CN109205551B - Tapered array flexible electrode and preparation method thereof - Google Patents
Tapered array flexible electrode and preparation method thereof Download PDFInfo
- Publication number
- CN109205551B CN109205551B CN201811297992.3A CN201811297992A CN109205551B CN 109205551 B CN109205551 B CN 109205551B CN 201811297992 A CN201811297992 A CN 201811297992A CN 109205551 B CN109205551 B CN 109205551B
- Authority
- CN
- China
- Prior art keywords
- micro
- flexible
- polymer substrate
- nano
- flexible polymer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B7/00—Microstructural systems; Auxiliary parts of microstructural devices or systems
- B81B7/04—Networks or arrays of similar microstructural devices
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B3/00—Devices comprising flexible or deformable elements, e.g. comprising elastic tongues or membranes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
- B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
- B81C1/00015—Manufacture or treatment of devices or systems in or on a substrate for manufacturing microsystems
- B81C1/00134—Manufacture or treatment of devices or systems in or on a substrate for manufacturing microsystems comprising flexible or deformable structures
- B81C1/00166—Electrodes
Abstract
The invention provides a conical array flexible electrode which comprises a flexible polymer substrate and a metal conducting layer, wherein the surface of one side of the flexible polymer substrate is provided with a micro-nano conical array structure, and the outer peripheral surface of the micro-nano conical array structure is a rough surface; the metal conducting layer completely covers the peripheral surface of the micro-nano cone and completely covers an area, not provided with the micro-nano cone, on the surface of one side of the flexible polymer substrate. The flexible polymer substrate of the flexible electrode has good adhesion with the metal conducting layer, the structure is stable, the electrode impedance is low, and the electrochemical performance is excellent. The flexible electrode can be well applied to flexible electronic skins and implanted electrodes. The invention also provides a preparation method of the tapered array flexible electrode.
Description
Technical Field
The invention relates to the technical field of biomedical engineering, in particular to a conical array flexible electrode and a preparation method thereof.
Background
The flexible microelectrode helps a patient to perform functional reconstruction by applying pulse type current stimulation to specific nervous tissues, and is widely applied to medical instruments such as artificial cochlea, artificial retina and the like. The adhesion between the substrate and the conducting layer in the flexible microelectrode and the low impedance of the interface between the flexible microelectrode and nerve cells play an important role in ensuring that the flexible microelectrode has stable and reliable long-term electrical stimulation/signal recording.
In the traditional electrode processing method, the problem of wire breakage or falling off of the conducting layer is easily caused due to poor adhesion between the metal of the conducting layer and the substrate, so that the stimulation efficiency of the electrode is greatly influenced; in addition, the flexible microelectrode shows higher impedance due to smaller surface area, and the impedance is further increased by reactive colloid wrapping which occurs at the interface of the flexible microelectrode and nerve cells in the long-term implantation process. Therefore, in order to solve the above problems, it is necessary to invent a new construction technology which can increase the adhesion between the substrate and the interface, increase the specific surface area of the flexible microelectrode, obtain an optimized low impedance interface, and avoid the possible damage of the electrode material to the nerve tissue, thereby ensuring good contact and function realization of the recording or stimulating electrode and the nerve tissue.
Disclosure of Invention
In view of this, the embodiment of the present invention provides a tapered array flexible electrode, which has good adhesion between a flexible polymer substrate and a metal conductive layer, a stable structure, low electrode impedance, and excellent electrochemical performance.
Specifically, a first aspect of the embodiments of the present invention provides a tapered array flexible electrode, including:
the flexible polymer substrate is provided with a micro-nano conical array structure on one side surface, wherein the outer peripheral surface of the micro-nano conical array structure is a rough surface;
the metal conducting layer completely covers the peripheral surface of the micro-nano cone and completely covers an area, not provided with the micro-nano cone, on the surface of one side of the flexible polymer substrate.
The outer peripheral surface of the micro-nano cone is provided with a plurality of concave structures extending longitudinally to form the rough surface. Specifically, the recessed structures are nano-sized, and a plurality of recessed structures, which may be grooves, are uniformly arranged on the tapered outer circumferential surface. The existence of the concave structure increases the roughness of the micro-nano conical peripheral surface, thereby being beneficial to the combination of the metal conducting layer on the flexible polymer substrate.
Optionally, the diameter of the bottom of the micro-nano cone is 200nm-80 μm. Further, the diameter of the bottom of the taper is 200nm to 1 μm, and further, the diameter of the bottom of the taper is 200nm to 800nm, 200nm to 500 nm. Further, the diameter of the bottom of the taper is 1 μm to 80 μm, and further, the diameter of the bottom of the taper is 1 μm to 10 μm, 15 μm to 60 μm.
