JP2009136820A - Fluid element and method of manufacturing laminated structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid element of which the fluid in a flow channel can be visually confirmable from the outside, and to provide a method of manufacturing a laminated structure. <P>SOLUTION: A microreactor 1 (a kind of fluid element) is formed by sequentially joining a plurality of conductive films 12A-12D formed by electrocasting method at the normal temperature with respect to a glass substrate 10 to be provided as a second substrate. The glass substrate 10 and the conductive film 12A are joined at the normal temperature through a Cr film 11 to be provided at the glass substrate 10 as a joining film, and a flow channel 121 formed on the conductive film 12A is made to be visually confirmable from the upper surface 10a side of the glass substrate 10. The conductive film 12A-12D respectively have flow channel patterns in forms of holes, grooves and the like for passing the fluid, and by being laminated, they are constituted to form three-dimensional flow channels joined in the laminated body from the inlet to the outlet. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fluidic device and a method for manufacturing a laminated structure.

  2. Description of the Related Art In recent years, additive manufacturing methods have rapidly spread as a method for forming a complex three-dimensional object designed by a computer in a short period of time in parts manufacture. This additive manufacturing method has often been applied to relatively large parts having a size of several centimeters or more. However, in recent years, microstructures formed by precision processing, such as micro gears and micro optical parts, are used. This method is also applied to microfluidic devices and the like.

  A microfluidic device is a device also called a microfluidic device, a microfluidic device, a microfabricated device, a love-on-chip, or a micro total analysis system (μ-TAS). The microfluidic device can be integrated with a microfluidic device having other functions such as synthesis, physicochemical processing, and detection to construct a microchemical system. The microfluidic device has excellent uniformity of reaction solution temperature, good temperature followability, can shorten the reaction time, requires a small amount of sample, can reduce the amount of solvent used, etc. It has features such as fewer resources and energy, energy saving operation, and reduced waste, and future development is expected.

  A microreactor, a kind of microfluidic device, is a device having a small reaction field several orders of magnitude smaller than that of a normal reaction device. Also called a reactor. Such a microreactor has a large device surface area per unit volume, and is considered to be capable of precise temperature control by reducing heat capacity, is sensitive to temperature, and for catalytic reactions where the reaction rate is dominant in the contact area, As a particularly attractive device, research is being carried out in each country (for example, see Patent Document 1).

In addition, as a microfluidic device manufacturing method, for example, a release layer made of polyimide or a thermal oxide film and a conductive layer are sequentially formed on a Si wafer substrate, and a resist pattern layer that is an inverted pattern of a cross-sectional pattern is formed on the conductive layer. In the space of the resist pattern layer, a cross-sectional pattern member is formed by plating, and further, the resist pattern layer is removed to prepare a donor substrate. The target substrate is disposed opposite to the donor substrate. A method of manufacturing a laminated structure by transferring and laminating a cross-sectional pattern member to a target substrate by repeating a separation process after positioning and press-contacting the cross-sectional pattern member (for example, Patent Document 2). reference.).
JP 2006-187684 A JP 2004-358602 A

  The objective of this invention is providing the manufacturing method of the fluid element and laminated structure which can visually recognize the fluid in a flow path from the outside.

  In order to achieve the above object, one embodiment of the present invention provides the following fluidic device and method for manufacturing a laminated structure.

(1) The structure in which the flow path pattern constituting the flow path is formed, and the structure is joined so that at least a part of the flow path pattern exposed on a predetermined surface of the structure is provided in a visible state And a fluidic device.

(2) The fluid element according to (1), wherein the structure is formed by stacking a plurality of conductive films formed by an electroforming method.

(3) The fluid element according to (1), wherein the substrate is formed of a transparent material and bonded to the structure through a bonding film.

(4) The fluid element according to (2), wherein the conductive film is bonded by directly contacting the cleaned bonding surface.

(5) The fluid element according to (3), wherein the transparent material is glass and is bonded to the structure via the transparent bonding film.

(6) A step of forming a plurality of thin films having a flow path pattern corresponding to the flow path shape on the first substrate, and the thin films are sequentially transferred and laminated on the transparent second substrate through the bonding film. The manufacturing method of a laminated structure including the process and the process of processing the said bonding film so that the said flow-path pattern formed in the said thin film can permeate | transmit and visually recognize a said 2nd board | substrate.

