JP2009103518A - Method for manufacturing functional film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a functional film, which can form the film having a desired thickness and a desired planar dimension. <P>SOLUTION: The method includes: a first step of applying a functional film agent 4 which contains a solvent for dissolving or swelling a functional substance and a polymer matrix layer 2, to the polymer matrix layer 2 disposed on a substrate 1; a second step of making the functional substance dispersed in the polymer matrix layer 2 by bringing the functional film agent 4 to diffuse into the polymer matrix layer 2; and a third step of forming the functional film 7 by solidifying the polymer matrix layer 2 in which the functional substance is made dispersed in the second step. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for producing a functional membrane, and in particular, a solid membrane sensor such as an ion sensor or a biosensor, a field effect transistor sensor, a crystal resonator, a functional membrane for a biofuel cell, a metal thin film, or a semiconductor thin film The present invention relates to a method for producing a functional film suitable for the manufacturing technique.

  Functions of ion-sensitive field effect transistor [Ion Selective Field Effect Transistor (abbreviation: ISFET)], ion-selective electrode [Ion Selective Electrode (abbreviation: ISE)], or crystal unit [Quartz Crystal Microbalance (abbreviation: QCM)] The functional film (sensitive film) is usually formed using a functional film agent composed of a polymer, a functional material (sensitive material), a material such as a plasticizer, and an organic solvent. As a film forming method, an ink-jet method (Non-Patent Document 1), a dip coating method (Non-Patent Document 2), a spin coating method, a spray coating method, or a casting method is known.

On the other hand, with regard to the ISFET functional film fabrication method, an inorganic oxide such as silicon oxide is formed on the ISFET silicon substrate by dry oxidation, and an organic silane monomolecular film is formed by exposing it to an organic solution or vapor. And a method for producing an ion sensitive film for ISFET (Patent Document 2) in which an ion sensitive film is formed by vapor deposition polymerization of an ionophore compound having a functional group capable of vapor deposition polymerization. Yes. As for the functional film manufacturing method of the crystal resonator, a silicon oxide film is formed on the surface of the transducer mass detection transducer, and a silicon-containing organic thin film generated from a silane coupling agent is formed on the silicon oxide film. A method of using this film as a novel sensor probe (Patent Document 3) has been proposed.
Hitoshi Yagi and Tadashi Sakai, Sensors and Actuators B, 13-14 (1993) 212. Helen James, Gary Carmack, and Henry Freiser, Analytical Chemistry, 44, (1972) 856. JP 2004-117073 A JP-A-6-273376 JP 2000-131122 A

  However, since the functional film agent used in the above-described film forming method has a high viscosity in which a polymer matrix serving as a support for the functional film is previously dispersed in an organic solvent, Is difficult. In addition, when the film is formed using the ink jet method, the solvent evaporates, so that the viscosity of the film agent is changed to cause nozzle clogging. In recent years, a technology for rapidly forming a functional film in a minute region of a substrate has become more and more important due to the demand for small disposable sensors and bio-embedded sensors. However, in the conventional method, it is difficult to reduce the droplet size of the film agent, and thus it is difficult to form a film on a minute region. In addition, since film formation is performed by diffusing droplets of a film agent, it is difficult to form a functional film having a desired film thickness and a desired film area with a uniform film thickness.

  In addition, the functional film (sensitive film) created on the gate electrode of ISFET, the solid electrode of ISE, or the surface of the transducer-type detection transducer using the conventional film formation method is not only easy to peel off, but also the sensitive film The adhesion between the gate electrode of ISFET and the solid electrode of ISE is also poor. Therefore, degradation of sensor sensitivity, selectivity, durability, etc. caused by the penetration of the liquid to be measured from between the sensitive membrane and the gate electrode of ISFET or between the sensitive membrane and the solid electrode of ISE is a major issue. Yes.

  In any of the above-described conventional techniques, the manufacturing process is complicated and the manufacturing conditions are not mild. In addition, functional films that can be produced are limited to substances suitable for the respective production methods, and various types of functional films cannot be produced.

  Therefore, in view of the above problems, the present invention can quickly and easily produce a functional film that is difficult to peel off from a substrate in a minute region of the substrate, and a functional film having a desired film thickness and a desired film area. It aims at providing the manufacturing method of the functional film | membrane which can form into a film.

  In order to solve such problems, according to one aspect of the present invention, a functional film containing a functional substance and a solvent that dissolves or expands the polymer matrix layer in a polymer matrix layer disposed on a substrate. A first step of supplying an agent, a second step of dispersing the functional material in the polymer matrix layer by diffusing the functional film agent into the polymer matrix layer, and in the second step And a third step of forming the functional film by solidifying the polymer matrix layer in which the functional substance is dispersed.

  According to the method for producing a functional film of the present invention, a functional film having a desired film shape, film thickness, and film area can be quickly and easily produced at a desired position such as a micro region of a substrate. . Further, the type of functional film that can be produced is not limited.

  Hereinafter, a method for producing a functional film according to an embodiment of the present invention will be described with reference to FIGS. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals, and redundant description is omitted. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Accordingly, specific dimensions and the like should be determined with reference to the following description. Also, the drawings include portions having different dimensional relationships and ratios.

<Basic structure of functional membrane production equipment>
The functional film manufacturing method according to the embodiment of the present invention is performed using a functional film manufacturing apparatus. FIG. 1 is a flowchart for explaining a method of manufacturing a functional film according to this embodiment. As shown in FIG. 1, the functional film manufacturing apparatus functions in a space inside a template 3 provided on a substrate 1 so as to surround a polymer matrix layer 2 formed on the substrate 1. A functional part is dispersed in the polymer matrix layer 2 by diffusing the functional film agent 4 with a supply part (functional film agent supply part) 5 for supplying the functional film agent 4 containing the functional substance and the solvent. Diffusion unit 6, immobilization unit 8 for solidifying polymer matrix layer 2 to form functional film 7, and firing functional film 7 to remove polymer matrix layer 2 and solvents such as organic substances. And a sintered part 10 for producing a functional film 9 formed by sintering the functional film 7. The functional film 7 or the functional film 9 after sintering is manufactured using this functional film manufacturing apparatus.

