JP2009250951A - Electric field enhancement optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To extend resonance width so that a plurality of wavelengths can be resonated in an electric field enhancement optical device having a micro-resonator structure. <P>SOLUTION: The electric field enhancement optical device D3 is configured to have a micro-resonator structure including a semi-transmissive and semi-reflective first reflection layer, a translucent layer having permeability, and a reflective second reflection layer, and the micro-resonator structure is configured to include a plurality of resonating areas W-Z differed in optical path length so that a plurality of wavelengths can be resonated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electric field-enhanced optical device using electric field enhancement due to an optical confinement phenomenon of a microresonator structure.

  Conventionally, bioluminescence, chemiluminescence, fluorescence, Raman scattering light, etc. are weak, so to detect with higher sensitivity, the measurement light is confined locally to induce plasmons, and the electric field enhancement effect of this plasmon is used to A technology that enhances weak light such as is often used. An example of such an electric field-enhanced optical device is a surface-enhanced Raman device that is used in Raman spectroscopy to enhance Raman scattered light at the surface. By using the surface-enhanced Raman device, the intensity of the measurement light and the intensity of the Raman scattered light itself are enhanced, so that optical measurement can be performed with high sensitivity.

  On the other hand, as another form of the surface-enhanced Raman device, there is one using localized plasmon resonance. This is because when an object is in contact with a metal body, particularly a metal body with nano-order unevenness (metal fine concavo-convex structure) on the surface, the electric field is enhanced by localized plasmon resonance and contacts the surface of the metal body. It is said that the Raman scattered light intensity of the prepared sample is enhanced, and the higher the regularity of the metal fine concavo-convex structure, the more uniform and effective electric field enhancement can be obtained. As one of methods for producing such a metal fine concavo-convex structure on the surface, there is a method in which metal fine particles having high particle size uniformity are produced and the metal fine particles are fixed to the surface of the metal body.

Furthermore, as shown in Patent Document 1, a larger surface-enhanced Raman effect can be obtained by utilizing localized plasmon resonance obtained by using metal fine particles and optical resonance obtained by using a microresonator structure. There are also reports that it has been realized.
Japanese translation of PCT publication No. 2004-530867

  However, in an electric field-enhanced optical device that uses a microresonator structure, the wavelength of measurement light required varies depending on the measurement conditions such as the measurement sample and measurement method. However, there is a problem that the electric field enhancing optical device itself must be replaced with the change of the wavelength of the measuring light. This is because the wavelength of the measurement light that resonates optically (resonance wavelength) is usually determined by the structure of the microresonator, and it is necessary to select the microresonator structure in accordance with the wavelength of the measurement light.

  The present invention has been made in view of the above problems, and in order to cope with a change in wavelength of measurement light with one electric field enhancing optical device, an electric field enhancement having a microresonator structure capable of optical resonance with respect to a plurality of wavelengths. The purpose is to provide an optical device.

  In order to achieve the above object, the present inventor has reached the present invention by paying attention to providing a plurality of resonance regions in the microresonator structure.

That is, the scattered light detection method according to the present invention includes a translucent layer having transparency, a first reflective layer having transflective properties formed on one side of the translucent layer, and another surface of the translucent layer. An electric field-enhanced optical device having a microresonator structure formed of a second reflective layer having reflectivity formed on
The microresonator structure has a plurality of resonance regions having different optical path lengths between the first reflection layer and the second reflection layer,
Optical resonance occurs between the first reflective layer and the second reflective layer by irradiating the first reflective layer with measurement light from the side opposite to the light transmissive layer with respect to the first reflective layer. It is characterized by damaging.

  Here, “semi-transmissive / semi-reflective” means a property having both transparency and reflectivity, and both the transmittance and the reflectance are arbitrary in the range of more than 0% and less than 100%.

  “Microresonator structure” means a resonator structure that causes optical resonance due to multiple interference due to multiple reflection of measurement light taken inside, and that has a resonator length as small as the wavelength of the measurement light. Shall.

  The “optical path length” means nd expressed using the refractive index n of the light transmitting layer and the resonator length d. The “resonator length” is the length from the interface between the first reflective layer and the light transmissive layer to the interface between the second reflective layer and the light transmissive layer (or the thickness of the light transmissive layer). Shall mean.

  The “resonance region” means a generic name of portions having the same optical path length in the microresonator structure.

  In the electric field enhanced optical device according to the present invention, the resonance region is preferably composed of a plurality of microresonance regions, and the microresonance regions are arranged substantially uniformly in the microresonator structure. Preferably there is.

  Here, the “microresonance region” means a portion of each of the resonance regions divided into a plurality of portions that is as small as the measurement light irradiation region or less.

  Furthermore, the optical path length is preferably different depending on the difference in dielectric constant of the light transmitting layer in each resonance region, or preferably different depending on the difference in resonator length in each resonance region.

  The first reflective layer is preferably composed of a metal layer patterned on the surface of the light-transmitting layer, or formed by adhering a plurality of non-aggregated metal fine particles to the surface of the light-transmitting layer. It is preferable that it consists of a metal layer.

  Moreover, it is preferable that a translucent layer consists of a microporous body which has several micropores opened in the surface at the side of the 1st reflection layer.

  Furthermore, it is preferable to optically resonate with measurement light in the visible region to the near infrared region.

  According to the electric field-enhanced optical device according to the present invention, by providing a plurality of resonance regions in the microresonator structure so that optical resonance is possible for a plurality of wavelengths, the electric field is enhanced along with the change of the wavelength of the measurement light. There is no need to replace the optical device. This makes it possible to reduce the cost and simplify the optical measurement. Furthermore, for light having a wavelength width, light in a wider wavelength region can be used, and the efficiency of optical measurement can be improved.

  Hereinafter, although the best embodiment in the present invention is described using a drawing, the present invention is not limited to this.

"Electric field enhanced optical device"
First, the principle of the electric field-enhanced optical device as the basis of the present invention will be described with reference to the drawings.

  1A is a schematic perspective view of a basic electric field-enhanced optical device, and FIG. 1B is a cross-sectional view in the thickness direction through A-A ′ in FIG. 1A.

  As shown in FIG. 1A, the electric field enhancing optical device D1 includes a first reflective layer 10 that is semi-transparent and semi-reflective and supplied with a sample from the incident side (upper side in the drawing) of the measurement light L1, and is transmissive. The device structure is provided with the light-transmitting layer 20 having the above and the second reflective layer 30 having reflectivity in order. The measurement light L1 is wavelength light or light having a wavelength width, and the wavelength is selected according to the substance to be detected.

  For example, the translucent layer 20 is made of a translucent flat substrate, the first reflective layer 10 is made of a metal wire 11 having a regular lattice pattern formed on one surface of the translucent layer 20, and the second The reflective layer 30 is made of a solid metal film formed on the other surface of the translucent layer 20.