(7) forming a plurality of thin films having a flow path pattern corresponding to the flow path shape on the first substrate, and sequentially transferring the thin films to the transparent second substrate through the transparent bonding film A method of manufacturing a laminated structure including a step of laminating.

(8) Lamination including a step of forming a plurality of thin films having a flow path pattern corresponding to a flow path shape on the first substrate, and a step of sequentially transferring and laminating the thin films on a transparent second substrate Manufacturing method of structure.

(9) The method for manufacturing a laminated structure according to (6), wherein the treatment is performed by removing the bonding film corresponding to the flow path pattern by etching.

(10) The method for manufacturing a laminated structure according to (6), wherein the treatment is performed by making the bonding film transparent by anodizing treatment.

(11) The method for manufacturing a laminated structure according to any one of (6) to (8), wherein the thin film is formed by forming a conductive film by an electroforming method.

(12) The method for manufacturing a laminated structure according to any one of (6) to (8), wherein the bonding of the thin film is performed by directly contacting a cleaned bonding surface.

  According to the fluid element of the first aspect, the fluid in the flow path can be visually recognized from the outside.

  According to the fluid element of the second aspect, the structure having the flow path can be efficiently formed with high accuracy.

  According to the fluid element of the third aspect, it is possible to join the structure that cannot be directly joined to the transparent substrate.

  According to the fluid element of the fourth aspect, sufficient bonding strength can be obtained without requiring a troublesome bonding process.

  According to the fluid element of the fifth aspect, the transparent glass can be bonded to the structure with a sufficient bonding strength.

  According to the manufacturing method of the laminated structure of Claim 6, the fluid in a flow path can be visually recognized from the outside.

  According to the manufacturing method of the laminated structure of Claim 7, the fluid in a flow path can be visually recognized from the outside.

  According to the method for manufacturing a laminated structure according to claim 8, the fluid in the flow path can be visually recognized from the outside.

  According to the method for manufacturing a laminated structure according to the ninth aspect, the fluid in the flow path can be visually recognized from the outside while ensuring the bonding strength by the bonding film.

  According to the method for manufacturing a laminated structure according to claim 10, the fluid in the flow path can be visually recognized from the outside while ensuring the bonding strength by the bonding film.

  According to the method for manufacturing a laminated structure according to claim 11, a plurality of conductive films constituting the laminated structure can be efficiently formed with high accuracy.

  According to the method for manufacturing a laminated structure according to the twelfth aspect, sufficient bonding strength can be obtained without requiring a troublesome bonding process.

[First embodiment]
FIG. 1 is a perspective view showing a microreactor as a fluidic device according to a first embodiment of the present invention.

  The microreactor 1 is formed by sequentially bonding a plurality of conductive films 12A to 12D formed by electroforming to a glass substrate 10 provided as a second substrate at room temperature. The glass substrate 10 and the conductive film 12A are bonded to the glass substrate 10 via a Cr film 11 provided as a bonding film, and the flow path 121 formed in the conductive film 12A is visible from the upper surface 10a side of the glass substrate 10. It can be done. The conductive films 12 </ b> A to 12 </ b> D each have a flow path pattern such as a hole and a groove for allowing fluid to pass therethrough, and are three-dimensionally connected to each other from the fluid inlet to the outlet by being laminated. It is comprised so that the laminated structure which has an appropriate flow path may be formed.

  Here, “normal temperature bonding” means that the surfaces to be bonded are irradiated with a neutral atom beam, an ion beam or the like to clean the surfaces, and then the cleaned bonding surfaces are in a normal temperature (for example, 15 to 25 ° C.) atmosphere. This is a bonding method in which atoms directly contact each other and atoms are directly bonded to each other, and is also referred to as surface activated bonding. By bonding the thin film by room temperature bonding, the microreactor 1 is obtained as a highly accurate laminated structure with little change in the shape and thickness of the thin film. It should be noted that no load may be applied at the time of joining. In addition to room temperature bonding, the cleaned bonding surfaces may be bonded by heating at a predetermined temperature (for example, 100 ° C. or lower).