  The polymer matrix layer 2 is a polymer thin film, a polymer fiber or porous thin film, or a polymer gel thin film. The diffusion unit 6 naturally diffuses or forcibly diffuses the functional film agent 4 using a physical method such as vibration. The immobilization unit 8 hardens the polymer matrix layer 2 by changing external conditions such as temperature and evaporating the solvent in which the polymer matrix layer 2 is dissolved or swollen. When the polymer matrix layer 2 is a polymer gel thin film, the immobilization unit 8 hardens the polymer matrix layer 2 by changing the external conditions to gel the polymer matrix layer 2.

  For the polymer matrix layer 2 shown in FIG. 1, a thin film, fibrous or porous polymer matrix or polymer gel is used. The polymer matrix may be a polymer matrix mainly composed of metal fibers or metal mesh coated with a polymer thin film, if necessary.

  As the polymer material, any of a water-soluble polymer material and a water-insoluble polymer material can be used. When water is used as the solvent for the functional film agent 4, it is desirable to use a water-soluble polymer material. On the other hand, when an organic solvent is used as the solvent for the functional film agent 4, it is desirable to use a water-insoluble polymer material, in other words, a polymer material that is readily soluble in the organic solvent.

  As the water-soluble polymer material, for example, polyvinylpyrrolidone (PVP), polyethyleneimine (PEI), polyacrylic acid (PAA), polyvinyl alcohol (PVA), a polyacrylic acid polymer, or the like can be used. As the water-insoluble polymer material, for example, polyvinyl chloride, polyurethane, silicone rubber, polyacrylamide, cellulose acetate, cellulose, polystyrene and the like can be used. The water-soluble polymer material or the water-insoluble polymer material can be appropriately selected according to the type or use of the solvent used in the functional film agent 4, and is thus limited to these listed substances. Is not to be done.

  Moreover, as a polymer gel, the gel which causes a swelling or shrinkage | contraction or a phase transition according to the change of temperature, light, a solvent composition, and an electromagnetic field can be used, for example. As the polymer gel, for example, a sodium polyacrylate gel can be used. Further, for example, as a gel that causes a phase transition depending on temperature, for example, a polymer gel having a phase transition temperature of 20 ° C., Meviol Gel (registered trademark) [Mebiolgel, sold by Ikeda Chemical Co., Ltd.] can be used. .

  As the substrate 1, a glass substrate, a metal substrate, a ceramic substrate, a polymer substrate, or the like can be used. On the other hand, to solid film type sensors (chemical sensors, biosensors, immunosensors), field effect transistor type sensors (chemically sensitive FET (abbreviated CHEMFET) and FET biosensors), or crystal resonators When considering the application of the functional film, a solid electrode of a solid film type sensor, a gate electrode of a field effect transistor, and a vibrator type detection transducer of a crystal oscillator can be used as the substrate 1, respectively. In other words, the polymer matrix layer 2 may be provided on the substrate 1, and the type of the substrate is not particularly limited.

  Further, the same material as the polymer matrix layer 2 can be used as the material of the substrate 1. In this case, by appropriately controlling the supply amount of the functional film agent 4 supplied from the supply unit 5 and external conditions such as temperature and vibration in the diffusion unit 6, the functional film agent 4 is applied to the substrate 1. Can be appropriately controlled.

  As a functional substance, a substance capable of sensing an ion for detection or a substance for detection, for example, an ion-sensitive substance, an enzyme, a protein, a nucleic acid, a nucleic acid-related substance, a peptide, a polypeptide, a crown ether, an ion channel, a molecular tongue, a cyclone Dextrin or metal fine particles modified with various sensitive substances can be used. For the purpose of producing a metal thin film, metal nanoparticles or metal fine particles are used as a functional substance. For the purpose of manufacturing a semiconductor thin film, semiconductor nanoparticles or semiconductor fine particles can be used as a functional substance.

  The functional film agent 4 contains a functional substance, and also includes a liquid that can swell, phase transition, or dissolve the polymer matrix layer 2. When the polymer matrix layer 2 is a polymer gel, it is desirable to use a liquid having the ability to permeate and diffuse into the polymer gel. On the other hand, when the polymer matrix layer 2 is not a polymer gel, it is desirable to use a liquid having the ability to dissolve the polymer matrix layer 2.

  In addition to containing a functional substance and a liquid, a functional film agent 4 containing a substance such as a plasticizer that softens the polymer matrix layer 2 can be used. Moreover, when the produced functional film 7 is used as a sensitive film of a sensor, the functional film agent 4 containing a substance such as an ion exclusion agent can be used depending on the type of ions to be detected.

  As the liquid contained in the functional film agent 4, water, a nonaqueous solvent, or a mixed solvent can be used. As the non-aqueous solvent, for example, pure solvent tetrahydrofuran (THF), acetic acid, butyl acetate, ethyl acetate, toluene, acetonitrile, methanol, 2-acetoxy-1-methoxypropane and the like can be used. Moreover, two or more types of these pure solvents can be mixed and used as a mixed solvent. In addition, as the liquid, for example, a liquid ionic liquid composed of a combination of an aromatic cation containing nitrogen such as imidazolium or pyridinium and various inorganic anions can be used.

  The supply unit 5 preferably includes a device that supplies a certain amount of the functional film agent 4 to the polymer matrix layer 2. For example, an inkjet mechanism, a coating mechanism, a printing mechanism, or the like can be used as appropriate. Since the functional film agent 4 used in the method for producing a functional film according to the present embodiment does not include a polymer matrix serving as a carrier for the functional film 7, the viscosity of the functional film agent 4 is low. Therefore, when producing the functional film 7 in a minute region, an apparatus such as an automatic microinjection device, an ultra-trace dispenser, a micro dispenser, and a femtoliter (fL) pump is applied to the supply unit 5. In addition, the supply device of the functional film agent 4 can be appropriately selected according to the area of the functional film 7 and the type of the functional film agent 4.