Optionally, the height of the micro-nano cone is 200nm to 80 μm. Further, the height of the taper is 200nm to 1 μm. Further, the height of the taper is 300nm to 800nm, 500nm to 700 nm. Further, the height of the taper is 1 μm to 80 μm, and further, the height of the taper is 1 μm to 10 μm, 15 μm to 60 μm.
Optionally, the period of the micro-nano tapered array structure is 200nm-80 μm. The taper pitch is the difference between the diameter size of the colloidal crystal used and the diameter of the bottom of the taper. Specifically, the taper pitch may be specifically set according to the size of the taper.
In the invention, the micro-nano tapered array structure is a part of the flexible polymer substrate, namely the flexible polymer substrate and the micro-nano tapered array structure are in an integral structure.
Optionally, the material of the flexible polymer substrate includes at least one of polyimide, polydimethylsiloxane, polyethylene terephthalate, parylene, and photoresist. The photoresist can be positive photoresist or negative photoresist, and particularly can be but is not limited to SU8 photoresist and AZ photoresist.
Optionally, the thickness of the metal conductive layer is 50nm-300 nm. Further, the thickness of the metal conducting layer is 100nm-200 nm.
Optionally, the material of the metal conductive layer includes at least one of platinum (Pt), gold (Au), platinum-iridium alloy (Pt-Ir), titanium nitride (TixNy), iridium oxide (IrOx), and Indium Tin Oxide (ITO).
The metal conducting layer also has a micro-nano tapered array morphology consistent with the morphology of the flexible polymer substrate.
According to the conical array flexible electrode provided by the first aspect of the invention, the surface of the flexible polymer substrate is provided with the micro-nano conical array structure, and the surface of the conical structure is rough, so that the flexible polymer substrate and the metal conducting layer can be better adhered together, and the structural stability of the electrode is improved; when the electrode is implanted into a living body, the effective contact area between the electrode and a tissue interface can be greatly increased by the conical structure on the surface of the electrode, so that the impedance is reduced, and the electrochemical performance of the electrode is remarkably improved.
Accordingly, in a second aspect, the present invention provides a method for preparing a tapered array flexible electrode, comprising the following steps:
providing a flexible polymer substrate and performing a hydrophilization treatment;
assembling a layer of colloidal crystals on the surface of the flexible polymer substrate subjected to hydrophilization treatment;
etching the flexible polymer substrate by using the colloidal crystal as a template and adopting a plasma etching method to obtain the flexible polymer substrate with a micro-nano conical array structure formed on one side surface, wherein the outer peripheral surface of the micro-nano conical structure is a rough surface;
and depositing a metal conducting layer on the flexible polymer substrate, wherein the metal conducting layer completely covers the peripheral surface of the micro-nano cone and completely covers an area, not provided with the micro-nano cone, on the surface of one side of the flexible polymer substrate.
Wherein the flexible polymer substrate may be at least one of polyimide, polydimethylsiloxane, polyethylene terephthalate, parylene, photoresist. The flexible polymer substrate can be a single polymer substrate, or a polymer material can be formed on another substrate by spin coating or film casting. The further substrate may be a silicon wafer.
Wherein the hydrophilization treatment comprises the following specific operations: and (3) treating the flexible polymer substrate for 2-5min by using a plasma cleaning machine to enable the surface of the flexible polymer substrate to have hydrophilic property.
The colloidal crystal can be at least one of polymethyl methacrylate microspheres, polystyrene microspheres and silicon dioxide microspheres, the diameter of the colloidal crystal is larger than or equal to the diameter of the bottom of a micro-nano cone in a pre-prepared micro-nano cone array structure, and the diameter can be 200nm-80 μm.
The assembly method of the colloidal crystal is selected from at least one of the following assembly methods: a drop coating method, a spin coating method, a vertical sedimentation method, an interface assembly method.
In the invention, the size of the conical structure can be regulated and controlled by selecting colloidal crystals with different sizes. Wherein, the nanometer conical array can adopt nanometer size or micron size colloidal crystal as template; the micron conical array adopts micron-sized colloidal crystals as templates, and the diameter of the bottom of the obtained conical structure is smaller than that of the colloidal crystals or close to that of the colloidal crystals.
In the plasma etching process, the size of the colloidal crystal is gradually reduced so that the polymer base material below the colloidal crystal is exposed and etched, the more the size of the colloidal crystal is reduced, the more the exposed polymer base material is, until the colloidal crystal is completely etched, the micro-nano tapered morphology is obtained, and the etching process enables the outer peripheral surface of the tapered structure to form a rough surface. Specifically, optionally, the micro-nano tapered outer circumferential surface has a plurality of longitudinally extending concave structures to form the rough surface.
