WO2016201746A1

WO2016201746A1 - Flexible neural microelectrode array provided with hollow protrusion structure, and manufacturing method therefor

Info

Publication number: WO2016201746A1
Application number: PCT/CN2015/083586
Authority: WO
Inventors: 张贯京; 陈兴明; 葛新科; 普拉纽克·克里斯基捏; 古列莎·艾琳娜; 波达别特·伊万
Original assignee: 深圳市华科安测信息技术有限公司; 深圳市前海安测信息技术有限公司
Priority date: 2015-06-13
Filing date: 2015-07-08
Publication date: 2016-12-22
Also published as: CN105147280A

Abstract

A flexible neural microelectrode array provided with a hollow protrusion structure. The flexible neural microelectrode array provided with a hollow protrusion structure comprises a flexible substrate (1), an insulation layer (2), microelectrode units (3), wires (4), and wire welding spots (5). The microelectrode units (3), the wires (4), and the wire welding spots (5) are disposed on the flexible substrate (1). The microelectrode units (5) and the wire welding spots (5) are connected by means of the wires (4). The insulation layer (2) covers the flexible substrate (1). The microelectrode units (3) are exposed by exposing out of the insulation layer (2). The flexible substrate (1) is provided with multiple hollow protrusions (7) exposed out of the insulation layer (2). The microelectrode units (3) are disposed on the hollow protrusions (7) of the flexible substrate (1). Contact resistance and mechanical strength of microelectrodes can be effectively reduced. Also provided is a manufacturing method for the neural microelectrode array. The method comprises: coating the flexible substrate (1) on a template in spinning manner, then laying the microelectrode units (3), the wires (4) and the wire welding spots (5), then laying the insulation layer (2), and making the microelectrode units (3) exposed out of the insulation layer (2). The manufacturing process is simple, fast and convenient, and cost is low.

Description

Flexible nerve microelectrode array with hollow convex structure and preparation method thereof

Technical field

The invention relates to the field of biomedical devices, in particular to a flexible neural microelectrode array having a hollow convex structure and a preparation method thereof.

Background technique

In the medical diagnosis or the corresponding research, it is necessary to measure and record the internal potential of the human body or the animal to be studied. In addition, transcutaneous electrical stimulation is a commonly used method for assisting disease treatment in clinical practice. All kinds of medical measuring instruments need to communicate with the body through appropriate electrodes when performing bioelectrical detection and applying electrical stimulation to the patient. The electrical signal is transmitted when the bioelectrical detection is performed on the human nervous system. Neuromicroelectrode arrays have been widely studied and applied to nerve repair implantable devices in recent years due to their excellent biocompatibility and small damage to tissue. However, based on such a flexible substrate, it is generally a planar electrode array. Currently, the micro-scale flexible microelectrode exists in the absence of surface modification. There are two problems: 1. The presence of the insulating layer causes the metal electrode portion to be depressed. In the state, the electrode is difficult to form a good contact with the position to be measured as the size is reduced; 2. As the electrode size decreases, the surface impedance of the electrode increases, and the neuroelectrophysiological signal is generally weak, and the electrode surface An increase in impedance affects the measurement of the signal.

Summary of the invention

The main object of the present invention is to provide a flexible neural microelectrode array having a hollow convex structure capable of reducing contact resistance and a preparation method thereof, which can effectively improve the contact area between the flexible neural microelectrode and the part to be tested, and reduce the flexible nerve microelectrode. Contact impedance with the part to be tested.

Further, the present invention can also reduce the mechanical strength of the microelectrode site, and ensure that no damage is caused to the site to be tested while being in good contact with the site to be tested.

To achieve the above object, the present invention provides a flexible neural microelectrode array having a hollow convex structure, comprising a flexible substrate, an insulating layer, a microelectrode unit, a wire and a wire bonding pad, the microelectrode unit, the wire and the lead a solder joint is disposed on the flexible substrate, the microelectrode unit and the lead solder joint are connected by the wire, and the insulating layer covers the flexible substrate, The microelectrode unit is exposed on the insulating layer, and the flexible substrate is provided with a plurality of hollow protrusions exposed on the insulating layer, and the microelectrode unit is disposed on the hollow protrusion of the flexible substrate on.

Preferably, an adhesive layer is disposed on the hollow protrusion of the insulating layer, and the microelectrode unit is disposed on the adhesive layer.

Preferably, the insulating layer is provided with an opening at a position of the wire bonding point, and the wire bonding point is exposed through an opening of the insulating layer.