  In this case, the material of the translucent layer 20 is not particularly limited, and examples thereof include translucent ceramics such as glass and alumina, translucent resins such as acrylic resins and carbonate resins, and the like. The thickness d of the translucent layer 20 is preferably 300 nm or less because the absorption peak wavelength in the visible light region due to multiple interference is one and can be easily detected, and multiple reflection occurs effectively and the absorption peak due to multiple interference. The wavelength is preferably 100 nm or more because it can be easily detected in the visible light region.

  As a material of the first reflective layer 10 and the second reflective layer 30, any reflective metal can be used, and examples thereof include Au, Ag, Cu, Al, Pt, Ni, Ti, and alloys thereof. The first reflective layer 10 and the second reflective layer 30 may include two or more of these reflective metals.

  The first reflective layer 10 can be formed by forming a solid metal film by, for example, metal vapor deposition, and then performing a known photolithography process, and the second reflective layer 30 is formed by, for example, metal vapor deposition. it can.

  The first reflective layer 10 has a semi-transmissive and semi-reflective property because the fine metal wires 11 themselves are made of a reflective metal but a plurality of pattern gaps 12 transmit light. The pitch of the thin metal wires 11 is not particularly limited as long as the condition smaller than the wavelength of the measurement light L1 is satisfied, and can be appropriately selected according to the measurement conditions, particularly the wavelength of the measurement light L1. For example, when visible light is used as the measurement light L1, it is preferably 200 nm or less. The line width of the fine metal wire 11 is not particularly limited, but is preferably equal to or less than the mean free path of electrons that vibrate in the metal by light, specifically 50 nm or less, and particularly preferably 30 nm or less. When the line width and pitch of the thin metal wires 11 are designed to be smaller than the wavelength of the measurement light L1, that is, when the first reflective layer 10 has an uneven structure smaller than the wavelength of the measurement light L1, the first reflective layer 10 Becomes a transflective thin film having an electromagnetic mesh shielding function against light.

The electric field enhanced optical device D1 can change the resonance wavelength according to the thickness of the light transmitting layer 20 and the average refractive index in the light transmitting layer 20. The thickness of the translucent layer 20, the average refractive index in the translucent layer 20, and the resonance wavelength substantially satisfy the following formula (1). Therefore, if the average refractive index in the translucent layer 20 is the same, the resonance wavelength can be changed only by changing the thickness of the translucent layer 20.
λ≈2nd / (m + 1) (1)
(In the formula, d is the thickness of the translucent layer 20, λ is the resonance wavelength, n is the average refractive index in the translucent layer 20, and m is an integer.)

  When the light-transmitting layer 20 described later has fine holes, the “average refractive index in the light-transmitting layer 20” in the above formula (1) means the refractive index of the anodized metal body and the inside of the fine holes. The average refractive index averaged by adding together the refractive indexes of the above materials (air if there is no filler in the micropores, and filler / or filler and air if there is a filler in the micropores) Means.

  The refractive index is expressed as a complex refractive index when the material has absorption, but the complex portion is zero in the light-transmitting layer 20, and even when the light-transmitting layer 20 has micropores, the refractive index depends on the filling material in the micropores. Since the influence is small, in the above formula (1), the refractive index is displayed without a complex part.

  The resonance condition also varies depending on the physical characteristics and the surface state of the first reflective layer 10 and the second reflective layer 30. The magnitude of this change depends on the thickness of the light transmissive layer 20 and the average in the light transmissive layer 20. Since it is smaller than the influence of the refractive index, the resonance wavelength can be determined by the above formula with an accuracy of several nm order.

The operation of this electric field enhanced optical device will be described below.
As shown in FIG. 1B, when the measurement light L1 is incident on the electric field enhancing optical device D1, a part is reflected on the surface of the first reflective layer 10 according to the transmittance or reflectance of the first reflective layer 10. (Not shown), a part of the light passes through the first reflective layer 10 and enters the light-transmitting layer 20. The light incident on the light transmissive layer 20 is repeatedly reflected between the first reflective layer 10 and the second reflective layer 30. That is, the electric field enhanced optical device D1 has a microresonator structure in which multiple reflection occurs between the first reflective layer 10 and the second reflective layer 30. Therefore, multiple interference due to multiple reflected light occurs in the light-transmitting layer 20, and optical resonance occurs at a resonance wavelength that satisfies the resonance condition, and absorption characteristics that absorb light at the resonance wavelength are exhibited. Then, emitted light L2 having physical characteristics different from the measurement light L1 according to the absorption characteristics is emitted. Furthermore, the electric field in the microresonator structure is enhanced, and an effective electric field enhancing effect can be obtained also on the surface of the first reflective layer 10 that is a light scattering surface.

  In this electric field-enhanced optical device, it is preferable that D1 has a device structure with optical impedance matching so that the number of multiple reflections (finesse) in the light-transmitting layer 20 is maximized. By adopting such a configuration, the absorption peak becomes sharp and a more effective surface enhancement effect can be obtained.

  Further, in this electric field-enhanced optical device D1, since the first reflective layer 10 is made of a metal having free electrons and has a metal fine concavo-convex structure smaller than the wavelength of the measurement light L1, it is localized in the first reflective layer 10. Plasmon resonance is induced. Thereby, the further electric field enhancement effect can be acquired in the surface of a light-scattering surface.

  Local plasmon resonance is a phenomenon in which a metal free electron resonates with an electric field of light and vibrates to generate an electric field. In particular, in a metal layer having a fine metal concavo-convex structure, it is said that a free electric field in a convex portion oscillates in resonance with an electric field of light, thereby generating a strong electric field around the convex portion and causing localized plasmon resonance effectively. . In the present embodiment, as described above, since the first reflective layer 10 has a metal fine concavo-convex structure that is smaller than the wavelength of the measurement light L1, localized plasmon resonance occurs effectively.

  At the wavelength at which the local plasmon resonance occurs, the scattering and absorption of the measurement light L1 are remarkably increased, and the electric field is enhanced on the light scattering surface as in the optical resonance due to the multiple interference. The wavelength at which this localized plasmon resonance occurs (resonance peak wavelength) and the degree of scattering and absorption of the measurement light L1 are determined by the size of the irregularities on the surface of the electric field enhanced optical device D1, the type of metal, and the refraction of the sample in contact with the surface. Depends on rate etc.

  For example, the electric field enhancing optical device D1 uses the electric field enhancing effect on the light scattering surface of the first reflective layer 10 to irradiate the sample or sample cell brought into contact with the light scattering surface with the measurement light L1 and perform Raman scattering. It can be used for surface-enhanced Raman spectroscopy that analyzes light.

