JP2012103098A - Manufacturing method of microchip with electrode, and microchip with electrode manufactured by the manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a microchip with electrodes in which adhesion of two substrates including electrode portions can be firmly performed without remaining of foreign matter in a flow passage at all and the manufacturing cost can be reduced, and to provide the microchip with electrodes manufactured by the manufacturing method.SOLUTION: Disclosed is the manufacturing method of a microchip with electrodes which is manufactured by joining two substrate members with each other and has at least the flow passage and the electrodes connected to the flow passage on the joining surface. The manufacturing method includes: a step of joining the two substrate members with each other; a first joining step of joining portions other than the vicinity of the electrodes of the substrate members; and a second joining step of joining the portions in the vicinity of electrodes of the substrate members. The microchip is provided which is manufactured by the manufacturing method.

Description

  The present invention relates to a method of manufacturing a microchip having an electrode in a part of a flow path, and a microchip with an electrode manufactured by this manufacturing method.

  A micro test chip that uses microfabrication technology to form fine channels and circuits on a substrate member, and inspects chemical reactions, separation, and analysis of specimens such as nucleic acids, proteins, and blood in a minute space An apparatus called a micro analysis chip, or μTAS (Micro Total Analysis Systems) has been put into practical use (hereinafter, these are referred to as a microchip). Advantages of such a microchip include a reduction in the amount of sample and reagent used or the amount of waste liquid discharged, and the realization of a low-cost and portable analysis system.

  A microchip is manufactured by bonding two substrate members that are finely processed to at least one substrate member. A channel groove and a liquid reservoir are formed on the substrate member by microfabrication, and a through-hole penetrating in the thickness direction is formed at a position on the substrate member corresponding to the start and end of the groove. A specimen or a reagent is injected from the through-hole and an inspection is performed.

  Conventionally, glass substrates have been used for microchips. However, in recent years, development of inexpensive and relatively easy-to-dispose resin microchips has been desired because of their unsuitability for mass production and high costs. ing. In the case of a resin member, one substrate member may be a plate member or a film member. Moreover, it can also be comprised with two board | substrate members of resin and glass.

  As a method of joining resin members, a method using an adhesive, a method in which a resin surface is melted with a solvent, a method using ultrasonic fusion, a method using laser fusion, a flat plate shape or a roll shape And a method using thermal bonding (thermal fusion) with a pressure device. In particular, thermal bonding can be performed at a low cost, so it is suitable as a bonding method based on mass production.

  One type of such microchip is a microchip having electrodes. By applying a voltage between the electrodes provided at two locations in the flow path, an object such as a specimen can be separated by electrophoresis or analyzed. Electrophoresis in the biochemical field has been established as a method for measuring protein mobility by carrier-free electrophoresis using an aqueous solution, but recently a carrier (gel or polymer solute) has been used. Electrophoresis is used. In carrier electrophoresis, a “molecular sieving effect” works, in which macromolecules such as DNA and proteins are obstructed by carrier molecules, and the larger the molecular weight, the more difficult it moves, so it is used for protein analysis and DNA base sequencing. . For example, in DNA analysis, a buffer solution containing a polymer is injected under pressure from a through hole into a flow path, and then a fluorescently labeled DNA sample is injected. Then, electrophoresis is performed by applying a high voltage between the two electrodes, and a DNA sample is detected by a fluorescence detector.

  In Patent Document 1, one glass substrate having a fine channel formed on the surface thereof is aligned and overlapped on the other glass substrate having an electrode formed on the surface so that the electrode and the fine channel are opposed to each other. A step of aligning, a step of intruding a UV curable adhesive between the one glass substrate and the other glass substrate, a step of removing the UV curable adhesive that has entered the fine flow path, and irradiating with UV light There is disclosed a method of manufacturing a glass microchip substrate with an electrode including the step of:

  Patent Document 2 proposes a resin microchip in which an acrylic resin film, such as polymethyl methacrylate, is thermally fused to a substrate made of an acrylic resin such as polymethyl methacrylate. Although this patent document 2 has an electrode for electrophoresis, the electrode is formed on the film side by a through-hole method, and is placed in the through hole of the resin substrate and sandwiched between the resinous substrate and the resinous film. It is configured not to be.

