JP2002148187A - Optical waveguide type spr phenomenon measuring chip, manufacturing method for it and spr phenomenon measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an SPR phenomenon measuring chip small-sized and convenient to be replaced, a manufacturing method for it, and an SPR phenomenon measuring method by using optical waveguide manufacturing technology having high flexibility and productivity. SOLUTION: This optical waveguide type SPR phenomenon measuring chip is provided with an optical waveguide and a metal thin film 6 at least a part of which is brought into direct contact with a core 9 and which causes a surface plasmon resonance phenomenon. In this SPR phenomenon measuring apparatus, a sample, the surface palsmon resonance phenomenon of which is measured by measuring light transmitted through the core is disposed in direct contact with the metal thin film. This SPR phenomenon measuring method is characterized similarly to the above. Accordingly, the optical waveguide type SPR phenomenon measuring chip is small-sized and convenient to be replaced, and allowed to be easily provided with various functions such as a sensor capable of simultaneously measuring plural portions, a multi-channel sensor capable of detecting plural samples and so on.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical waveguide type SPR phenomenon measuring chip, a method for manufacturing the same, and a method for measuring the SPR phenomenon. Waveguide type SPR phenomenon measuring chip capable of guiding light to a measurement surface in surface plasmon resonance (SPR) phenomenon measurement capable of performing quantitative and qualitative measurement of SPR phenomenon, and SPR phenomenon using the SPR phenomenon measuring chip Related to measurement method.

[0002]

2. Description of the Related Art Conventionally, measurement utilizing a color reaction or an immune reaction has been performed in chemical process measurement, environmental measurement, clinical examination, and the like. However, in this measurement method, there is a problem that an object to be measured needs to be extracted, and there are problems such as complicated operations and a need for a labeling substance. As a sensor capable of qualitative and quantitative measurement of a substance, a sensor using the photoexcitation surface plasmon resonance phenomenon has been proposed and put into practical use. Hereinafter, Surface Plasmon Resonance (Surface Plasmon Resonance)
e) is abbreviated as SPR.

[0003] As shown in FIG. 22, an SPR phenomenon measuring apparatus uses a polarizing plate 2 for passing light emitted from a light source 1 through only p-polarized light.
Is incident on the high-refractive-index prism 4 with an incident angle range, which is the lens 3, and irradiates the metal thin film 5 having the sensor film in contact with the object 6 to be measured. Is generally detected by the photoelectron detector 7 through the prism 4.

The light emitted from the light source 1 becomes an evanescent wave at the interface between the prism and the metal, and its wave number is obtained by the following equation.

[0005] k _ev = where k _p n _p sinθ, k _p is the incident light wave number, n _p is the refractive index of the prism,
θ is the angle of incidence.

On the other hand, a surface plasmon wave is generated on the surface of the metal thin film, and its wave number is obtained by the following equation.

K _sp = (C / ω) √ (εn ² / (ε + n ² )) where C is the speed of light, ω is the angular frequency, ε is the dielectric constant of the metal thin film, and n is the refraction of the measured object. Rate.

When the wave number of the evanescent wave coincides with the wave number of the surface plasmon wave at the incident angle θ or the wave number of the incident light, the evanescent wave is used for exciting the surface plasmon, and the amount of light observed as reflected light decreases.

In FIG. 22, light emitted from the light source 1 is always incident on the lens 3 through a lens 3 with light having a certain incident angle range. In many cases, the type 1 and the photoelectron detector 7 can be driven while maintaining a constant reflection angle (see the arrow in FIG. 22).

[0010] Alternatively, as shown in FIG. 23, there is a type in which the angle of incident light is fixed and the wave number of the incident light is variable, or a type in which reflected light can be separated. In FIG. 23, reference numerals indicate the same as those in FIG.

Since the SPR phenomenon depends on the refractive index of the object to be measured in contact with the prism / metal thin film, for example, when a sample is taken as water and measured with an SPR measuring apparatus having a configuration as shown in FIG. As described above, it can be detected as a curve having a minimum at a certain angle, and by not only measuring the change in the refractive index due to the change in the concentration of the DUT 6, but also immobilizing the antibody or the like on the metal thin film 5, The specific substance can be quantified by measuring the change in the refractive index of the antibody bound to the antigen.

In recent years, there has been an increasing demand for miniaturization of the SPR phenomenon measuring apparatus. However, the apparatus configuration as shown in FIG. 22 has the drawback that the device becomes large due to the presence of the movable part, and that it is very inconvenient to replace the metal thin film 5 mainly in the measurement part.

Therefore, a fiber type SPR phenomenon measuring apparatus (product name: Biacore) was supplied by Biacore.
re Probe), Texas Instruments (Te
Xas Instrument) sells a small SPR phenomenon measuring device (product name Spreeta) in which a light source, a photoelectron detector, a polarizing plate, and a metal thin film are arranged in an epoxy resin. Also, various other small SPR phenomenon measuring devices have been proposed.

However, most of the fiber type has a metal thin film for measurement formed on its end face, which is difficult to process, and can have only one measurement surface per fiber. Further, optical components such as a splitter and a coupler for extracting reflected light from the end face are required. For those with all optical systems on epoxy resin, etc.,
All the optical components must be arranged with high precision, and the convenience of replacing the metal thin film is lost.

[0015]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and its object is to provide a general-purpose device.
An object of the present invention is to provide a small-sized and easily replaceable SPR phenomenon measuring chip, a manufacturing method thereof, and a SPR phenomenon measuring method using an optical waveguide manufacturing technique having high productivity.