  In surface-enhanced Raman spectroscopy, a more effective surface-enhanced Raman effect can be obtained by making the wavelength of the measurement light coincide with the resonance wavelength (hereinafter referred to as Raman-enhanced wavelength) at which the surface-enhanced Raman effect is obtained. Therefore, in the surface-enhanced Raman spectroscopy in which the wavelength of the measurement light irradiated by the measurement sample needs to be changed, the electric field enhanced optical device is preferably designed according to the wavelength of the measurement light.

  However, the control of the Raman enhancement wavelength usually requires precise control of the size of the metal fine concavo-convex structure in the case of a device using localized plasmon resonance, which requires a complicated process.

  However, the electric field-enhanced optical device D1, as shown in the equation (1), has a resonance wavelength that varies depending on the average refractive index and thickness of the light-transmitting layer 20, and thus can be simply changed by changing these factors. The Raman enhancement wavelength changes due to the design change. Therefore, according to this electric field enhancement optical device D1, the electric field enhancement optical device D1 which has the surface enhancement Raman effect in the desired wavelength according to a use can be obtained easily, without requiring complicated device design.

  In this electric field-enhanced optical device D1, multiple interference occurs effectively and strong absorption occurs for light of a specific wavelength, so that the surface-enhanced Raman effect is higher than that of an electric field-enhanced optical device that uses only localized plasmon resonance. Large (for example, an enhancement effect of 100 times or more) and high-precision analysis can be performed.

  The absorption peak due to multiple interference and the absorption peak due to localized plasmon resonance may appear at different wavelengths or may overlap.

  As the material of the first reflective layer 10 and the second reflective layer 30, a reflective material other than metal may be used, but the first reflective layer 10 has a surface enhancement by localized plasmon resonance as described above. A metal capable of obtaining a Raman effect is preferred.

  In the case described above, resonance due to multiple interference and localized plasmon resonance have occurred, and it has been described that the surface enhanced Raman effect caused by independent phenomena can be obtained. It is also conceivable that the surface-enhanced Raman effect is intensified by a phenomenon specific to the configuration.

  Moreover, in this electric field enhancement optical device D1, although the case where the 1st reflection layer 10 was a regular lattice pattern was demonstrated, the pattern shape of the 1st reflection layer 10 is arbitrary and a random pattern may be sufficient. However, a higher structural regularity is preferable because the in-plane uniformity of the microresonator structure is higher and the characteristics are concentrated.

  In the above description, the translucent flat substrate and the solid metal film have been described in the translucent layer 20 and the second reflective layer 30, respectively, but these are obtained by oxidizing a part of the metal body. May be. That is, in this case, a part of the oxidized metal body becomes the translucent layer 20 and the remaining metal body becomes the second reflective layer 30.

  On the other hand, the first reflective layer 10 may be constituted by a plurality of non-aggregated metal fine particles B that are fixed in a regular array in a matrix instead of the fine metal wires 11 having a regular lattice pattern ( Figure 2).

  In this case, as in the case of the thin metal wire 11 described above, it is preferable that the structural regularity is high because the in-plane uniformity of the microresonator structure is high and the characteristics are concentrated. When the metal fine particles B include aggregated particles, there are a portion formed by aggregation of many metal fine particles B and a portion that is not, and the structural regularity of the first reflective layer 10 tends to be low. Since the metal fine particles B of the embodiment are non-aggregated metal fine particles, the first reflective layer 10 having a high structural regularity can be easily formed as compared with the case of including the aggregated particles.

  The material of the metal fine particles B is not limited, and examples thereof include the same metals as the first reflective layer 10 described above, that is, Au, Ag, Cu, Al, Pt, Ni, Ti, and alloys thereof.

  Further, since the metal fine particles B are non-aggregated metal fine particles, (1) the metal fine particles are not associated with each other and the metal fine particles are separated from each other, or (2) the metal fine particles are integrated after the metal fine particles are bonded. It is a metal fine particle contained in any one of particles that cannot be restored to the original state.

  As the first reflective layer 10 to which a plurality of metal fine particles B are fixed in (1), a metal layer that is spaced apart by a certain distance or more so that the metal fine particles B do not associate with each other can be mentioned. In this metal layer, the arrangement of the metal fine particles B may be random or substantially regular.

  Examples of the metal layer in which the metal fine particles B are randomly arranged include a metal layer having an island pattern obtained by an oblique deposition method or the like.

  Examples of the metal layer in which the metal fine particles B are substantially regularly arranged include a dot shape, a mesh shape, a bow tie shape array, and a pattern in which the needle-like metal fine particles B are substantially regularly arranged. Patterning in these cases can be performed by a method using processing such as lithography or a focused ion beam method (FIB method) and self-organization.

  The first reflective layer 10 to which a plurality of fine metal particles B of (2) are fixed is formed integrally in the process of metal growth by fusion or plating, and can be returned to the state before being integrated again. Examples include a plurality of metal fine particles B that cannot be fixed.

  In addition to the above, the first reflective layer 10 can also be formed by applying a dispersion of the metal fine particles B to the surface of the light transmitting layer 20 by a spin coat method or the like and drying. It is preferable that a binder such as resin or protein is contained in the dispersion solution, and the metal fine particles B are fixed to the surface of the translucent layer 20 through the binder. When a protein is used as the binder, the metal fine particles B can be fixed to the surface of the light-transmitting layer 20 by utilizing a binding reaction between the proteins.

  The first reflective layer 10 made of a plurality of metal fine particles B is made of a reflective metal, and has a plurality of voids between the particles, so that it has light transmissivity and transflective properties. The diameter and pitch of the metal fine particles B are designed to be smaller than the wavelength of the measuring light L1, and the first reflective layer 10 has a metal fine concavo-convex structure smaller than the wavelength of the measuring light L1. Also in the present embodiment, the first reflective layer 10 is a semi-transmissive and semi-reflective thin film having an electromagnetic mesh shield function because the metal fine concavo-convex structure is smaller than the wavelength of light.

  As described above, also in the electric field enhanced optical device D2 having the first reflective layer 10 made of the plurality of metal fine particles B, the same effect as the electric field enhanced optical device D1 can be obtained.

<First Embodiment>
FIG. 3 is a schematic perspective view showing the electric field enhanced optical device having the microresonator structure according to the present embodiment.

  The electric field enhancing optical device D3 according to the present embodiment has a microresonator structure composed of four resonance regions W to Z. The four resonance regions W to Z are all formed so as to have different optical path lengths, and each has a different resonance wavelength, so that the resonance width of the resonance wavelength (half-value width of the resonance wavelength spectrum) is expanded as a whole. To do.