JP 2008-170349 A JP 2000-310613 A

  In Patent Document 1, the removal of the UV curable adhesive that has entered the fine flow path is removed by suction with a micropipette or a diaphragm pump. However, it is not easy to completely remove the UV curable adhesive that has entered the flow path. If it cannot be removed by suction, it will be dissolved in a solvent, but if the adhesive or solvent remains in the flow path, there is a risk of hindering analysis performance.

  The formation of the through-hole type electrode of Patent Document 2 has a complicated process and requires a highly accurate assembly technique in order to position the electrode in the through hole of the resinous substrate. Therefore, there is a drawback that the configuration of the microchip becomes incomplete or the manufacturing cost is increased.

  Further, when two resin members are bonded, if only two substrates are bonded, it can be bonded relatively easily by a general bonding method, but the electrode is sandwiched between the two substrates. In the case of a structure, since the electrode is made of a material different from that of the substrate, a bonding failure is likely to occur. If there is such a bonding failure, current leakage or liquid leakage occurs, which adversely affects the analysis performance.

  In view of such a situation, the present invention does not leave any foreign matter in the flow path, can firmly bond the two substrates including the electrode portion, does not leak current, does not leak liquid, and has a manufacturing cost. It is an object of the present invention to provide a method for manufacturing a microchip with an electrode that can be made inexpensively, and a microchip with an electrode manufactured by this manufacturing method.

The above object can be achieved by the following configuration. That is,
1. A method of manufacturing a microchip with an electrode, which is manufactured by bonding two substrate members, and has at least a flow channel and an electrode connected to the flow channel on a bonding surface,
The flow path is formed on a surface that becomes one joining surface of the two substrate members, and the electrode is formed on the surface that becomes the one joining surface or the joining surface of the other substrate member. A substrate fabrication process for fabricating a single substrate member;
A first bonding step of bonding portions other than the vicinity of the electrodes of the two substrate members;
A second bonding step of bonding portions in the vicinity of the electrodes of the two substrate members;
The manufacturing method of the microchip with an electrode characterized by implementing.
2. 2. The microchip with electrodes according to 1 above, wherein the first bonding step is performed by any one of thermal bonding, bonding with an adhesive, laser bonding, ultrasonic bonding, and bonding with an organic solvent. Manufacturing method.
3. 3. The method for manufacturing a microchip with electrodes according to 1 or 2, wherein the second bonding step is performed by any one of laser bonding, ultrasonic bonding, and bonding using an organic solvent.
4). At least one of the said board | substrate members is resin, The manufacturing method of the microchip with an electrode as described in any one of said 1 to 3 characterized by the above-mentioned.
5. 5. The method for manufacturing a microchip with electrodes according to 4, wherein the resin substrate member is either a plate member or a film member.
6). Any one of the above 1 to 5 is characterized in that, following the substrate manufacturing step, a pretreatment step of performing surface modification by irradiating at least one of the bonding surfaces of the two substrate members with energy rays is performed. The manufacturing method of the microchip with an electrode as described in a term.
7). 7. The method for producing a microchip with electrodes as described in 6 above, wherein the irradiation with the energy beam is at least one of excimer light, corona discharge, and plasma discharge.
8. A method of manufacturing a microchip with an electrode, which is manufactured by bonding two substrate members, and has at least a flow channel and an electrode connected to the flow channel on a bonding surface,
A step of producing the two substrate members, including a step of forming a liquid stop groove at a position surrounding the flow path of the substrate member on which the flow path is formed or the opposite substrate member. A substrate manufacturing process;
A first bonding step of bonding the substrate member by applying an adhesive or an organic solvent to the outside of the liquid stop groove;
A second joining step for joining portions in the vicinity of the electrodes of the substrate member;
The manufacturing method of the microchip with an electrode characterized by performing by these.
9. 9. The method for manufacturing a microchip with electrodes as described in 8 above, wherein the second bonding step is performed by any one bonding method of laser bonding and ultrasonic bonding.
10. 10. The method for manufacturing a microchip with electrodes according to 8 or 9, wherein at least one of the substrate members is made of a resin.
11. 11. The method for producing a microchip with an electrode according to 10 above, wherein the resin substrate member is either a plate-like member or a film-like member.
12 Any one of the above-mentioned 8 to 11, wherein a pre-processing step of performing surface modification by irradiating energy rays to at least one of the bonding surfaces of the two substrate members is performed subsequent to the substrate manufacturing step. The manufacturing method of the microchip with an electrode as described in a term.
13. 13. The method for producing a microchip with electrodes as described in 12 above, wherein the irradiation with the energy beam is at least one of excimer light, corona discharge, and plasma discharge.
14 14. A microchip with an electrode manufactured by the manufacturing method according to any one of 1 to 13 above.