[0016]

In order to solve the above problems, an optical waveguide type SPR phenomenon measuring chip according to the present invention comprises:
A core and a clad provided around the core,
The core has a higher refractive index than the cladding, an optical waveguide for confining and propagating light incident on the core, and a metal thin film that at least partially directly contacts the core and causes a surface plasmon resonance phenomenon. Provided optical waveguide type SP
An R phenomenon measuring chip, wherein a sample whose surface plasmon resonance phenomenon is measured by measuring light propagating through the core is provided so as to contact the metal thin film.

Further, in the method of manufacturing an optical waveguide type SPR phenomenon measuring chip according to the present invention, a groove having a desired shape for forming a core is formed in a transparent clad substrate, and the groove is formed in the groove more than the clad material substrate. Forming a core with a high refractive index, forming a metal thin film that causes the surface plasmon resonance phenomenon on it, and forming an over cladding with a lower refractive index than the core in the part excluding the metal thin film part I do.

A second method for manufacturing an optical waveguide type SPR phenomenon measuring chip according to the present invention comprises the steps of:
A core having a desired shape and a refractive index higher than that of the clad is formed, a clad is formed so as to have the same height as the core, and a metal thin film that causes a surface plasmon resonance phenomenon is formed thereon. An over clad having a lower refractive index than the core is formed in a portion other than the portion.

A third method of manufacturing an optical waveguide type SPR phenomenon measuring chip according to the present invention is to form an easily dissolvable sacrificial layer on a substrate having an optical flat surface, and to form a sacrificial layer having a desired shape on the sacrificial layer. Also form a core with a high refractive index, form a clad on it thicker than the core, immerse it in a solution that dissolves the sacrifice layer, dissolve the sacrifice layer, remove the substrate with an optical plane, remove the core A metal thin film that causes a surface plasmon resonance phenomenon is formed on the surface where is exposed, and overcladding having a lower refractive index than the core is formed in a portion excluding the metal thin film portion.

A feature of the present invention resides in that an optical waveguide is applied to an SPR phenomenon measuring chip. Using optical waveguide fabrication technology, many waveguide cores can be fabricated on one chip,
Various functions such as branching on the way can be provided, and it is possible to manufacture a large number of such SPR phenomenon measurement chips at low cost.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The principle of the SPR phenomenon measurement according to the present invention is an application of the type shown in FIG. 23, and uses an optical waveguide instead of a prism to measure a spectrum.

FIG. 1 is a schematic view of an SPR phenomenon measuring chip using an optical waveguide. The optical waveguide is a linear waveguide core 9
And a structure in which a clad 8 and an over clad 10 having a lower refractive index than the core 9 are provided around the core 9. The metal thin film 5 that causes the surface plasmon resonance phenomenon is formed in a part of the core 9 so as to be in direct contact with the core 9, and this part becomes a measurement surface. The incident light 11 enters the core 9, causes the SPR phenomenon with the sample 6 on the measurement surface, and is emitted as the emitted light 12. The SPR phenomenon can be observed by measuring the change in the amount of emitted light or the change in the spectrum.

When an SPR phenomenon measuring chip as shown in FIG. 1 is manufactured, a groove 13 for forming a core in the clad 8 is formed as shown in FIG. (FIG. 2B), and a metal thin film 5 causing a surface plasmon resonance phenomenon is formed thereon (FIG. 2C). The metal thin film 5 has only to form the core 9 at least partially, and may be formed over the entire clad 8. S at this stage
Although it is possible to measure the PR phenomenon, it is desirable to form a recess for mounting a sample with the over clad 10 (FIG. 2).
(D)).

Further, as shown in FIG. 3, a core 9 is formed on the clad 8 (FIG. 3A). Then core 9
The cladding 8 is formed to the same height as that of FIG. 3 (FIG. 3B).
After that, a metal thin film 5 is formed (FIG. 3C), and a recess for mounting a sample is formed.

Further, as shown in FIG. 4, a chromium film (sacrifice layer) 15 of about 1 μm is formed on a smooth substrate 14 (FIG. 4A), and a core 9 is formed thereon (FIG. 4A).
(B)). A clad 8 is formed thereon (FIG. 4)
(C)) The chromium film (sacrifice layer) 15 is melted and the substrate 14 is melted.
Is peeled off (FIG. 4D). It can also be manufactured by forming the over clad 10 thereon except for the measurement region and forming the metal thin film 5.

The method of obtaining a core or a clad having a desired shape is as follows: (1) a method of forming a core or a clad, followed by cutting with a dicing saw or a drill;
A method of applying a resist after forming a core or a clad, curing the resist only at a desired portion, removing an uncured portion, and etching a core and a clad to remove a portion without a resist; A) A method in which a photosensitive material is used for the core or the clad, the material is applied to a substrate or put into a reservoir, light is directly irradiated through a mask or directly, and the non-irradiated portion is removed with a solvent.

In the above method (3), the photosensitive substance is a photosensitive polyimide-based, epoxy-based, acrylic-based, silicone-based oligomer or monomer.

As the above-mentioned polyimide photosensitive material,
For example, a polyimide-based oligomer or monomer represented by the following structural formula 1 can be given as an example.

Structural formula 1

Embedded image (In the formula, R ₁ is a bisalkyl- or bisperfluoroalkyl-benzene, R ₂ is an alkyl, alkylphenylene, perfluorophenylene group, and R ₃ is an alkyl group or a fluoroalkyl group.) In addition, the above-mentioned polyimide system As the photosensitive substance, for example, an epoxy oligomer or a monomer represented by the following structural formula 2 can be exemplified.

Structural formula 2

Embedded image (Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkyl group, an alkoxy group, or a trifluoromethyl group, X ₁ , X ₂ , and X ₃ are linking groups, and Y is an epoxy group. Group or

[0031]

Embedded image Further, as the above-mentioned acrylic photosensitive substance, for example, an acrylic oligomer or monomer represented by the following structural formula 3 can be exemplified.