  As a result, when the measurement light L1 has a single wavelength, if the optical system is adjusted so that the irradiation region of the measurement light L1 matches any of the resonance regions W to Z, four types can be obtained with one electric field enhancement optical device D3. Therefore, it is possible to cope with the resonance wavelength. As a result, it is not necessary to replace the electric field enhancing optical device with a change in the wavelength of the measuring light L1, and the optical measurement can be reduced in cost and simplified. Naturally, if the number of resonance regions is increased, more resonance wavelengths can be handled.

  On the other hand, when the measurement light L1 is light having a wavelength width, as shown in FIG. 3, if the optical system is adjusted so as to uniformly include the four resonance regions W to Z, one electric field enhancement optical device Light in a wider wavelength region can be used among the light L1 having a wavelength width at D3, and the efficiency of optical measurement can be improved.

In addition, since one electric field-enhanced optical device D3 can cope with many resonance wavelengths, and various types of samples can be measured, this electric field-enhanced optical device D3 can be mass-produced efficiently. <Second embodiment>
FIG. 4 is a schematic perspective view showing the electric field enhanced optical device having the microresonator structure according to the present embodiment.

  The electric field enhancing optical device D4 according to the present embodiment has four resonance regions W to Z, and these resonance regions are divided into a plurality of micro resonance regions W ′ to Z ′ and arranged uniformly. have. As in the first embodiment, the four resonance regions W to Z are all formed so as to have different optical path lengths, and each has a different resonance wavelength, so that the resonance width of the resonance wavelength as a whole is expanded. .

  The size of each of the minute resonance regions W ′ to Z ′ is not particularly limited, but is preferably smaller than the irradiation region of the measurement light L1.

  Thereby, even if an arbitrary place on the light scattering surface of the electric field enhancing optical device D4 is irradiated with the measurement light L1, all the resonance regions W to Z can be included substantially uniformly in the irradiation region. There is no need to make adjustments. As a result, the optical measurement process can be simplified.

  In the following, an example of a microresonator structure will be described with reference to the drawings.

<Third Embodiment>
FIG. 5 is a schematic perspective view showing the electric field enhanced optical device having the microresonator structure according to the present embodiment. In the present embodiment, the description of the same elements as those of the basic electric field enhancing optical devices D1 and D2 described above will be omitted unless particularly necessary.

  The electric field enhanced optical device D5 according to the present embodiment includes a second reflective layer 30, and a translucent layer 20 formed on the flat second reflective layer 30 and having a stepped structure with thicknesses d1 and d2. The first reflective layer 10 made of a plurality of metal fine particles B formed on the respective step surfaces of the step-like structure of the translucent layer 20. The resonance regions where the thickness of the light transmitting layer 20 is d1 and d2 are defined as a resonance region W and a resonance region X, respectively.

  The thicknesses d1 and d2 of the translucent layer 20 having a stepped structure are not particularly limited, and may be appropriately selected depending on the dielectric constant of the material constituting the translucent layer 20 and measurement conditions, particularly the wavelength of the measurement light. Can do.

  Then, the manufacturing method of the electric field enhancing optical device D5 according to the present embodiment starts from the metal body 40 (FIG. 6A), for example, and deposits a dielectric material on the metal body 40 to form the dielectric film 41 having a thickness d2. (FIG. 6B), a mask M is formed on the dielectric film 41 where the resonance region X is to be formed (FIG. 6C), and the thickness of the portion without the mask M is d1 by dry or wet etching. After forming the body film 41, the mask M is removed (FIG. 6D), and then a plurality of metal fine particles B are fixed on the respective step surfaces of the step-like structure of the dielectric film 41 (FIG. 5).

  Here, in the electric field enhanced optical device D5 manufactured by the above-described method, the plurality of metal fine particles B, the dielectric film 41, and the metal body 40 are respectively the first reflective layer 10, the translucent layer 20, and the second reflective layer. Layer 30 is formed.

  The material of the metal body 40 is not particularly limited, but is preferably Al, Ti, W, Pt, Cr, Ni, Cu or the like.

The material of the dielectric film 41 can be appropriately selected as a translucent dielectric layer according to required reflection and transmission wavelength bands, reflectivity, and the like. In particular, SiO ₂ , MgF ₂ , Na ₃ AlF _{6 , TiO 2, ZrO 2, Ta} 2 O 5, ZnS, ZnSe, ZnTe, Si, Ge, Y 2 O 3, is preferably at least one material selected from the group made of _Al 2 _{O 3.} The structure of the dielectric film 41 may be a structure in which layers are formed using layers formed using the above materials. Further, the method for forming the dielectric film 41 is not particularly limited with respect to the method for forming the translucent dielectric layer. For example, the vacuum evaporation method, the IAD (Ion Assisted Deposition) method, the IP (Ion Plating) method, the CVD ( A conventionally known method such as a chemical vapor deposition method or a sputtering method can be used.

  The material, the size of the diameter, the fixing method, etc. of the metal fine particles B are as described above.

On the other hand, the electric field enhanced optical device D5 according to the present embodiment can also be manufactured using a method using oxidation of the metal body 40. That is, the method of manufacturing the electric field enhanced optical device D5 using the oxidation of the metal body 40 starts from, for example, the metal body (Al) 40 (FIG. 6A), and a part of the metal body (Al) is made into a nonporous anode. By performing an oxidation treatment, an anodized metal body (Al ₂ O ₃ ) 41 having a thickness of d2 is formed (FIG. 6B), and a mask is formed on the portion of the anodized metal body (Al ₂ O ₃ ) 41 to be the resonance region X. M is formed (FIG. 6C), and the anodized metal body (Al ₂ O ₃ ) 41 is formed by dry or wet etching so that the thickness of the portion without the mask M is d1, and then the mask M is removed ( 6D), and then a plurality of fine metal particles B are fixed on the respective step surfaces of the stepped structure of the anodized metal body (Al ₂ O ₃ ) 41 (FIG. 5).

Here, in the electric field enhanced optical device D5 manufactured by the above method, the plurality of metal fine particles B, the anodized metal body (Al ₂ O ₃ ) 41, and the metal body 40 are the first reflective layer 10 and the translucent light, respectively. The layer 20 and the second reflective layer 30 are formed.

  Anodization can be performed by using aluminum as an anode, immersing it in an electrolyte together with a cathode, and applying a voltage between the anode and the cathode. The shape of the metal body (Al) 40 is not limited, and a plate shape or the like is preferable. Further, it may be used in a form with a support such as a layered metal body (Al) 40 on the support. Carbon, aluminum, or the like is used as the cathode.

  Since the film structure of the anodized film varies depending on conditions such as the type of electrolyte, current density, and temperature, the electrolyte is usually treated with a porous type (porous type) or non-porous type (barrier type). It is selected as appropriate depending on the processing. Generally, when a treatment is performed with an electrolytic solution having a high film solubility, a porous film is formed. Examples of the porous electrolyte include sulfuric acid, oxalic acid, phosphoric acid, and chromic acid. The porous film is composed of a dense and non-porous lower layer and a porous upper layer. On the other hand, the non-porous type is produced when treatment is carried out mainly with a neutral solution such as boric acid or ammonium tartrate.

