WO2012132982A1

WO2012132982A1 - Measurement device, measurement method using same, and method for producing measurement device

Info

Publication number: WO2012132982A1
Application number: PCT/JP2012/056971
Authority: WO
Inventors: 近藤　孝志; 誠治神波; 和大瀧川; 小川　雄一
Original assignee: 株式会社村田製作所
Priority date: 2011-03-31
Filing date: 2012-03-19
Publication date: 2012-10-04

Abstract

The present invention is a measurement device that is used for measuring the characteristics of a measurement subject using electromagnetic waves, and that is characterized by: being configured from a gap-disposing structure (11), which has a plurality of air gaps, and a holding film, which comprises a material that has the function of holding the measurement subject and transmits electromagnetic waves; and all or a portion of the gap-disposing structure (11) being embedded in the holding film.

Description

Measuring device, measuring method using the same, and manufacturing method of measuring device

The present invention relates to a measuring device used for measuring characteristics of an object to be measured using electromagnetic waves, a measuring method using the measuring device, and a manufacturing method of the measuring device.

Conventionally, in order to analyze the characteristics of a substance, the object to be measured is held in the gap arrangement structure, the electromagnetic wave is irradiated to the gap arrangement structure in which the object is held, and the transmission spectrum is analyzed. A measuring method for detecting the characteristics of an object to be measured is used. Specifically, for example, there is a technique of analyzing a transmission spectrum by irradiating a measurement object such as a dielectric film attached to a metal mesh filter with a terahertz wave.

As a conventional technique for analyzing a transmission spectrum using such an electromagnetic wave, Japanese Patent Application Laid-Open No. 2007-010366 (Patent Document 1) describes a void arrangement structure (for example, a metal mesh) in which void portions are arranged, and voids. There is disclosed a method for measuring characteristics of an object to be measured using an integrated structure including an arrangement member for arranging an object to be measured arranged on the surface of the arrangement structure. The object to be measured is held on the main surface of the arrangement member opposite to the void arrangement structure (FIG. 18 of Patent Document 1).

Similarly, Japanese Patent Application Laid-Open No. 2007-163181 (Patent Document 2) discloses a method for measuring characteristics of a measurement object using an arrangement member for arranging the measurement object arranged on the surface of a gap arrangement structure. Is disclosed. In Patent Document 2, as a method of closely attaching the gap arrangement structure and the arrangement member, a method of sucking the arrangement member toward the gap arrangement structure side is used (FIG. 11 of Patent Document 2).

In such a measurement method using electromagnetic waves, the characteristics of the object to be measured are measured by detecting changes in the frequency characteristics caused by the interaction of the electromagnetic field localized on the surface of the void-arranged structure with the object to be measured. is doing. Here, the electric field strength of the electromagnetic field generated by the electromagnetic wave irradiation is the strongest in the vicinity of the surfaces of both main surfaces of the void arrangement structure, and attenuates exponentially as the distance from the void arrangement structure increases. In the measurement method in which the object to be measured is held in the gap arrangement structure via the arrangement member, the object to be measured exists far away from the surface of the gap arrangement structure by the thickness of the arrangement member. The electric field strength at the position where the object is held becomes smaller than the surface of the void-arranged structure. Therefore, in this measurement method, the localized electromagnetic field cannot be used effectively, and the detection sensitivity is lower than when the object to be measured is arranged near the surface of the metal mesh.

In addition, as described in Patent Document 2, a special jig or device is required in the method of bringing the gap arrangement structure and the arrangement member into close contact with each other by sucking the arrangement member toward the gap arrangement structure. It is difficult to keep the degree of close contact constant, which causes an error in measurement results. Further, it is not possible to arrange the arrangement members on both main surfaces of the gap arrangement structure.

Note that Patent Document 1 also discloses a method of fixing an object to be measured on an inner surface of a void portion of a void arrangement structure without using an arrangement member. However, even if the solution containing the object to be measured is dropped onto the structure and the solution is flown so as to be fixed inside the gap, a vortex is generated near the main surface of the gap, and the object to be measured is fixed. There is a problem in that the position varies, or the solution tends to remain in the gap, and it is difficult to clean and replace the solution. Further, Patent Document 1 discloses a method of embedding a void portion of a void-arranged structure body with an object to be measured, but the thickness of the object to be measured is not necessarily constant, and voids having various depths corresponding to them. It is not realistic to prepare.

JP 2007-010366 A JP 2007-163181 A

In view of the above circumstances, the present invention provides a measuring device that can easily hold an object to be measured and can improve measurement sensitivity when measuring characteristics of the object to be measured using electromagnetic waves. With the goal.

The present invention is a measuring device used for measuring the characteristics of an object to be measured using electromagnetic waves,
A void arrangement structure having a plurality of voids;
It is made of a material that transmits the electromagnetic wave, and includes a holding film that has a function of holding the object to be measured.
In the measurement device, all or part of the void arrangement structure is embedded in the holding film.

The void arrangement structure is preferably made of a conductive material.
It is preferable that at least one main surface of the void arrangement structure is substantially parallel to at least one main surface of the holding film.