Structural formula 3

Embedded image (Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkyl group, an alkoxy group or a trifluoromethyl group, X ₁ , X ₂ , and X ₃ represent a linking group, and Y represents an acryl group. Group or methacryl group.

Further, as the above-mentioned silicone-based photosensitive substance, for example, a silicone-based oligomer or monomer represented by the following structural formula 4 can be exemplified.

Structural formula 4

Embedded image (In the formula, X represents a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, or an alkoxy group, m represents an integer of 1 to 4. x and y show the abundance ratio of each unit. R ₁ and R ₂ represent a methyl group, an ethyl group, or an isopropyl group, and R ₁ and R ₂ may be the same.) Molecularization is performed by crosslinking an epoxy group contained in the component represented by the structural formula by a light bond between reactive groups such as a hydroxyl group. It is desirable to add a photopolymerization initiator in order to cause the crosslinking reaction efficiently and sufficiently.
Representative photopolymerization initiators include cationic photopolymerization initiators such as sulfonium salts and osmium salts.

The polymerization of the silicone-based photosensitive material of the present invention includes the case where a photosensitive agent reacts with an oligomer and a monomer. Azide compounds such as azidopyrene, 4,4-diazidobenzalacetone, 2,6
-Di- (4'-azidobenzal) cyclohexanone,
Bisazide compounds and diazo compounds such as 2,6-di- (4′-azidobenzal) -4-methylcyclohexanone are typical.

The polymerization of the acrylic photosensitive material of the present invention is carried out by the reaction of a photosensitive agent with an oligomer and a monomer. Photosensitizers include diphenyltriketone benzoin, benzoin methyl ether, benzophenone, acetophenone,
Carbonyl compounds such as diacetyl, peroxides such as benzoyl peroxide, azo compounds such as azobisisobutyronitrile, azide compounds such as azidopyrene, 4,4′-diazidobenzalacetone, 2,6-di- ( Representatives are bisazide compounds and diazo compounds such as 4'-azidobenzal) cyclohexanone and 2,6-di- (4'-azidobenzal) -4-methylcyclohexanone.

The shape of the core of the optical waveguide can be variously changed by changing the pattern of the mask.

As shown in FIG. 5, it is possible to form a core which is bent into a U-shape as shown in FIG. Further, as shown in FIG. 7, the core 9 may be formed up to the right end of the clad 8, and the metal thin film 5 may be formed in contact with the core 9.

Hereinafter, 16 regions (shown by broken lines) in FIGS. 5 and 6 are assumed to be metal thin films, but are transparently illustrated for the sake of explanation. The metal thin film 16 only needs to be in contact with the core 9, and the shape and size are not particularly limited. In FIG. 5 and thereafter, the overcladding 10 is omitted to facilitate understanding of the shape of the core.

When connecting an SPR phenomenon measuring chip, which will be described later, to a light source / photodetector, two points of the incident light 11 and the outgoing light 12 must be connected in FIG. The use of an optical fiber and an optical fiber array for input / output of light has the advantage that optical connection can be made at one location when the core shape is as shown in FIG.

As shown in FIG. 8, a large number of cores can be formed. Metal thin film 1 formed on each core 9
6a, 16b, and 16c, respectively, react with certain substances A, B, and C to form metal thin films 16a, 16b, and 16c, respectively.
If the above-mentioned sensor films that change the refractive index are fixed, if the substance A is contained in the sample, a change occurs in the SPR phenomenon occurring on the metal thin film 16a. Thus, it can be used as a multi-channel sensor capable of detecting a plurality of specific substances.

In the SPR phenomenon measuring chip shown in FIG.
As shown by 1a, 11b, and 11c, light must be incident on each of them. However, a branch structure such as a Y-branch 17, an optical coupler 18, and a slab waveguide 19 as shown in FIGS. By forming the light in the waveguide, the incident light can be reduced to one. Also, if the waveguide has a switch function such as a thermo-optical switch, light can be incident on an arbitrary waveguide.

In the optical coupler 18 shown in FIG. 10, light coupling occurs at a portion near the core 9, and light incident on one of 11d and 11e is split into 12d and 12e and emitted. By arranging the metal thin film 16 after branching, measurement of the SPR resonance phenomenon at two places becomes possible. It is possible to make more branches by stacking the optical coupler and the Y-branch waveguide in multiple stages, but in the slab waveguide 19 shown in FIG. 11, two or more branches can be made at once. , SPR in more locations (multiple channels)
It is suitable for measuring resonance phenomena.

FIG. 12 shows a multi-channel measurement method.
As shown in (1), an optical waveguide having a metal thin film 5 that causes the SPR phenomenon in a portion where the plurality of cores 9 face the side surface at an angle of, for example, 45 ° is considered. The angle to the side surface of the core is an angle at which light is totally reflected, and may be detected by a photoelectron detector as indicated by an arrow in FIG. 12, and it is sufficient that the core does not travel in the opposite direction.

The light incident on the core 11 propagates, causes an SPR phenomenon in the metal thin film 5, and converts the light reflected as shown by the arrow into a PSD (Position Sensitive D).
(detector: semiconductor optical position detector), line sensor 20, etc., the SPR phenomenon can be observed in multiple channels. In addition, if the waveguides of FIG. 12 are vertically overlapped, measurement can be performed with a greater number of channels, and observation in a plane region is possible.

As shown in FIG. 13, a method of forming a core for transmitting light reflected on the side surface is also conceivable.