Preferably, the material of the adhesion layer comprises titanium, chromium, or an alloy containing one or two of the two elements, and the microelectrode unit is made of gold.

Preferably, the material of the flexible substrate comprises polydimethylsiloxane, and the material of the insulating layer comprises a photolithographic polydimethylsiloxane.

In addition, the present invention also provides a method for preparing a flexible neural microelectrode array having a hollow convex structure, comprising the following steps:

S100, spin coating a flexible substrate on the surface of the microelectrode template to form a flexible base layer with protrusions; the microelectrode is formed into a template having a plurality of convex plate shapes on the surface;

S200, depositing a microelectrode unit on a convex portion of the flexible base layer, laying a wire and a lead solder joint on the flexible base layer, and connecting the microelectrode unit and the lead solder joint through the wire;

S300, laying an insulating layer on the flexible substrate layer processed in step S200, and opening the insulating layer at the position of the microelectrode unit and the lead solder joint to make the microelectrode unit and the wire bonding Point is exposed through the insulating layer;

S400, separating the microelectrode fabrication template from the flexible substrate layer, that is, the flexible neural microelectrode array having the hollow convex structure.

Preferably, in step S200, before the microelectrode unit is deposited on the convex portion of the flexible substrate layer, an adhesion layer is first deposited on the convex portion of the flexible substrate layer, and then the microelectrode unit is deposited on the adhesion layer.

Preferably, the material of the microelectrode unit is gold, the material of the flexible substrate is polydimethylsiloxane, and the material of the insulating layer is lithable polydimethyl. Silicone.

Preferably, in step S200, a metal template having the same shape as that of the microelectrode is first used, and a preset position of the microelectrode unit, the wire, and the lead pad on the template is formed on the metal template with the microelectrode. Providing an opening at a corresponding position, and covering the metal template on the flexible substrate layer, then depositing a microelectrode unit on the convex portion of the flexible substrate layer through the opening on the metal template, laying the wire on the flexible substrate layer and Leading the solder joint, and connecting the microelectrode unit and the lead solder joint by wires, then depositing the microelectrode unit on the convex portion of the flexible base layer, and then forming the metal template from the microelectrode to form the flexible base on the template Separated on the bottom layer.

Preferably, the material of the adhesion layer comprises titanium, chromium, or an alloy containing one or both of these two elements.

The invention provides a flexible neural microelectrode array having a hollow convex structure, which comprises a flexible substrate, an insulating layer, a microelectrode unit, a wire and a lead solder joint, and the microelectrode unit, the wire and the lead solder joint are all disposed on the flexible substrate The microelectrode unit and the lead solder joint are connected by wires, the insulating layer is covered on the flexible substrate, and the microelectrode unit is exposed on the insulating layer. The flexible substrate in the present invention is provided with a plurality of hollow convex portions exposed on the insulating layer. The microelectrode unit is disposed on the hollow protrusion of the flexible substrate. Compared with the conventional flexible neuro microelectrode array, the microelectrode unit is disposed on the hollow protrusion on the flexible substrate in the present invention, compared to the planar type. The flexible substrate microelectrode, the microelectrode on the protrusion increases the surface area of the electrical stimulation site, can effectively reduce the contact resistance, and since the protrusion on the flexible substrate in the present invention is hollow, it can lower the microelectrode site The overall strength makes it difficult to damage the measured position during use;

The invention also provides a method for preparing a flexible neural microelectrode array having a hollow convex structure, using a plate-shaped microelectrode with a plurality of protrusions to form a template, and spin coating a flexible base layer on the microelectrode fabrication template, and then A wire and a wire bonding spot are laid on the flexible substrate layer, a micro electrode unit is deposited on the convex portion of the flexible substrate layer, and an insulating layer is laid on the flexible substrate layer, and the convex portion and the convex portion of the flexible substrate layer are microscopically The electrode unit is exposed to the insulating layer, and the manufacturing process is simple and quick, and the cost is low.

DRAWINGS

1 is a schematic perspective view of a flexible neural microelectrode array having a hollow convex structure in the present invention;

2 is a side cross-sectional view showing a flexible neural microelectrode array having a hollow convex structure in the present invention;

3 is a schematic side view showing the structure of a template prepared by using a microelectrode used in a method for preparing a flexible neural microelectrode array having a hollow convex structure according to the present invention;

4 is a schematic flow chart of a preparation method of a first embodiment of a method for preparing a flexible neural microelectrode array having a hollow convex structure according to the present invention;

FIG. 5 is a schematic flow chart of a preparation method of a second embodiment of a method for preparing a flexible neural microelectrode array having a hollow convex structure according to the present invention.