Optionally, the diameter of the bottom of the micro-nano cone is 200nm-80 μm. Further, the diameter of the bottom of the taper is 200nm to 1 μm, and further, the diameter of the bottom of the taper is 200nm to 800nm, 200nm to 500 nm. Further, the diameter of the bottom of the taper is 1 μm to 80 μm, and further, the diameter of the bottom of the taper is 1 μm to 10 μm, 15 μm to 60 μm.
Optionally, the height of the micro-nano cone is 200nm to 80 μm. Further, the height of the taper is 200nm to 1 μm. Further, the height of the taper is 300nm to 800nm, 500nm to 700 nm. Further, the height of the taper is 1 μm to 80 μm, and further, the height of the taper is 1 μm to 10 μm, 15 μm to 60 μm.
Optionally, the taper pitch of the micro-nano tapered array structure is a difference between a diameter size of the used colloidal crystal and a diameter of the bottom of the taper. Specifically, the taper pitch may be specifically set according to the size of the taper.
In the invention, the diameter, height and spacing of the bottom of the obtained cone can be regulated and controlled by adjusting parameters in the etching process, such as gas used for reaction, gas flow, gas pressure, etching time, etching power and the like.
The metal conducting layer can be prepared by adopting a magnetron sputtering or electron beam evaporation coating mode. After the metal conducting layer is covered, the surface of the electrode still keeps the shape of a micro-nano tapered array.
Optionally, the thickness of the metal conductive layer is 50nm-300 nm. Further, the thickness of the metal conducting layer is 100nm-200 nm.
Optionally, the material of the metal conductive layer includes at least one of platinum (Pt), gold (Au), platinum-iridium alloy (Pt-Ir), titanium nitride (TixNy), iridium oxide (IrOx), and Indium Tin Oxide (ITO).
In the invention, the thickness of the deposited metal conducting layer can be regulated and controlled by adjusting parameters of the deposition process, such as deposition time, deposition current and the like.
The preparation method of the tapered array flexible electrode provided by the second aspect of the invention has the advantages of simple process, low cost, high efficiency, fast self-assembly process and controllable shape and size of the tapered array. The flexible electrode prepared by the method has the advantages that the conical shape formed by the substrate has certain roughness, so that the problem of poor adhesion between the substrate and the metal conductive layer can be obviously solved, the phenomenon of delamination is avoided, and the structural stability and the use reliability of the electrode are improved.
The invention also provides an implantable electrode comprising a tapered array of flexible electrodes according to the first aspect of the invention. In the implanted electrode, the adhesion between the substrate of the conical array flexible electrode and the interface is strong, the specific surface area of the electrode is high, and the impedance interface is low, so that the implanted electrode has excellent electrochemical performance; meanwhile, the possible damage of electrode materials to nerve tissues can be avoided, so that good contact and function realization of the recording or stimulating electrode and the nerve tissues are ensured.
The invention also provides a flexible electronic skin comprising a tapered array of flexible electrodes according to the first aspect of the invention. The flexible electronic skin has excellent flexibility and electrochemical performance.
Advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of the invention.
Drawings
FIG. 1 is a schematic diagram of a process for preparing a tapered array flexible electrode in example 1 of the present invention;
FIGS. 2a and 2b are an electron microscope image of a nano-tapered array structure on the surface of a flexible polymer substrate prepared in example 1 of the present invention and an electron microscope image of a tapered array flexible electrode, respectively;
FIGS. 3a and 3b are respectively an electron microscope image of a nano-tapered array structure on the surface of a flexible polymer substrate prepared in example 2 of the present invention and an electron microscope image of a tapered array flexible electrode;
FIGS. 4a and 4b are respectively an electron microscope image of a nano-tapered array structure on the surface of a flexible polymer substrate prepared in example 3 of the present invention and an electron microscope image of a tapered array flexible electrode;
FIG. 5 is a schematic diagram of the process for preparing the tapered array flexible electrode in example 4 of the present invention;
FIGS. 6a and 6b are respectively an electron microscope image of a micro tapered array structure on the surface of a flexible polymer substrate prepared in example 4 of the present invention and an electron microscope image of a tapered array flexible electrode;
FIGS. 7a and 7b are respectively an electron microscope image of a micro tapered array structure on the surface of a flexible polymer substrate prepared in example 5 of the present invention and an electron microscope image of a tapered array flexible electrode;
fig. 8 is a schematic structural diagram of an implantable electrode according to embodiment 10 of the present invention.
Detailed Description
While the following is a description of the preferred embodiments of the present invention, it should be noted that those skilled in the art can make various modifications and improvements without departing from the principle of the embodiments of the present invention, and such modifications and improvements are considered to be within the scope of the embodiments of the present invention.