Further, as shown in FIG. 14, the tip of the optical waveguide having two cores 9 is set at 45 ° so that light is reflected as shown by an arrow so that measurement can be performed in a finer area.
A shape in which the metal thin film 5 is formed on the surface thereof is also conceivable. The incident light 11 propagates through the core 9,
The light is reflected twice by the metal thin film 5 while causing the SPR phenomenon, and can be extracted as the emission light 12.

As a similar method, as shown in FIG.
The prism 21 is fixed to the tip of the optical waveguide having two cores, and the metal thin film 5 is formed on the surface. The incident light 11 propagates through the core 9, is reflected twice by the metal thin film on the prism 21 while causing the SPR phenomenon, and can be extracted as the outgoing light 12. One of the two reflections may be a mirror surface for causing perfect reflection.

The SPR phenomenon measuring chip having the shape as shown in FIG. 14 can be manufactured by the procedure shown in FIGS. 16A to 16E. An optical waveguide having a core 9 embedded in a clad 8 as shown in FIG. FIG. 16b shows an optical waveguide in which the tip is sharpened at an angle of 45 °.
Cut with 2. Then, as shown in FIG. 16c, two waveguides having a sharpened tip at 45 ° are formed. The two waveguides are bonded together as shown in FIG.
It can be manufactured by forming the metal thin film 5 on the sharpened surface as shown in FIG.

The optical waveguide shown in FIG. 14 has a core diameter of several μm.
In this case, it is possible to measure the SPR in a square of several μm, for example, by inserting the SPR phenomenon measuring chip at an arbitrary position in a sample.

As a measuring method using the SPR phenomenon measuring chip, if a monochromatic light source is used as the incident light, the amount of the outgoing light is detected by the photodetector and the change in the sample can be inferred from the change. If a wave number variable (wavelength variable) light source is used as the incident light, the outgoing light is measured by a photodetector,
A spectrum curve in which the horizontal axis in FIG. 24 is a wave number (wavelength) can be obtained. The same curve can be obtained by using a wide wavelength light source such as a white light source as the incident light and measuring the outgoing light with a spectroscope.

As for the connection between the SPR phenomenon measuring chip and the light source / photodetector, as shown in FIG. 17, a method of fixing the optical fiber 24 with a fixture 23 such as a splice or an array and bonding the optical fiber 24 to the optical waveguide portion can be considered. As an application of FIG. 17, there is also a method in which a groove for inserting and fixing an optical fiber is manufactured at the time of manufacturing an optical waveguide, and the fiber is fixed to the groove at an appropriate stage.

In any case, the conventional optical waveguide fabrication technology and optical waveguide-optical fiber connection technology for optical communication can be applied. Further, in this connection, the diameter of the core on the emission side is made smaller than the diameter of the core on the incidence side, so that the coupling can be simplified. The type shown in FIG. 17 can be easily connected to the light source / photodetector by the optical fiber connector 25.
The exchange of the phenomenon measurement chip is easy, and the selection of the light source and the light receiver can be freely changed. In addition, because the SPR phenomenon measurement chip is difficult to insert like a vacuum device or needs to be explosion-proof because the optical fiber with low loss is used,
It is also possible to install a plurality of devices at remote locations and perform measurements at hand.

In order to cause the SPR phenomenon effectively, it is necessary to input p-polarized light, and the following three methods can be considered. (1) A method in which the optical fiber 24 in FIG. 17 is used as a polarization maintaining fiber, (2) A method in which a groove is cut in a core in the middle of an optical waveguide, and a polarizing plate is fixed in the groove.
(3) There is a method of attaching a polarizing plate to the entrance end or the exit end of the optical waveguide of FIG. Further, if the optical waveguide fabrication technique is used, as shown in FIG.
6 can also be formed.

The shape of the overcladding 10 shown in FIG. 2D is made to allow the sample to flow, and the top plate 2 is placed thereon.
By attaching the capillary 8 and attaching a capillary 27 or the like which is a pipe for flowing a sample serving as a sample entrance / exit, a chip for measuring the SPR phenomenon and a flow cell can be integrated. Although the top plate 28 is shown in FIG. 18 as being transparent for easy understanding, it need not be transparent.

As the metal thin film causing the surface plasmon resonance phenomenon, a metal thin film conventionally used in this type of SPR phenomenon measuring apparatus can be effectively used. This metal thin film preferably has a thickness of 40 to 52 nm. If it is out of this range, it becomes difficult to detect the surface plasmon resonance phenomenon using reflected light, which causes a disadvantage.

[0057]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

[0058]

Embodiment 1 A polymer clad material is applied on a transparent glass wafer substrate having a diameter of 10 cm and a thickness of 1 mm by a spin coating method, and cured by heating to form a 400 μm clad layer. Next, using a dicing saw, the width 200 μm and the depth 200
A linear groove of μm is formed, and a polymer core material is poured into the groove, and is cured by heating.

Thereafter, the surface is polished to a smooth surface, and several tens of titanium are formed thereon by sputtering,
Further, gold is formed thereon by sputtering, and a metal thin film having a total thickness of 500 ° is formed. UV on metal thin film
A hardening type polymer clad material is applied, and a necessary part is hardened using a mask, thereby producing a simple cell for a sample.

Since there is a possibility that impurities may be present on the metal thin film as it is, the reactive ion etching method (R
active Ion Etching: RIE
It is better to perform dry etching lightly to remove impurities.

According to the above method, the SPR phenomenon in which the waveguide core as shown in FIG. 1 has a linear shape, a cross-sectional shape of 200 × 200 μm, a metal thin film on the core, and a cell for a sample. A measurement chip can be manufactured.