  The diffusion unit 6 is a device 11 that can appropriately control the temperature of the polymer matrix layer 2, for example, a device that can heat the polymer matrix layer 2 with a laser, or a device that can heat the polymer matrix layer 2 such as a thermostatic bath. It is preferable to provide. Alternatively, instead of this heatable device, the diffusion unit 6 includes a device 11 that shakes the polymer matrix layer 2 after the functional film agent 4 is added, such as a shaker (shaker) or an ultrasonic vibration device. Is desirable. Alternatively, in place of a heatable device or shaker, the diffusion unit 6 preferably includes a device 11 that generates an electric field that can efficiently move the metal fine particles contained in the functional film agent 4 to the polymer matrix. .

  The immobilization unit 8 can include a device 12 that can appropriately control the phase transition temperature of the polymer gel or a device 12 that efficiently evaporates a solvent that dissolves the polymer. In this case, a thermostat used in the diffusion unit 6 is used. Furthermore, the immobilization unit 8 can appropriately use a decompression device or a vacuum drying device according to the type of the functional film 7.

  The sintered part 10 may appropriately include a device 13 that can remove organic substances contained in the polymer matrix and the functional film agent 4 by sintering.

  In summary, when the apparatus for producing the functional film 9 is used, a functional thin film in which the area and film thickness of the film are controlled can be quickly and easily manufactured in a desired minute region.

<Method for producing functional film>
As shown in FIG. 1, the method for producing a functional film according to this embodiment includes a polymer matrix layer 2 such as a polymer thin film, a polymer nonwoven fabric, or a porous film surrounded by a template 3 on a substrate 1. Step 1 of adding a functional film agent 4 containing a functional substance to is performed. Next, the functional substance contained in the functional film agent 4 is uniformly dispersed in the polymer matrix by utilizing natural diffusion or forced diffusion of the functional film agent 4 (using a physical method such as vibration). Step 2 is performed. Subsequently, step 3 is performed in which the polymer matrix layer 2 is concentrated or dried by evaporating the solvent in which the polymer matrix layer 2 is dissolved due to changes in conditions such as temperature. In step 3, when the polymer matrix layer 2 is made of a polymer gel, a step of gelling the polymer matrix layer 2 is performed. By performing step 3, the functional film 7 is obtained. Furthermore, the functional film 7 is sintered to remove other organic substances such as the polymer matrix and the organic solvent, and the step 4 for obtaining the functional film 9 after sintering is performed.

  According to the above manufacturing method, a functional thin film having a desired film area and film thickness can be quickly and easily manufactured in a desired minute region.

  In the above step 1, the functional film agent 4 containing the functional substance is added to the template 3 using an injection device capable of controlling both the liquid amount and the flow rate of the functional film agent 4 in the polymer matrix layer 2. Can be added to the inner space. Moreover, the functional film agent 4 can be added also by methods, such as application | coating. In addition, when film-forming in a micro area | region, it is desirable to use the injection apparatus which can supply a very small amount of functional film agents 4.

  Step 2 aims to diffuse the functional film agent 4 into the polymer matrix layer 2. When the polymer matrix layer 2 that is easily soluble in the functional film agent 4 is used, the polymer matrix layer 2 is dissolved by supplying the functional film agent 4. When the functional substance naturally diffuses together with the functional film agent 4 into the polymer matrix to be dissolved, the functional substance is dispersed in the polymer matrix solution. In order to promote rapid diffusion or uniform diffusion of the functional substance, means for performing forced diffusion can be used. As the means for forced diffusion, for example, a control means capable of controlling the temperature of the functional film agent 4, the magnitude of vibration applied to the substrate 1, the frequency and level of sound waves and ultrasonic waves, or the strength of the magnetic field is used. Can do. Any of these forced diffusion means promotes the diffusion of the functional substance and has an effect of uniformly dispersing the functional substance in the polymer matrix layer 2.

  When the polymer matrix layer 2 is a polymer gel, the swelling or phase transition of the polymer gel is controlled by controlling conditions such as temperature, light, and electromagnetic field after the functional film agent 4 is supplied. be able to. In this case, the functional film agent 4 may be diffused into the swollen polymer gel or sol (polymer solution). When a polymer gel having a relatively low phase transition temperature is used, for example, Meviol Gel (registered trademark) has a phase transition temperature of 20 ° C., but this Meviol Gel (registered trademark) is liquid at 15 ° C. It is an aqueous solution (sol) and becomes a solid polymer gel at 25 ° C. or higher. Therefore, when the polymer matrix layer 2 is in the state of a polymer gel, the functional film agent 4 is added, and the temperature of the meviol gel (registered trademark) is appropriately controlled to cause phase transition of the polymer gel, In a solution (sol) state, the functional substance can be diffused or dispersed.

  Step 3 is a step of producing the functional film 7.

  When the polymer matrix layer 2 is easily soluble in the functional film agent 4, the polymer matrix layer 2 disperses the functional substance in the dissolved polymer matrix and then removes the solvent that dissolves the polymer matrix layer 2. I will let you. In this case, it is desirable to remove only the solvent that dissolves the polymer matrix layer 2, and it is desirable to leave useful substances such as a functional substance, a plasticizer, and an ion exclusion agent in the functional film 7. Therefore, as a solvent for dissolving the polymer matrix layer 2, it is usually desirable to use a volatile solvent or a solvent that can be easily removed at room temperature or 200 ° C. or lower. As a method for removing the solvent, a method of removing the solvent by allowing it to stand at room temperature or by drying it naturally can be used. Alternatively, the solvent may be removed by irradiating the solvent with laser light or performing heat treatment using a hot plate or a constant temperature dryer. The solvent can also be removed using a decompression device or a vacuum dryer. The method for removing the solvent may be appropriately selected depending on the functional film 7 and the type of the solvent.

  When the polymer matrix layer 2 serving as the carrier of the functional film 7 is a polymer gel, the solvent for swelling the polymer matrix layer 2 can be controlled by appropriately controlling external conditions (temperature, light, electromagnetic field, etc.). Both the film thickness and the degree of swelling of the functional film 7 can be appropriately controlled by appropriately increasing or decreasing the content. Alternatively, the functional film 7 can also be produced by returning the sol in which the functional substance is dispersed to a polymer gel.