  FIG. 2 is an exploded perspective view of the microreactor according to the first embodiment of the present invention. In addition, about the size of each part, it is different from an actual dimension on account of description.

  The glass substrate 10 is made of a colorless and transparent glass material, and the upper surface 10a is formed as a smooth surface. Further, the lower surface, which is the surface opposite to the upper surface 10a, has a Cr film 11 formed with a thickness of 50 nm by a film forming method such as a sputtering method. The Cr film 11 is a bonding film that provides bonding between glass and a conductive film, and is not limited to the above-described thickness as long as sufficient bonding is obtained, and may be a thinner film. Moreover, you may form with other metal materials, such as Ti.

  The conductive films 12A to 12D are made of Ni and are formed with a thickness of 50 μm by electroforming. Note that a thin film of Au (not shown) is provided on the upper surfaces 12a of the conductive films 12A to 12D by sputtering to enhance the bonding between the conductive films, but is not shown. The conductive film 12 </ b> A is a reaction layer, and includes two through holes 120 and a flow path 121 formed in a rectangular flow path pattern. The flow path 121 is connected to the two through holes 120. The channel 121 can be formed with a width of 10 to 500 μm, but in this embodiment, the channel 121 is formed with a width of 100 μm.

  The conductive film 12B is a through layer and has two through holes 120.

  The conductive film 12 </ b> C is a mixed layer, and includes four through holes 120 and a flow path 122 connected to the three through holes 120. The flow path 122 is formed with a width of 100 μm.

  The conductive film 12D is an inlet / outlet layer, and has two inlets 123A and 123B for supplying fluid and one outlet 124 for discharging fluid.

  3A and 3B show a donor substrate having a conductive film constituting the microreactor according to the first embodiment of the present invention. FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along a line BB in FIG. It is sectional drawing shown.

  The donor substrate 15 is made of a stainless steel substrate having a predetermined surface roughness as a first substrate, and has a plurality of conductive films 12A to 12D constituting a microreactor on an upper surface 15a. The conductive films 12 </ b> A to 12 </ b> D are formed in, for example, a square shape of 1 cm square, and are arranged in a single line or a two-dimensional array according to the order of lamination in order to improve workability in the transfer process. In this embodiment, the conductive film 12A, the conductive film 12B, the conductive film 12C, and the conductive film 12D are stacked in this order over the glass substrate.

(Formation of donor substrate)
In the present embodiment, donor substrate 15 is formed using an electroforming method. First, a stainless steel substrate is prepared. Next, a dry film resist having a thickness of 30 to 50 μm is formed on the donor substrate 15, and after exposure with a photomask corresponding to the shape of each conductive film, the dry film resist is developed. As a result, a resist pattern in which positive / negative is inverted corresponding to the shape of each conductive film is formed. Next, the donor substrate 15 having this resist pattern is immersed in a plating tank, and a Ni electroformed film is grown on the surface of the donor substrate 15 not covered with the resist pattern. The film thickness of the electroformed film is made smaller than the film thickness of the dry film resist. Next, Au is formed on the resist pattern and Ni by sputtering. Next, by removing the resist pattern, the donor substrate 15 provided with the conductive films 12A to 12D on the upper surface 15a is obtained. In addition, the donor substrate 15 can use the insulating substrate which consists of insulators, such as Si, a ceramic, a synthetic resin other than the above-mentioned stainless steel substrate, for example.

  In the case of using an insulating substrate, first, polyimide is applied to the surface of the substrate with a thickness of 1 to 5 μm by spin coating, and a release layer is formed by performing curing treatment and surface fluorination treatment. Next, in order to impart electrical conductivity to the surface of the release layer, a conductive film made of a metal such as Ti or Cu is provided.

(Lamination of conductive film)
4A to 4C are diagrams schematically showing a conductive film laminating process. Hereinafter, the lamination of conductive films will be described with reference to FIGS. 1 to 3 together. In addition, since several electrically conductive film 12A-12D corresponding to each cross-sectional shape of the microreactor 1 is sequentially transcribe | transferred on the glass substrate 10 through the same lamination process in the lamination | stacking apparatus 20, the electrically conductive film 12A-12D shown in FIG. Of these, only the step of laminating the conductive films 12A and 12B will be described. Therefore, illustration of the conductive film 12D is omitted in FIG.