  According to the microchip manufactured by joining the two substrate members of the present invention, no foreign matter remains in the flow path, and the two substrates including the electrode portion can be firmly joined, and current leakage and liquid can be obtained. It is possible to provide a method of manufacturing a microchip with an electrode that does not have a leak and can be manufactured at a low cost, and a microchip with an electrode manufactured by this manufacturing method.

The figure which shows the form before joining of the microchip of 1st Embodiment which concerns on this invention. The figure which shows the form after joining of the microchip of 1st Embodiment which concerns on this invention. The figure which shows the flow of each process of the microchip manufacturing method of embodiment of this invention. The figure which shows the form after the 1st joining process and the 2nd joining process of the microchip of the modification which concerns on this invention. The figure which shows the form of the microchip of the 2nd Embodiment of this invention. The figure which shows the modification of the electrode part which concerns on this invention. The figure which shows another modification of the electrode part which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a form before bonding of the microchip 1 according to the first embodiment of the present invention. FIG. 1 (a) is a plan view of the bonding surface side of the first substrate 2, and FIG. 1 (b). FIG. 1C is a plan view of the bonding surface side of the second substrate 3, FIG. 1C is a sectional view taken along line XX of the first substrate 2, and FIG. 1D is a sectional view taken along line YY of the second substrate 3. .

  In the first embodiment, the two substrate members are both made of a transparent resin plate, the substrate having the through hole 2a and the flow path 2b is the first substrate 2, and the substrate having the electrode 4 is the second substrate 3. Call it.

  The first substrate 2 has four through holes 2a penetrating in the thickness direction, a flow path 2b, and four depressions 2c connecting the through holes 2a and the substrate side portions. The flow path 2b is a horizontal flow path that connects the upper and lower through holes 2a in FIG. 1 and a horizontal direction that connects the left and right through holes 2a in FIG. It is comprised by the flow path, and both flow paths cross | intersect. The recess 2 c is a recess into which the electrode 4 enters when bonded to the second substrate 3, and is formed slightly larger than the electrode 4. Depending on the thickness of the electrode 4 and the material of the substrate member, this depression may not be necessary.

  On the other hand, on the second substrate 3, four electrodes 4 are formed at positions extending from the position corresponding to the through hole 2a indicated by the broken line to the side of the substrate.

  2A and 2B are diagrams showing a state of the microchip 1 obtained by bonding the first substrate 2 and the second substrate 3 described above. FIG. 2A is a plan view and FIG. It is sectional drawing in Z line.

  The microchip 1 has a through hole 2a on its upper surface, a flow path 2b linking the through hole 2a to the joint surface portion of both substrates, and an electrode 4 partially exposed on the side of the through hole 2a and the microchip. It becomes the form which has.

  The through-hole 2a is a connection part between the flow path 2b and the outside, and introduces and stores a sample, a reagent, a gel, or a buffer solution (hereinafter, materials introduced into the flow path are collectively referred to as “sample etc.”). Or a hole for discharging. The shape of the through hole 2a may be various shapes other than a circular shape and a rectangular shape. A tube or nozzle provided in the analyzer is connected to the through-hole 2a, and a sample or the like is introduced into or discharged from the flow path 2b through the tube or nozzle. A priming pump, a syringe pump, or the like may be connected to the through hole 2a to assist in the introduction or discharge of the specimen. Moreover, although the through-hole 2a is an example provided in the edge part of the flow path 2b in FIG. 1, FIG. 2, it can also be provided in the middle of the flow path 2b.

  The electrode 4 is connected to an external power source, and applies voltage to a sample or the like in the flow path 2b to perform electrophoresis or the like.

  The above is the structure and operation of the microchip 1 of the first embodiment. As a modification, the first substrate 2 or the second substrate 3 or both can be formed of a film. Furthermore, at least one of the substrate members can be made of a material such as silicon or quartz glass. However, a plate-like or film-like resin substrate is preferred from the viewpoint of ease of molding and disposal.