If a large number of such linear waveguide cores are manufactured on one chip, an SPR phenomenon measurement chip as shown in FIGS. 8 to 12, which can easily perform multi-channel measurement, can be manufactured.

The method of using an optical fiber for optically connecting the SPR phenomenon measuring chip is as follows.
Cut a V-shaped groove in the glass block, and put a clad diameter 25 in the groove.
An optical fiber having a diameter of 0 μm and a core diameter of 200 μm is embedded, sandwiched between the glass fibers from above, and fixed with a UV adhesive. The surface of the glass block to which the optical fiber is fixed is connected to the SPR phenomenon measuring chip by optical polishing, and the SPR phenomenon measuring chip side is also optically polished. The glass block to which the optical fiber is fixed and the SPR phenomenon measurement chip can be easily connected using a connection device for connecting the optical communication waveguide to the optical fiber array.

Also in the SPR phenomenon measuring chip having a large number of cores as shown in FIG. 8, a plurality of V-shaped grooves are formed, and the pitch between the grooves is made the same as the pitch between the cores of the waveguide. It can be easily connected using the device.

If connectors are formed on the optical fibers connected to the light input side and the light output side, connection to the light source and the spectroscope becomes very easy, and measurement is performed while changing the type of the light source and the spectrometer. It is also possible.

[0066]

EXAMPLE 2 A 40 μm-thick cladding material having a refractive index of 1.5185 (wavelength: 633 nm) of the epoxy-based oligomer material of the structural formula 2 was applied on a transparent glass wafer substrate having a diameter of 10 cm and a thickness of 1 mm. . After ultraviolet light exposure and curing, the same epoxy-based material has a refractive index of 1.5394
(Wavelength 633 nm) of a waveguide core material, width 62.
UV irradiation through a 5 μm U-shaped pattern mask, dissolving and removing portions other than those exposed and cured by post-exposure development,
A letter-shaped core was formed. The same material as the pre-cladding material was applied thereon at 40 μm and allowed to stand, and then irradiated with ultraviolet light through a pattern mask exposing a part of the core to dissolve and remove cured and uncured portions.

By the above method, an SPR phenomenon measuring chip having a U-shaped waveguide core, a cross-sectional shape of 10 × 10 μm, and a metal thin film on the core as shown in FIG. Is possible.

After forming the U-shaped core, a cladding layer is formed to a thickness of 50 μm. Thereafter, the side surface of the U-shaped core is cut with a dicing saw and a metal thin film is formed in direct contact with the side surface of the core, so that the waveguide core as shown in FIG. An SPR phenomenon measurement chip having a size of 50 × 50 μm and having a metal thin film on the side surface of the core can be manufactured.

These SPs having a U-shaped waveguide core
The R phenomenon measuring chip has an advantage that the connection with the optical fiber only needs to be made once. Two V-shaped grooves are formed in the glass block, an optical fiber is embedded in the grooves, sandwiched between glass plates, and fixed with a UV adhesive. At this time, the width of the two grooves is
The distance between the entrance side and the exit side of the U-shaped optical fiber is set to be the same. The glass block to which the two optical fibers are fixed is connected to the SPR phenomenon measurement chip by the connection device described above.

[0070]

Embodiment 3 Chromium is sputtered on a silicon substrate to a thickness of about 1 μm, a polymer cladding material is applied by spin coating, and heated to form a cladding layer of 50 μm. Thereafter, a solution prepared by adjusting a liquid epoxy oligomer having the following structural formula and a photopolymerization initiator of 2 wt% was prepared as a UV photosensitive core material.

[0071]

Embedded image

A UV-sensitive core material is similarly applied by a spin coating method, and is irradiated with UV light through a patterned mask so as to form a core having a desired shape, followed by curing. The height of the core is 10 μm. The uncured part is removed with a solvent, and then the polymer clad material is placed 50 μm above the core.
Apply, heat and cure to a thickness of

Then, the shape of the teeth of the dicing saw is 45
°, and cut to the silicon substrate in the direction perpendicular to the waveguide core. After cutting, the entire substrate is immersed in a chromium dissolving solution to dissolve the chromium, and the polymer waveguide portion is peeled off from the silicon substrate. Then, the tip is 45 °
The two cut waveguides are formed, and the two are bonded together, and a metal thin film is sputtered on the cut surface.

By the above method, it is possible to manufacture an SPR phenomenon measurement chip having two waveguides as shown in FIG. 13, having a sharpened tip at 45 ° and forming a metal thin film.

[0075]

Embodiment 4 A polymer clad material was applied on a glass substrate by spin coating, and heated to form a clad layer having a thickness of 50 μm.
m. Thereafter, as a UV photosensitive core material, imide polygoma represented by the following structural formula and photopolymerization initiator 2
A solution in which wt% was adjusted was prepared.

[0076]

Embedded image

A UV-sensitive core material is similarly applied by a spin coating method, and is irradiated with UV light through a mask provided with a pattern so as to form a core having a desired shape, and is cured. The height of the core is 10 μm. The uncured part is removed with a solvent, and then the polymer clad material is placed 50 μm above the core.
Apply, heat and cure to a thickness of Next, using a dicing saw, cut at an angle of 45 ° with the core,
The cut surface is optically polished to form a metal thin film.

Since the light incident on the metal thin film at an incident angle of 45 degrees is reflected and propagates through the clad, it is necessary to place a photodetector at the point where the light is reflected. By manufacturing, reflected light can be extracted with an optical fiber.

By the above-described method, it is possible to manufacture an SPR phenomenon measuring chip of a type for measuring the light reflected by the metal thin film on the end face of the waveguide cut at an angle of 45 °.

By arranging a large number of waveguide cores of this type side by side, a multi-channel SPR phenomenon measuring chip as shown in FIG. 8 can be manufactured. It is.