  In addition, although only Al was mentioned as a main component of the metal body 40, arbitrary metals can be used if the metal oxide produced | generated by anodization has translucency. Other than Al, Ti, Ta, Hf, Zr, Si, In, Zn, etc. can be used. The metal body 40 may include two or more types of metals that can be anodized.

  Hereinafter, the operation of the electric field enhancing optical device D5 according to the present embodiment will be described.

  By the method as described above, the electric field enhanced optical device D5 according to the present embodiment is constituted by the resonance region W and the resonance region X having different resonance wavelengths by the light-transmitting layer 20 having a step-like structure with thicknesses d1 and d2, respectively. As a whole, the resonance width of the resonance wavelength is expanded.

  Therefore, as in the first embodiment, optical measurement using single-wavelength measurement light can support a plurality of resonance wavelengths, and as a result, the electric field-enhanced optical device with the wavelength change of the measurement light L1. It is not necessary to replace D5, and optical measurement can be reduced in cost and simplified. Further, in the case where the measurement light L1 is light having a wavelength width, if the optical system is adjusted, light in a wider wavelength region can be used in the light L1 having the wavelength width by one electric field enhancing optical device D5. It is possible to improve the efficiency of optical measurement.

  And the multiple interference by multiple reflected light occurs in the translucent layer 20, it resonates in the specific wavelength which satisfy | fills resonance conditions, and the absorption characteristic which absorbs the light of a resonant wavelength is shown. Then, emitted light L2 having physical characteristics different from the measurement light L1 according to the absorption characteristics is emitted. Furthermore, the electric field in the microresonator structure is enhanced, and an effective electric field enhancing effect can be obtained also on the surface of the first reflective layer 10 that is a light scattering surface.

  Further, in this electric field-enhanced optical device, D5 has a metal fine concavo-convex structure in which the first reflective layer 10 is made of a metal having free electrons and is smaller than the wavelength of the measurement light L1, so In-plasmon resonance is induced. Thereby, the further electric field enhancement effect can be acquired in the surface of a light-scattering surface.

  In the present embodiment, the regions having different resonance wavelengths by the light-transmitting layer 20 having the staircase structure having the thicknesses d1 and d2 have been described as the resonance region W and the resonance region X, respectively. W ′ and the minute resonance region X ′ may be used. In other words, in this case, FIG. 5 is a schematic perspective view showing a part of the electric field enhanced optical device D5 having a plurality of microresonant regions W ′ and microresonant regions X ′. The same effect as the embodiment can be obtained.

<Fourth Embodiment>
FIG. 7 is a schematic perspective view showing the electric field enhanced optical device having the microresonator structure according to the present embodiment. This embodiment is different from the third embodiment in that the step boundary surface of the step-like structure of the electric field enhancing optical device D7 is between the translucent layer 20 and the second reflective layer 30. Therefore, the description of the same elements as those of the third embodiment is omitted unless particularly necessary.

  The electric field enhancing optical device D7 according to the present embodiment is formed in a complementary manner on the second reflective layer 30 having a stepped structure and the stepped structure of the second reflective layer 30, and has a thickness of d1 and d2. The light-transmitting layer 20 having an inverted stepped structure and the first reflective layer 10 made of a plurality of metal fine particles B formed on the light-transmitting layer 20 are included. The resonance regions where the thickness of the light transmitting layer 20 is d1 and d2 are defined as a resonance region W and a resonance region X, respectively.

  And the manufacturing method of the electric field enhancement optical device D7 by this embodiment starts from the metal body 40 (FIG. 8A), for example, forms the mask M on the metal body 40 of the part made into the resonance area W (FIG. 8B), After forming the metal body 40 by dry or wet etching so that the thickness of the portion without the mask M becomes d2-d1 (d2> d1), the mask M is removed (FIG. 8C), and a stepped structure is obtained. A dielectric material is deposited on the metal body 40 to form a dielectric film 41 having a thickness d2 (FIG. 8D), and the dielectric film 41 is formed so as to form a portion of the dielectric film 41 having a thickness d1. The surface is polished at the position of line C in the figure (FIG. 8E), and then a plurality of metal fine particles B are fixed onto the flattened dielectric film 41 (FIG. 7).

  Here, in the electric field-enhanced optical device D7 manufactured by the above method, the plurality of metal fine particles B, the dielectric film 41, and the metal body 40 are respectively the first reflective layer 10, the translucent layer 20, and the second reflective layer. Layer 30 is formed.

  The method for polishing the dielectric 41 is not particularly limited, and a conventionally known method can be used. An example is chemical mechanical polishing. By performing a chemical mechanical polishing (CMP) process, the surface of the dielectric film can be planarized. For the CMP treatment, a CMP slurry such as PANANERLITE-7000 manufactured by Fujimi Incorporated, GPXHSC800 manufactured by Hitachi Chemical Co., Ltd., CL-1000 manufactured by Asahi Glass (Seimi Chemical Co., Ltd.), or the like can be used.

On the other hand, the electric field enhanced optical device D7 according to the present embodiment can also be manufactured using a method using oxidation of the metal body 40. That is, the manufacturing method of the electric field enhanced optical device D7 using the oxidation of the metal body 40 starts from, for example, the metal body (Al) 40 (FIG. 8A), and is formed on the metal body (Al) 40 of the portion to be the resonance region W. A mask M is formed (FIG. 8B), and after forming the metal body 40 by dry or wet etching so that the thickness of the portion without the mask M becomes d2-d1 (d2> d1), the mask M is removed ( 8C), a part of the metal body (Al) 40 having a stepped structure is anodized to form an anodized metal body (Al ₂ O ₃ ) 41 having a thickness d2 (FIG. 8D). metal body _{(Al 2} O 3) thickness of 41 to polish the surface at the position of FIG midline C anodic-oxidized metal _{(Al 2} O 3) 41 so as to form a portion serving as d1 (FIG. 8E) Then, the anodic acid in which the plurality of fine metal particles B are flattened Fixed on the metal member _{(Al 2} O 3) 41 _(FIG. 7) is intended.

Here, in the electric field enhanced optical device D7 manufactured by the above method, the plurality of metal fine particles B, the anodized metal body (Al ₂ O ₃ ) 41, and the metal body 40 are the first reflective layer 10 and the translucent light, respectively. The layer 20 and the second reflective layer 30 are formed.

As a method for polishing the anodized metal body (Al ₂ O ₃ ) 41, an etching removal method or a CMP method is used. In terms of ease of production, an etching method, specifically, a wet etching method is preferable, and hydrofluoric acid, phosphoric acid / hydrochloric acid mixed acid, sodium hydroxide, or the like can be used.