Further, the present invention holds the object to be measured in the measuring device,
By irradiating the measurement device holding the object to be measured with electromagnetic waves and detecting the frequency characteristics of the electromagnetic waves transmitted through the measurement device or the frequency characteristics of the electromagnetic waves reflected by the measurement device, It also relates to measuring methods for measuring properties of objects.

It is preferable that the object to be measured is held in an optical distance from the gap arrangement structure of 1/5 or less of the wavelength of the electromagnetic wave irradiated to the measurement device.

Further, the present invention is a method for manufacturing the above measuring device,
Arranging the void arrangement structure on one main surface of the holding film;
Heating the void arrangement structure,
And a step of embedding part or all of the void arrangement structure in the holding film.

The step of heating the void arrangement structure is preferably performed by a method of heating only the void arrangement structure.

According to the present invention, the measurement device can easily hold the measurement object and can be held near the void-arranged structure, and thus can detect a small amount of the measurement object by a simple method. Is provided. In addition, measurement reproducibility can be improved by suppressing variation in measurement.

In addition, since measurement errors due to the degree of adhesion between the gap arrangement structure and the holding film are unlikely to occur as in the case where the object to be measured is held via the holding film arranged on the gap arrangement structure, the measurement error is reduced. Can be reduced or eliminated.

Also, since a special jig or device for bringing the gap arrangement structure and the holding film into close contact with each other is not necessary, the device can be made small and inexpensive. Furthermore, the labor of attaching the holding film to the void-arranged structure at the time of measurement is unnecessary, and the measurement work is simple and easy.

It is a schematic diagram for demonstrating the outline | summary of the measuring method of this invention. It is a schematic diagram for demonstrating the intensity | strength of the electric field of the principal surface direction in a space | gap arrangement structure body (metal mesh). (A) is a front view which shows an example of the structure of this invention. (B) is a longitudinal sectional view taken along the BB plane of (a). (C) is a longitudinal cross-sectional view which shows another example of the structure of this invention. (D) is a longitudinal cross-sectional view which shows another example of the structure of this invention. It is a schematic diagram which shows an example of the manufacturing process of the measuring device of this invention. It is a schematic diagram which shows another example of the manufacturing process of the measuring device of this invention. It is a schematic diagram which shows another example of the manufacturing process of the measuring device of this invention. (A) is a perspective view which shows an example of the space | gap arrangement structure body used for this invention. (B) is a schematic diagram for demonstrating the lattice structure of a space | gap arrangement structure body. It is a schematic cross section for demonstrating an example of the installation state of the measuring device in this invention. 6 is a graph showing frequency characteristics obtained in Example 3. (A) is a frequency characteristic when the object to be measured is not held. (B) is a frequency characteristic when the object to be measured is held. 6 is a graph showing frequency characteristics obtained in Comparative Example 1. (A) is a frequency characteristic when the object to be measured is not held. (B) is a frequency characteristic when the object to be measured is held.

First, an outline of an example of the measurement method of the present invention will be described with reference to FIG. FIG. 1 is a diagram schematically showing the overall structure of a measuring apparatus used in the measuring method of the present invention. This measuring apparatus uses an electromagnetic wave (for example, a terahertz wave having a frequency of 20 GHz to 120 THz) generated by irradiating a semiconductor material with a laser beam irradiated from a laser 2 (for example, a short light pulse laser). It uses pulses.

In the configuration of FIG. 1, the laser beam emitted from the laser 2 is branched into two paths by the half mirror 20. One is irradiated to the photoconductive element 27 on the electromagnetic wave generation side, and the other is received through the time delay stage 26 by using a plurality of mirrors 21 (numbers with similar functions are omitted). The photoconductive element 28 on the side is irradiated. As the

photoconductive elements

27 and 28, a general element in which a dipole antenna having a gap portion in LT-GaAs (low temperature growth GaAs) is formed can be used. Further, as the laser 2, a laser using a solid such as a fiber type laser or titanium sapphire can be used. Furthermore, for the generation and detection of electromagnetic waves, the semiconductor surface may be used without an antenna, or an electro-optic crystal such as a ZnTe crystal may be used. Here, an appropriate bias voltage is applied by the power supply 31 to the gap portion of the photoconductive element 27 on the generation side.

The generated electromagnetic wave is made into a parallel beam by a paraboloidal mirror 22 and is irradiated to the plate-like periodic structure 1 by the paraboloidal mirror 23. The electromagnetic wave transmitted through the flat periodic structure 1 is received by the photoconductive element 28 by the

parabolic mirrors

24 and 25. The electromagnetic wave signal received by the photoconductive element 28 is amplified by the amplifier 34 and then acquired as a time waveform by the lock-in amplifier 32. Then, after signal processing such as Fourier transform is performed by a PC (personal computer) 33 including a calculating means, frequency characteristics such as a transmittance spectrum of the measuring device 1 are calculated. In order to acquire an electromagnetic wave signal by the lock-in amplifier 32, the bias voltage from the power source 31 applied to the gap of the photoconductive element 27 on the generation side is modulated by the signal of the oscillator 35. Thus, the S / N ratio can be improved by performing synchronous detection.