[0081]

Example 5 After a metal thin film was formed in the same manner as in Example 1, a solution prepared by adjusting an acrylic oligomer represented by the following structural formula to a photopolymerization initiator of 2 wt% was prepared as a UV-sensitive cladding material. .

[0082]

Embedded image

A UV-curable polymer clad is applied by spin coating, and UV is irradiated using a mask having a pattern capable of forming a flow path. Of course, the flow path is SPR
It overlaps the phenomenon measurement area. After removing the uncured portion with a solvent, capillaries are attached to the inlet and outlet of the flow channel and fixed with a UV adhesive. Thereafter, the entire chip is covered with a top plate.

By the above-described method, it is possible to manufacture an SPR phenomenon measuring chip in which a flow cell as shown in FIG. 18 is integrated.

[0085]

Embodiment 6 Cr is formed by about 1 μm on a glass substrate by a sputtering method, and a UV-curable polymer material serving as a core is applied thereon so as to have a thickness of 62.5 μm, and UV light is applied through a mask. Irradiate and cure only the core.

The uncured portion is removed with an organic solvent, and a polymer material serving as a clad is applied thereon and cured. A glass substrate is stuck thereon, immersed in a solvent that dissolves Cr, and the first glass substrate is peeled off.

The peeled surface is a smooth surface and does not require a special method such as polishing. U on the peeled surface
Apply V-curable overcladding, harden except for the measurement surface, and apply Ti on it to increase the adhesion to 50 °
Au is formed at 450 ° by a sputtering method.

FIG. 19 is a schematic diagram of the manufactured optical waveguide type SPR phenomenon measuring chip. In the figure, (a) is a plan view,
(B) is a side view, and (c) is an AA cross-sectional view of FIG. Four optical waveguide cores 9 were fabricated on one SPR phenomenon measurement chip, and the cores had a cross-sectional shape of 62.5 × 62.5 μm.
m and a linear shape. An optical fiber 30 having a core of 62.5 μm and an outer diameter of 125 μm was used for inputting and outputting light to the SPR phenomenon measurement chip. The overcladding 10 is not formed in the shaded portion in the figure, and in that portion, the core 9 of the optical waveguide and the metal thin film 5 are in direct contact, and are arranged to cause the SPR phenomenon.

The optical fiber was connected to a halogen lamp and a spectroscope, and the results of actual measurement are shown in FIGS.

FIG. 20 shows a spectrum when there is no sample (air is used as a sample) and a spectrum when water is dropped on the measurement area. By dropping water, S
It can be seen that the PR phenomenon has occurred and the transmittance has decreased.
FIG. 21 shows that the sample was made of water (shown by a), 1 wt% KC
The measurement was performed as 1 (shown by b) and a 10 wt% KCl solution (shown by c). From the difference in the refractive index of each solution, it can be seen that a change has appeared in the spectrum, indicating that the solution exhibits sufficient performance for measuring the SPR phenomenon.

[0091]

Example 7 An optical waveguide type SPR phenomenon was performed in the same manner as in Example 8 by using a solution prepared by adjusting an acrylic oligomer represented by the following structural formula and 2 wt% of a photopolymerization initiator as a UV-curable polymer material. A measurement chip was prepared.

[0092]

Embedded image

[0093]

As described above, according to the present invention,
Since it is manufactured using optical waveguide fabrication technology with high versatility and productivity, it has various functions such as a sensor that is compact, easy to replace, and can simultaneously measure at multiple locations, and a multi-channel sensor that can detect multiple samples. Can be easily provided. Further, according to the method of manufacturing the optical waveguide type SPR phenomenon measuring chip, various functions can be provided, such as manufacturing a large number of optical waveguide cores on one chip or branching in the middle. It is possible to produce a large number of phenomenon measuring chips at low cost.

[Brief description of the drawings]

FIG. 1 is a perspective view of one embodiment of an optical waveguide type SPR phenomenon measuring chip according to the present invention.

FIG. 2 is an explanatory view of a method of manufacturing an optical waveguide type SPR phenomenon measuring chip.

FIG. 3 is an explanatory view of a method of manufacturing an optical waveguide type SPR phenomenon measuring chip.

FIG. 4 is an explanatory view of a method for manufacturing an optical waveguide type SPR phenomenon measuring chip.

FIG. 5 is a schematic view of an optical waveguide type SPR phenomenon measuring chip having a linear core shape.

FIG. 6 is a schematic view of an optical waveguide type SPR phenomenon measuring chip having a U-shaped core.

FIG. 7 shows an optical waveguide type S having a U-shaped core (side surface measurement surface).
Schematic diagram of a PR phenomenon measurement chip.

FIG. 8 is a schematic diagram of an optical waveguide type SPR phenomenon measurement chip having a plurality of cores.

FIG. 9 is a schematic diagram of an optical waveguide type SPR phenomenon measuring chip having a Y-branch.

FIG. 10 is a schematic view of an optical waveguide type SPR phenomenon measuring chip having an optical coupler.

FIG. 11 is a schematic view of an optical waveguide type SPR phenomenon measuring chip having a slab waveguide.

FIG. 12 is a schematic diagram of a multi-channel optical waveguide type SPR phenomenon measuring chip.

FIG. 13 is a schematic diagram of a side reflection type optical waveguide type SPR phenomenon measuring chip.

FIG. 14 is a schematic view of an optical waveguide type SPR measurement phenomenon chip having a tip of the optical waveguide as a measurement surface.

FIG. 15 shows an optical waveguide type S in which an optical waveguide and a prism are combined.
Schematic diagram of a PR measurement phenomenon chip.