  Hereinafter, the operation of the electric field enhanced optical device D7 according to the present embodiment will be described.

  By the method as described above, the electric field enhanced optical device D7 according to the present embodiment is constituted by the resonance region W and the resonance region X having different resonance wavelengths, respectively, by the translucent layer 20 having the step-like structure having the thicknesses d1 and d2. As a whole, the resonance width of the resonance wavelength is expanded.

  Therefore, also in this embodiment, the same effect as that of the third embodiment can be obtained. Furthermore, in the present embodiment, the sample supply surface (the surface of the first reflective layer 10) has a flat structure, so that the sample can be handled more easily.

<Fifth Embodiment>
FIG. 9 is a perspective view showing a part of the metal body (Al) 40 converted to an anodized metal body (Al ₂ O ₃ ) 41 by subjecting the metal body (Al) 40 to a porous type anodizing treatment. In the figure, fine holes 41 a are formed in the anodized metal body (Al ₂ O ₃ ) 41.

When the metal body 40 is anodized, an oxidation reaction proceeds from the surface in a direction substantially perpendicular to the surface, and an anodized metal body (Al ₂ O ₃ ) 41 is generated. The anodized metal body (Al ₂ O ₃ ) 41 generated by anodization has a structure in which a number of fine columnar bodies having a substantially regular hexagonal shape are arranged without gaps in plan view. A minute hole 41a extending substantially straight from the surface in the depth direction is opened at a substantially central portion of each fine columnar body, and the bottom surface of each fine columnar body has a rounded shape.

  The structure of the anodized film produced by anodization is shown by Hideki Masuda, “Preparation of mesoporous alumina by anodization and application as a functional material”, Material Technology Vol.15, No.10, 1997, p.34, etc. Are described in detail.

As an example of suitable anodizing conditions for producing an anodized metal body (Al ₂ O ₃ ) 41 having an ordered arrangement structure, when oxalic acid is used as the electrolyte, the electrolyte concentration is 0.5 M, and the solution temperature is 14-16. And an applied voltage of 40 to 40 ± 0.5V. The fine holes 21 generated under these conditions have, for example, a diameter of 5 to 200 nm and a pitch of 10 to 400 nm.

  The pitch of the fine holes 41a is not particularly limited as long as the condition smaller than the wavelength of the measurement light L1 is satisfied. For example, when visible light is used as the measurement light L1, it is preferably 200 nm or less.

Hereinafter, in the present embodiment, the anodized metal body (Al ₂ O ₃ ) 41 having the fine holes 41a and the untreated metal body (Al) 40 are referred to as the translucent layer 20 and the second reflective layer 30, respectively. Become.

  FIG. 10F is a schematic cross-sectional view illustrating the electric field enhanced optical device having the microresonator structure according to the present embodiment. This embodiment is different from the fourth embodiment in that the translucent layer 20 has fine holes 41a. Therefore, the description of the same elements as those of the fourth embodiment is omitted unless particularly necessary.

The electric field enhancing optical device D10 according to the present embodiment is formed in a complementary manner on a metal body (Al) 40 having a stepped structure and the stepped structure of the metal body (Al) 40, and has a thickness of d1 and d2. Anodized metal body (Al ₂ O ₃ ) 41 having a reverse staircase structure and having fine holes 41a, a metal material 70 filled in the fine holes 41a, and an anodized metal body (Al ₂ O ₃ ) And a metal layer made of a plurality of metal fine particles B formed on 41. The resonance regions where the thickness of the anodized metal body (Al ₂ O ₃ ) 41 (translucent layer 20) is d1 and d2 are defined as a resonance region W and a resonance region X, respectively.

  The fine holes 41a are filled with a metal material 70, and the metal to be filled is not particularly limited as long as the metal is a metal, and Au, Ag, Cu, Al, Pt, Ni, Ti, and the like are preferable, and Au and Ag are preferable. Particularly preferred.

And the manufacturing method of the electric field enhancement optical device D10 by this embodiment starts from the metal body 40 (FIG. 10A), for example, forms the mask M on the metal body 40 of the part made into the resonance area W (FIG. 10B), After forming the metal body 40 by dry or wet etching so that the thickness of the portion without the mask M becomes d2-d1 (d2> d1), the mask M is removed (FIG. 10C), and a stepped structure is obtained. A part of the metal body (Al) 40 is subjected to a porous type anodizing treatment to form an anodized metal body (Al ₂ O ₃ ) 41 having a fine hole 41a and having a thickness d2 (FIG. 10D). oxidized metal _{(Al 2} O 3) thickness of 41 to polish the surface at the position of FIG midline C anodic-oxidized metal _{(Al 2} O 3) 41 so as to form a portion serving as d1 (FIG. 10E ), Fine by metal material 70 Then filled with 41a in which a plurality of metal fine particles B anodized metal body a flat _{(Al 2} O 3) is fixed on the 41 (FIG. 10F).

A method of filling the fine holes 41a with a metal material can be performed, for example, by electroplating. When performing by electroplating, it is necessary to ensure the conductivity of the bottom of the fine hole 41a. As a method of ensuring conductivity, for example, a method of controlling the conditions so that the anodized metal body (Al ₂ O ₃ ) 41 at the bottom of the fine hole 41a becomes particularly thin when anodizing is performed, or anodizing is performed. A method of thinning the bottom anodized metal body (Al ₂ O ₃ ) 41 by repeating a plurality of times, a method of removing the bottom anodized metal body (Al ₂ O ₃ ) 41 by etching, or the like can be considered. Electroplating is performed by treating a metal body having the fine holes 41a in a plating solution. While the anodized metal body (Al ₂ O ₃ ) 41 is non-conductive, the bottom of the fine hole 41a is ensured to be conductive by the above treatment. For this reason, the plated metal material is preferentially deposited in the fine hole 41a having a strong electric field, and the fine hole 41a is filled with the plated metal material.

  Hereinafter, the operation of the electric field enhancing optical device D10 according to the present embodiment will be described.

  By the method as described above, the electric field enhanced optical device D10 according to the present embodiment is constituted by the resonance region W and the resonance region X having different resonance wavelengths by the light-transmitting layer 20 having a step-like structure with thicknesses d1 and d2, respectively. As a whole, the resonance width of the resonance wavelength is expanded.

  Therefore, also in this embodiment, the same effect as that of the fourth embodiment can be obtained.

  Furthermore, since the metal material 70 is filled in the fine holes 41a, the dielectric constant of the light transmitting layer 20 is different from that of the fourth embodiment. That is, the resonance wavelength can be finely adjusted by controlling the dielectric constant in the light transmitting layer 20. For example, metals such as Au and Ag have a small refractive index from the visible region to the near-infrared region, so that the resonance wavelength of the microresonator structure can be easily adjusted by filling the metal.