The measurement method described above is a method generally called terahertz time domain spectroscopy (THz-TDS).

FIG. 1 shows the case where the scattering is transmission, that is, the case where the electromagnetic wave transmitted through the measuring device is measured. In the present invention, “scattering” means transmission or backscattering as a form of forward scattering. It means a broad concept including reflection, which is one form, and is preferably transmission or reflection. More preferably, transmission in the 0th order direction or reflection in the 0th order direction.

In general, when the grating interval of the diffraction grating is s, the incident angle is i, the diffraction angle is θ, and the wavelength is λ, the spectrum diffracted by the diffraction grating is
s (sin i -sin θ) = nλ (1)
It can be expressed as. The 0th order of the “0th order direction” refers to the case where n in the above formula (1) is 0. Since s and λ cannot be 0, n = 0 holds only when sin i −sin θ = 0. Therefore, the “0th-order direction” means a direction where the incident angle and the diffraction angle are equal, that is, the direction in which the traveling direction of the electromagnetic wave does not change.

The electromagnetic wave used for such measurement is not particularly limited as long as it can cause scattering according to the structure of the void-arranged structure, such as radio waves, infrared rays, visible rays, ultraviolet rays, X-rays, gamma rays, etc. Either can be used. The frequency of the electromagnetic wave is preferably 1 GHz to 1 PHz, more preferably 20 GHz to 120 THz (terahertz wave), and most preferably 0.5 to 50 THz. Specific electromagnetic waves include, for example, a terahertz wave generated by the optical rectification effect of an electro-optic crystal such as ZnTe using a short light pulse laser as a light source, an infrared ray emitted from a high-pressure mercury lamp or a ceramic lamp, a semiconductor laser, and the like. Examples include infrared rays and visible light emitted from the laser and electromagnetic waves emitted from a photoconductive antenna.

In the present invention, “measuring the characteristics of an object to be measured” means performing various qualities such as quantification and dielectric constant of a compound to be measured, for example, a small amount of an object to be measured such as in a solution. The case of measuring the content of or the case of identifying the object to be measured. Specifically, there is a method in which the object to be measured is attached to the holding film constituting the measuring device of the present invention, and the characteristics of the object to be measured are measured using the measuring apparatus as described above.

Examples of objects to be measured include polymer films, paints, proteins, antigens, antibodies, ligands, DNA, cells, and the like.

In the present invention, the “void arrangement structure” is a structure having a plurality of voids, and is not particularly limited as long as it is a structure that generates a diffraction phenomenon when irradiated with an electromagnetic wave. Body and periodic structure. A quasi-periodic structure is a structure that does not have translational symmetry but is maintained in order. Examples of the quasi-periodic structure include a Fibonacci structure as a one-dimensional quasi-periodic structure and a Penroze structure as a two-dimensional quasi-periodic structure. A periodic structure is a structure having spatial symmetry as represented by translational symmetry, and a one-dimensional periodic structure, a two-dimensional periodic structure, or a three-dimensional periodic structure according to the symmetry dimension. Classified into the body. Examples of the one-dimensional periodic structure include a wire-grid structure and a one-dimensional diffraction grating. Examples of the two-dimensional periodic structure include a mesh filter and a two-dimensional diffraction grating. Among these periodic structures, a two-dimensional periodic structure is preferably used.

The gap arrangement structure is preferably made of a conductor material. The “conductor material” is an object (substance) that conducts electricity, and includes not only metals but also semiconductors. The conductor material preferably has a melting point equal to or higher than the softening temperature of the material constituting the holding film. Examples of the metal include gold, silver, copper, iron, nickel, and chromium, preferably gold, copper, nickel, and chromium, and more preferably gold and nickel. This is because it is relatively chemically stable and has high affinity with the object to be measured and the material that specifically extracts the object to be measured.

Examples of the semiconductor include a group IV semiconductor (Si, Ge, etc.), a group II-VI semiconductor (ZnSe, CdS, ZnO, etc.), a group III-V semiconductor (GaAs, InP, GaN, etc.), a group IV compound semiconductor ( SiC, SiGe, etc.), compound semiconductors such as I-III-VI group semiconductors (CuInSe ₂ etc.), and organic semiconductors. Si is preferable. This is because it is relatively chemically stable and has high affinity with the object to be measured and the material that specifically extracts the object to be measured.

The size of the gap portion of the gap arrangement structure is appropriately designed according to the measurement method, the material characteristics of the gap arrangement structure, the frequency of the electromagnetic wave used, etc., and it is difficult to generalize the range. When detecting forward scattered electromagnetic waves, it is preferable that the lattice spacing of the gaps indicated by s in FIG. 7B is not less than 1/10 and not more than 10 times the wavelength of the electromagnetic waves used for measurement. If the lattice spacing s of the gap is outside this range, the diffraction phenomenon is difficult to occur. Moreover, as a hole size of a space | gap part, it is preferable that the hole size of the space | gap part shown by d in FIG.7 (b) is 1/10 or more and 10 times or less of the wavelength of the electromagnetic waves used for a measurement. If the pore size of the gap is outside this range, the intensity of the electromagnetic wave scattered forward becomes weak and it becomes difficult to detect the signal.