FIG. 16a is an explanatory view of the method for manufacturing the optical waveguide measurement chip of FIG.

16b is an explanatory diagram of the method for manufacturing the optical waveguide measurement chip in FIG.

16c is an explanatory diagram of the method for manufacturing the optical waveguide measurement chip in FIG.

16D is an explanatory diagram of the method for manufacturing the optical waveguide measurement chip in FIG.

FIG. 16e is an explanatory view of the method for manufacturing the optical waveguide measurement chip of FIG.

FIG. 17 is a perspective view of an optical waveguide type SPR phenomenon measuring chip connected to an optical fiber by an optical fiber splice and an optical fiber array.

FIG. 18 shows an optical waveguide type SP having a flow path formed on a metal thin film.
The perspective view of an R phenomenon measurement chip.

FIG. 19 is a schematic view of an optical waveguide type SPR phenomenon measuring chip manufactured according to an eighth embodiment.

FIG. 20 is a view showing a measurement result according to Example 8.

FIG. 21 is a view showing a measurement result according to Example 8.

FIG. 22 is a schematic diagram of a conventional SPR phenomenon measurement device in an incident angle measurement type.

FIG. 23 shows an SPR in a conventional spectrum measurement type.
The schematic diagram of a phenomenon measuring device.

FIG. 24 is a view showing a result of measuring an SPR phenomenon using the apparatus configured in FIG. 22;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source 2 Polarizer (polarizer) 3 Lens 4 High refractive index prism 5 Metal thin film 6 Sample (measured object) 7 Photoelectron detector 8 Cladding 9 Waveguide core 10 Overcladding 11 Incident light 12 Outgoing light 13 Groove 14 Optical plane Substrate having chromium 15 Chromium film of about 1 μm (sacrifice layer) 16 Metal thin film written transparently 17 Y branch 18 Coupler 19 Slab waveguide 20 PSD 21 Prism 22 Blade 23 Optical fiber splice (optical fiber array) 24 Optical fiber 25 Optical fiber Connector 26 Flow path arranged on measurement surface 27 Capillary (piping for flowing sample) 28 Top plate

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Gen Iwasaki 2-3-1 Otemachi, Chiyoda-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (72) Inventor Tsutomu Horiuchi 2-3-3 Otemachi, Chiyoda-ku, Tokyo 1 Nippon Telegraph and Telephone Corporation (72) Inventor Tatsuya Tobita NTT Advanced Technology Co., Ltd. 2-1-1 Nishi Shinjuku, Shinjuku-ku, Tokyo (72) Inventor Hisao Tabei Tokyo (1-1) Nishi Shinjuku 2-chome, Shinjuku-ku, NTT Advanced Technology Co., Ltd. (72) Inventor Saburo Imamura 2-1-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo F-term in technology company (reference) 2G059 AA05 EE02 EE05 EE12 GG00 JJ12 JJ17 JJ19 JJ22 KK01 KK04 2H047 KA03 KA12 KA15 KB04 LA12 NA01 QA05 RA01

Claims (24)