Example 1
A tapered array flexible electrode includes a flexible polymer substrate and a metallic conductive layer attached to the substrate. The flexible polymer substrate is made of polyethylene terephthalate, the surface of one side of the flexible polymer substrate is provided with a nanometer conical array structure, the height of a cone is 560nm, the diameter of the bottom of the cone is 290nm, the outer peripheral surface of the cone is a rough surface, the metal conducting layer is made of gold, and the thickness of the metal conducting layer is 180 nm.
As shown in fig. 1, the preparation method of the tapered array flexible electrode comprises the following steps:
(1) taking a polyethylene glycol terephthalate flexible substrate 10, cleaning the surface of the flexible substrate to remove surface dust and impurities, and drying the flexible substrate with nitrogen for later use;
(2) performing oxygen plasma treatment on the surface of the polyethylene glycol terephthalate 10 to make the surface hydrophilic, and then assembling a layer of polystyrene microsphere array 20 with the diameter of 800nm on the surface by an interface assembly method;
(3) the polystyrene microsphere 20 is used as a template, a plasma etcher is used for etching the flexible substrate provided with the polystyrene microsphere array 20, the size of the polystyrene microsphere 20 is gradually reduced in the etching process, the polyethylene terephthalate 10 below the polystyrene microsphere 20 is continuously etched, and finally the nano conical array structure 30 with the height of 560nm and the bottom diameter of 290nm is formed on the polyethylene terephthalate flexible substrate 10, and the conical peripheral surface is a rough surface, as shown in fig. 2a, the conical array structure can be obviously seen from the figure.
(4) A metal gold conducting layer 40 is sputtered on the surface of the polyethylene terephthalate substrate 10 with the nanometer conical array structure 30 through a magnetron sputtering coating method, the thickness of the metal conducting layer 40 is 180nm, and therefore the conical array flexible electrode is obtained, as shown in FIG. 2b, it can be seen from the figure that the metal conducting layer 40 is well deposited on the periphery of the conical array and the substrate between adjacent cones, and the deposited metal conducting layer 40 also keeps the conical shape corresponding to the polymer substrate.
Example 2
The tapered array flexible electrode in the embodiment 2 is different from the tapered array flexible electrode in the embodiment 1 only in that the tapered height of the nano tapered array structure on the surface of the flexible polymer substrate is 600nm, the diameter of the bottom of the nano tapered array structure is 240nm, and the thickness of the metal conducting layer is 55 nm.
The preparation method of the tapered array flexible electrode in the embodiment is basically the same as that in embodiment 1, except that the embodiment adopts polystyrene microspheres with the diameter of 1 μm as a template, and the specific plasma etching parameters are different from the magnetron sputtering process parameters.
An electron microscope image of the nano tapered array structure on the surface of the flexible polymer substrate prepared in this embodiment is shown in fig. 3a, and an electron microscope image of the tapered array flexible electrode finally obtained is shown in fig. 3 b.
Example 3
A tapered array flexible electrode includes a flexible polymer substrate and a metallic conductive layer attached to the substrate. The flexible polymer substrate is made of polyethylene glycol terephthalate, the surface of one side of the flexible polymer substrate is provided with a nanometer conical array structure, the height of a cone is 690nm, the diameter of the bottom of the cone is 380nm, the outer peripheral surface of the cone is a rough surface, the metal conducting layer is made of platinum, and the thickness of the metal conducting layer is 160 nm.
The method for preparing the tapered array flexible electrode in the embodiment is basically the same as that in embodiment 1, except that the embodiment adopts polystyrene microspheres with the diameter of 1 μm as a template, the target material for preparing the metal conducting layer by sputtering is a platinum target material, and the specific parameters of plasma etching are different from the parameters of magnetron sputtering.
An electron microscope image of the nano tapered array structure on the surface of the flexible polymer substrate prepared in this embodiment is shown in fig. 4a, and an electron microscope image of the tapered array flexible electrode finally obtained is shown in fig. 4 b.
Example 4
A tapered array flexible electrode includes a flexible polymer substrate and a metallic conductive layer attached to the substrate. The flexible polymer substrate is made of polyimide, a micrometer conical array structure is arranged on the surface of one side of the flexible polymer substrate, the height of a cone is 4.8 micrometers, the diameter of the bottom of the cone is 3.2 micrometers, the outer peripheral surface of the cone is a rough surface, the metal conducting layer is made of platinum, and the thickness of the metal conducting layer is 280 nm.