Further, the thickness of the gap arrangement structure is appropriately designed according to the measurement method, the material properties of the gap arrangement structure, the frequency of the electromagnetic wave used, etc., and it is difficult to generalize the range, When detecting electromagnetic waves scattered forward, the wavelength is preferably several times less than the wavelength of the electromagnetic waves used for measurement. If the thickness of the structure is larger than this range, the intensity of the electromagnetic wave scattered forward becomes weak and it becomes difficult to detect the signal.

In addition, when using the space | gap arrangement structure which has a hole shape with high space symmetry as shown to Fig.7 (a), (b), the measuring device 1 is arrange | positioned diagonally with respect to the incident direction of electromagnetic waves. The angle formed between the normal direction of the measuring device 1 and the incident direction of the electromagnetic wave is preferably 1 to 89 °, more preferably 5 to 15 °. The characteristics of the device under test can be measured based on the fact that the position of the dip waveform generated in the frequency characteristics of the measured value due to such inclination changes due to the presence of the device under test.

When using a void arrangement structure having a hole shape with slightly low spatial symmetry, the measurement device 1 is preferably arranged perpendicular to the incident direction of the electromagnetic wave, and the normal direction of the measurement device 1 and the electromagnetic wave The angle formed with the incident direction is preferably 0 to 89 °, more preferably 0 to 10 °. The characteristics of the device under test can be measured based on the fact that the position of the dip waveform generated in the frequency characteristics of the measured value due to such an arrangement changes due to the presence of the device under test.

The “holding film” used in the present invention is a film-like member made of a material that transmits an electromagnetic wave irradiated to a measuring device and having a function of holding an object to be measured. The material that transmits electromagnetic waves is preferably a resin, silicon, ZnSe, or the like, and more preferably a thermoplastic resin. Specific examples include polycarbonate, cellulose, polyethylene, polypropylene, polyethylene terephthalate, polyvinylidene fluoride, nitrocellulose, polytetrafluoroethylene, polyethersulfone, and nylon.

The holding film “has a function of holding the object to be measured” means that, for example, the surface of the holding film itself has a binding property to the object to be measured, or the holding film is a porous body, a fibrous structure, or the like. This means that the object to be measured can be held in the voids (pores) and that a binding molecule (host molecule) that specifically adsorbs the object to be measured is bound to the holding film. Specific examples of the holding film include a membrane filter which is a porous film filter.

Such a holding film having a function of holding an object to be measured may lose the function of holding the object to be measured by heating. When such a holding film is used, a method of heating the holding film as much as possible ( For example, it is preferable to produce a measuring device by a method of heating only the void arrangement structure described later.

The measurement method using the electromagnetic wave as in the present invention is that the electromagnetic field localized on the surface of the void-arranged structure generated when the electromagnetic wave is irradiated causes a change in frequency characteristics by interacting with the object to be measured. We are using. Here, the electric field strength of the localized electromagnetic field is the strongest in the vicinity of the surfaces of the two principal surfaces of the gap arrangement structure, and further attenuates exponentially as the distance from the gap arrangement structure increases.

In the measuring device of the present invention, the product of the distance between the main surface of the holding film on which the object to be measured is held and the main surface on the side close to the object to be measured of the gap arrangement structure, and the refractive index therebetween. The optical distance (hereinafter referred to as “holding film thickness”) can be made zero or smaller than the attenuation distance of the localized electromagnetic wave. The “attenuation distance” is the distance between the position where the electric field strength attenuates and bottoms out as the distance from the gap arrangement structure increases, and the gap arrangement structure. For this reason, when measuring an object to be measured in the vicinity of the main surface on the side opposite to the void arrangement structure in the holding film, the localized electromagnetic field can be effectively utilized, Compared with the prior art in which the object to be measured is held on the body holding film, measurement sensitivity is improved, and measurement variations can be suppressed, so that highly reproducible measurement can be performed.

The thickness of the holding film alone in the measuring device of the present invention is preferably 1/5 or less of the wavelength λ of the electromagnetic wave irradiated to the measuring device, more preferably 12 minutes of the wavelength λ of the electromagnetic wave irradiated to the measuring device. 1 or less. At a position where the distance to the gap arrangement structure (distance from the main surface of the gap arrangement structure) is 1/5 of the wavelength λ of the electromagnetic wave to be irradiated, the attenuation of the electric field intensity almost bottoms out, and the wavelength lambda 12 This is because the attenuation of the electric field intensity becomes 1 / e at a position where 1 / (1 is a natural logarithm). Here, the “wavelength λ of the electromagnetic wave applied to the measuring device” means the wavelength of the electromagnetic wave that can localize the electromagnetic field on the surface of the void-arranged structure, and preferably 10 minutes of the lattice spacing of the void. Is an arbitrary wavelength in the range of the same length as 1 to 10 times, and more preferably corresponds to a maximum point in the transmittance spectrum or reflectance spectrum of the void-arranged structure, or a vicinity of a frequency where a minimum point appears. It is a wavelength.