  Step 4 is a step of producing a functional film 9 after sintering from the functional film 7. In step 4, the functional film 7 is basically sintered to remove the polymer matrix layer 2 and other organic substances, and the functional film 9 after sintering is produced. Therefore, when metal nanoparticles or metal fine particles that are not removed by sintering, or nanoparticles such as semiconductors or semiconductor fine particles are dispersed in the functional film 7, thin films such as metals or semiconductors are obtained by sintering. (Functional film 9) can be produced.

  Thus, according to the manufacturing method of the functional film concerning this embodiment, since the functional film agent 4 containing the functional substance etc. except a polymer is used, the functional film agent 4 with low viscosity is used. Can be handled easily. It becomes possible to easily form the functional film 7 or the functional film 9 after sintering in a minute region.

  Further, when the polymer thin film is used, the film thickness of the thin film and the area of the template 3 can be set to a desired size, so that the functional film 7 having a certain film thickness and area or the functional film after sintering. 9 can be formed. Furthermore, the functional film 7 that is difficult to peel off from the substrate 1 can be produced by appropriately selecting the material of the template 3 and appropriately selecting the thickness of the template 3 and the structure of the template 3.

  In other words, in the method for producing the functional film 7 or the functional film 9 after sintering, the functional film agent 4 that does not include a polymer matrix that serves as a support (carrier) for the functional substance is added to the substrate 1. Next, the functional film agent 4 is diffused into the polymer matrix layer 2 and further subjected to a drying or gelation step or a sintering step. For this reason, the functional film 7 having a certain film thickness and area and in which the functional substance is dispersed or the functional film 9 after sintering can be quickly and easily manufactured in a minute region. . That is, the film area and film thickness can be controlled.

<Application example 1 of manufacturing method of functional film>
Solid Film Sensor>
A functional film or a sensitive film used for a solid film type sensor, a field effect transistor type sensor, or a transducer of a crystal resonator can be manufactured by applying the functional film manufacturing method according to this embodiment. . In this case, the solid electrode, the gate electrode, or the vibrator-type detection transducer serves as a substrate, and a functional film or a sensitive film may be formed thereon.

  FIG. 2 shows an example of a method for producing a sensitive film of a solid film ion sensor. 2A is a cross-sectional view of a solid film ion sensor having a uniform film, and FIG. 2B is a top view of the solid film ion sensor having a mixed film. Here, FIG. 2 (a) is a cross-sectional view taken along the chain line ab in FIG. 2 (b) and seen in the direction of the arrow. The functional membrane shown in FIG. 2 (a) is a polymer matrix. Since the functional material is uniformly dispersed in the layer, there is no portion of the polymer matrix layer 18. On the other hand, in the case where a functional film is formed in the micropores by partial dissolution of the micropore edge portion of the polymer matrix layer, the polymer matrix layer 18 has a functional film 19 as shown in FIG. And the silver / silver halide layer 16 of the solid electrode. Here, FIG.2 (c) is the figure seen in the arrow direction in the cross section along chain line a'-b 'of FIG.2 (b). Since the residual layer of the polymer matrix layer 18 has a low plasticizer content, the adhesion to the solid electrode is excellent. On the other hand, the functional film adjacent to the remaining layer of the polymer matrix layer 18 has a high plasticizer content in the functional film, but the polymer material that is the support of the film is the same as the remaining layer, It is firmly adhered to this remaining layer. Therefore, the mixed film type functional film having such a structure is not easily peeled off from the solid electrode.

  The solid film ion sensor includes a template 14, a lead wire 15 provided under the template 14, a silver / silver halide layer 16 provided on the lead wire 15, these templates 14, An electrically insulating layer 17 formed in a space between the lead wire 15 and the silver / silver halide layer 16 and a polymer matrix layer 18 formed on the silver / silver halide layer 16 are provided. .

  In this solid film ion sensor, as shown in FIG. 2A, a solid electrode in which a silver / silver halide layer 16 is provided on a lead wire 15 is used instead of the substrate 1. The lead wire 15 and the silver / silver halide layer 16 are surrounded by the electrically insulating layer 17 and the template 14. The polymer matrix layer 18 is provided on the silver / silver halide layer 16 and the electrically insulating layer 17 and is further surrounded by the template 14. The method for producing a sensitive film requires three steps from Step 1 to Step 3 among the four steps for producing the functional film 7 shown in FIG. 1 or the functional film 9 after sintering. That is, the method for producing a sensitive film includes the step 1 of supplying a functional film agent 4 containing a functional substance (ion-sensitive substance) to the space between the template 14 and the polymer matrix layer 18, and the functional film agent. 4 is diffused into the polymer matrix layer 18 and a process 3 is removed to remove the solvent that dissolves the polymer matrix layer 18, and the sensitive film 19 is produced through these steps 1 to 3.

  When a solid film type sensor is manufactured, a polymer thin film, a porous polymer thin film, or a polymer nonwoven fabric can be used as the polymer matrix layer 18. When a polymer thin film is used, the sensitive film 19 as a functional film is formed by dissolving the polymer thin film. On the other hand, when a porous polymer thin film or a polymer nonwoven fabric is used, a uniform sensitive film 19 is formed by complete dissolution of the polymer. Alternatively, the micropores and voids in the polymer matrix layer 18 are partially dissolved to close the micropores and voids.

  As shown in FIGS. 2 (b) and 2 (c), the micropores are blocked by partially dissolving the edge portions of the micropores of the polymer matrix layer 18, so that the polymer matrix layer 18 and the sensitive membrane are sealed. 19 can also be formed. Usually, a functional film containing a large amount of a plasticizer has a problem that it has poor adhesion to a solid electrode serving as a substrate and is easily peeled off from the solid electrode. According to the method for producing a functional film according to Application Example 1, the polymer matrix layer 18 in the mixed film has a small plasticizer content, and the polymer matrix layer 18 has good adhesion to the substrate. The sensitive film 19 formed in the holes and voids can be held, and the sensitive film 19 can be brought into close contact with the solid electrode. Further, the polymer matrix layer 18 can be fixed under the template 14. When the polymer matrix structure as described above is used, the produced sensitive film 19 has a characteristic that it is difficult to peel off from the solid electrode.