  In manufacturing the microreactor 1, first, as shown in FIG. 4A, the donor substrate 15 is placed on the lower stage 25 in the vacuum chamber 21, and the glass substrate 10 is adsorbed on the upper stage 26 in the vacuum chamber 21. Fix by etc. A Cr film 11 is provided on the bonding surface of the glass substrate 10.

  Next, the inside of the vacuum chamber 21 is evacuated from the exhaust port 22 to be in a high vacuum state or an ultrahigh vacuum state. Next, the lower stage 25 is moved relative to the upper stage 26, and the conductive film 12A of the donor substrate 15 is positioned immediately below the glass substrate 10. Next, the bonding surface is cleaned by irradiating the surface of the Cr film 11 provided on the glass substrate 10 with an argon atom beam from a FAB (Fast Atom Bombardment) source 24A. Similarly, the bonding surface is cleaned by irradiating the surface of the conductive film 12A with an argon atom beam from the FAB source 24B.

  Next, as shown in FIG. 4B, the vertical stage 28 is lowered, the glass substrate 10 and the donor substrate 15 are pressed with a predetermined load for a predetermined time, and the glass substrate 10, the conductive film 12A, and the Cr film are pressed. 11 is bonded at room temperature.

  Next, as shown in FIG. 4C, when the vertical stage 28 is raised, the conductive film 12A is peeled from the donor substrate 15 and transferred to the glass substrate 10 side. This is because the bonding force between the conductive film 12 </ b> A and the Cr film 11 is greater than the adhesion force between the conductive film 12 </ b> A and the donor substrate 15.

  Next, the lower stage 25 is moved and positioned so that the conductive film 12B on the donor substrate 15 is disposed immediately below the glass substrate 10. Next, the bonding surface is cleaned by irradiating the surface of the conductive film 12A transferred to the glass substrate 10 side (the surface in contact with the donor substrate 15) and the surface of the conductive film 12B with an argon atom beam. .

  Next, when the vertical stage 28 is lowered and the conductive film 12A and the conductive film 12B are joined at room temperature, and then the vertical stage 28 is raised, the conductive film 12B is peeled from the donor substrate 15 and transferred to the glass substrate 10 side. Is done.

  Thereafter, the same process is repeated, and after the joining of the conductive films 12A to 12D is completed, the microreactor 1 is formed by removing the glass substrate 10 from the upper stage 28. By thus joining and laminating the conductive films 12A to 12D by room temperature bonding, changes in the shape and thickness of the conductive films 12A to 12D are reduced.

  5A and 5B are partial perspective views showing the etching of the Cr film, where FIG. 5A is a view before etching and FIG. 5B is a view after etching.

  By removing the Cr film 11 provided between the glass substrate 10 and the conductive film 12A partially from the microreactor 1 formed as described above, the state of the fluid supplied into the microreactor 1 can be changed to the outside. Can be visually recognized.

  First, an etchant for removing the Cr film 11 is supplied from the inlets 123A and 123B of the microreactor 1 described with reference to FIG. In the state before etching, as shown in FIG. 5A, the flow path 121 cannot be visually recognized by the Cr film 11 between the glass substrate 10 and the conductive film 12A. However, when the etchant flows into the back surface of the glass substrate 10 through the through-hole 120 and the channels 121 and 122 in the microreactor 1, as shown in FIG. The film 11 is etched and the flow path 121 becomes visible.

(Operation of microreactor)
Below, the operation | movement which supplies and mixes two liquids to the microreactor 1 is demonstrated.

  First, liquids having different liquidity are simultaneously supplied from the lower surface side of the conductive film 12D shown in FIG. 2 to the inlets 123A and 123B. Here, the first liquid L1 is supplied from the inlet 123A, and the second liquid L2 is supplied from the inlet 123B.

  The first liquid L1 and the second liquid L2 are introduced into the mixed layer of the conductive film 12C, mixed in the flow path 122, and integrated, and supplied from the through hole 120 to the conductive film 12B.

  The mixed liquid is guided to the upper layer through the through layer of the conductive film 12B, and is supplied from the through hole 120 to the conductive film 12A.