  Further, by adsorbing the metal fine particles B on the surface to the metal material 70 filled in the fine holes 41a, the regularity of the arrangement of the metal fine particles B is improved and the adhesion to the anodized metal body (Al2O3) 41 is improved. Can be improved.

<Sixth Embodiment>
FIG. 11F is a schematic cross-sectional view illustrating the electric field enhanced optical device having the microresonator structure according to the present embodiment. This embodiment is different from the fifth embodiment in that a difference in optical path length of each resonance region is provided by a difference in dielectric constant of the light transmitting layer 20 in each region. Therefore, the description of the same elements as those of the fifth embodiment is omitted unless particularly necessary.

The electric field enhanced optical device D11 according to the present embodiment includes a metal body (Al) 40 and an anodized metal body (Al ₂ O ₃ ) having a fine hole 41a and formed on the metal body (Al) 40. 41, a first metal material 70 and a second metal material 80 filled in the fine holes 41a, and a plurality of metal fine particles B formed on the anodized metal body (Al ₂ O ₃ ) 41. It consists of a metal layer. The resonance regions in which the material filled in the fine holes 41a of the anodized metal body (Al ₂ O ₃ ) 41 are the first metal material 70 and the second metal material 80 are designated as the resonance region X and the resonance region, respectively. W.

  The first metal material 70 and the second metal material 80 are the same as in the fifth embodiment. However, in this embodiment, materials having different dielectric constants are used at least in order to provide a difference in the optical path length of each resonance region due to the difference between these dielectric constants.

And the manufacturing method of the electric field enhancement optical device D11 by this embodiment starts from the metal body 40 (FIG. 11A), for example, and performs a porous type anodic oxidation process to a part of metal body (Al) 40, and is fine. An anodized metal body (Al ₂ O ₃ ) 41 having a hole 41a and a thickness d is formed (FIG. 11B), and a mask M is formed on the portion of the anodized metal body (Al ₂ O ₃ ) 41 to be the resonance region W. After forming (FIG. 11C), the first metal material 70 is filled in the fine holes 41a not covered with the mask M (FIG. 11D), and after removing the mask M, the remaining fine holes 41a are filled with the second metal material 80. (FIG. 11E), and then a plurality of metal fine particles B are fixed on the anodized metal body (Al ₂ O ₃ ) 41 (FIG. 11F).

  Hereinafter, the operation of the electric field enhancing optical device D11 according to the present embodiment will be described.

  By the method as described above, the electric field enhanced optical device D11 according to the present embodiment has the resonance wavelength of each of the translucent layers 20 in which the fine holes 41a are filled with metal materials having a thickness of d but different dielectric constants. It is constituted by different resonance regions W and resonance regions X, and the resonance width of the resonance wavelength is expanded as a whole.

  Therefore, also in this embodiment, the same effect as that of the fourth embodiment can be obtained.

Furthermore, in this embodiment, it is not necessary to provide a step in the resonator length. Therefore, it is possible to facilitate a process for ensuring the conductivity of the anodized metal body (Al ₂ O ₃ ) 41 in electroplating or the like. For example, it becomes easy to control the process of thinning the anodized metal body (Al ₂ O ₃ ) 41 at the bottom of the fine hole 41a.

<Seventh Embodiment>
FIG. 12 is a schematic cross-sectional view showing the electric field enhanced optical device having the microresonator structure according to the present embodiment. This embodiment is different from the fifth and sixth embodiments in that the difference in the optical path length of each resonance region is provided by the difference in the dielectric constant of the light transmitting layer 20 and the difference in the resonator length in each region. . Therefore, the description of the same elements as those of the fifth and sixth embodiments is omitted unless particularly necessary.

The electric field enhancing optical device D12 according to the present embodiment is formed in a complementary manner on a metal body (Al) 40 having a stepped structure and a stepped structure of the metal body (Al) 40, and has a thickness of d1 and d2. An anodized metal body (Al ₂ O ₃ ) 41 having a reverse staircase structure and having fine holes 41 a, a second metal material 80 filled in the fine holes 41 a in the resonance region W, and the resonance region The first metal material 70 filled in the micro holes 41a in X and a metal layer made of a plurality of metal fine particles B formed on the anodized metal body (Al ₂ O ₃ ) 41 is there. The resonance regions where the thickness of the anodized metal body (Al ₂ O ₃ ) 41 (translucent layer 20) is d1 and d2 are defined as a resonance region W and a resonance region X, respectively.

  The relationship between the material types of the first metal material 70 and the second metal material 80 and the dielectric constant is the same as in the fifth and sixth embodiments.

And the manufacturing method of the electric field enhancement optical device D12 by this embodiment performs the anodic oxidation process so that it may become a step-like structure with respect to the metal body (Al) 40, the micropore 41a is formed, and an anodized metal body The process until the surface of (Al ₂ O ₃ ) 41 is polished is the same as in the fifth embodiment. Then, the method of filling the second metal material 80 and the first metal material 70 into the fine holes 41a in the resonance region W and the resonance region X, respectively, is the same as in the sixth embodiment.

That is, for example, starting from the metal body 40, a mask is formed on the metal body 40 where the resonance region W is desired, and the thickness of the portion without the mask is d2-d1 (d2> d1) by dry or wet etching. After forming the metal body 40 so as to be thick, the mask is removed, and a part of the metal body (Al) 40 having a stepped structure is subjected to a porous type anodic oxidation treatment to obtain a thickness d2 having the fine holes 41a. anodized metal body _{(Al 2} O 3) 41 is formed, anodic-oxidized metal _{(Al 2} O 3) anodizing the metal body so as to form a portion where the thickness is d1 of 41 _(Al 2 _{O 3} ) 41 is polished, a mask is formed on the anodized metal body (Al ₂ O ₃ ) 41 in the resonance region W, the first metal material 70 is filled in the fine holes 41a not covered with the mask, and the mask is formed. Remaining fine after removal The electric field-enhanced optical device according to the present embodiment is obtained by filling the pores 41 a with the second metal material 80 and then fixing the plurality of metal fine particles B on the flat anodized metal body (Al ₂ O ₃ ) 41. D12 is obtained (FIG. 12).

  Hereinafter, the operation of the electric field enhancing optical device D12 according to the present embodiment will be described.

  By the method as described above, the electric field-enhanced optical device D12 according to the present embodiment has a step-like structure with thicknesses d1 and d2, and a light-transmitting light filled with metal materials having different dielectric constants in the micro holes 41a. The layer 20 includes a resonance region W and a resonance region X having different resonance wavelengths, and the resonance width of the resonance wavelength is expanded as a whole.

  Therefore, also in this embodiment, the same effect as that of the fourth embodiment can be obtained.