As an example, FIG. 2 shows the electric field strength when only a metal mesh is irradiated with an electromagnetic wave having a wavelength of 300 μm. In FIG. 2, the horizontal axis indicates a value representing the distance from the main surface of the metal mesh as a ratio to the wavelength of 300 μm (zero on the horizontal axis corresponds to the main surface of the metal mesh). The plus direction on the horizontal axis corresponds to the outside of the metal mesh, and the minus direction corresponds to the inside of the metal mesh. In FIG. 2, 0.04 on the horizontal axis corresponds to 1/12 of the wavelength, and 0.2 corresponds to 1/5 of the wavelength. As shown in FIG. 2, at a position where the distance to the gap-arranged structure is 1/5 of the wavelength λ of the electromagnetic wave to be irradiated, the attenuation of the electric field intensity is almost bottomed out (e ^1/2 ), and the wavelength At a position that is 1/12 of lambda, the attenuation of the electric field intensity is 1 / e.

The measurement device of the present invention includes the measurement device, an irradiation unit that irradiates the measurement device holding the measurement object with electromagnetic waves, and a detection unit that detects the electromagnetic waves scattered by the measurement device. It can be used in a measuring device for measuring the characteristics of

Hereinafter, the present invention will be described in detail by embodiments, but the present invention is not limited to these embodiments.

(Embodiment 1)
The measuring device of this embodiment is shown in FIG. FIG. 3A is a front view, and FIG. 3B is a cross-sectional view along the BB plane. As shown in FIG. 3B, the entire void arrangement structure 11 is buried in one surface 121 of the holding film 12, and one main surface 111 of the void arrangement structure 11 is one of the holding films 12. The main surface 121 is substantially coplanar.

In this embodiment, when holding the object to be measured on the main surface 121 side of the holding film 12, the thickness of the holding film alone (the main surface 121 on the side of the holding film 12 on which the object to be measured is held and the gap arrangement structure 11 The distance from the main surface 111 on the side close to the object to be measured and the optical distance that is the product of the refractive index therebetween is substantially zero. Therefore, the localized electromagnetic field can be used effectively and the measurement sensitivity can be improved.

In addition, when the thickness of the holding film alone is set to zero, the solution containing the measurement object flowing on the main surface 111 of the gap arrangement structure 11 and the main surface 121 of the holding film 12 is difficult to stay, and is slightly washed. Can be replaced.

Further, by using a measurement device in which such a void arrangement structure and a holding film are integrated, measurement errors due to the degree of adhesion between the void arrangement structure and the holding film can be reduced or eliminated. In addition, since it is not necessary to closely attach the holding film to the void-arranged structure during measurement, the operation is simple and ready. Furthermore, since a jig or a device for bringing the gap arrangement structure and the holding film into close contact with each other is not necessary, the measuring device can be made small and inexpensive.

On the other hand, in this embodiment, the object to be measured may be held on the main surface 122 side of the holding film 12, and in this case, the thickness of the holding film alone (the main surface 122 on the side of the holding film 12 on which the object to be measured is held). And the optical distance which is the product of the refractive index between the main surface 112 on the side close to the object to be measured of the gap arrangement structure 11) is 5 minutes of the wavelength λ of the electromagnetic wave irradiated to the measuring device. It is preferably 1 or less, and more preferably 1/12 or less of the wavelength λ of the electromagnetic wave. Thereby, the localized electromagnetic field can be used effectively and the measurement sensitivity can be improved. Further, the main surface 122 on the side of the holding film 12 on which the object to be measured is held is generally parallel to the main surface 112 on the side close to the object to be measured of the gap arrangement structure 11. If not parallel, the measurement result is affected by the distribution of the amount of the object to be measured within the main surface 122 of the holding film 12, and the same applies to the other embodiments.

In the measurement device shown in FIG. 3C, a part of the void-arranged structure 11 is buried in one surface 121 of the holding film 12. Such a measuring device is also included in the measuring device of the present invention.

In the measuring device shown in FIG. 3C, when the object to be measured is held on the main surface 121 side of the holding film 12, the thickness of the holding film alone (the main surface on the side of the holding film 12 on which the object to be measured is held). 121 and a distance between the main surface 111 on the side close to the object to be measured of the gap arrangement structure 11 and an optical distance that is a product of the refractive index therebetween) are 5 minutes of the wavelength λ of the electromagnetic wave irradiated to the measuring device. Is preferably 1 or less, more preferably 1/12 or less of the wavelength λ of the electromagnetic wave. On the other hand, when the object to be measured is held on the main surface 122 side of the holding film 12, the thickness of the holding film alone (the main surface 122 on the side of the holding film 12 on which the object to be measured is held, and the object to be measured on the gap arrangement structure 11). The distance from the main surface 112 on the side close to the object to be measured is preferably 1/5 or less of the wavelength λ of the electromagnetic wave irradiated to the measuring device, and is 1/12 or less of the wavelength λ of the electromagnetic wave. Is more preferable.

By using such a measuring device, not only the surface inside the gap but also the space inside the gap can be fixed, and the measurement sensitivity is improved. In the measuring device shown in FIG. 3D, the void arrangement structure 11 is buried inside the one surface 121 of the holding film 12. Such a measuring device is also included in the measuring device of the present invention.