  By the way, there is a microchip having a three-layer structure in which a polyimide resin layer is formed on a flat substrate, a flow path is formed in the polyimide resin by photoetching, and another flat plate substrate is joined thereto. It is assumed that the present invention includes a substrate having the flow paths as one substrate member of the present invention. Moreover, it is not limited to the said description in which substrate member a flow path, a through-hole, and an electrode are formed.

  The resinous materials for the first substrate 2 and the second substrate 3 are required to have good moldability (transferability, releasability), high transparency, and low autofluorescence with respect to ultraviolet rays and visible light. As mentioned. For example, a thermoplastic resin is used for the first substrate 2 and the second substrate 3. Examples of the thermoplastic resin include polycarbonate, polymethyl methacrylate, polystyrene, polyacrylonitrile, polyvinyl chloride, polyethylene terephthalate, nylon 6, nylon 66, polyvinyl acetate, polyvinylidene chloride, polypropylene, polyisoprene, polyethylene, polydimethyl. It is preferable to use siloxane, cyclic polyolefin or the like. It is particularly preferable to use polymethyl methacrylate and cyclic polyolefin. Note that the same material may be used for the first substrate 2 and the second substrate 3, or different materials may be used.

  The outer shape of the microchip 1 may be any shape that can be easily handled and analyzed, and is preferably a square or a rectangle. As an example, the size may be 10 mm square to 200 mm square.

  Moreover, the thickness of the 1st board | substrate 2 and the 2nd board | substrate 3 is about 0.5 mm-10 mm in the case of a plate-shaped member, respectively, and is about 0.01 mm-0.5 mm in the case of a film-shaped member. Of course, both thicknesses may be the same or different.

  The shape of the flow path 2b is within the range of 1 μm to 1000 μm in both width and depth in consideration of the fact that the amount of analysis sample and reagent used can be reduced, the production accuracy of the mold, transferability, releasability, etc. Although it is preferably a value, it is particularly preferably about 10 μm to 200 μm. What is necessary is just to determine the width | variety and depth of the flow path 2b according to the use of the microchip 1. FIG. Moreover, the cross-sectional shape of the flow path 2b may be rectangular or curved.

The electrode 4 is applied with a high voltage of about 5000 V to 6000 V, the surface resistance is in the range of 15 Ω / m ^{2 to 20} Ω / m ² , and the thickness is preferably about 1 μm to 30 μm. If the thickness is reduced, the resistance value is increased, so that a certain thickness is required to satisfy the required conductive performance. Electrode materials such as C, Au, Cu, and Ag are used as the electrode material, and when produced by methods such as screen printing, ink jetting, and coating, fine particles of these conductive materials are mixed with a binder. Used as a liquid or paste. The above-described method is a simple method and is useful for carrying out the present invention, but other manufacturing methods such as vapor deposition and sputtering can also be used.

Next, the manufacturing method of the microchip of this embodiment will be described. As shown in FIG. 3, the manufacturing method of this embodiment includes the following steps (1) to (4).
(1) First and second substrates are manufactured (substrate manufacturing process).
(2) A surface modification treatment is performed (pretreatment step).
(3) Joining portions other than the vicinity of the electrodes (first joining step).
(4) Joining the vicinity of the electrode (second joining step).
Each step will be described below in order.

[Substrate manufacturing process]
The substrate manufacturing process is a process up to the previous stage of bonding the substrate members. When the substrate member is a resin plate-like member, the first substrate 2 and the second substrate 3 are produced by a prepared mold such as injection molding or press molding. The 1st board | substrate 2 is shape | molded with the metal mold | die which has a type | mold which shape | molds a flow path, a through-hole, and a hollow. Since the second substrate 3 is a flat plate, it may be cut out to a predetermined size from a flat plate having a predetermined thickness.

  When the second substrate 3 is a resinous film-like member, the film-like member is manufactured by a known method such as a melt extrusion molding method, a solution casting method, or a calendar method, and cut into a predetermined size. Subsequently, an electrode 4 is formed on the film-like member to form a second substrate 3. The electrode 4 can be formed by the above-described methods such as screen printing, ink jetting, and coating.

[Pretreatment process]
When both substrates are formed, a surface modification treatment is applied to the joint surfaces. The surface modification treatment is not always necessary, but the bonding can be further strengthened in the subsequent bonding step. In particular, polyethylene, polypropylene, and the like having a small polarity have a low adhesive force, and thus surface modification treatment is effective.