As shown in fig. 5, the method for preparing the tapered array flexible electrode comprises the following steps:
(1) taking a monocrystalline silicon wafer 11, and cleaning the surface of the monocrystalline silicon wafer to remove organic and inorganic impurities on the surface; the specific cleaning steps are as follows: ultrasonic cleaning in acetone, absolute ethyl alcohol and ultrapure water in sequence, drying in an oven after drying by nitrogen, and removing water vapor attached to the substrate;
(2) performing oxygen plasma treatment on the silicon wafer 11 to make the surface hydrophilic, uniformly spin-coating a layer of polyimide on the surface of the substrate by using a spin coater, heating at 100 ℃ for 3min, then heating in a 300 ℃ oven for 0.5h to crosslink the polyimide, and adjusting the rotating speed to obtain a polyimide film 12 with the thickness of 8 microns;
(3) performing oxygen plasma treatment on the polyimide film 12 to make the surface of the polyimide film hydrophilic, and assembling a layer of hexagonal close-packed polystyrene microsphere array 13 with the diameter of 5 mu m on the polyimide film by an interface assembly method;
(4) the method comprises the following steps of taking polystyrene microspheres 13 as a template, etching the polyimide film 12 assembled with the polystyrene microsphere array 13 by using a plasma etching machine, wherein the size of the polystyrene microspheres 13 is gradually reduced in the etching process, the polyimide 12 below the polystyrene microspheres is continuously etched, and finally a micrometer conical array 14 with the height of 4.8 micrometers and the bottom diameter of 3.2 micrometers is formed on the polyimide film 12, wherein the conical peripheral surface is a rough surface, as shown in fig. 6 a.
(5) And sputtering a metal gold conducting layer 15 on the surface of the polyimide base on which the micron conical array structure 14 is formed by a magnetron sputtering coating method, wherein the thickness of the metal conducting layer 15 is 280nm, so as to obtain the conical array flexible electrode, as shown in fig. 6 b.
Example 5
The tapered array flexible electrode of the embodiment 5 is different from the tapered array flexible electrode of the embodiment 4 only in that the tapered height of the micrometer tapered array structure on the surface of the flexible polymer substrate is 4.7 μm, the diameter of the bottom of the micrometer tapered array structure is 3.5 μm, and the thickness of the metal conducting layer is 200 nm.
The preparation method of the tapered array flexible electrode in the embodiment is basically the same as that in the embodiment 4, and the specific parameters of plasma etching and magnetron sputtering are different.
An electron microscope image of the micro tapered array structure on the surface of the flexible polymer substrate prepared in this example is shown in fig. 7a, and an electron microscope image of the tapered array flexible electrode finally obtained is shown in fig. 7 b.
Example 6
A tapered array flexible electrode includes a flexible polymer substrate and a metallic conductive layer attached to the substrate. The flexible polymer substrate is made of parylene, the surface of one side of the flexible polymer substrate is provided with a micron conical array structure, the height of a cone is 3.6 mu m, the diameter of the bottom of the cone is 1.8 mu m, the outer peripheral surface of the cone is a rough surface, the metal conducting layer is made of gold, and the thickness of the metal conducting layer is 150 nm.
The preparation method of the tapered array flexible electrode comprises the following steps:
(1) taking a monocrystalline silicon piece, and cleaning the surface of the monocrystalline silicon piece to remove organic and inorganic impurities on the surface; the specific cleaning steps are as follows: ultrasonic cleaning in acetone, absolute ethyl alcohol and ultrapure water in sequence, drying in an oven after drying by nitrogen, and removing water vapor attached to the substrate;
(2) depositing a parylene film on a silicon wafer by adopting a chemical vapor deposition preparation method, wherein the raw material of the parylene film is a xylene ring dimer, and the parylene film is gasified at 150 ℃, pyrolyzed at 650 ℃ and deposited at 20 ℃;
(3) carrying out oxygen plasma treatment on the parylene film to make the surface of the parylene film hydrophilic, and assembling a layer of hexagonal close-packed polystyrene ball array with the diameter of 5 mu m on the parylene film by an interface method;
(4) the polystyrene microsphere is used as a template, a plasma etcher is adopted to etch the flexible substrate assembled with the polystyrene microsphere array, the size of the polystyrene microsphere is gradually reduced in the etching process, the parylene below the polystyrene microsphere is continuously etched, and finally a micrometer conical array with the height of 3.6 mu m and the bottom diameter of 1.8 mu m is formed on the parylene flexible substrate, and the peripheral surface of the cone is a rough surface.
(5) A metal gold conducting layer is sputtered on the surface of the parylene substrate with the micron conical array structure through a magnetron sputtering coating method, the thickness of the metal conducting layer is 150nm, and therefore the conical array flexible electrode is obtained, and the gold conducting layer of the electrode is good in adhesion with a polymer substrate.