Further, in the present invention, for example, the measurement object is held on both main surfaces of the measurement device by using a measurement device in which the void arrangement structure is embedded in the center in the thickness direction in the holding film having a larger thickness. As a result, a larger number of objects to be measured can be held near the surface of the void-arranged structure, and the measurement sensitivity can be further improved. Conventionally, as in Patent Document 2, when the gap arrangement structure and the arrangement member are brought into close contact with each other by sucking the arrangement member toward the gap arrangement structure, holding films are arranged on both main surfaces of the gap arrangement structure. I couldn't. Further, the operation of bringing the two holding films into close contact with both surfaces of the void-arranged structure at the time of measurement is very complicated.

Holding the object to be measured on the main surface 121 or the main surface 122 side of the holding film 12 is not only the case where the object to be measured is held on the main surface of the holding film 12, but the holding film 12 is, for example, a porous body. This is a concept that includes the case where it is held in the pores (that is, inside the holding film 12). Even in the latter case, it is preferable that the object to be measured be held in a range in which the optical distance from the void-arranged structure is one fifth or less of the wavelength of the electromagnetic wave irradiated to the measurement device.

<Manufacturing method 1>
An example of the manufacturing method of the measuring device of this invention is shown in FIG. Each process for manufacturing a measuring device is as follows. In addition, this manufacturing method is a manufacturing method suitable for manufacturing the measurement device of Embodiment 1.

(A) Step of disposing the void arrangement structure on one main surface of the holding film First, the void arrangement structure is arranged on one main surface of the holding film. As the arrangement method, a separately prepared void arrangement structure may be arranged on the holding film. Further, the void arrangement structure may be formed on the holding film by printing.

(B) Step of heating void arrangement structure and holding film Next, the void arrangement structure and the holding film are heated. Heating may be performed simultaneously with the next step (c) as necessary. The heating is preferably performed so that the temperature of the void-arranged structure reaches the softening temperature of the constituent material of the holding film. Alternatively, the void arrangement structure may be heated separately, and the heated void arrangement structure may be arranged on the holding film.

As the heating method, it is preferable to use a method of heating only the void arrangement structure. That is, it is preferable to use a heating method that does not directly heat the holding film. Examples of such a heating method include a method of irradiating the gap arrangement structure with electromagnetic waves and a method of grounding the gap arrangement structure and applying corona discharge to the gap arrangement structure.

By using such a heating method, even when the holding film loses the function of holding the object to be measured by heating, it retains the function of holding the object to be measured except for the portion in contact with the gap arrangement structure. can do. “The function of holding the object to be measured is impaired by heating” means, for example, that when the holding film is a porous body, a fibrous structure, etc., and the object to be measured is held in the void, This means that the object to be measured cannot be held by filling the gap portion. As another example, when a binding molecule (host molecule) that specifically adsorbs an object to be measured is bound to a holding film, the host molecule is denatured by heating so that the object to be measured cannot be held. Cases.

In the present manufacturing method shown in FIG. 4, heating of the void-arranged structure is performed by irradiating electromagnetic waves (preferably microwaves, more preferably electromagnetic waves having a frequency of about 2.45 GHz). At this time, the electromagnetic wave is mainly absorbed in the void arrangement structure (metal thin film), and only the void arrangement structure is subjected to juule heating. Only the periphery of the void-arranged structure of the holding film can be heated by this heat, and can be embedded with a small amount of pressure in the next step. In addition, since the main part of the holding film (the part where the object to be measured is held) is hardly heated, the physical characteristics of the holding film can be maintained in this step.

(C) Step of Embedding Void Arrangement Structure in Retention Film Next, in this manufacturing method, the entire void arrangement structure is embedded in the retention film. As the embedding method, a method of applying pressure from the outside to the void arrangement structure and the holding film is preferable. In this manufacturing method, as shown in FIG. 4, the holding film 12 and the gap arrangement structure 11 arranged thereon are passed between the two rollers 4 to thereby hold the gap arrangement structure and the holding structure. Pressure from the outside (pressures opposite to each other) is applied to the membrane.

(D) Step of cooling the gap arrangement structure Finally, the measurement device of the present invention can be obtained by cooling the gap arrangement structure. As a cooling method, various methods such as natural cooling and forced cooling can be appropriately used.

<Manufacturing method 2>
Another example of the manufacturing method of the measuring device of the present invention is shown in FIG. The manufacturing method of this embodiment is the same as that of the said manufacturing method 1 except using a corona discharge instead of irradiating electromagnetic waves in the process (b) of the said manufacturing method 1. FIG. This manufacturing method is also a preferable manufacturing method for manufacturing the measurement device of the first embodiment.

In this case, it is necessary to ground the gap-arranged structure 11 in order to heat resistance by flowing electrons from the electrode 5 in a direct current. In this case, the corona discharge is also applied to the holding film, but since no current flows through the holding film, a substantial temperature rise of the holding film does not occur.

Note that, instead of performing corona discharge, the gap arrangement structure may be Joule-heated by passing a current through the gap arrangement structure. In this case, it is necessary to connect the gap arrangement structure 11 to the power source, but since no current flows through the holding film, a substantial temperature rise of the holding film does not occur.