  The polymer matrix layer 18 can be made of the same polymer as the template 14. In this case, it is desirable that the film thickness of the polymer matrix layer 18 be thinner than the height of the step of the template 14. When such a structure is used, the polymer matrix layer 18 having a smaller film thickness is almost dissolved by the functional film agent 4. On the other hand, in the template 14 having a step, a region having a depth substantially equal to the film thickness of the polymer matrix layer 18 is dissolved in the edge portion of the step, and the functional substance by diffusion of the functional film agent 4 into this region is dissolved. However, the effect is negligible because of the small amount.

  In consideration of characteristics such as sensitivity, selectivity, and durability of the sensor, it is desirable that the thickness of the produced sensitive film 19 is 1 μm to 500 μm. A more preferable film thickness is 5 μm to 300 μm. The most preferable film thickness is 10 μm to 150 μm. Since the film thickness is affected by the sensitivity, selectivity, and lifetime of the sensor, the film thickness is 10 μm to provide a low-cost, disposable, multi-channel ISE or ISFET with good sensitivity and high selectivity. It is desirable that the thickness be ˜150 μm.

  Usually, the plasticizer in the sensitive film 19 is used more than the polymer matrix serving as the carrier of the functional film in order to enhance the sensitivity and response characteristics of the sensitive film 19. The weight content of the plasticizer is about twice that of the polymer matrix. Therefore, since the produced sensitive film 19 contains a plasticizer, the film thickness of the sensitive film 19 is larger than the film thickness of the polymer matrix layer 18, so that the height of the template 14 is set to the produced sensitive film 19. May be provided in consideration of the height.

  Using the same functional membrane manufacturing method as in the example of FIG. 2, a multi-channel solid membrane ion sensor in which a plurality of solid membrane ion sensors of FIG. it can. FIG. 3 is a cross-sectional view of a multi-channel solid film ion sensor. In FIG. 3, a plurality of solid film ion sensors are formed as viewed in the direction of the arrow in the cross section along the chain line ab of the solid film ion sensor of FIG. Of the reference numerals shown in FIG. 3, elements having the same reference numerals as those described above represent the same elements. The multi-channel solid film ion sensor shown in FIG. 3 is formed with sensitive films 19a, 19b, and 19c manufactured by the same manufacturing method as the sensitive film 19 shown in FIG. This multi-channel solid film ion sensor is a solid film sensor having a shape in which the lead wire 15 is led out from below the electrically insulating layer. By using different functional film agents, solid film sensors having different functional films can be produced.

  Using the same functional film manufacturing method as in the example of FIG. 2 and the example of FIG. 3, a multi-channel solid film type sensor having a shape that leads out from the template 14 to the outside can be manufactured. . FIG. 4 is a diagram for explaining a method of manufacturing a multi-channel solid film type sensor in which the lead wire 20 is led out from the template 14. FIG. 4A is a front sectional view of the solid membrane ion sensor, and FIG. 4B is a side sectional view of the solid membrane ion sensor. Here, FIG. 4A is a cross-sectional view taken along the chain line cd of the solid film ion sensor of FIG. A polymer matrix layer (not shown) is provided on the upper part of the template 14 shown in FIG. 4A. By supplying the functional film agent 4 to the polymer matrix layer, a multi-channel solid film type sensor can be obtained. Manufactured. Elements having the same reference numerals as those described above in FIG. 4 are the same as those described above.

  A multi-channel solid film ion sensor having a shape in which the lead wire 20 is drawn from the side includes a template 14 having a space having a flat shape in the horizontal direction of the cross section, and an electrically insulating layer provided in the space. 17, a silver / silver halide layer 16 provided on the upper side of the electrical insulating layer 17 and on the right side of the cross section, and a silver / silver halide layer 16 connected to the silver / silver halide layer 16 and provided on the left side of the upper cross section of the electrical insulating layer 17. Lead wire 20. Accordingly, as shown in FIG. 4B, the multi-channel solid film ion sensor includes different sensitive films 19a, 19b, 19c, 19d manufactured by the same manufacturing method as the sensitive film 19. 19e is formed.

<Application example 2 of functional film production method>
Fabrication method of field effect transistor type sensor>
The manufacturing method of the functional film or the sensitive film of the field effect transistor type sensor is basically the same as the manufacturing method of the functional film of the solid film type sensor shown in FIG. FIG. 5 is a diagram showing a basic structure of a field effect transistor type sensor manufactured by using the method for manufacturing a functional film according to Application Example 2. The field effect transistor includes a substrate 21, a source region 22, a drain region 23 and a channel formation region 24 formed on the substrate 21, a first gate insulating film 25 provided on the substrate 21, A second gate insulating film 26 made of a material different from the material of the first gate insulating film 25 provided on the first gate insulating film 25, and provided on the second gate insulating film 26 A template 27 and a gate electrode portion 28 formed on the second gate insulating film 26 and surrounded by the template 27 are provided.

  In the gate electrode portion 28 of the field effect transistor shown in FIG. 5, a sensitive film can be formed using the same functional film manufacturing method as in Application Example 1. Specifically, the same functional film or sensitive film as the solid film sensor [FIG. 2A], or a mixed functional film or sensitive film mixed with the polymer matrix layer 18 [FIG. )] Is formed, the sensitive film 29 of FIG. 5 is obtained. A substance that interacts with a substance to be detected is fixed to the functional film (sensitive film) 29 formed in the gate electrode part 28, and serves as a sensing part of the detection sensing part gate of the field effect transistor type sensor. To play a role.

  In addition, a multi-channel field effect transistor type sensor having a different sensitive film can be produced using the above-described method for producing a sensitive film, similarly to the example of FIG. 3 and the example of FIG. 4B.

<Application example 3 of functional film production method>
Manufacturing method of crystal unit>
The manufacturing method of the functional film or the sensitive film used for the quartz resonator is basically the same as the manufacturing method of the functional film (sensitive film) of the solid film type sensor shown in FIG. In this case, a uniform type functional film or sensitive film similar to the solid film type sensor (FIG. 2) or a mixed type functional film mixed with a polymer matrix or the like on the surface of the vibrator type detection transducer of the crystal unit A sensitive film may be formed.