The implementation, functional features, and advantages of the present invention will be further described in conjunction with the embodiments.

detailed description

It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The present invention provides a flexible neural microelectrode array (hereinafter referred to as a microelectrode array) having a hollow convex structure. Referring to FIG. 1 and FIG. 2, FIG. 1 is a flexible neural microelectrode array having a hollow convex structure in the present invention. FIG. 2 is a side cross-sectional view of a flexible neural microelectrode array having a hollow convex structure according to the present invention. The flexible neural microelectrode array having a hollow convex structure includes a flexible substrate 1, an insulating layer 2, and a microelectrode. a unit 3, a wire 4 and a wire bonding point 5, the microelectrode unit 3, the wire 4 and the wire bonding pad 5 are disposed on the flexible substrate 1, the microelectrode unit 3 and the wire bonding point 5 is connected by the wire 4, the insulating layer 2 is covered on the flexible substrate 1, and the microelectrode unit 3 is exposed on the insulating layer 2, the flexible substrate 1 A plurality of hollow protrusions 7 exposed to the insulating layer 2 are provided, and the microelectrode unit 3 is disposed on the hollow protrusions 7 of the flexible substrate.

In the present invention, the flexible neural microelectrode array having a hollow convex structure employs a flexible substrate 1 having a hollow convex structure, the microelectrode unit 3 is deposited on the hollow projection on the flexible substrate 1, the wire 4 and the wire bonding The arrangement of the point 5 is similar to that of the conventional microelectrode array. The microelectrode unit 3 and the lead solder joint 5 can be connected by the wire 4 according to the corresponding arrangement of different kinds of microelectrode arrays, and the insulating layer 2 is covered on the flexible substrate 1 And the microelectrode unit 3 is exposed to the insulating layer 2, and when used, when the microelectrode array is attached to the portion to be tested, the microelectrode unit 3 of the present invention can be compared with the conventional microelectrode unit 3 The portion to be tested forms a larger contact area, that is, the microelectrode unit 3 on the convex structure of the flexible substrate 1 can increase the surface area of the electrode stimulation site, lower the contact resistance, and the hollow protrusion on the flexible substrate 1. The structure can also reduce the strength of the electrode sites of the microelectrode unit 3 without causing any damage to the measured position.

In a preferred embodiment, the insulating layer 2 is provided with an opening at the position of the lead solder joint 5, and the lead solder joint 5 is exposed through the opening of the insulating layer 2. The insulating layer 2 can also use a plurality of insulating layers of a single sheet structure. At this time, after the flexible substrate 1 is fabricated and the microelectrode unit 3, the wires, and the wire bonding pads 5 are laid on the flexible substrate 1, only A plurality of individual sheet-like insulating layers 2 are covered on the flexible substrate 1 to cover the wires 4, and the microelectrode unit 3 and the lead pads 5 are exposed.

In a preferred embodiment, an adhesive layer 6 is disposed on the hollow protrusion 7 of the insulating layer 2, and the microelectrode unit 3 is disposed on the adhesion layer 6, the microelectrode unit 3 and the adhesion layer. 6 is easier to combine, improving the stability of the microelectrode unit 3, making the microelectrode unit 3 more robust.

In a preferred embodiment, the material of the adhesive layer 6 comprises titanium, chromium, or an alloy containing one or two of the two elements, and the microelectrode unit 3 is made of gold. .

In a preferred embodiment, the material of the flexible substrate 1 comprises polydimethylsiloxane, and the material of the insulating layer comprises a photolithographic polydimethylsiloxane.

It is to be noted, however, that the materials of fabrication of all of the components of the present invention are not limited to the materials given above, and any conventional alternative materials that can be conceived by those skilled in the art are equivalent to the above-listed materials.

In the present invention, the shape of the protrusion on the flexible substrate 1 is not limited to the hollow hemisphere given in the drawings, and may be a hollow conical shape, a hollow pyramid, a quadrangular pyramid, a polygonal pyramid or the like, and The effect is similar to the hollow hemispherical projections of the present invention and is an equivalent replacement for the present invention and will not be enumerated here.

The invention also provides a preparation method of a flexible nerve microelectrode array having a hollow convex structure, and a schematic diagram of a preparation method of the first embodiment is shown in FIG. 4, and the template 8 is fabricated using a microelectrode, and the side structure diagram thereof is as follows. As shown in FIG. 3, the whole is plate-shaped, and a plurality of protrusions 801 are provided on the surface thereof. The preparation method of the flexible nerve microelectrode array having the hollow convex structure is prepared by the following steps:

In the above process flow, the template is first fabricated using the microelectrode shown in FIG. 3, and the flexible substrate is spin-coated on the microelectrode fabrication template. Since the microelectrode is formed with a plurality of protrusions on the template, the plurality of protrusions and the preparation to be prepared The hollow convex shape of the flexible neural microelectrode array having the hollow convex structure is matched, so after the spin-coated flexible substrate, the flexible substrate forms a plurality of hollow convex structures, and then the microelectrode unit is deposited on the hollow convex structure. And laying a wire and a wire bonding spot on the flexible substrate, connecting the micro electrode unit and the wire bonding point through the wire, and then laying an insulating layer on the flexible substrate, the insulating layer in the microelectrode unit, the wire bonding The position of the dot is opened, so that the microelectrode unit and the lead solder joint are exposed through the insulating layer. After the flexible substrate and the insulating layer are solidified, the microelectrode is formed into a template and separated from the flexible substrate layer. The flexible neural microelectrode array having a hollow convex structure, the preparation method of the flexible neural microelectrode array having the hollow convex structure in the invention is simple and fast It is easy to make, and it is cheap to produce and has high production efficiency.

In the method for preparing a flexible neural microelectrode array having a hollow convex structure in the present invention, a production process flow chart of the second embodiment is shown in FIG. 5, and the template 8 is fabricated using a microelectrode, and the side structure diagram thereof is as follows. As shown in Fig. 3, the whole is a plate shape, and a plurality of protrusions 801 are provided on the surface thereof, and are produced by the following steps:

S100, spin-coating a layer of polydimethylsiloxane as a flexible substrate on a surface of the microelectrode template to form a flexible base layer with protrusions;

S200', using a metal template having the same shape as the microelectrode to form a template, and setting an opening on the metal template at a position corresponding to a preset position of the microelectrode unit, the wire, and the lead pad on the microelectrode fabrication template. And covering the metal template on the flexible substrate layer, and then depositing a layer of titanium or chromium as an adhesion layer on the convex portion of the flexible substrate layer through the opening on the metal template, and then depositing a layer on the adhesion layer Layering gold as a microelectrode unit, laying a wire and a wire bonding spot on the flexible substrate layer, connecting the microelectrode unit and the wire bonding pad through the wire, and then forming the metal template from the microelectrode to form the flexible base on the template Separated on the bottom layer;

S300, laying an insulating layer on the flexible substrate layer processed by step S200', and opening the insulating layer at a position of the microelectrode unit and the lead solder joint to make the microelectrode unit and the lead wire Solder joints are exposed through the insulating layer;

In this embodiment, after spin coating a layer of polydimethylsiloxane as a flexible substrate on the microelectrode fabrication template, a metal template having the same shape as the microelectrode is used, and the metal template is fabricated on the microelectrode. Forming an opening at a position corresponding to a preset position of the microelectrode unit, the wire, and the lead pad on the template, covering the metal template on the flexible substrate layer, and then embossing the flexible substrate layer through the opening on the metal template A layer of titanium or chromium is deposited as an adhesion layer, and then a layer of gold is deposited on the adhesion layer as a microelectrode unit, wires and lead pads are laid on the flexible substrate layer, and the microelectrode unit and the lead pad are connected by wires. And then separating the metal template from the flexible substrate layer on the microelectrode fabrication template, using a metal template, according to a preset position of the microelectrode unit, the wire and the lead solder joint on the flexible substrate, on the metal template Correspondingly opening a plurality of openings, then laying the metal template on the flexible substrate, and then placing the microelectrodes on the flexible substrate through the openings in the metal template Yuan, wire and the bond pad, is connected via a wire after the unit between microelectrodes and a lead solder metal template is removed, it can be more easily produced microelectrode array.

As a preferred embodiment of the present invention, an optional material of the adhesive layer in the present invention includes titanium, chromium, or an alloy containing one or both of these two elements, and magnetron sputtering may be used for titanium or Chromium or an alloy containing one or both of these two elements is deposited on the convex portion of the flexible substrate, the material of the microelectrode unit is gold, and the materials of the flexible substrate may include but are not limited to Polydimethylsiloxane, the insulating layer may be selected from materials including, but not limited to, photolithographic polydimethylsiloxane.