<Manufacturing method 3>
FIG. 6 shows still another example of the measuring device manufacturing method of the present invention. In this manufacturing method, processes such as a photoresist manufacturing process, sputtering, and lift-off are used. The manufacturing procedure of the measuring device is as follows.

(A) A positive photoresist film is deposited on the entire holding film 12, and ultraviolet light is irradiated through a mask (not shown) that shields a portion corresponding to the void portion of the void arrangement structure. After the exposure, the remaining portion is dissolved to form a photoresist film 6.

(B) Using the photoresist film 6 as a mask, the holding film 12 is dry-etched using oxygen-based plasma.

(C) A metal such as Ni is sputtered to form the

metal films

110a and 110b.
(D) Measurement having a structure in which the gap arrangement structure 11 shown in FIG. 6D is embedded in the holding film 12 by dissolving the photoresist film 6 and lifting off the metal film 110b on the photoresist film 6. Device 1 is obtained. The completed drawing of FIG. 6 (d) has the same form as FIG. 3 (b), but by controlling the etching depth in step (b) and the sputter thickness in step (c), FIG. The structure of FIG. 3D can also be produced.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

Example 1
In this example, the structure of the present invention was manufactured by a method corresponding to the manufacturing method 1 described above. Specifically, the production was performed according to the following procedure.

First, a separately prepared void arrangement structure was arranged on the main surface of a holding film (polycarbonate film) having a thickness of 50 μm so that the main surfaces face each other. The void arrangement structure is made of Ni and has a shape as shown in FIG. 7 (the void size d is 180 μm, the lattice spacing (pitch) is 260 μm, and the thickness is 20 μm).

Irradiate electromagnetic waves with a frequency of 2.45 GHz for 3 minutes, confirm that the gap arrangement structure has become sufficiently hot, and sandwich the holding film and the gap arrangement structure with two high-rigidity metal plates. Then, pressure from the outside (pressures opposite to each other) was applied to the void arrangement structure and the holding film. In the state where the distance between the two high-rigidity metal plates was 50 μm, the film was left for several hours and naturally cooled, and then the holding film with the void-arranged structure embedded therein was taken out from the vise.

As a result, a measuring device as shown in FIG. 3B in which the void arrangement structure 11 was buried in one surface 121 of the polycarbonate film 12 was obtained. Note that the one main surface 111 of the void arrangement structure 11 was substantially flush with the one main surface 121 of the holding film 12. When the measurement object is held on the main surface 121 of the holding film 12 at the time of measurement, the distance between the main surface of the void arrangement structure and the measurement object (distance in the normal direction of the main surface) is approximately 0 μm. It becomes. When the object to be measured is held on the main surface 122 of the holding film 12, the distance between the main surface of the void arrangement structure and the object to be measured (distance in the normal direction of the main surface) is 30 μm.

(Example 2)
First, a separately prepared void arrangement structure was arranged on the main surface of a holding film (polycarbonate film) having a thickness of 50 μm so that the main surfaces face each other. The void arrangement structure is made of Ni and has a shape as shown in FIG. 7 (the void size d is 180 μm, the lattice spacing (pitch) is 260 μm, and the thickness is 20 μm).

After irradiating an electromagnetic wave with a frequency of 2.45 GHz for 3 minutes and confirming that the void structure was sufficiently heated, the second surface was further formed on the main surface opposite to the polycarbonate film of the void structure. The void arrangement structure was arranged so that the structure patterns overlapped. Next, the holding film and the two gap arrangement structures are sandwiched between two high-rigidity metal plates, and pressure is applied to the second gap arrangement structure and the holding film from the outside (pressures opposite to each other) using a vise. ) Was added. The interval between the high-rigidity metal plates was 80 μm. After leaving it to cool for a few hours, it was removed from the vise and the second void-arranged structure was removed.

As a result, as shown in FIG. 3D, the measurement device 1 in which the void arrangement structure 11 was buried about 10 μm inside from one main surface 121 of the holding film 12 was obtained. One main surface 111 of the void arrangement structure 11 is substantially parallel to one main surface 121 of the polycarbonate film 12. When the measurement object is held on the main surface 121 of the holding film 12 at the time of measurement, the distance between the main surface of the void arrangement structure and the measurement object (distance in the normal direction of the main surface) is about 10 μm. It becomes. When the object to be measured is held on the main surface 122 of the holding film 12, the distance between the main surface of the void arrangement structure and the object to be measured (distance in the normal direction of the main surface) is 20 μm.

(Example 3)
For the measuring device of the present invention, simulation calculation of the frequency characteristics of transmitted electromagnetic waves was performed using an electromagnetic field simulator MicroStripes (manufactured by CST). In this example, a measurement device in which a void arrangement structure is arranged (embedded) in the center in the thickness direction of a holding film (dielectric film having a relative dielectric constant of 1.1, a dielectric loss tangent of 0, and a thickness of 25 μm) is targeted. . As the void arrangement structure, a structure having square holes (voids) arranged in a square lattice as shown in the schematic diagram of FIG. 7 and formed entirely of metal (complete conductor) was used. The lattice spacing (s in FIG. 7B) of this void arrangement structure is 260 μm, the hole size (d in FIG. 7B) is 180 μm, and the thickness is 20 μm.

