KR100844143B1 - Method for fabricating for three dimensional structured micro-electrode array - Google Patents

Abstract

A method for fabricating a micro-electrode array having a three-dimensional structure is provided to minimize an influence to a peripheral biological tissue by forming a flexible substrate with a first and second polymer material layers. A three-dimensional structure is formed by etching and removing a part of a process supporting substrate. A first and second conductive layers are formed on the process supporting substrate. A micro-electrode including a first and second micro-electrodes(102a,103a) is formed by planarizing a first and second conductive layers. A first polymer material layer(104) is formed on the process supporting substrate including the micro-electrode. The first polymer material layer is selectively patterned to expose a surface of the micro-electrode. A micro-metal line(105) is formed by forming and patterning a third conductive layer on the first polymer material layer. A pad(105a) is formed by forming and patterning a second polymer material(106) on the process supporting substrate. The process supporting substrate is etched and removed.

Description

Method for fabricating three-dimensional structure microelectrode array {Method for fabricating for three dimensional structured micro-electrode array}

1A to 1F are process flowcharts illustrating a method of manufacturing a fine electrode array having a three-dimensional structure according to an embodiment of the present invention.

2A and 2B are perspective views each showing an etched, removed prism structure, pyramid structure according to one embodiment of the present invention.

Figure 3a and Figure 3b is a photo showing the microelectrode of the prism structure, the fine electrode of the pyramid structure produced in accordance with an embodiment of the present invention, respectively.

Description of the main parts of the drawing

101: process support substrate 102a: first fine electrode

103a: second fine electrode 104: first polymer material layer

105: fine metal wire 105a: pad

106: second polymer material layer

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The present invention relates to a method for manufacturing a microelectrode array having a three-dimensional structure, and more particularly, by implementing the microelectrode in a three-dimensional structure to increase the contactable area to ensure stable contact with the contact object, and to implant the living body in vivo The present invention relates to a three-dimensional microelectrode array manufacturing method capable of minimizing physical influence on tissues.

Recent research on neural networks has led to the development of neural prosthetic devices that interpret signals transmitted to damaged nerves and deliver normal signals corresponding to the interpreted signals to surrounding normal nerves. Cochlear implants are the foremost field, and research on artificial visual devices, olfactory devices, and prosthetic and prosthetic limbs is also underway.

On the other hand, neural network research requires an electrode that directly contacts the nerve, records the nerve signal, and delivers the intended signal to the nerve. Recently, with the development of micro-machining technology, commercial electrodes used for research of neural signals have been replaced by micro-electrodes.

Looking at the conventional microelectrodes fabricated by micromachining techniques, the microelectrode structure is generally a two-dimensional planar structure and the microelectrode is recessed in the hole of the insulating film. As the fine electrode is provided in a recessed shape in the hole of the insulating film and the fine electrode has a two-dimensional planar structure, the contactable area becomes small, which causes a problem of contact failure when contacting a contact object such as a nerve. have.

The present invention has been made to solve the above problems, by implementing a micro-electrode in a three-dimensional structure to increase the contactable area to ensure stable contact with the contact object, physical impact on the living tissue during implantation in vivo It is an object of the present invention to provide a method of manufacturing a fine electrode array having a three-dimensional structure that can minimize the number.

In accordance with an aspect of the present invention, there is provided a method of manufacturing a fine electrode array having a three-dimensional structure, comprising: preparing a process supporting substrate, etching and removing a portion of the process supporting substrate in the form of a three-dimensional structure; And sequentially stacking a first conductive layer and a second conductive layer on the entire surface of the process supporting substrate, and planarizing the first and second conductive layers so that the surface of the process supporting substrate is exposed. Forming a microelectrode comprising a microelectrode, and stacking a first polymer material layer on the front surface of the process supporting substrate including the microelectrode and selectively patterning the first polymer material layer to expose the surface of the microelectrode. Forming a fine metal wire by laminating and selectively patterning a third conductive layer on the first polymer material layer; Stacking a second polymer material layer on an entire surface of the process support substrate, including patterning the second polymer material layer to expose one surface of the fine metal wire, and etching the process support substrate; It characterized in that it comprises a step of removing.

In addition, the first and second conductive layers may be made of the same material or different materials. In one embodiment, gold, platinum, nickel, aluminum, copper, iridium, iridium oxide, indium tin oxide (ITO), and polypyrrole (Poly pyrrole), any one of polycrystalline silicon doped with a high concentration of impurities is used.

On the other hand, the process supporting substrate etched, removed form is pyramid structure, prism structure, tetrahedral structure, pentagonal structure, polyhedron structure, square pillar structure, pentagonal pillar structure, hexagonal pillar structure, polygonal pillar structure, cylinder structure or conical structure .

The first and second polymer material layers may be made of the same material or different materials, and the first and second polymer material layers may be poly dimethyl siloxane (PDMS), poly carbonate (Poly carbonate), or poly methyl (PMMA). It is composed of any one of methacrylate), cyclo olefin copolymer (COC), polyimide (Polyimide), parylene (Parylene) or a combination thereof.

According to a feature of the present invention, by forming a flexible substrate using the first and second polymer material layers, even when implanted in a living body, the influence on surrounding biological tissues can be minimized. As the fine electrode of the dimensional structure is provided, close contact is possible to a contact object such as a nerve, and ultimately accurate signal transmission is possible.

Hereinafter, a method of manufacturing a fine electrode array having a three-dimensional structure according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. 1A to 1F are flowcharts illustrating a method of manufacturing a fine electrode array having a three-dimensional structure according to an embodiment of the present invention.

First, as shown in FIG. 1A, the process supporting substrate 101 is prepared. The process supporting substrate 101 serves to provide a space in which a series of processes for manufacturing a fine electrode array having a three-dimensional structure according to the present invention is performed. In one embodiment, a silicon substrate may be used. Subsequently, a predetermined portion of the process supporting substrate 101 is etched and removed by using dry etching or wet etching, such as reactive ion etching (RIE). At this time, the shape of the etched or removed portion has the shape of three-dimensional structure, and in detail, pyramid structure, tetrahedron structure, pentagonal structure, polyhedron structure, square pillar structure, pentagonal pillar structure, hexagonal pillar structure, polygonal pillar structure, cylinder It may be made of a structure or a cone structure. 2A and 2B are perspective views showing an etched, removed prism structure, and pyramid structure, respectively, according to an embodiment of the present invention.

Next, a process of sequentially forming the first conductive layer 102 and the second conductive layer 103 in a state where a predetermined portion of the process supporting substrate 101 is etched is performed. The first conductive layer 102 serves to record or transmit a neural signal in contact with a living body, and the second conductive layer 103 serves to provide a substantial form of a three-dimensional microelectrode.

Specifically, the first conductive layer 102 is laminated on the entire surface of the process supporting substrate 101. The first conductive layer 102 serves as a microelectrode in contact with a living body in the three-dimensional microelectrode array manufactured according to the present invention. The first conductive layer 102 should be selected in consideration of biocompatibility, amount of conversion charge per unit area, ease of processing, and the like. For example, gold, platinum, nickel, aluminum, copper, iridium, iridium oxide, and ITO ( Any one of a metal or metal compound such as Indium Tin Oxide, a conductive polymer such as polypyrrole, and polycrystalline silicon doped with a high concentration of impurities may be used.

In the state in which the first conductive layer 102 is plated on the process support substrate 101, the second conductive layer 103 is stacked on the first conductive layer 102. When the second conductive layer 103 is stacked, the second conductive layer 103 is stacked to fill all of the etching portions of the process supporting substrate 101. The second conductive layer 103 serves as a form of fine electrode in the three-dimensional fine electrode array manufactured according to the present invention. Here, the material of the second conductive layer 103 should be considered in terms of mechanical strength, electrical conductivity, ease of processing, etc., and may be made of the same material or different materials from the first conductive layer 102. That is, like the first conductive layer 102, a metal or a metal compound such as gold, platinum, nickel, aluminum, copper, iridium, iridium oxide, indium tin oxide (ITO), a conductive polymer such as poly pyrrole, Any one of polycrystalline silicon doped with a high concentration of impurities may be used.

An electroplating process may be used as a specific lamination example of the first conductive layer 102 and the second conductive layer 103. When using a plating process, a first conductive layer 102 is deposited on the entire surface of the process supporting substrate 101 to serve as a seed layer, and the second conductive layer 103 is a seed layer. Is deposited on the first conductive layer 102 to be electroplated.

In a state where the first and second conductive layers 102 and 103 are sequentially stacked, the surface of the process supporting substrate 101 is exposed by using a chemical mechanical polishing (CMP) process as shown in FIG. 1B. The first and second conductive layers 102 and 103 are planarized to be flat. As a result, the first and second conductive layers 102 and 103 remain only at the etching portion of the substrate, and the first and second conductive layers 102 and 103 remaining in the substrate respectively have a first fine electrode. A fine electrode 110 having a three-dimensional structure, referred to as 102a and a second fine electrode 103a and composed of the first and second fine electrodes 102a and 103a, is completed.

In the state where the fine electrode 110 having the three-dimensional structure is completed, as shown in FIG. 1C, the first polymer material layer 104 is stacked on the entire surface of the process supporting substrate 101 including the fine electrode 110. do. The first polymer material layer 104 is selected from poly dimethyl siloxane (PDMS), poly carbonate (poly carbonate), poly methyl methacrylate (PMMA), cyclo olefin copolymer (COC), polyimide, and parylene. It may be composed of any one or a combination thereof. Thereafter, the first polymer material layer 104 is selectively patterned to expose the surface of the microelectrode 110 using photolithography and etching processes.