  The surface modification treatment can be performed by energy ray irradiation treatment such as excimer light irradiation, plasma discharge, corona discharge, and the like. The substrate surface is activated by such energy beam irradiation to improve the adhesion.

[First joining step]
The first bonding step is a step of bonding portions other than the vicinity of the electrodes. Examples of the bonding method include thermal bonding, bonding with an adhesive, laser bonding, ultrasonic bonding, bonding with an organic solvent, and the like. Bonding with an adhesive and an organic solvent will be described in a second embodiment to be described later.

  Thermal bonding, laser bonding, and ultrasonic bonding are all made by melting a resin by heating and solidifying it by cooling, and can be applied when the resin material is a thermoplastic resin.

  In the thermal bonding, the first substrate 2 and the second substrate 3 are sandwiched by a heated hot plate using a hot press machine, and pressure is applied by the hot plate and held for a predetermined time, thereby bonding the two together. A hot roll machine can be used instead of the hot press machine.

  Laser bonding is performed by heating with a laser beam, and laser scanning is performed by condensing the laser beam on a bonding surface. The laser beam is condensed to melt the resin material on the bonding surface, and the two substrates are bonded. In addition, some resin materials originally contain a component that absorbs laser light, and if one resin has the property of absorbing light corresponding to the wavelength of the laser used, it will naturally generate heat at the bonding surface, Condensing light onto the joint surface is not essential. In the case of a resin material that does not contain a laser light absorbing component, a light absorbing dye that absorbs laser light is dispersed in at least one of the substrate members, or light is applied to the portion where the two resin substrates are joined (other than the vicinity of the electrodes). You may heat by the laser beam by the method of apply | coating an absorber. The laser intensity is about 0.1 W to 20 W, for example.

  In the ultrasonic bonding, strong frictional heat is generated on the bonding surfaces by fine ultrasonic vibration and pressure, and the resin is melted and bonded. In ultrasonic bonding, a vibrator composed of a piezoelectric element is vibrated at high speed, and the vibration energy is applied to the bonded surfaces by applying pressure to the first and second substrates superimposed via a resonator called a horn. Frictional heat is generated and the joint surfaces are welded in a very short time. For example, the frequency of the ultrasonic wave may be about 10 kHz to 50 kHz, and the welding time can be performed in 1 second or less.

  In addition, when a board | substrate member is not a thermoplastic resin, the below-mentioned adhesive bonding etc. are used.

  In this way, when the portions other than the vicinity of the electrodes of the microchip 1 can be joined in the first joining step, the joining in the vicinity of the electrodes is subsequently performed in the second joining step.

[Second joining step]
The second bonding step is a step of bonding portions near the electrodes. As a bonding method, thermal bonding, laser bonding, ultrasonic bonding, bonding with an organic solvent, or the like can be used.

  FIG. 4 is a diagram illustrating the microchip 11 after the first bonding step. FIG. 4A is a plan view of the microchip 11. This microchip 11 is the same as that shown in FIGS. 1 and 2, except that two electrodes 4 are provided adjacent to the upper side. The same as the chip 1. 4B is an enlarged plan view of the vicinity of the electrode 4, FIG. 4C is an enlarged side view of FIG. 4B viewed from the right side, and FIG. 4D is a partially enlarged view of the adjacent electrode 4. It is a top view. FIGS. 4E, 4F, and 4G are views showing a state after the second joining step at the portions corresponding to FIGS. 4B, 4C, and 4D, respectively.

  4B and 4C, an unjoined gap G1 exists in the vicinity of the electrode 4 after the first joining step. If such a gap G1 is left unattended, the specimen or the like may leak and hinder analysis performance. Further, as shown in FIG. 4D, if the unjoined portion G2 is formed across the two electrodes 4 between the two electrodes adjacent to each other, current leakage occurs when the specimen or the like is filled.

  The second joining step is a step of eliminating gaps G1 and unjoined portions G2 by completely joining the vicinity of such electrodes. FIGS. 4E, 4F, and 4G show the state after the second joining process at the portions corresponding to FIGS. 4B, 4C, and 4D, respectively. (The part where the gap disappears is indicated by a thick solid line.)

  When thermal bonding is used in both the first bonding step and the second bonding step, the vicinity of the electrode is completely bonded by changing the pressure and time of the thermal bonding in the second bonding step. The pressure and time for thermal bonding are appropriately set according to the type and thickness of the resin material, the electrode material, and the like.

  When laser bonding is used in the second bonding step, when the electrode and its vicinity are laser-scanned, the substance constituting the electrode absorbs the laser beam and generates heat, and the nearby resin is melted to fill the gap G1 and the unbonded portion G2. . In ultrasonic bonding, the corner of the electrode becomes a tip that receives vibration energy, and heat generation is concentrated so that the gap G1 and the unbonded portion G2 can be filled similarly.

  In bonding using an organic solvent, when an organic solvent that dissolves the resin is injected into the gap from the end of the microchip 1, the entire gap is reached by capillary action, or the resin is dissolved to fill the gap G1 and the unbonded portion G2. At this time, since other parts such as the flow path 2b are already joined, the organic solvent does not go to these parts and there is no influence.

  As described above, the first and second substrates are completely joined by joining the vicinity of the electrodes in the first joining process, and subsequently joining the vicinity of the electrodes in the second joining process. While being able to manufacture, desired analytical performance can be exhibited.

  The joining methods of the first joining process and the second joining process can be combined in various ways, and may be selected in consideration of the materials used.

  FIG. 5 is a diagram showing a second embodiment of the present invention. 5 (a) is a plan view of the microchip 21, FIG. 5 (b) is an enlarged plan view of an intersecting portion of the flow path 2b (circled portion in FIG. 5 (a)), and FIG. Sectional drawing and FIG.5 (d) are enlarged plan views at the time of providing a liquid reservoir in the electrode vicinity.

  The second embodiment is an example in which bonding is performed with an adhesive or an organic solvent in the first bonding step when a material that cannot be bonded by heating, such as thermosetting resin or glass, is used as the substrate material. Of course, it can also be applied to thermoplastic resins. In order to prevent an adhesive or an organic solvent from entering the flow path, the microchip 21 of the second embodiment is provided with a liquid stop groove 22 along the flow path 2b. As shown in FIGS. 5A to 5C, the liquid stop groove 22 is provided along the flow path 2 b and separated from the flow path 2 b by about 20 μm to 500 μm. The width and depth of the liquid retaining groove 22 may be set in consideration of the fluidity of the adhesive used.

  In this embodiment, since the vicinity of the electrode is bonded in the second bonding step, no adhesive or the like need be applied to the vicinity of the electrode. However, when it is desired to apply the adhesive or the like as close to the electrode as possible, FIG. As shown in (d), a liquid stop groove 23 surrounding the through hole 2 a may be provided and communicated with the liquid stop groove 22. The liquid stop groove 23 may have the same arrangement and dimensions as the liquid stop groove 22. Note that there is no problem in that the adhesive touches the electrode itself, and the adhesive is allowed to partially cover the electrode as long as the electrical connection with the terminal for applying a voltage is established. Accordingly, the liquid stop groove 23 may be formed up to the through hole.

  In FIG. 5, the liquid retaining grooves 22 and 23 are provided on the first substrate 2 side where the flow path 2b is provided, but may be provided on the second substrate 3 side. In short, it may be provided on the substrate on the side where the application surface faces upward when applying an adhesive or the like. That is, even when an adhesive or the like is applied, even if it spreads to the flow path side, it may flow into the liquid stop groove so as not to reach the flow path.

  Next, a microchip manufacturing method according to the second embodiment will be described.

[Substrate manufacturing process] [Pretreatment process]
The substrate manufacturing step is a step of creating a first substrate and a second substrate, and is the same as that of the first embodiment except that a liquid stop groove is provided. The pretreatment process is the same as that in the first embodiment.

[First joining step]
The first bonding step is a step of bonding two substrates by applying an adhesive or an organic solvent. The adhesive or organic solvent to be used is selected according to the type of substrate material. In this first joining step, an adhesive or the like is applied and joined to a region other than the region surrounded by the liquid stop groove, but even if it protrudes slightly, it is blocked by entering the liquid stop groove and does not enter the flow path side. Therefore, the flow path is not contaminated with an adhesive or the like.

[Second joining step]
The second joining step is a step of joining the vicinity of the electrode and the vicinity of the flow path, which are unjoined portions joined in the first joining step. In this step, methods such as thermal bonding, laser bonding, and ultrasonic bonding can be used. A specific method may be performed in the same manner as described in the first embodiment.

  Here, the electrode of FIG. 1 was sandwiched between two substrate materials and the end portion was only seen through the side portion, but a modified example in which this is easier to connect will be described with reference to FIGS. .

  6A is an enlarged plan view of the electrode portion, and FIG. 6B is a partial cross-sectional view thereof. In the microchip 31 of FIG. 6, at least a portion corresponding to the electrode of the first substrate 32 is made smaller than the second substrate 33, and the electrodes 34 are exposed on the second substrate 33 when the two substrates are joined. It is a configuration.

  On the other hand, FIG. 7 shows another modified example, FIG. 7 (a) is an enlarged plan view of an electrode portion, and FIG. 7 (b) is a partial sectional view thereof. In the modification of FIG. 7, two through holes 32a and 32b are provided in parallel, and the electrode 35 is formed so as to straddle the through holes 32a and 32b. The through-hole 32a on the side connected to the flow path 2b is used for introducing and discharging a specimen and the like, and the through-hole 32b is used for connecting a lead wire to the exposed electrode 35.

  In the electrode of FIG. 1, since there are few exposed portions at the end, processing such as soldering and connecting the conductive wire to this portion is necessary. However, the type of FIG. 6 is an electrode exposed with, for example, a clip-type conductive wire Can be used. Moreover, in the type of FIG. 7, the probe provided in the front-end | tip of conducting wire can be used by inserting in the through-hole 32b. Of course, a conductive wire may be soldered to the electrode in FIGS.

Example 1
Next, specific examples of the above-described embodiment will be described. Example 1 is a microchip having the structure shown in FIGS. 1 and 2, wherein the first substrate is a plate-like member and the second substrate is a film-like member.

  First, a transparent resin material polymethylmethacrylate (acrylic resin, manufactured by Asahi Kasei, Delpet 70NH) is injection-molded to form a plate-like member having an outer dimension of width 30 mm × width 20 mm × thickness 1 mm, width 30 μm, depth A first substrate 2 having a flow path 2b having a thickness of 30 μm and a plurality of through holes 2a having an inner diameter of 2 mm was produced.

  Further, a polymethyl methacrylate film (acrylic resin, manufactured by Mitsubishi Rayon, acrylprene, thickness 75 μm) as a transparent resin material was cut into a width of 30 mm × a width of 20 mm. An electrode 4 having a thickness of 10 μm was formed on this film by screen printing to obtain a second substrate 3. The electrode material used was ink mixed with carbon black in a binder.

As the first bonding step, the manufactured first substrate 2 and second substrate 3 are stacked, and in this state, the first substrate 2 and the second substrate 2 are heated by a hot plate heated to a press temperature of 82 ° C. using a hot press machine. The microchip 1 was manufactured by bonding the first substrate 2 and the second substrate 3 by sandwiching the substrate 3 and applying a pressure of 38 kgf / cm ² and holding it for 30 seconds.

  In this state, when the vicinity of the electrode of the microchip 1 was observed with a microscope, an unjoined portion was present in part.

  As the second bonding step, laser bonding was used to bond the vicinity of the electrodes. As the laser, an LD having a wavelength of 840 nm and an intensity of 20 W was used. When the electrode and its vicinity were scanned, the electrode portion generated heat and the resin in the vicinity of the electrode was dissolved to fill the gap.

  When the vicinity of the electrode of the microchip 1 was observed with a microscope after the second bonding step, the portion that was not bonded in the first bonding step was also completely bonded.

  In addition, a colored reagent was introduced from the through hole and observed for liquid leakage, but no liquid leakage occurred.

(Example 2)
Example 2 is an example in which the first substrate 2 and the second substrate 3 are both made of plate-like members with the microchip having the structure shown in FIG. First, the first substrate 2 in which the flow path 2b, the through hole 2a, and the liquid retaining grooves 22 and 23 are formed by injection molding, and the second substrate 3 in which the electrode 4 is formed are manufactured.

  Both the first and second substrates were produced by injection molding polymethyl methacrylate (acrylic resin, manufactured by Asahi Kasei, Delpet 70NH). The external dimensions are 30 mm wide × 20 mm wide × 1 mm thick, the flow path 2 b is 30 μm wide and 30 μm deep, the through hole 2 a is 2 mm in inner diameter, and the liquid retaining grooves 22 and 23 are separated from the flow path 2 b by 100 μm. And having a width of 100 μm and a depth of 30 μm. The electrode 4 was formed with the same dimensions and manufacturing method as in Example 1.

  After the surface modification by irradiating the excimer light on the bonding surface side of the first substrate 2 and the second substrate 3, cyanoacrylate-based adhesion is performed on the portions other than those surrounded by the liquid stop grooves 22 and 23 of the first substrate 2. The agent was applied, and the second substrate 3 was stacked thereon to perform bonding in the first bonding step.

  Subsequently, an infrared laser was used as the second bonding step, and laser scanning was performed on the bonding surface between the vicinity of the electrode, the flow path, and the liquid stop groove by setting the laser beam to be condensed on the bonding surface.

  The completed microchip was observed with a microscope and liquid leakage with a reagent, but there was no unbonded portion and no liquid leakage occurred.

1, 11, 21, 31 Microchip 2, 32 First substrate 2a, 32a, 32b Through hole 2b Channel 2c Depression 3, 33 Second substrate 2b Channel 4, 34, 35 Electrode G1 Gap G2 Unjoined portion 22, 23 Liquid stop groove

Claims (14)

A method of manufacturing a microchip with an electrode, which is manufactured by bonding two substrate members, and has at least a flow channel and an electrode connected to the flow channel on a bonding surface,
The flow path is formed on a surface that becomes one joining surface of the two substrate members, and the electrode is formed on the surface that becomes the one joining surface or the joining surface of the other substrate member. A substrate fabrication process for fabricating a single substrate member;
A first bonding step of bonding portions other than the vicinity of the electrodes of the two substrate members;
A second bonding step of bonding portions in the vicinity of the electrodes of the two substrate members;
The manufacturing method of the microchip with an electrode characterized by implementing.   2. The micro with electrode according to claim 1, wherein the first bonding step is performed by any one of thermal bonding, bonding with an adhesive, laser bonding, ultrasonic bonding, and bonding with an organic solvent. Chip manufacturing method.   The method for producing a microchip with electrodes according to claim 1 or 2, wherein the second bonding step is performed by any one of laser bonding, ultrasonic bonding, and bonding using an organic solvent.   4. The method for manufacturing a microchip with electrodes according to claim 1, wherein at least one of the substrate members is made of a resin. 5.   The method for producing a microchip with electrodes according to claim 4, wherein the resin-made substrate member is either a plate-like member or a film-like member.   6. The pretreatment step of performing surface modification by irradiating at least one of the bonding surfaces of the two substrate members with an energy beam subsequent to the substrate manufacturing step. The manufacturing method of the microchip with an electrode as described in one term.   The method for producing a microchip with electrodes according to claim 6, wherein the irradiation with the energy beam is at least one of excimer light, corona discharge, and plasma discharge. A method of manufacturing a microchip with an electrode, which is manufactured by bonding two substrate members, and has at least a flow channel and an electrode connected to the flow channel on a bonding surface,
A step of producing the two substrate members, including a step of forming a liquid stop groove at a position surrounding the flow path of the substrate member on which the flow path is formed or the opposite substrate member. A substrate manufacturing process;
A first bonding step of bonding the substrate member by applying an adhesive or an organic solvent to the outside of the liquid stop groove;
A second joining step for joining portions in the vicinity of the electrodes of the substrate member;
The manufacturing method of the microchip with an electrode characterized by performing by these.   9. The method for manufacturing a microchip with electrodes according to claim 8, wherein the second bonding step is performed by any one of laser bonding and ultrasonic bonding.   10. The method for manufacturing a microchip with electrodes according to claim 8, wherein at least one of the substrate members is made of a resin.   The method for producing a microchip with electrodes according to claim 10, wherein the resin-made substrate member is either a plate-like member or a film-like member.   12. The pretreatment step of performing surface modification by irradiating at least one of the bonding surfaces of the two substrate members with an energy ray subsequent to the substrate manufacturing step. The manufacturing method of the microchip with an electrode as described in one term.   The method of manufacturing a microchip with electrodes according to claim 12, wherein the irradiation with the energy beam is at least one of excimer light, corona discharge, and plasma discharge.   A microchip with an electrode, which is manufactured by the manufacturing method according to claim 1.

Images