As shown in FIG. 8, the X-axis direction and the Y-axis direction in FIGS. 7 and 8 are used for the measuring device installed at the center between the two

ports

71 and 72 arranged at an interval of 460 μm. Periodic boundary conditions were given to, and simulation of frequency characteristics was performed. The distance between the port 71 and the center of gravity 114 of the gap arrangement structure constituting the measuring device 1 is 230 μm. Further, the distance between the port 72 and the center of gravity 114 of the gap arrangement structure constituting the measuring device 1 is also 230 μm. The port 71 is an electromagnetic wave emitting member, and both ports are light quantity measuring members. The polarization direction of the incident electromagnetic wave is the Y-axis direction in FIGS. 7 and 8, and the polarization direction of the electromagnetic wave detected at each port is also set to the Y-axis direction. The incident angle was vertical (θ = 0 degree shown in FIG. 8).

Separately, regarding the frequency characteristics when an object to be measured (relative dielectric constant 2.4, dielectric loss tangent 0.01, thickness 10 μm) is held (adhered) on one main surface of the measuring device (holding film). The same simulation calculation was performed.

FIG. 9 shows the frequency characteristics of the transmitted electromagnetic wave obtained by the above calculation. FIG. 9A shows the frequency characteristics of only the measurement device in which the void arrangement structure is arranged in the center in the thickness direction of the holding film. FIG. 9B shows a structure in which a void-arranged structure is disposed in the center in the thickness direction of a similar holding film, and a measured object (relative permittivity 2.4, dielectric loss tangent 0.01, This is a frequency characteristic when a thickness of 10 μm) is held (adhered). When FIG. 9A is compared with FIG. 9B, the peak of the transmittance spectrum is shifted to the low frequency side by 90.5 GHz due to adhesion of the measurement object.

(Comparative Example 1)
Instead of the measurement device of Example 3, except for the one in which a holding film (dielectric film having a relative dielectric constant of 1.1, a dielectric loss tangent of 0, and a thickness of 25 μm) is adhered to the main surface of the void arrangement structure In the same manner as in Example 3, a frequency characteristic simulation calculation was performed. The void arrangement structure is the same as that in the third embodiment.

Fig. 10 shows the frequency characteristics obtained by calculation. FIG. 10A shows the frequency characteristics of only those in which the holding film is in close contact with the main surface of the void arrangement structure. FIG. 10B shows the frequency characteristics when the object to be measured (relative dielectric constant 2.4, dielectric loss tangent 0.01, thickness 10 μm) is further adhered to the main surface of the holding film opposite to the void arrangement structure. It is. When both were compared, the peak of the transmittance spectrum was shifted to 31.8 GHz toward the low frequency side due to adhesion of the measurement object.

As can be seen from the above results, the measurement sensitivity of the measurement object is higher in Example 3 using the measurement device of the present invention than in Comparative Example 1, because the transmittance spectrum shifts due to the presence of the measurement object. Can be improved.

It should be considered that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 measurement device, 11 void arrangement structure, 110a, 110b metal film, 111, 112 main surface of void arrangement structure, 113 void portion, 114 center of gravity, 12 holding film, 121, 122 main surface of holding film, 2 layer The 20 half mirror, 21 mirror, 22, 23, 24, 25 parabolic mirror, 26 time delay stage, 27, 28 photoelectric conducting element, 31 power supply, 32 lock-in amplifier, 33 PC ( (Personal computer), 34 amplifier, 35 oscillator, 4 roller, 5 electrode, 6 photoresist film, 71, 72 ports.

Claims

A measuring device used for measuring characteristics of an object to be measured using electromagnetic waves,
A void arrangement structure (11) having a plurality of voids;
It is made of a material that transmits the electromagnetic wave, and includes a holding film that has a function of holding the object to be measured.
A measuring device, wherein all or part of the void arrangement structure (11) is embedded in the holding film.
The measurement device according to claim 1, wherein the gap arrangement structure (11) is made of a conductive material.
The measuring device according to claim 1, wherein at least one main surface of the void arrangement structure (11) is substantially parallel to at least one main surface of the holding film.
Holding the object to be measured in the measuring device according to claim 1;
Irradiating the measurement device holding the object to be measured with electromagnetic waves,
Detecting electromagnetic waves scattered by the measuring device,
A measurement method for measuring the characteristics of an object to be measured from the frequency characteristics of detected electromagnetic waves.
The measurement according to claim 4, wherein an object to be measured is held in an optical distance from the gap arrangement structure (11) within a range of 1/5 or less of a wavelength of an electromagnetic wave applied to the measurement device. Method.
A method for manufacturing a measuring device according to claim 1,
Arranging the void arrangement structure (11) on one main surface of the holding film;
Heating the void-arranged structure (11);
And a step of embedding a part or all of the void arrangement structure (11) in the holding film.
The method for manufacturing a measuring device according to claim 6, wherein the step of heating the gap arrangement structure (11) is performed by a method of heating only the gap arrangement structure (11).