Subsequently, as shown in FIG. 1D, after stacking a third conductive layer on the entire surface of the process supporting substrate 101 including the first polymer material layer 104, the third conductive layer is selectively patterned to form a fine metal wire. Form 105. Here, the third conductive layer may be made of a metal material such as chromium, copper, gold, aluminum, platinum, nickel.

Next, as shown in FIG. 1E, the second polymer material layer 106 is stacked on the entire surface of the substrate including the fine metal wire 105, and the second polymer material layer 106 is selectively patterned to form the fine metal wire. The predetermined portion of 105 is exposed. In this case, the exposed surface of the fine metal wire 105 is defined as a pad 105a that performs electrical connection with the outside. In addition, the second polymer material layer 106 may be made of the same material or different materials as the first polymer material layer 104, and like the first polymer material layer 104, poly dimethyl siloxane ), Poly carbonate (Poly carbonate), poly methyl methacrylate (PMMA), cyclo olefin copolymer (COC), polyimide (Polyimide), parylene (Parylene) may be composed of any one or a combination thereof.

In this state, finally, as shown in FIG. 1F, when the process support substrate 101 is removed through dry or wet etching, the method for manufacturing a fine electrode array having a three-dimensional structure according to the present invention is completed, and as a result, FIG. 1F. There is provided a fine electrode array having a three-dimensional structure as shown in FIG. Referring to the microelectrode array having a three-dimensional structure shown in FIG. 1F, the flexible substrate 120 including the first and second polymer material layers 104 and 106, and the first and second substrates disposed on the flexible substrate 120 are provided. It can be seen that the fine electrode having a three-dimensional structure including the second fine electrodes 102a and 103a and the fine metal line 105 provided inside the flexible substrate 120. For reference, FIGS. 3A and 3B are photographs showing micro electrodes of a prism structure and pyramidal structures, respectively, manufactured according to an embodiment of the present invention.

The method of manufacturing a three-dimensional fine electrode array according to the present invention has the following effects.

By configuring the flexible substrate using the first and second polymer material layers, even when implanted in a living body, the influence on the surrounding biological tissues can be minimized, and the microelectrode having a three-dimensional structure is provided to protrude on the substrate. As a result, close contact with a contact object such as a nerve becomes possible and ultimately accurate signal transmission is possible.

Claims (7)

Preparing a process support substrate; Etching and removing a portion of the process support substrate in the form of a three-dimensional structure; Sequentially stacking a first conductive layer and a second conductive layer on the entire surface of the process supporting substrate; Planarizing the first and second conductive layers to expose the surface of the process supporting substrate to form a fine electrode composed of the first and second fine electrodes; Stacking the first polymer material layer on the front surface of the process supporting substrate including the microelectrode and selectively patterning the first polymer material layer to expose the surface of the microelectrode; Stacking and selectively patterning a third conductive layer on the first polymer material layer to form a fine metal wire; Stacking a second polymer material layer on an entire surface of the process supporting substrate including the fine metal wires, and then patterning the second polymer material layer to expose one surface of the fine metal wires to form a pad; And 3. The method of claim 3, further comprising etching and removing the process supporting substrate. The method of claim 1, wherein the first and second conductive layers are made of the same material or different materials. The method of claim 1, wherein the first and second conductive layers are gold, platinum, nickel, aluminum, copper, iridium, iridium oxide, indium tin oxide (ITO), poly pyrrole, polycrystalline doped with a high concentration of impurities. Method for producing a fine electrode array of a three-dimensional structure characterized in that using any one of silicon. The method of claim 1, wherein the process supporting substrate is etched, removed form pyramid structure, prism structure, tetrahedral structure, pentagonal structure, polyhedral structure, rectangular pillar structure, pentagonal pillar structure, hexagonal pillar structure, polygonal pillar structure, cylindrical structure Or a three-dimensional structure of the fine electrode array, characterized in that the conical structure. The method of claim 1, wherein the first and second polymer material layers are made of the same material or different materials. The method of claim 1, wherein the first and second polymer material layers are poly dimethyl siloxane (PDMS), poly carbonate (Poly carbonate), poly methyl methacrylate (PMMA), cyclo olefin copolymer (COC), polyimide (Polyimide), A method of manufacturing a fine electrode array having a three-dimensional structure, characterized in that composed of any one of parylene (Parylene) or a combination thereof. The method of claim 1, The first and second conductive layers use a plating process, the plating process, Stacking a first conductive layer as a seed layer on the entire surface of the process supporting substrate; The method of manufacturing a fine electrode array having a three-dimensional structure characterized in that it consists of plating and laminating the second conductive layer on the first conductive layer.

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