<Application example 4 of functional film production method>
Method for producing metal or semiconductor thin film>
When manufacturing a metal thin film or a semiconductor thin film, the process 1-the process 4 shown in FIG. 1 are needed. Furthermore, the process 4 is a sintering process, and in order to produce a metal thin film or a semiconductor thin film on the substrate, a fire-resistant substrate (for example, a ceramic substrate, a glass substrate, etc.) that is not easily deformed even when sintered is used. Use. The template is used as a mold for a metal thin film or a semiconductor thin film. When the template is not required after the thin film is formed, a polymer material that can be removed by sintering may be used as a template for the metal thin film or the semiconductor thin film.

  Referring to FIG. 1, in the functional film manufacturing method according to this application example 4, metal nanoparticles and fine particles or semiconductor nanoparticles and fine particles are dispersed on a refractory substrate 1 having a polymer matrix layer 2. Step 1 for supplying the functional film agent 4, Step 2 for diffusing the functional film agent 4 into the polymer matrix layer 2 and dispersing the metal nanoparticles and fine particles, or the semiconductor nanoparticles and fine particles, and the metal Step 3 for forming functional film 4 in which nanoparticles or fine particles of semiconductor or semiconductor nanoparticles or fine particles are dispersed, and Step 4 for sintering functional film 4 to remove polymer matrix and other organic substances Consists of. By passing through these steps 1 to 4, the metal thin film or the semiconductor thin film in the application example 4 is produced.

  When a metal thin film or a semiconductor thin film is produced, a water-soluble or water-insoluble polymer material can be used for the polymer matrix layer 2 depending on the type of the functional film agent 4. When metal nanoparticles or fine particles, or semiconductor nanoparticles or fine particles are dispersed in the functional film agent 4 in an aqueous solution, a water-soluble polymer material may be used as the polymer matrix layer 2. On the other hand, when these metal nanoparticles or fine particles, or semiconductor nanoparticles or fine particles are dispersed in the functional film agent 4 made of a nonaqueous solvent such as an organic solvent or an ionic liquid, a water-insoluble polymer material is used. Use it. When a polymer gel is used for the polymer matrix layer 2, a functional film agent that can be absorbed or released by the polymer gel when the polymer gel swells or contracts or when the polymer gel undergoes a phase transition 4 may be used, or the functional film agent 4 confined in the network structure of the polymer gel may be used.

  In addition, when using a polymer sheet or a polymer gel sheet in which gold fine particles or gold fine particles modified with a functional substance are dispersed as a sensor sheet, the sensor sheet can be produced by performing the production steps up to step 3. Good.

  Hereinafter, the manufacturing method of the functional film of the present invention will be described in detail with reference to specific examples.

(Example 1)
In Example 1, a solid membrane type potassium ion selective electrode (ISE) was prototyped and evaluated as the solid membrane type sensor shown in FIG.

  As the substrate 1 shown in FIG. 1, a silver wire surrounded by a resin and silver / silver chloride (diameter: 1.6 mm) were used. As the polymer matrix layer 2, a porous thin film of polyvinyl chloride (PVC) having an average pore diameter of 10 μm and a film thickness of 20 μm was used. As the template 3, a template composed of a Surlyn (registered trademark) resin layer having a thickness of 10 μm and a polyester layer having a thickness of 65 μm was used. Surlyn (registered trademark) resin is provided on the substrate 1 side, that is, on the silver / silver chloride electrode side. The polymer matrix layer 2 surrounded by the template 3 was circular and had a diameter of 4 mm. The template 3 is firmly bonded to the substrate 1 side with an adhesive Surlyn (registered trademark) resin.

  Functional film agent 4 includes potassium ion-sensing valinomycin (functional substance), plasticizer dioctyl adipate (DOA) that softens polyvinyl chloride, and anion exclusion agent potassium tetratraphenylborate (K-TPB). And an organic solvent tetrahydrofuran (THF).

  In the film formation, the functional film agent 4 was injected into the PVC layer as the polymer matrix layer 2 by using an automatic injection device manufactured in-house. After the injection of the functional film agent 4, at room temperature, the functional film agent 4 was vibrated longitudinally while hitting the work table so that the template 3 did not overflow. Thereafter, the PVC of the polymer matrix layer 2 into which the functional film agent 4 was injected melted and became transparent. After a while, it was observed that the membrane became hard due to the evaporation of tetrahydrofuran, and the micropores having a diameter of 10 μm were blocked by the functional membrane 7 (or the sensitive membrane 7). The functional film agent 4 can be injected into the region of the polymer matrix layer 2 surrounded by the template 3 several times. Finally, the content of the plasticizer contained in the functional film agent 4 so that the content of the plasticizer DOA contained in the functional film agent 4 is twice that of PVC as the polymer matrix layer 2. The supply amount of the functional film agent 4 was adjusted.

The potassium ion selective electrode prepared by the method as described above was left to dry for one day. Further, after aging the potassium ion selective electrode with 1 × 10 ⁻⁴ M KCl aqueous solution, a calibration curve for potassium ions was measured at room temperature (about 25 ° C.) using a standard solution not containing interfering ions. The sensitivity slope value was obtained. Further, using a standard solution containing sodium ions (0.15 M) as interfering ions, a calibration curve for potassium ions was measured, and a selectivity coefficient of potassium ions relative to sodium ions was determined by a mixing method. The ISE calibration curve measurement method is in accordance with the ISE standard measurement method. In the standard solution, the standard junction solution is a double-junction type silver / silver chloride electrode (outer cylinder solution: ammonium nitrate) as a reference electrode. The potential (E) between was measured. When the activity coefficient can be regarded as 1, the potential is proportional to the logarithm of the concentration [K ⁺ ] of the potassium ion, which is the target ion, as shown in the following formula (1).

E = E. + (2.303RT / nF) log [K ⁺ ] (1)
Where E. Is a constant determined by the electrode configuration, R is a gas constant, T is an absolute temperature, n is an ionic valence, and F is a Faraday constant. When the same sensitive membrane is used according to the equation (1), E increases with increasing potassium ion concentration of the sample solution at a constant temperature. Therefore, a calibration curve for potassium ions can be obtained by measuring potentials in standard solutions having different potassium ion concentrations.