  The liquid supplied to the conductive film 12A is introduced into the flow channel 121 from the through hole 120, and the diffusion mixing is promoted by moving in the flow channel that is folded back into a rectangular shape. The observer can observe the state of the liquid moving in the flow path 121 from the upper surface 10a side of the glass substrate 10.

  The liquid L sent out from the flow path 121 to the through hole 120 is discharged as the liquid L3 from the outlet 124 of the conductive film 12D through the through holes 120 of the conductive films 12B and 12C.

[Second Embodiment]
FIG. 6 is a perspective view showing a microreactor as a fluid element according to a second embodiment of the present invention. In the following description, parts having the same configurations and functions as those of the first embodiment are denoted by the same reference numerals.

  The microreactor 1 is different from the first embodiment in that an Al film 31 is provided as a bonding film for bonding the glass substrate 10 and the conductive film 12A. Further, the Al film 31 is an anodized portion 31A in which a portion where the flow path is provided is changed to a transparent film based on the anodizing process.

  FIG. 7 is a partial perspective view showing the process for the Al film, where (a) is before the process and (b) is after the process.

The Al film 31 is formed by supplying an electrolytic solution such as oxalic acid or phosphoric acid into the flow channel after the microreactor 1 is formed, and electrolyzing the Al film 31 as an anode in a state where the flow channel is filled with the electrolytic solution. The Al surface exposed in the channel 121 changes to a transparent anodized portion 31A made of Al ₂ O ₃ . As shown in FIG. 7 (a), even if the lower layer flow path is invisible from the glass substrate 10 immediately after the formation of the microreactor 1, the anodic oxidation treatment is performed to form the flow path 121 as shown in FIG. 7 (b). The portion 121 in contact with the surface is oxidized and changed to the anodic oxidation portion 31 </ b> A, whereby the flow path 121 becomes visible from the glass substrate 10 side.

[Third embodiment]
FIG. 8 is a perspective view showing a microreactor as a fluidic device according to a third embodiment of the present invention.

  In the microreactor 1, a SiN film 41 is provided as a bonding film for bonding the glass substrate 10 and the conductive film 12A. Although not shown, an Al thin film is formed by sputtering on the surfaces of the conductive films 12A to 12D. It is different from the first embodiment in that it is provided.

Since the SiN film 41 is transparent and has bondability with Al, the flow path 121 can be viewed from the upper surface 10a side of the glass substrate 10 by bonding with the conductive film 12A. In place of the SiN film, an Al ₂ O ₃ film may be provided on the surface of the glass substrate 10 in advance.

[Fourth embodiment]
FIG. 9 is a perspective view showing a microreactor as a fluidic device according to a fourth embodiment of the present invention.

  This microreactor 1 is the second point in that a transparent resin substrate 50 made of a transparent resin such as polymethyl methacrylate or polycarbonate is used instead of the glass substrate 10 as a target substrate in the microreactor 1 of the second embodiment. This is different from the embodiment.

  In the formation of the microreactor 1 by room temperature bonding, even a resin material having a thermal restriction can be bonded with a high bonding strength equivalent to the case of using glass by coating with a conductive film such as an Al film. Moreover, it is possible to realize a configuration in which the flow path can be visually recognized from the upper surface 50a as in the case of the glass substrate, and it is possible to reduce changes in shape and thickness.

[Fifth embodiment]
FIG. 10 is a perspective view showing a microreactor as a fluidic device according to a fifth embodiment of the present invention.

  The microreactor 1 is provided with a sapphire substrate 60 instead of the glass substrate 10 as a target substrate in the microreactor 1 of the first embodiment, and a conductive film 12A in which an Al thin film is provided on the surface instead of Au. The second embodiment is different from the first embodiment in that the bonding film is not required.

  Since the sapphire substrate 60 is transparent and thermally stable, it is possible to realize a configuration in which the flow path can be visually recognized from the upper surface 60a similarly to the glass substrate, and at the same high bonding strength as when glass is used. Can be joined. Moreover, it is excellent in workability and workability in a process using a semiconductor process. In place of the sapphire substrate, a substrate made of zinc oxide or strontium titanate may be used.