The above are only the preferred embodiments of the present invention, and are not intended to limit the scope of the invention, and the equivalent structure or equivalent process transformations made by the description of the present invention and the drawings are directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Claims

A flexible neural microelectrode array having a hollow convex structure, comprising a flexible substrate, an insulating layer, a microelectrode unit, a wire and a wire bonding spot, wherein the microelectrode unit, the wire and the wire bonding point are disposed on the flexible substrate, The microelectrode unit and the lead solder joint are connected by the wire, the insulating layer covers the flexible substrate, and the microelectrode unit is exposed to the insulating layer. The flexible substrate is provided with a plurality of hollow protrusions exposed on the insulating layer, and the microelectrode unit is disposed on the hollow protrusion of the flexible substrate.
The flexible neural microelectrode array having a hollow convex structure according to claim 1, wherein an adhesive layer is disposed on the hollow protrusion of the insulating layer, and the microelectrode unit is disposed at the On the adhesive layer.
The flexible neural microelectrode array having a hollow convex structure according to claim 1, wherein said insulating layer is provided with an opening at a position of said lead solder joint, said lead solder joint passing said The opening of the insulating layer is exposed.
The flexible neural microelectrode array having a hollow convex structure according to claim 3, wherein an adhesive layer is disposed on the hollow protrusion of the insulating layer, and the microelectrode unit is disposed at the On the adhesive layer.
The flexible neural microelectrode array having a hollow convex structure according to claim 4, wherein the material of the adhesive layer comprises titanium, chromium, or one or both of the two elements. In the alloy, the material of the microelectrode unit is gold.
The flexible neural microelectrode array having a hollow convex structure according to claim 1, wherein the material of the flexible substrate comprises polydimethylsiloxane, and the material of the insulating layer comprises lithography. Polydimethylsiloxane.
The method for preparing a flexible neural microelectrode array having a hollow convex structure according to claim 1, comprising the steps of:

S100, spin coating a flexible substrate on the surface of the microelectrode template to form a flexible base layer with protrusions; the microelectrode is formed into a template having a plurality of convex plate shapes on the surface;

S200, depositing a microelectrode unit on a convex portion of the flexible base layer, laying a wire and a lead solder joint on the flexible base layer, and connecting the microelectrode unit and the lead solder joint through the wire;

S300, laying an insulating layer on the flexible substrate layer processed in step S200, and opening the insulating layer at the position of the microelectrode unit and the lead solder joint to make the microelectrode unit and the wire bonding Point is exposed through the insulating layer;

S400, separating the microelectrode fabrication template from the flexible substrate layer, that is, the flexible neural microelectrode array having the hollow convex structure.
A method of fabricating a flexible neural microelectrode array having a hollow convex structure according to claim 7, wherein in step S200, before depositing the microelectrode unit in the convex portion of the flexible substrate layer, first in the flexible base An adhesive layer is deposited on the raised portion of the underlayer, after which the microelectrode unit is deposited on the adhesion layer.
The method for preparing a flexible neural microelectrode array having a hollow convex structure according to claim 7, wherein the microelectrode unit is made of gold, and the flexible substrate is made of a material comprising poly Methyl siloxane, the insulating layer may be selected from materials including photolithographic polydimethylsiloxane.
The method for preparing a flexible neural microelectrode array having a hollow convex structure according to claim 7, wherein in step S200, a metal template having the same shape as that of the microelectrode is first used, on the metal template. Forming an opening at a position corresponding to a preset position of the microelectrode unit, the wire, and the lead pad on the microelectrode fabrication template, and covering the metal template on the flexible substrate layer, and then passing through the metal template Opening, depositing a microelectrode unit at a convex portion of the flexible substrate layer, laying a wire and a wire bonding spot on the flexible substrate layer, and connecting the microelectrode unit and the wire bonding pad through the wire, and then depositing a microscopic electrode on the convex portion of the flexible substrate layer An electrode unit is then separated from the flexible substrate layer on the microelectrode fabrication template.
A method of fabricating a flexible neural microelectrode array having a hollow convex structure as claimed in claim 10, wherein in step S200, before depositing the microelectrode unit in the convex portion of the flexible substrate layer, first in the flexible base An adhesive layer is deposited on the raised portion of the underlayer, after which the microelectrode unit is deposited on the adhesion layer.
The method for preparing a flexible neural microelectrode array having a hollow convex structure according to claim 11, wherein the material of the adhesive layer comprises titanium, chromium, or one of the two elements or Two alloys.
The method for preparing a flexible neural microelectrode array having a hollow convex structure according to claim 10, wherein the microelectrode unit is made of gold, and the flexible substrate is made of a material comprising poly Methyl siloxane, the insulating layer may be selected from materials including photolithographic polydimethylsiloxane.