  Furthermore, in this embodiment, the difference in the optical path length of each resonance region is provided by the difference in the dielectric constant of the light-transmitting layer 20 and the difference in the resonator length in each region, so that the resonance wavelength with higher efficiency and accuracy can be obtained. Control becomes possible. This is because it is possible to largely control the resonance wavelength by providing a step in the resonator length, and by filling the fine hole 41a with a metal material such as Au or Ag and changing the dielectric constant in the light transmitting layer 20. This is because the resonance wavelength can be finely adjusted.

<Design changes>
In the above embodiments, the second reflective layer has been described as having reflectivity, but the problem in the present invention is solved even if the second reflective layer has transflective properties. In this case, it is arbitrary whether the measurement light enters from the first reflection layer or the second reflection layer, and it is also possible to enter the measurement light from both sides simultaneously using a plurality of light sources.

  FIG. 13A is a diagram showing a microresonator structure of an electric field-enhanced optical device according to the present invention and three comparative electric field-enhanced optical devices according to the present invention, and FIG. 13B shows a resonator structure of these electric field-enhanced optical devices. It is a figure which shows the comparison of an electric field enhancement intensity.

  The electric field-enhanced optical device according to the present invention has a metal layer having a stepped structure with a step height of 40 nm, an inverse stepped structure complementary to the shape of the metal layer, and a thickness of 220 nm and 260 nm. And a plurality of fine metal particles fixed on the dielectric layer. On the other hand, as a comparative device, a dielectric layer having a thickness of 220 nm, a thickness of 260 nm, and a device without a metal layer and having a resonator structure with the same configuration were used.

  As a result, as shown in FIG. 13, the electric field-enhanced optical device according to the present invention has the same configuration with the electric field enhancement strength, and the thickness of the dielectric layer is 220 nm or 260 nm. I understand that.

  The specific resonance width is obtained from the standard value of the electric field enhancement in FIG. 14, and the resonance widths of the dielectric layer having a thickness of 220 nm and 260 nm with the same configuration are 87 nm and 126 nm, respectively. The electric field enhanced optical device according to the invention was 194 nm.

  As described above, it is possible to expand the resonance width by providing a plurality of resonance regions in the microresonator structure so that optical resonance is possible for a plurality of wavelengths. Thus, in the optical measurement, it is not necessary to replace the electric field enhancing optical device with the change of the wavelength of the measurement light, and the optical measurement can be reduced in cost and simplified. Furthermore, for light having a wavelength width, light in a wider wavelength region can be used, and the efficiency of optical measurement can be improved.

Schematic perspective view showing a conventional electric field enhancing optical device D1 Schematic partial cross-sectional view showing a conventional electric field enhanced optical device D1 Schematic perspective view showing a conventional electric field enhanced optical device D2 Schematic perspective view showing an electric field enhancing optical device D3 according to the first embodiment Schematic perspective view showing an electric field enhancing optical device D4 according to the second embodiment Schematic perspective view showing an electric field enhancing optical device D5 according to the third embodiment Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D5 according to the third embodiment (Part 1) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D5 according to the third embodiment (No. 2) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D5 according to the third embodiment (No. 3) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D5 according to the third embodiment (No. 4) Schematic perspective view showing an electric field enhancing optical device D7 according to the fourth embodiment Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D7 according to the fourth embodiment (Part 1) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D7 according to the fourth embodiment (Part 2) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D7 according to the fourth embodiment (No. 3) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D7 according to the fourth embodiment (Part 4) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D7 according to the fourth embodiment (No. 5) Schematic perspective view showing a metal body having fine holes formed by anodization Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D10 according to the fifth embodiment (Part 1) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D10 according to the fifth embodiment (Part 2) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D10 according to the fifth embodiment (No. 3) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D10 according to the fifth embodiment (Part 4) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D10 according to the fifth embodiment (No. 5) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D10 according to the fifth embodiment (No. 6) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D11 according to the sixth embodiment (No. 1) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D11 according to the sixth embodiment (No. 2) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D11 according to the sixth embodiment (No. 3) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D11 according to the sixth embodiment (No. 4) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D11 according to the sixth embodiment (No. 5) Schematic partial sectional view showing the manufacturing process of the electric field enhanced optical device D11 according to the sixth embodiment (No. 6) Schematic sectional view showing an electric field enhanced optical device D12 according to a seventh embodiment Schematic partial cross-sectional view showing a microresonator structure of an electric field enhanced optical device and a comparative device according to the present invention in an embodiment The figure which shows the comparison of a resonator structure and an electric field enhancement intensity about an Example The figure which shows the comparison of a resonator structure and a resonance width about an Example

Explanation of symbols

10 first reflective layer 11 fine metal wire 12
20 translucent layer 30 second reflective layer 40 metal body 41 anodized metal body 41a microscopic hole 70 first filling metal material 80 second filling metal material B metal fine particles D1 to 5, 7, 10, 11 electric field enhanced light Device d · d1 · d2 Light transmission layer thickness L1 Measurement light L2
M mask W to Z resonance region W ′ to Z ′ micro resonance region

Claims (9)

A translucent layer having transparency, a first reflective layer having transflective properties formed on one surface of the translucent layer, and a reflective layer formed on the other surface of the translucent layer. An electric field-enhanced optical device having a microresonator structure composed of two reflective layers,
The microresonator structure has a plurality of resonance regions having different optical path lengths between the first reflective layer and the second reflective layer;
By irradiating the first reflective layer with measurement light from the side opposite to the light transmissive layer with respect to the first reflective layer, between the first reflective layer and the second reflective layer An electric field-enhanced optical device characterized by causing optical resonance in   The electric field-enhanced optical device according to claim 1, wherein the resonance region includes a plurality of minute resonance regions.   The electric field-enhanced optical device according to claim 2, wherein the microresonance region is disposed substantially uniformly in the microresonator structure.   4. The electric field enhanced optical device according to claim 1, wherein the optical path length varies depending on a difference in dielectric constant of the light transmitting layer in each of the resonance regions. 5.   5. The electric field-enhanced optical device according to claim 1, wherein the optical path length is different depending on a difference in resonator length between the resonance regions.   6. The electric field enhanced optical device according to claim 1, wherein the first reflective layer is made of a metal layer patterned on the surface of the translucent layer.   6. The electric field enhancement according to claim 1, wherein the first reflective layer is made of a metal layer formed by adhering a plurality of non-aggregated metal fine particles to the surface of the translucent layer. Optical device.   The electric field-enhanced optical device according to claim 1, wherein the translucent layer is composed of a microporous body having a plurality of micropores opened on the surface on the first reflective layer side.   The electric field-enhanced optical device according to claim 1, wherein the electric field-enhanced optical device resonates with the measurement light in a visible region to a near infrared region.

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