As a result of measuring a calibration curve for potassium ions using a standard solution that does not contain interfering ions, a linear calibration curve was obtained in the concentration range of potassium ions from ¹ × 10 ⁻⁵ M to ¹ × 10 ⁻¹ M. The slope value was 58 mV / decade. In addition, using a standard solution containing sodium ions (0.15M) as interfering ions, a calibration curve of potassium ions was measured, and the selectivity coefficient of potassium ions relative to sodium ions was determined by a mixing method. (LogK _KNa ) was -4.

(Example 2)
In Example 2, a film formation method similar to that of Example 1 was used to manufacture a potassium ion sensitive field effect transistor (ISFET), which is one of the field effect transistor type sensors shown in FIG. And evaluated. The difference from the example of the first embodiment is that the gate electrode portion 28 of the electric effect transistor type sensor is used as the substrate 1. A potassium ion functional film or sensitive film was formed on the gate electrode to produce a potassium ion ion sensitive field effect transistor (ISFET).

In the same manner as in Example 1, the potassium ion ISFET prepared by the above method was left to dry for one day. Further, after aging the potassium ion selective electrode with 1 × 10 ⁻⁴ M KCl aqueous solution, a calibration curve for potassium ions was measured at room temperature (about 25 ° C.) using a standard solution not containing interfering ions. The sensitivity slope value was obtained. Further, using a standard solution containing sodium ions (0.15 M) as interfering ions, a calibration curve for potassium ions was measured, and a selectivity coefficient of potassium ions relative to sodium ions was determined by a mixing method.

When an ISFET is used, unlike the ISE measurement principle, the detection target substance is detected using the modulation principle of the drain current caused by the change in the interface potential of the gate electrode. A sensing gate for detection is used as the gate electrode of the ISFET, and the sensing gate for detection is a gate electrode portion 28 which is a gate body and a functional film which is a sensing portion (interaction sensing portion with a detection target substance). Sensitive membrane). When an interaction occurs between the sensitive part and the sample in the sensitive part (sensitive film) of the sensing gate for detection, a change in the gate potential of the gate electrode part 28 as the sensing gate is caused, followed by a change in the gate potential. As a result, the drain current is modulated. For example, the sensitive film of a potassium ion ISFET serves as a sensing part, and potassium ions are taken into the sensitive film, thereby causing a change in the interface potential of the sensing gate and causing a modulation of the drain current _ID . Therefore, the conditions are set so that the voltage V _DS between the drain electrode and the source electrode and the drain current _ID are constant, and the change in the interface potential of the gate electrode is directly measured as the change in the output voltage (VGS) of the meter. The A schematic diagram of the ISFET measurement circuit is shown in FIG. FIG. 6 is a diagram showing an outline of a circuit for measurement of a field effect transistor type sensor used in the method for producing a functional film according to Example 2 of the present invention. A functional film 31 is formed on the gate electrode portion 30. 32 represents a source electrode, 33 represents a drain electrode, 34 represents a reference electrode, and 35 represents a sample.

In the measurement of ISFET characteristics evaluation of potassium ion in Example 2, the voltage V _DS between the drain electrode and the source electrode is fixed to 5 V, the drain current _ID is fixed to 100 μA, and the potassium ion concentration in the standard solution is determined. The output potential due to the change was measured.

As a result of measuring a calibration curve of potassium ions using a standard solution not containing interfering ions, a linear calibration curve was obtained in a potassium ion concentration range of ¹ × 10 ⁻⁶ M to ¹ × 10 ⁻¹ M, and a sensitive slope was obtained. The value was 58 mV / decade. In addition, using a standard solution containing sodium ions (0.15M) as interfering ions, a calibration curve of potassium ions was measured, and the selectivity coefficient of potassium ions relative to sodium ions was determined by a mixing method. (LogK _KNa ) was -4.

(Example 3)
In Example 3, a functional film in which gold nanoparticles were dispersed was prepared using a polymer gel as the polymer matrix layer 2 and a functional film agent 4 in which gold nanoparticles were dispersed in an aqueous solution.

  As the substrate 1 shown in FIG. 1, a quartz substrate was used. As the polymer matrix layer 2, Meviol Gel (registered trademark), which is a polymer gel having a film thickness of 30 μm, was used. As the template 3, a template composed of a Surlyn (registered trademark) resin layer having a thickness of 10 μm and a polyester layer having a thickness of 100 μm was used. Surlyn (registered trademark) resin is provided on the substrate 1 side, that is, on the quartz substrate side. The polymer matrix layer 2 was surrounded by a template, and the size of the polymer matrix layer 2 was 4 mm long and 2 mm wide. The template 3 is firmly bonded to the substrate 1 side with an adhesive Surlyn (registered trademark) resin. As the functional film agent 4, a citric acid aqueous solution in which gold nanoparticles having an average particle diameter of 3 nm were dispersed was used.

  In film formation, the functional film agent 4 was injected into Meviol Gel (registered trademark), which is the polymer matrix layer 2, at room temperature (25 ° C.) using an automatic injection device manufactured in-house. After injecting the functional film agent 4, while cooling to 10 ° C. or lower, melol gel (registered trademark) is made into a sol, and the substrate 1 is hit against the work table vertically so that the functional film agent 4 does not overflow from the template 3. By vibrating, the functional film agent 4 was diffused in the sol-like meviol gel (registered trademark). Next, by heating again to 25 ° C. or higher, Meviol Gel (registered trademark) was gelled, and a functional film in which gold nanoparticles were dispersed was produced.

  The functional film can be further sintered to remove Meviol Gel (registered trademark) and citric acid contained in the functional film agent 4 to produce a gold thin film.

Example 4
In Example 4, the polymer matrix layer 2 is made of polyvinyl alcohol (PVA), which is a water-soluble polymer, and the functional film agent 4 in which gold nanoparticles are dispersed in an aqueous solution is used. A dispersed functional film was prepared.