Example 7
A tapered array flexible electrode includes a flexible polymer substrate and a metallic conductive layer attached to the substrate. The flexible polymer substrate is made of polydimethylsiloxane, the surface of one side of the flexible polymer substrate is provided with a nanometer conical array structure, the height of a cone is 10.4 micrometers, the diameter of the bottom of the cone is 3.7 micrometers, the outer peripheral surface of the cone is a rough surface, the metal conducting layer is made of gold, and the thickness of the metal conducting layer is 300 nm.
The preparation method of the tapered array flexible electrode comprises the following steps:
(1) taking a monocrystalline silicon piece, and cleaning the surface of the monocrystalline silicon piece to remove organic and inorganic impurities on the surface; the specific cleaning steps are as follows: ultrasonic cleaning in acetone, absolute ethyl alcohol and ultrapure water in sequence, drying in an oven after drying by nitrogen, and removing water vapor attached to the substrate;
(2) preparing a polydimethylsiloxane solution according to the proportion of 10:1, stirring vigorously, vacuumizing until no bubbles exist, pouring the polydimethylsiloxane solution onto a treated silicon substrate, and heating at 60 ℃ for 3 hours to obtain the polydimethylsiloxane flexible film layer. The thickness of the film layer can be regulated by regulating the amount of the filled polydimethylsiloxane solution.
(3) Performing oxygen plasma treatment on the polydimethylsiloxane film to make the surface of the polydimethylsiloxane film hydrophilic, and assembling a layer of hexagonal close-packed polystyrene sphere array with the diameter of 15 mu m on the polydimethylsiloxane film by an interface method;
(4) the method comprises the following steps of taking polystyrene microspheres as a template, etching the flexible substrate assembled with the polystyrene microsphere array by using a plasma etching machine, gradually reducing the size of the polystyrene microspheres in the etching process, continuously etching polydimethylsiloxane below the polystyrene microspheres, and finally forming a micron conical array with the height of 10.4 mu m and the diameter of 3.7 mu m on the polydimethylsiloxane flexible substrate, wherein the peripheral surface of the cone is a rough surface.
(5) A metal gold conducting layer is sputtered on the surface of the polydimethylsiloxane base formed with the micron conical array structure by a magnetron sputtering coating method, the thickness of the metal conducting layer is 300nm, and therefore the conical array flexible electrode is obtained, and the gold conducting layer of the electrode is good in adhesion with a polymer substrate.
Example 8
A tapered array flexible electrode includes a flexible polymer substrate and a metallic conductive layer attached to the substrate. The material of the flexible polymer substrate is photoresist SU8, one side surface of the flexible polymer substrate is provided with a micron conical array structure, the height of a cone is 6.2 mu m, the diameter of the bottom of the cone is 3.8 mu m, the outer peripheral surface of the cone is a rough surface, the material of the metal conducting layer is platinum, and the thickness of the metal conducting layer is 100 nm.
The preparation method of the tapered array flexible electrode comprises the following steps:
(1) taking a monocrystalline silicon piece, and cleaning the surface of the monocrystalline silicon piece to remove organic and inorganic impurities on the surface; the specific cleaning steps are as follows: ultrasonic cleaning in acetone, absolute ethyl alcohol and ultrapure water in sequence, drying in an oven after drying by nitrogen, and removing water vapor attached to the substrate;
(2) performing oxygen plasma treatment on the silicon wafer to make the surface of the silicon wafer hydrophilic, uniformly spin-coating SU8 on the surface of a substrate by using a spin coater, baking for 10min at 95 ℃, performing ultraviolet exposure, baking for 5min at 95 ℃ to make the silicon wafer crosslinked, and adjusting the rotating speed to obtain an SU8 film with a certain thickness;
(3) performing oxygen plasma treatment on the SU8 film to make the surface of the SU8 film hydrophilic, and assembling a layer of hexagonal close-packed polystyrene microsphere array with the diameter of 10 mu m on the SU8 film by an interface method;
(4) the polystyrene microsphere is used as a template, a plasma etcher is adopted to etch the flexible substrate assembled with the polystyrene microsphere array, the size of the polystyrene microsphere is gradually reduced in the etching process, SU8 below the polystyrene microsphere is continuously etched, and finally the SU8 flexible substrate is formed into a micron conical array with the height of 6.2 mu m and the diameter of the bottom of 3.8 mu m, and the peripheral surface of the cone is a rough surface.
(5) A metal platinum conducting layer is sputtered on the surface of an SU8 substrate with a micron conical array structure by a magnetron sputtering coating method, the thickness of the metal conducting layer is 100nm, and therefore the conical array flexible electrode is obtained, and the platinum conducting layer of the electrode is good in adhesion with a polymer substrate.
Example 9
The tapered array flexible electrode of the present example 9 is different from that of the example 8 only in that the tapered height of the micrometer tapered array structure on the surface of the flexible polymer substrate is 72 μm, the diameter of the bottom is 66 μm, and the thickness of the metal conductive layer is 300 nm.