[Claims] An optical waveguide having a core and a cladding provided around the core, the core having a higher refractive index than the cladding, and confining and propagating light incident on the core; An SPR phenomenon measuring chip having a metal thin film that at least partially contacts the surface and causes a surface plasmon resonance phenomenon, wherein the surface plasmon resonance phenomenon is measured by measuring light propagating through the core. An optical waveguide type SPR phenomenon measurement chip, wherein a sample to be measured is provided so as to contact the metal thin film. 2. The optical waveguide type SPR phenomenon according to claim 1, wherein the optical waveguide has a plurality of cores, and each of the cores is provided with a metal thin film so that at least a part thereof is in contact with each of the cores. Measurement chip. 3. The core of the optical waveguide has a branch structure,
2. The optical waveguide type SPR phenomenon measurement according to claim 1, wherein the output side has a plurality of cores by the branch structure, and a metal thin film is formed so that at least a part thereof comes into contact with the branch core. 3. Chips. 4. The optical waveguide type SPR phenomenon measuring chip according to claim 3, wherein the branching structure is any one or a combination of a Y branch, an optical coupler, and a slab waveguide. 5. The optical waveguide type SPR phenomenon measuring chip according to claim 3, wherein the branch structure has a switching function. 6. A metal thin film which causes a surface plasmon resonance phenomenon having a function of reflecting light incident on one end face of a core of an optical waveguide in a reverse direction, or a function of reflecting incident light in a reverse direction. The optical waveguide type SPR phenomenon measurement chip according to claim 1, further comprising a metal thin film that causes a surface plasmon resonance phenomenon on the core up to the end face having the following. 7. The optical waveguide, wherein the optical waveguide is connected to a light-entering core, the light-entering core, which is directed at a certain incident angle to the metal thin film formed perpendicularly to the optical waveguide, and The optical waveguide type SPR phenomenon measuring chip according to claim 1, further comprising a core that propagates and emits light affected by the surface plasmon resonance phenomenon reflected by the thin film. 8. The optical waveguide has two cores arranged in parallel, a tip of the optical waveguide is sharpened at an inclined angle of 45 °, and a metal thin film is formed on the sharpened surface. 2. The method according to claim 1, wherein when light is incident on one of the cores, the light is reflected by the sharpened surface, and reflected light affected by the surface plasmon resonance phenomenon is emitted from the other core. The optical waveguide type SPR phenomenon measurement chip as described in the above. 9. The optical waveguide has two optical waveguide cores, a prism is fixed to a tip of the optical waveguide, a metal thin film is formed on the surface of the prism, and light is incident on one of the cores. 2. The optical waveguide type SPR phenomenon measuring chip according to claim 1, wherein reflected light affected by the surface plasmon resonance phenomenon is emitted from the other core. 10. The optical waveguide, wherein a groove is formed in a core portion upstream of the metal thin film in a light propagation direction, and a polarizing plate is incorporated in the groove, or a polarizing plate is provided on an incident end face or an output end face of the core. 2. The optical waveguide type SPR phenomenon measuring chip according to claim 1, wherein the optical waveguide type SPR phenomenon measuring chip can be measured by attaching it. 11. The optical waveguide according to claim 1, wherein the optical waveguide has a core on a light incident side and a core on a light emitting side for emitting light, and a cross-sectional dimension of the core on the light incident side is larger. 2. The optical waveguide type SPR phenomenon measuring chip according to 1. 12. The optical waveguide type SPR phenomenon measuring chip according to claim 1, wherein a channel is formed so that the sample flows on the metal thin film. 13. A step of forming a groove having a desired shape for forming a core on a transparent clad substrate, a step of forming a core having a higher refractive index than the clad material substrate in the groove.
On the formed core, a metal thin film causing a surface plasmon resonance phenomenon is formed, and in a portion excluding the metal thin film portion,
A method for manufacturing an optical waveguide type SPR phenomenon measuring chip, comprising a step of forming an over cladding having a lower refractive index than the core. 14. A step of forming a core having a desired shape and a refractive index higher than that of the clad on a transparent clad substrate, a step of forming the clad so as to have the same height as the core, Forming a metal thin film causing a surface plasmon resonance phenomenon thereon, and forming an over cladding having a lower refractive index than the core in a portion excluding the metal thin film portion. Manufacturing method of measuring chip. 15. A step of forming a readily dissolvable metal sacrificial layer on a substrate having an optical plane, a step of forming a core having a desired shape and a refractive index higher than that of a clad on the sacrificial metal layer, A step of forming a clad thicker than the core on the core, a step of dipping in a solution for dissolving the sacrificial layer, dissolving the sacrificial layer, and removing a substrate having an optical plane, the core being exposed Forming a metal thin film causing a surface plasmon resonance phenomenon on a surface, and forming an over cladding having a lower refractive index than a core in a portion excluding the metal thin film portion. Method for manufacturing type SPR phenomenon measurement chip. 16. After forming a core or cladding,
The optical waveguide type SPR phenomenon measuring chip according to any one of claims 13 to 15, wherein a core or a clad having a desired shape is produced by cutting. 17. After forming a core or cladding,
By applying resist, curing the resist by irradiating light through a mask or directly and directly to selected parts, removing the uncured part with a solvent, and then removing the core or clad of the part without resist by etching The method of manufacturing an optical waveguide type SPR phenomenon measuring chip according to any one of claims 13 to 15, wherein a core or a clad having a desired shape is manufactured. 18. A material for forming a core and a clad is a transparent photosensitive material, and after applying the material on a substrate,
A latent image pattern is formed by irradiating light to a selected portion directly or through a mask, and after repeating the above operations as necessary, a non-irradiated portion is removed with a solvent to form a core or clad having a desired shape. The method for manufacturing an optical waveguide type SPR phenomenon measuring chip according to any one of claims 13 to 15, wherein: 19. The optical waveguide according to claim 18, wherein the transparent photosensitive substance is a photosensitive polyimide, epoxy, acrylic, or silicone oligomer or monomer. Method for manufacturing type SPR phenomenon measurement chip. 20. The transparent photosensitive substance has a chemical structural formula: Wherein R ₁ is a bisalkyl- or bisperfluoroalkyl-benzene, R ₂ is an alkyl, alkylphenylene, perfluorophenylene group, and R ₃ is an alkyl group or a fluoroalkyl group. 20. The method according to claim 19, wherein the chip is an oligomer or a monomer. 21. The transparent photosensitive substance has a chemical structural formula: (Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkyl group, an alkoxy group, or a trifluoromethyl group; X ₁ , X ₂ , and X ₃ represent a linking group; Group or Is shown. 20. The method for manufacturing an optical waveguide type SPR phenomenon measuring chip according to claim 19, wherein the optical waveguide type SPR phenomenon measuring chip is an epoxy oligomer or a monomer represented by the following formula: 22. The transparent photosensitive substance has a chemical structural formula: (Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an alkyl group, an alkoxy group, or a trifluoromethyl group, X ₁ , X ₂ , and X ₃ represent a linking group, and Y represents an acrylic 20. The method of manufacturing an optical waveguide type SPR phenomenon measuring chip according to claim 19, wherein the optical waveguide type SPR phenomenon measuring chip is an acrylic oligomer or a monomer represented by the following formula: 23. The transparent photosensitive substance has a chemical structural formula: (In the formula, X represents a hydrogen atom, a deuterium atom, a halogen atom, an alkyl group, or an alkoxy group, m represents an integer of 1 to 4. x and y show the abundance ratio of each unit. R ₁ and R ₂ represent a methyl group, an ethyl group, or an isopropyl group, and R ₁ and R ₂ may be the same.) 20. The optical waveguide type SP according to claim 19,
Manufacturing method of R phenomenon measurement chip. 24. An optical waveguide comprising: a core; and a cladding provided around the core, wherein the core has a higher refractive index than the cladding and is configured to confine and propagate light incident on the core. A sample is provided so as to be in contact with the metal thin film of the optical waveguide type SPR phenomenon measurement chip including a waveguide and a metal thin film that causes a surface plasmon resonance phenomenon that at least partially contacts the core, and light is emitted from the core. S is characterized by measuring surface plasmon resonance phenomena affected by the refractive index of a sample in contact with the metal thin film by measuring light that has entered and propagated through the core.
PR phenomenon measurement method.