  As the substrate 1 shown in FIG. 1, a quartz substrate was used. As the polymer matrix layer 2, polyvinyl alcohol (PVA), which is a water-soluble polymer material having a thickness of 20 μm, was used. As the template 3, a template composed of a Surlyn (registered trademark) resin layer having a thickness of 10 μm and a polyester layer having a thickness of 95 μm was used. Surlyn (registered trademark) resin is provided on the substrate 1 side, that is, on the quartz substrate side. The polymer matrix layer 2 was surrounded by the template 3 and the size of the polymer matrix layer 2 was 4 mm long and 2 mm wide. The template 3 is firmly bonded to the substrate 1 side with an adhesive Surlyn (registered trademark) resin. As the functional film agent 4, an aqueous citric acid solution in which gold nanoparticles having an average particle diameter of 3 nm were dispersed was used.

  In film formation, the functional film agent 4 was injected into Meviol Gel (registered trademark), which is the polymer matrix layer 2, at room temperature (25 ° C.) using an automatic injection device manufactured in-house. After a while after the injection of the functional film agent 4, the polyvinyl alcohol starts to dissolve. Next, the functional film agent 4 was diffused in the polyvinyl alcohol layer by longitudinally vibrating the substrate 1 against the work table so that the functional film agent 4 did not overflow from the template 3. Thereafter, the functional film 7 in which the water was evaporated and gold nanoparticles were dispersed was produced by heating.

  The functional film 7 containing gold nanoparticles is added again to the functional film after evaporation of water, and the above-described method is repeated to form the functional film 7 having high-density gold nanoparticles. Can be produced.

  Further, the functional film can be further sintered to remove a polyvinyl alcohol layer or the like, thereby producing a gold thin film (functional film 9).

  In addition, in the method for producing a functional film according to the present embodiment, a honeycomb film, a nonwoven fabric made of a polymer material, or a nonwoven fabric made of a polymer-coated metal thin wire can be used instead of the polymer thin film. Then, functional films having various shapes can be formed. When the honeycomb film is used, the functional thin film can be formed in the micropores of the honeycomb film by completely dissolving the honeycomb film or by partially dissolving the peripheral portions of the micropores of the honeycomb film. When a non-woven fabric is used, a non-woven fabric made of a polymer material or a non-woven fabric made of a polymer-coated metal fine wire can be used. In addition, when forming a functional film using a nonwoven fabric, you may leave a fine space | gap in a functional film.

  In the manufacturing method of the functional film using the prior art, the manufacturing process is complicated, the manufacturing conditions are not mild, and the functional film that can be manufactured is limited to materials suitable for various manufacturing methods, and the manufacturing is performed. Fewer types of functional membranes are possible. According to the method for producing a functional film according to the present embodiment, the types of functional films that can be produced are not limited. Moreover, according to the demand for a small-sized disposable sensor or a living body embedded type sensor, a functional film can be rapidly produced in a minute region.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

It is a flowchart for demonstrating the manufacturing method of the functional film which concerns on one Embodiment of this invention. It is a figure which shows an example of the manufacturing method of the functional film which concerns on the application example 1 of this invention. It is sectional drawing of the multi-channel solid film type | mold ion sensor manufactured using the manufacturing method of the other functional film | membrane which concerns on the application example 1 of this invention. It is a figure for demonstrating the manufacturing method of another functional film which concerns on the application example 1 of this invention. It is a figure which shows the basic structure of the field effect transistor type sensor manufactured using the manufacturing method of the functional film which concerns on the application example 2 of this invention. It is a figure which shows the outline of the circuit for a measurement of the field effect transistor type sensor used for the manufacturing method of the functional film which concerns on Example 2 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 2,18 ... Polymer matrix layer, 3, 14, 27 ... Template, 4 ... Functional film agent, 5 ... Supply part, 6 ... Diffusion part, 7, 9, 29, 31 ... Functional film, DESCRIPTION OF SYMBOLS 8 ... Immobilization part, 10 ... Sintering part, 11-13 ... Apparatus, 15, 20 ... Lead wire, 16 ... Silver / silver halide layer, 17 ... Electrical insulation layer, 19 ... Sensitive film (functional film) 21 ... substrate, 22 ... source region, 23 ... drain region, 24 ... channel forming region, 25 ... first gate insulating film, 26 ... second gate insulating film, 30 ... gate electrode portion, 32 ... source electrode, 33 ... Drain electrode, 34 ... Reference electrode, 35 ... Sample.

Claims (9)

A first step of supplying a functional film containing a functional substance and a solvent for dissolving or expanding the polymer matrix layer to the polymer matrix layer disposed on the substrate;
A second step of dispersing the functional substance in the polymer matrix layer by diffusing the functional film agent into the polymer matrix layer;
A third step of solidifying the polymer matrix layer in which the functional substance is dispersed in the second step to form a functional film;
A method for producing a functional film, comprising:   The functional film according to claim 1, wherein in the third step, the polymer matrix layer containing the functional substance is concentrated, dried, or gelled to harden the polymer matrix layer. Method.   The method for producing a functional film according to claim 1, further comprising a fourth step of firing the functional film. The functional film agent supplied in the first step includes metal nanoparticles, metal particles, semiconductor nanoparticles, or semiconductor particles,
In the fourth step, the polymer matrix layer in which the functional film agent containing the metal nanoparticles, metal fine particles, semiconductor nanoparticles, or semiconductor fine particles is dispersed is sintered. Item 4. A method for producing a functional film according to Item 3.   In the first step, a polymer thin film, a polymer fiber or porous thin film, or a polymer gel thin film is used as the polymer matrix layer, and the substrate on which the polymer matrix layer is formed is used. The method for producing a functional film according to claim 1, wherein the functional film is used.   2. The first step is characterized in that a solid-type electrode of a solid film type sensor, a gate electrode of a field effect transistor type sensor, or a vibrator-type detection transducer of a crystal vibrator is used as the substrate. A method for producing a functional film.   2. The functional film according to claim 1, wherein in the first step, the functional film agent includes a liquid that does not include a component of the polymer matrix layer and dissolves or expands the polymer matrix layer. Manufacturing method.   In the third step, the functional film agent is diffused into the polymer matrix layer using any one or more of temperature, vibration, light, ultrasonic wave, or magnetic field. The method for producing a functional film according to claim 1.   The method for producing a functional film according to claim 1, wherein in the first step, a template is disposed on the polymer matrix layer, and the functional film agent is applied through the template.

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