Example 10
As shown in fig. 8, an implantable electrode includes a plurality of stimulation sites 60, and the stimulation sites 60 are provided with a tapered array of flexible electrodes according to embodiment 1 of the present invention. The implanted resistance of the implanted electrode is 2-3 k omega, and the charge storage value of the stimulation site is 20mC/cm2。
It should be noted that, according to the disclosure and the explanation of the above description, the person skilled in the art to which the present invention pertains may make variations and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some equivalent modifications and variations of the present invention should be covered by the protection scope of the claims of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims (9)
1. A tapered array flexible electrode, comprising:
the flexible polymer substrate is provided with a micro-nano conical array structure on one side surface, wherein the outer peripheral surface of the micro-nano conical array structure is a rough surface; the micro-nano conical array structure is prepared by the following method: subjecting the flexible polymeric substrate to a hydrophilization treatment; assembling a layer of colloidal crystals on the surface of the flexible polymer substrate subjected to hydrophilization treatment; etching the flexible polymer substrate by using the colloidal crystal as a template and adopting a plasma etching method to obtain the flexible polymer substrate with a micro-nano tapered array structure formed on the surface of one side;
the metal conducting layer completely covers the peripheral surface of the micro-nano cone and completely covers an area, not provided with the micro-nano cone, on the surface of one side of the flexible polymer substrate;
the outer peripheral surface of the micro-nano conical body is provided with a plurality of concave structures extending longitudinally to form the rough surface; the diameter of the bottom of the micro-nano cone is 200nm-800nm, and the height of the micro-nano cone is 200nm-1 μm.
2. The tapered array flexible electrode according to claim 1, wherein the material of the flexible polymer substrate comprises at least one of polyimide, polydimethylsiloxane, polyethylene terephthalate, parylene, and photoresist.
3. The tapered array flexible electrode of claim 1, wherein the thickness of the metal conductive layer is 50nm to 300 nm.
4. The tapered array flexible electrode according to claim 1, wherein the material of the metal conductive layer comprises at least one of platinum, gold, platinum-iridium alloy, titanium nitride, iridium oxide and indium tin oxide.
5. A method for preparing a tapered array flexible electrode is characterized by comprising the following steps:
providing a flexible polymer substrate and performing a hydrophilization treatment;
assembling a layer of colloidal crystals on the surface of the flexible polymer substrate subjected to hydrophilization treatment;
etching the flexible polymer substrate by using the colloidal crystal as a template and adopting a plasma etching method to obtain the flexible polymer substrate with a micro-nano conical array structure formed on one side surface, wherein the outer peripheral surface of the micro-nano conical structure is a rough surface;
depositing a metal conducting layer on the flexible polymer substrate, wherein the metal conducting layer completely covers the peripheral surface of the micro-nano cone and completely covers an area, which is not provided with the micro-nano cone, on the surface of one side of the flexible polymer substrate; the outer peripheral surface of the micro-nano conical body is provided with a plurality of concave structures extending longitudinally to form the rough surface; the diameter of the bottom of the micro-nano cone is 200nm-80 μm, and the height of the micro-nano cone is 200nm-1 μm.
6. The method according to claim 5, wherein the colloidal crystal is at least one of a polymethylmethacrylate microsphere, a polystyrene microsphere, and a silica microsphere.
7. The method according to claim 5, wherein the metal conductive layer is formed by magnetron sputtering or electron beam evaporation coating.