[Other embodiments]
The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention. In addition, the constituent elements of the respective embodiments can be arbitrarily combined without departing from the spirit of the present invention.

  For example, it is needless to say that the shape of the microreactor, the number of conductive films, the thickness, and the like are not limited thereto. Further, the thin film constituting the microreactor is not limited to the above-described conductive film such as Ni, and may be a thin film made of ceramics or the like.

  Regarding the electroconductive film formed by electroforming, one having a thickness of 10 to 100 μm, particularly 20 to 50 μm, is often used, but one having a thickness of 500 μm or more can also be formed.

FIG. 1 is a perspective view showing a microreactor as a fluidic device according to a first embodiment of the present invention. FIG. 2 is an exploded perspective view of the microreactor according to the first embodiment of the present invention. 3A and 3B show a donor substrate having a conductive film constituting the microreactor according to the first embodiment of the present invention. FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along a line BB in FIG. It is sectional drawing shown. 4A to 4C are diagrams schematically showing a conductive film laminating process. 5A and 5B are partial perspective views showing the etching of the Cr film, where FIG. 5A is a view before etching and FIG. 5B is a view after etching. FIG. 6 is a perspective view showing a microreactor as a fluid element according to a second embodiment of the present invention. FIG. 7 is a partial perspective view showing the process for the Al film, where (a) is before the process and (b) is after the process. FIG. 8 is a perspective view showing a microreactor as a fluidic device according to a third embodiment of the present invention. FIG. 9 is a perspective view showing a microreactor as a fluidic device according to a fourth embodiment of the present invention. FIG. 10 is a perspective view showing a microreactor as a fluidic device according to a fifth embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Microreactor 10 ... Glass substrate 10a ... Upper surface 11 ... Cr film 12A ... Conductive film 12a ... Upper surface 12A-12D ... Conductive film 15 ... Donor substrate 15a ... Upper surface 20 ... Laminating apparatus 21 ... Vacuum chamber 22 ... Exhaust port 24A, 24B ... FAB source 25 ... lower stage 26 ... upper stage 28 ... vertical stage 31 ... Al film 31A ... anodized portion 41 ... SiN film 50 ... transparent resin substrate 50a ... upper surface 60 ... sapphire substrate 60a ... upper surface 120 ... through hole 121, 122 ... Channel 123A, 123B ... Inlet 124 ... Outlet

Claims (12)

A structure in which a flow path pattern constituting the flow path is formed;
A fluid element comprising: a substrate bonded to the structure so that at least a part of the flow path pattern exposed on a predetermined surface of the structure is provided in a visible state.   The fluid element according to claim 1, wherein the structure is formed by laminating a plurality of conductive films formed by an electroforming method.   The fluid element according to claim 1, wherein the substrate is formed of a transparent material and bonded to the structure via a bonding film.   The fluid element according to claim 2, wherein the conductive film is bonded by directly contacting the cleaned bonding surface.   The fluid element according to claim 3, wherein the transparent material is glass and is bonded to the structure via the transparent bonding film. Forming a plurality of thin films having a flow path pattern corresponding to the flow path shape on the first substrate;
Sequentially transferring and laminating the thin film to a transparent second substrate through a bonding film;
And a step of processing the bonding film so that the flow path pattern formed in the thin film can be seen through the second substrate. Forming a plurality of thin films having a flow path pattern corresponding to the flow path shape on the first substrate;
And a step of sequentially transferring and laminating the thin film onto a transparent second substrate through a transparent bonding film. Forming a plurality of thin films having a flow path pattern corresponding to the flow path shape on the first substrate;
And a step of sequentially transferring and laminating the thin film onto a transparent second substrate.   The method for manufacturing a laminated structure according to claim 6, wherein the treatment is performed by removing the bonding film corresponding to the flow path pattern by etching.   The method for manufacturing a laminated structure according to claim 6, wherein the treatment is performed by making the bonding film transparent by anodizing treatment.   The method for producing a laminated structure according to any one of claims 6 to 8, wherein the thin film is formed by forming a conductive film by an electroforming method.   The method for manufacturing a laminated structure according to any one of claims 6 to 8, wherein the thin film is bonded by directly contacting the cleaned bonding surface.

Images