程と、
前記粗面に金属をスパッタリングして、前記粗面に前記金属ナノ粒子を固着させる工程と、
を含む光学デバイスの製造方法。 From this result, it was confirmed that when the optical devices according to Examples 2 to 4, in which the second surface of the base material is roughened, are used, the intensity ratio indicating the high detection sensitivity is as high as 0.95 or more, and the Raman scattered light from the sample can be further enhanced by the surface plasmon, and the measurement of the surface-enhanced Raman scattered light can be realized with higher sensitivity. Furthermore, by comparing the results of Examples 2 to 4, it was confirmed that the higher the arithmetic mean roughness Ra of the second surface of the substrate, the higher the sensitivity of the optical device capable of measuring surface-enhanced Raman scattered light.
The invention described in the original claims of the present application is appended below.
[1] Used in an analyzer for sample analysis by measuring surface-enhanced Raman scattered light,
a substrate having a first surface and a second surface opposite the first surface;
The optical device, wherein at least a part of the second surface is a rough surface, and a plurality of metal nanoparticles are fixed to at least the tips of the convex portions of the rough surface.
[2] The optical device according to [1], wherein the substrate is made of a light-transmissive material.
[3] The optical device according to [1] or [2], wherein the second surface is convexly curved in a direction opposite to the first surface, and the at least part of the region is a region including a projecting tip of the convex shape.
[4] The optical device according to [1] or [2], wherein the substrate is flat.
[5] The optical device according to any one of [1] to [4], wherein the rough surface has an arithmetic mean roughness Ra of 0.25 [μm] or more and 1.0 [μm] or less.
[6] The optical device according to any one of [1] to [5], wherein the substrate is made of quartz or sapphire.
[7] The optical device according to any one of [1] to [6], wherein the metal nanoparticles include any one of Ag, Au, Cu, Pd, Pt, Al, and a metal having a negative real part of dielectric constant.
[8] the optical device of any one of [1] to [7];
a light source that emits excitation light;
imaging means;
a light guiding means for irradiating the excitation light onto the sample after passing through the optical device, or irradiating the optical device after passing through the sample, and guiding the surface-enhanced Raman scattered light emitted from the sample to the imaging means;
Analyzer with
[9] A substrate having a first surface and a second surface opposite to the first surface, wherein at least a part of the second surface is a rough surface, and a plurality of metal nanoparticles are fixed to the rough surface.
sandblasting a region including the partial region of the second surface of the base material to form the rough surface;
Sputtering a metal onto the rough surface to adhere the metal nanoparticles onto the rough surface;
A method of manufacturing an optical device comprising:

１…分析装置、２…光源、４…ハーフミラー（導光手段）、５…ピエゾアクチュエータ（焦点移動手段）、６…対物レンズ、７…光学デバイス、１２…基台（焦点移動手段）、１６…撮像手段、２１…基材、２１ａ…第１面、２１ｂ…第２面、２２…金属ナノ粒子、Ｓ…試料、Ｐ…表面プラズモン DESCRIPTION OF SYMBOLS 1... Analyzer, 2... Light source, 4... Half mirror (light guide means), 5... Piezo actuator (focus moving means), 6... Objective lens, 7... Optical device, 12... Base (focus moving means), 16... Imaging means, 21... Substrate, 21a... First surface, 21b... Second surface, 22... Metal nanoparticles, S... Sample, P... Surface plasmon

Claims (8)

表面増強ラマン散乱光を測定して試料分析を行う分析装置に使用され、
第１面と、前記第１面とは反対側の第２面とを有する基材を備え、
前記第２面は、少なくとも一部の領域が０．４［μｍ］以上１．０［μｍ］以下の範囲の算術平均粗さＲａをもつ粗面であり、前記粗面の少なくとも凸部先端には複数の金属ナノ粒子が固着され、
前記少なくとも一部の領域は、試料表面に近接又は接触した状態で該試料表面に対して透過又は照射されるべき励起光の円形状照射領域より小さい光学デバイス。 Used in analyzers that measure surface-enhanced Raman scattered light for sample analysis,
a substrate having a first surface and a second surface opposite the first surface;
The second surface is a rough surface in which at least a part of the region has an arithmetic mean roughness Ra in the range of 0.4 [μm] to 1.0 [μm], and a plurality of metal nanoparticles are fixed to at least the tips of the projections of the rough surface,
The optical device, wherein the at least part of the region is smaller than the circular irradiation region of the excitation light to be transmitted or irradiated to the sample surface in the vicinity of or in contact with the sample surface. 前記基材は光が透過可能な材料によって形成される、請求項１に記載の光学デバイス。 2. The optical device according to claim 1, wherein the base material is made of a light-transmissive material. 前記第２面は、前記第１面側とは反対方向に向かう凸面形状に湾曲しており、前記少なくとも一部の領域は前記凸面形状の突出先端を含む領域である、請求項１又は２に記載の光学デバイス。 The optical device according to claim 1 or 2, wherein the second surface is curved in a convex shape facing in a direction opposite to the first surface side, and the at least a partial region is a region including a projecting tip of the convex shape. 前記基材は平板状である、請求項１又は２に記載の光学デバイス。 3. The optical device according to claim 1, wherein the substrate is flat. 前記基材は、石英又はサファイアから形成される、請求項１～４のいずれか１項に記載の光学デバイス。 An optical device according to any preceding claim , wherein the substrate is formed from quartz or sapphire. 前記金属ナノ粒子は、Ａｇ、Ａｕ、Ｃｕ、Ｐｄ、Ｐｔ、Ａｌ及び誘電率の実部が負の金属のいずれかを含む、請求項１～５のいずれか１項に記載の光学デバイス。 The optical device according to any one of claims 1 to 5 , wherein the metal nanoparticles include any one of Ag, Au, Cu, Pd, Pt, Al, and a metal having a negative real part of dielectric constant. 請求項１～６のいずれか１項の光学デバイスと、
試料表面に近接又は接触した状態で該試料表面に対して透過又は照射されるべき励起光の円形状照射領域より小さく構成された前記少なくとも一部の領域に対して前記励起光を発する光源と、
撮像手段と、
前記励起光を、前記少なくとも一部の領域を透過後に前記試料に照射させるか、又は前記試料を透過後に前記少なくとも一部の領域に照射させ、前記試料から放出された表面増強ラマン散乱光を、前記撮像手段まで導く導光手段と、
を備える分析装置。 an optical device according to any one of claims 1 to 6 ;
a light source that emits the excitation light to the at least partial area that is smaller than the circular irradiation area of the excitation light that is to be transmitted or irradiated to the sample surface while being in proximity to or in contact with the sample surface;
imaging means;
light guiding means for irradiating the excitation light onto the sample after passing through the at least part of the region , or irradiating the at least part of the region after passing through the sample, and guiding the surface-enhanced Raman scattered light emitted from the sample to the imaging means;
Analyzer with 第１面と、前記第１面とは反対側の第２面とを有する基材を備え、前記第２面は、試料表面に近接又は接触した状態で該試料表面に対して透過又は照射されるべき励起光の円形状照射領域より小さく構成された少なくとも一部の領域が粗面であり、前記粗面には複数の金属ナノ粒子が固着される、表面増強ラマン散乱光を測定して試料分析を行う分析装置に使用される光学デバイスの製造方法であって、
前記第２面の前記少なくとも一部の領域を含む前記基材の領域にサンドブラスト処理を施して、０．４［μｍ］以上１．０［μｍ］以下の範囲の算術平均粗さＲａをもつ前記粗面を形成する工程と、
前記粗面に金属をスパッタリングして、前記粗面に前記金属ナノ粒子を固着させる工程と、
を含む光学デバイスの製造方法。 A base material having a first surface and a second surface opposite to the first surface, wherein at least a partial area of the second surface configured to be smaller than a circular irradiation area of the excitation light to be transmitted or irradiated to the sample surface in the vicinity of or in contact with the sample surface is a rough surface, and a plurality of metal nanoparticles are fixed to the rough surface.
sandblasting a region of the base material including the at least a partial region of the second surface to form the rough surface having an arithmetic mean roughness Ra in the range of 0.4 [μm] to 1.0 [μm];
Sputtering a metal onto the rough surface to adhere the metal nanoparticles onto the rough surface;
A method of manufacturing an optical device comprising:
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008167756A (en) 2004-03-31 2008-07-24 Canon Inc Gold-binding protein
US20090229972A1 (en) 2008-03-13 2009-09-17 Sankaran R Mohan Method and apparatus for producing a feature having a surface roughness in a substrate
US20110128536A1 (en) 2009-12-02 2011-06-02 Bond Tiziana C Nanoscale array structures suitable for surface enhanced raman scattering and methods related thereto
WO2014097886A1 (en) 2012-12-18 2014-06-26 学校法人早稲田大学 Optical device and analysis apparatus
JP2015105838A (en) 2013-11-28 2015-06-08 学校法人早稲田大学 Optical device and analyzer
JP2018072018A (en) 2016-10-25 2018-05-10 学校法人早稲田大学 Optical device and method for manufacturing the same

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008167756A (en) 2004-03-31 2008-07-24 Canon Inc Gold-binding protein
US20090229972A1 (en) 2008-03-13 2009-09-17 Sankaran R Mohan Method and apparatus for producing a feature having a surface roughness in a substrate
US20110128536A1 (en) 2009-12-02 2011-06-02 Bond Tiziana C Nanoscale array structures suitable for surface enhanced raman scattering and methods related thereto
WO2014097886A1 (en) 2012-12-18 2014-06-26 学校法人早稲田大学 Optical device and analysis apparatus
JP2015105838A (en) 2013-11-28 2015-06-08 学校法人早稲田大学 Optical device and analyzer
JP2018072018A (en) 2016-10-25 2018-05-10 学校法人早稲田大学 Optical device and method for manufacturing the same

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