8. An implantable electrode comprising a tapered array of flexible electrodes according to any one of claims 1 to 4.
9. A flexible electronic skin comprising a tapered array of flexible electrodes according to any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811297992.3A CN109205551B (en) | 2018-11-01 | 2018-11-01 | Tapered array flexible electrode and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811297992.3A CN109205551B (en) | 2018-11-01 | 2018-11-01 | Tapered array flexible electrode and preparation method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109205551A CN109205551A (en) | 2019-01-15 |
| CN109205551B true CN109205551B (en) | 2021-04-09 |
Family
ID=64998380
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811297992.3A Active CN109205551B (en) | 2018-11-01 | 2018-11-01 | Tapered array flexible electrode and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109205551B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109592635B (en) * | 2019-01-22 | 2020-08-11 | 杭州电子科技大学 | Method for controllably preparing composite nano pattern array |
| US20210260368A1 (en) * | 2019-07-09 | 2021-08-26 | Shenzhen Institutes Of Advanced Technology | Microelectrode, preparation method thereof and neural prosthesis |
| CN110540672B (en) * | 2019-09-27 | 2024-03-19 | 深圳先进技术研究院 | Anti-inflammatory polymer material and preparation method and application thereof |
| CN110878147B (en) * | 2019-11-05 | 2021-08-17 | 嘉兴学院 | Multi-section bar code nanorod and preparation method thereof |
| CN111017867B (en) * | 2019-11-21 | 2023-03-17 | 厦门大学 | Preparation method and application of network structure silicon-based lattice |
| CN110811594A (en) * | 2019-11-22 | 2020-02-21 | 中国科学院电子学研究所 | Wireless wearable nerve signal detection device and system |
| CN113620236A (en) * | 2020-05-06 | 2021-11-09 | 中国科学院微电子研究所 | Array preparation method of organic semiconductor material |
| CN112546434A (en) * | 2020-12-11 | 2021-03-26 | 深圳先进技术研究院 | Implantable flexible microelectrode array and preparation method thereof |
| CN112932412B (en) * | 2021-01-20 | 2023-10-13 | 华南理工大学 | Self-adhesion electronic skin based on multiple reversible bonding effect and preparation method and application thereof |
| CN113280840A (en) * | 2021-05-13 | 2021-08-20 | 桂林电子科技大学 | Plasma optical sensor based on gold nano rectangular pyramid structure polarization correlation |
| CN113916416B (en) * | 2021-09-23 | 2023-05-16 | 北京科技大学 | High-permeability strain non-sensitive electronic skin and preparation method thereof |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101398614B (en) * | 2008-09-12 | 2011-03-16 | 北京大学 | Method for making three-dimensional needlepoint electrode array based on parylene |
| ITRM20130079A1 (en) * | 2013-02-12 | 2014-08-13 | Consiglio Nazionale Ricerche | METHOD FOR THE PRODUCTION OF A MICRO-NEEDLE LAYER |
| CN106315505B (en) * | 2016-08-24 | 2018-11-06 | 深圳先进技术研究院 | A method of the adhesion strength between enhancing polyimide substrate and conductive metal layer |
| CN108195491B (en) * | 2017-12-14 | 2020-05-08 | 中国科学院深圳先进技术研究院 | Flexible pressure sensor and preparation method thereof |
| CN108553755A (en) * | 2018-05-03 | 2018-09-21 | 国家纳米科学中心 | A kind of flexible 3 D nerve electrode and preparation method thereof |
-
2018
- 2018-11-01 CN CN201811297992.3A patent/CN109205551B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN109205551A (en) | 2019-01-15 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109205551B (en) | Tapered array flexible electrode and preparation method thereof | |
| CN108751116B (en) | Warping type flexible electrode for bioelectricity recording or electric stimulation and preparation method thereof | |
| US7465661B2 (en) | High aspect ratio microelectrode arrays | |
| CN101204603B (en) | Embedded MENS bioelectrode and preparation technology thereof | |
| Nguyen‐Vu et al. | Vertically aligned carbon nanofiber arrays: an advance toward electrical–neural interfaces | |
| US7905013B2 (en) | Method for forming an iridium oxide (IrOx) nanowire neural sensor array | |
| US7494840B2 (en) | Optical device with IrOx nanostructure electrode neural interface | |
| Rui et al. | Parylene-based implantable Pt-black coated flexible 3-D hemispherical microelectrode arrays for improved neural interfaces | |
| US20060173263A1 (en) | Neural interface assembly and method for making and implanting the same | |
| US20110184269A1 (en) | Implantable probe | |
| CN110327544B (en) | Implanted high-density electrode point flexible probe electrode and preparation method thereof | |
| CN110540672B (en) | Anti-inflammatory polymer material and preparation method and application thereof | |
| US20210371987A1 (en) | Porous platinum nanorod electrode array flexible sensor devices and fabrication | |
| Bhandari et al. | A novel masking method for high aspect ratio penetrating microelectrode arrays | |
| CN112717273B (en) | Nerve electric stimulation electrode with micro-columnar structure and preparation method thereof | |
| CN112546434A (en) | Implantable flexible microelectrode array and preparation method thereof | |
| Khalifa et al. | A novel method for the fabrication of a high-density carbon nanotube microelectrode array | |
| US10639472B2 (en) | Process for manufacturing an implant for focal electrical stimulation of a nervous structure | |
| CN115591025B (en) | Nerve regulation device, preparation method and application thereof | |
| KR20210099262A (en) | Carbon nanotube microelectrode applicable to artificial retina | |
| CN101973509A (en) | Silicon micro needle surface coating process method based on micro-electromechanical system (MEMS) technology | |
| CN115893298A (en) | Bionic three-dimensional soft elastic cortex microelectrode and preparation method thereof | |
| CN207871274U (en) | A kind of Neural stimulation electrodes | |
| Leber et al. | Novel method of fabricating self-dissolvable and freely floating neural array | |
| Nolta et al. | Recessed traces for planarized passivation of chronic neural microelectrodes |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |