Preparation method of an interventional brain-computer interface support and the support

Abstract

This invention provides a method for fabricating an interventional brain-computer interface (BCI) scaffold and the scaffold itself, belonging to the field of BCI scaffold technology. The method includes: Step S1, fabricating a scaffold substrate with a grooved structure, the grooved structure including electrode grooves and wire grooves; Step S2, sputtering a first insulating layer at the bottom of the electrode grooves; Step S3, sputtering a conductive layer on the first insulating layer; Step S4, filling the grooved structure above the conductive layer using an electroplating process to form a vertically oriented conductive circuit layer; Step S5, performing a first chemical mechanical polishing; Step S6, shielding the preset signal acquisition electrode positions; Step S7, sputtering a second insulating layer in the unshielded grooved structure area; Step S8, removing the shielding material and sputtering an electrode layer at the shielded position; Step S9, performing a second chemical mechanical polishing to form electrodes. This method primarily addresses the technical problems of low assembly accuracy and unstable interface contact caused by the later assembly of the scaffold, electrodes, and wires in existing technologies.

Description

Technical Field

[0001] This invention belongs to the field of brain-computer interface scaffold technology, specifically relating to a method for preparing an interventional brain-computer interface scaffold and the scaffold itself. Background Technology

[0002] Existing EEG signal acquisition devices are mainly divided into three categories: non-invasive, semi-invasive, and invasive. Non-invasive devices suffer from poor signal acquisition due to obstruction by the scalp and skull. While semi-invasive and invasive devices can improve signal quality (semi-invasive is superior to non-invasive, and invasive can obtain high-frequency, high-precision signals), they require invasive craniotomy and other traumatic surgeries, posing extremely high surgical risks. With the deep integration of neural engineering and biomedical engineering, interventional brain-computer interfaces (BCIs) have become a key technological direction for overcoming the insufficient signal accuracy of non-invasive BCIs and the high risks of invasive surgery. This is because they can be implanted through natural cavities such as blood vessels, allowing for high-precision interaction directly with neural tissue, while avoiding the significant risks of craniotomy. As the core carrier of this system, the fabrication process of the functionalized scaffold directly determines the signal transmission stability, long-term biocompatibility, and ultimate clinical applicability.

[0003] Currently, existing interventional stent fabrication methods are mainly based on traditional nickel-titanium alloy stent processing technology, typically involving laser cutting or etching of nickel-titanium alloy tubing to form a mesh stent structure with shape memory effect. However, these methods primarily focus on the mechanical support function of the stent and do not integrate the electrodes and functional coatings necessary for EEG signal acquisition. Therefore, after stent fabrication, electrodes for signal acquisition and leads for signal transmission need to be assembled or welded separately. This post-assembly method has inherent drawbacks such as low assembly precision, unstable interfacial contact resistance, and poor process consistency. Furthermore, existing technologies typically only perform two-dimensional circuit processing on the stent surface, failing to achieve vertical integration of circuits within the three-dimensional structure of the stent, making it difficult to ensure stable contact between all electrodes and nerve tissue in complex vascular environments.

[0004] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing an interventional brain-computer interface scaffold, so as to at least solve the technical problems of low assembly accuracy and unstable interface contact caused by the later assembly of the scaffold with electrodes and wires in the prior art.

[0006] To achieve the above objectives, the method for fabricating the interventional brain-computer interface scaffold of the present invention provides the following technical solution: A method for fabricating an interventional brain-computer interface scaffold includes the following steps: Step S1: Prepare a nickel-titanium alloy support substrate with a grooved structure, wherein the grooved structure includes an electrode groove for integrating electrodes and a wire groove for laying wires, and the electrode groove and the wire groove are connected. Step S2: Sputter a first insulating layer at the bottom of the electrode groove; Step S3: Sputter a conductive layer onto the first insulating layer; Step S4: Fill the groove structure above the conductive layer using TSV (Through-Silicon Via) electroplating process to form a vertical conductive circuit layer; Step S5: Perform a first chemical mechanical polishing to remove excess filler material from the surface and flatten the circuit surface; Step S6: Place a shielding object at the preset signal acquisition electrode position for shielding treatment; Step S7: Sputter a second insulating layer in the unshielded groove structure area; Step S8: Remove the masking material and sputter an electrode layer at the masked location; and step S9: Perform a second chemical mechanical polishing to planarize the surface and form an electrode.

[0007] As a further optimized technical solution, in step S1, a nickel-titanium alloy support substrate with a grooved structure is prepared, specifically including: Step S101: Heat treat the nickel-titanium alloy tube to induce an austenitic phase transformation. Step S102: Flatten the nickel-titanium alloy tubing and fix it with adhesive. Step S103: The required groove structure is formed on the bonded nickel-titanium alloy plate material by etching process.

[0008] As a further optimized technical solution, the operation steps within the wire groove include: sputtering a first insulating layer at the bottom of the wire groove, sputtering a conductive layer on the first insulating layer, filling the groove structure above the conductive layer using a TSV (Through-Silicon Via) electroplating process to form a vertical conductive circuit layer, performing a first chemical mechanical polishing to remove excess filler material from the surface and flatten the circuit surface; and sputtering a second insulating layer in the wire groove area to finally form the wire.

[0009] As a further optimized technical solution, in step S1, a nickel-titanium alloy support substrate with a grooved structure is prepared, specifically including: The required groove structure is formed directly on the nickel-titanium alloy sheet through cutting and grooving processes.

[0010] As a further optimized technical solution, each of the electrode slots is connected to the proximal end of the support substrate through at least one wire slot.

[0011] As a further optimized technical solution, the material of the first insulating layer is SiO2.

[0012] As a further optimized technical solution, the conductive layer is made of Cu, Ag, or Pt.

[0013] As a further optimized technical solution, the electrode layer is made of Pt.

[0014] As a further optimized technical solution, in step S6, the shielding object is an insulating pillar, and the height of the insulating pillar is greater than the thickness of the second insulating layer.

[0015] Another object of the present invention is to provide an interventional brain-computer interface scaffold prepared by the above method, the specific design of which is as follows: The interventional brain-computer interface scaffold is prepared by any one of the above technical solutions. The interventional brain-computer interface scaffold includes a nickel-titanium alloy scaffold substrate. The nickel-titanium alloy scaffold substrate has a cylindrical structure to conform to the shape of blood vessels. The nickel-titanium alloy scaffold substrate has a mesh structure. The outer surface of the mesh structure has a groove structure. A layered structure for signal acquisition and transmission is integrated within the groove structure.

[0016] The beneficial effects of the fabrication method for the interventional brain-computer interface scaffold are as follows: By sputtering an insulating layer and a conductive layer at the bottom of the electrode groove of the scaffold substrate and using a TSV electroplating filling process, a three-dimensional vertical integration of the information acquisition circuit is achieved on the interventional scaffold. The information acquisition system is firmly attached to the scaffold substrate, rather than simply assembled on the surface, avoiding the problems of insufficient assembly accuracy and unstable contact caused by the post-assembly method of the existing technology, and greatly improving the mechanical stability of the signal acquisition circuit. In addition, by combining shielding treatment with secondary sputtering of the insulating layer, the precise definition of the electrode position and the comprehensive insulation protection of the conductive layer are achieved, ensuring the uniqueness and clarity of the signal acquisition point, while avoiding signal leakage and crosstalk during transmission.

[0017] Furthermore, by performing three-dimensional vertical integration of conductive lines within the conductor groove, the reliability and efficiency of signal transmission can be guaranteed while ensuring the stability of the acquired signal.

[0018] Furthermore, by systematically applying a nickel-titanium alloy scaffold substrate, a SiO2 insulating layer, a Pt biocompatible electrode layer, and multiple chemical mechanical polishing processes, excellent biocompatibility and signal interface stability are achieved while ensuring high conductivity.

[0019] The beneficial effects of interventional brain-computer interface scaffolds are the same as those of the preparation method of interventional brain-computer interface scaffolds, and will not be elaborated here. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein: Figure 1 This is a schematic diagram of the manufacturing process of an embodiment of the method for preparing the interventional brain-computer interface scaffold of the present invention; Figure 2 This is a schematic diagram of the electrode groove and wire groove processed according to an embodiment of the preparation method of the interventional brain-computer interface scaffold of the present invention; Figure 3 This is a schematic diagram of the sputtered conductive layer in one embodiment of the preparation method of the interventional brain-computer interface scaffold of the present invention; Figure 4 This is a schematic diagram of the sputtered electrode layer in one embodiment of the preparation method of the interventional brain-computer interface scaffold of the present invention; Figure 5 This is a schematic diagram of the overall structure of one embodiment of the interventional brain-computer interface scaffold of the present invention.

[0021] In the figure: 100, support substrate; 110, first insulating layer; 120, conductive layer; 130, conductive circuit layer; 140, second insulating layer; 150, electrode layer; 151, electrode; 160, electrode groove; 170, wire groove; 200, shielding material. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0023] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances. Furthermore, the term "proximal end" uniformly refers to the end closer to the operator, while "distal end" refers to the end farther from the operator.

[0024] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0025] The shapes and sizes of the components in the accompanying drawings do not reflect the actual proportions of the product; they are only intended to illustrate the content of the invention.

[0026] This invention provides a method for fabricating an interventional brain-computer interface scaffold and the scaffold itself. The fabrication method includes: fabricating a nickel-titanium alloy scaffold substrate 100 with a grooved structure, the grooved structure including an electrode groove for integrating electrodes and a wire groove for laying wires, the electrode groove and the wire groove being connected; integrating electrodes in the electrode groove and forming wires in the wire groove. Specifically, when integrating electrodes, a first insulating layer 110 is sputtered at the bottom of the electrode groove; a conductive layer 120 is sputtered; a vertical conductive circuit layer 130 is formed by filling the groove with TSV electroplating; a first chemical mechanical polishing; after placing a shielding material 200 at the electrode position, a second insulating layer 140 is sputtered; the shielding material is removed and an electrode layer 150 is sputtered; a second chemical mechanical polishing is performed to form electrodes. Specifically, when integrating wires, a first insulating layer 110 is sputtered at the bottom of the wire groove 170, a conductive layer 120 is sputtered on the first insulating layer 110, and a TSV (Through-Silicon) electroplating is performed above the conductive layer 120. (a) An electroplating process is used to fill the grooved structure, forming a vertically oriented conductive circuit layer 130. A first chemical mechanical polishing is then performed to remove excess filler material and planarize the circuit surface. A second insulating layer 140 is sputtered into the wire groove 170 region to finally form the wire. This invention, by adjusting the processing technology, achieves integrated conductive circuitry and electrodes within the scaffold substrate 100, replacing the traditional post-assembly method and significantly improving the stability and reliability of signal transmission. Simultaneously, this invention also provides an interventional brain-computer interface scaffold prepared by this method. This scaffold has a cylindrical structure and an integrated layered structure for signal acquisition and transmission, exhibiting good vascular adhesion and biocompatibility.

[0027] Example 1 of a method for fabricating an interventional brain-computer interface scaffold like Figure 1 As shown, the method for fabricating an interventional brain-computer interface scaffold includes the following steps: Step S1: Provide a nickel-titanium alloy plate. Using ultraviolet lithography and reactive ion etching (or an ultrafast laser processing system), cut a mesh support structure on the plate, and etch grooves on the outer surface of the mesh wires. These grooves include electrode grooves 160 for integrating electrodes and wire grooves 170 for routing wires. The electrode grooves 160 and wire grooves 170 are connected. In this embodiment, each electrode groove 160 is connected to the proximal end of the support substrate 100 through at least one wire groove 170. (See reference [link to documentation] for details.) Figure 2 .

[0028] Step S2: Place the grooved substrate into a magnetron sputtering apparatus and use SiO2 as the target material to sputter a dense SiO2 thin film with a thickness of about 200-300 nm on the bottom and sidewalls of the electrode groove 160 and the wire groove 170 as the first insulating layer 110.

[0029] Step S3: Inside the magnetron sputtering equipment, switch the material to Cu, Ag, or Pt, and sputter a thin film with a thickness of approximately 200-300 nm onto the first insulating layer 110 as the conductive layer 120. (See details in [link to documentation]). Figure 3 .

[0030] Step S4: The support substrate 100 is used as the cathode for TSV (TSVThrough-Silicon Via) electroplating and the grooves are filled to form a solid, vertically oriented conductive circuit layer 130.

[0031] Step S5: Perform a first chemical mechanical polishing (CMP) on the electrode groove 160 and the wire groove 170 to remove excess filler material from the surface and flatten the circuit surface to make it flush with the surface of the support substrate 100.

[0032] Step S6: A shielding material 200 is placed at the center of each electrode groove 160 for shielding treatment. The shielding material 200 can be temporarily fixed by adhesive bonding. The shielding material 200 is an insulating column made of SiO2 material, and the height of the insulating column is 0.5-0.75mm, which is greater than the thickness of the second insulating layer 140.

[0033] Step S7: A dense SiO2 film with a thickness of about 200-300 nm is sputtered in the unshielded electrode groove 160 and wire groove 170 regions as a second insulating layer 140.

[0034] Step S8: Remove the shielding material 200 and sputter a Pt electrode layer 150 at the shielded location. (See details in the original text.) Figure 4 And in step S9, a second chemical mechanical polishing (CMP) is performed to planarize the surface, remove excess Pt around the masking location, so that the electrode layer 150 is flush with the second insulating layer 140 and precisely at the masking location to form the electrode 151.

[0035] The interventional brain-computer interface scaffold prepared by the above process, after its nickel-titanium alloy scaffold substrate 100 is subsequently rolled and shaped, forms a cylindrical mesh structure, which can be successfully implanted through vascular intervention.

[0036] In the above preparation method, the layered structure system achieves substrate insulation through the first insulating layer 110. Because the nickel-titanium alloy scaffold substrate 100 is a metallic material with conductivity, and the conductive layer 120 is specifically designed to transmit the EEG signals collected by the electrode 151, direct contact between the two could easily cause current shunting between the substrate and the conductive layer 120, leading to signal attenuation or distortion. The high insulation of the first insulating layer 110 completely cuts off this pathway, ensuring that the conductive layer 120 only transmits the target EEG signal. In this embodiment, the conductive layer 120 is made of Cu, Ag, or Pt. Low-impedance signal transmission is achieved through the conductive circuit layer 130, circuit protection is achieved through the second insulating layer 140, and excellent biocompatibility and a stable electrochemical interface are achieved through the Pt electrode layer 150. The bracket processed by this method realizes three-dimensional vertical integration of conductive circuits. The information acquisition and transmission circuit system is firmly attached to the bracket substrate 100, rather than simply assembled on the surface. This avoids the technical problems of insufficient assembly accuracy and unstable contact caused by the post-assembly method of the prior art, and greatly improves the mechanical stability of the circuit and the reliability and efficiency of signal transmission.

[0037] Example 2 of a method for fabricating an interventional brain-computer interface scaffold The difference between this embodiment and Embodiment 1 lies only in the method for preparing the nickel-titanium alloy scaffold substrate 100 with a grooved structure. In this embodiment, step S1, preparing the nickel-titanium alloy scaffold substrate 100 with a grooved structure, specifically includes the following steps: Step S101: Heat treat the nickel-titanium alloy tube to induce an austenitic phase transformation. Step S102: Flatten the nickel-titanium alloy tube and bond it to the processing base. Step S103: The required groove structure is formed on the bonded nickel-titanium alloy plate material by etching process.

[0038] After obtaining the stent substrate 100, the subsequent steps S2 to S9 are completely consistent with those in Example 1, and will not be repeated here. The final stent substrate 100 is also subsequently rolled and shaped to form a cylindrical mesh structure, thereby ensuring implantation via vascular intervention.

[0039] Example 1 of an interventional brain-computer interface scaffold like Figure 5As shown, an interventional brain-computer interface scaffold is prepared by the method of any of the above embodiments. The interventional brain-computer interface scaffold includes a nickel-titanium alloy scaffold substrate 100. The nickel-titanium alloy scaffold substrate 100 has a cylindrical structure to conform to the shape of blood vessels. The nickel-titanium alloy scaffold substrate 100 has a mesh structure. The mesh structure design ensures mechanical support performance and has good flexibility and biocompatibility. The outer surface of the mesh structure has a groove structure. A layered structure for signal acquisition and transmission is integrated in the groove structure.

[0040] The layered structure includes, from bottom to top, a first insulating layer 110, a conductive layer 120, and a conductive circuit layer 130 within the electrode groove 160. An electrode layer 150 is provided at the preset electrode position, and a second insulating layer 140 covers the non-electrode area. Within the wire groove 170, the structure includes, from bottom to top, a first insulating layer 110, a conductive layer 120, a conductive circuit layer 130, and a second insulating layer 140. In this way, the bracket as a whole achieves a high degree of integration between signal acquisition and conduction functions and the bracket structure.

[0041] In summary, the method for fabricating an interventional brain-computer interface scaffold provided by this invention combines microelectronic technology with innovative biomanufacturing. The steps are clear and the parameters are controllable, providing a solid technical foundation for the large-scale and standardized production of interventional brain-computer interface scaffolds. The scaffolds prepared by this method have excellent mechanical properties, stable electrical properties, and long-term biocompatibility, providing a reliable hardware solution for the clinical translation of brain-computer interface technology.

[0042] It is understood that the above description is merely exemplary and the embodiments of this application do not limit the scope of the application.

[0043] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are within the protection scope of the present invention.

Claims

1. A method for preparing an interventional brain-computer interface scaffold, characterized in that, Includes the following steps: Step S1: Prepare a nickel-titanium alloy support substrate (100) with a grooved structure. The grooved structure includes an electrode groove (160) for integrating electrodes and a wire groove (170) for laying wires. The electrode groove (160) and the wire groove (170) are connected. Step S2, a first insulating layer (110) is sputtered at the bottom of the electrode groove (160). Step S3: Sputter a conductive layer (120) onto the first insulating layer (110). Step S4: Fill the groove structure above the conductive layer (120) using TSV (Through-Silicon Via) electroplating process to form a vertical conductive circuit layer (130). Step S5: Perform a first chemical mechanical polishing to remove excess filler material from the surface and flatten the circuit surface; Step S6: Place a shield (200) at the preset signal acquisition electrode position for shielding treatment; Step S7: Sputter a second insulating layer (140) in the unshielded groove structure area. Step S8: Remove the shielding material (200) and sputter an electrode layer (150) at the shielded location. And in step S9, a second chemical mechanical polishing is performed to planarize the surface and form an electrode.

2. The method for preparing the interventional brain-computer interface scaffold according to claim 1, characterized in that, The operation steps within the wire groove (170) include: sputtering a first insulating layer (110) at the bottom of the wire groove (170); sputtering a conductive layer (120) on the first insulating layer (110); filling the groove structure above the conductive layer (120) using a TSV (Through-Silicon Via) electroplating process to form a vertical conductive circuit layer (130); performing a first chemical mechanical polishing to remove excess filler material from the surface and planarize the circuit surface; and sputtering a second insulating layer (140) in the area of ​​the wire groove (170) to finally form the wire.

3. The method for preparing the interventional brain-computer interface scaffold according to claim 1, characterized in that, In step S1, a nickel-titanium alloy support substrate (100) with a grooved structure is prepared, specifically including: Step S101: Heat treat the nickel-titanium alloy tube to induce an austenitic phase transformation. Step S102: Flatten the nickel-titanium alloy tubing and fix it with adhesive. Step S103: The required groove structure is formed on the bonded nickel-titanium alloy plate material by etching process.

4. The method for preparing the interventional brain-computer interface scaffold according to claim 1, characterized in that, In step S1, a nickel-titanium alloy support substrate (100) with a grooved structure is prepared, specifically including: The required groove structure is formed directly on the nickel-titanium alloy sheet through cutting and grooving processes.

5. The method for preparing the interventional brain-computer interface scaffold according to claim 1, characterized in that, Each of the electrode slots (160) is connected to the proximal end of the support base (100) via at least one wire slot (170).

6. The method for preparing the interventional brain-computer interface scaffold according to claim 1 or 2, characterized in that, The first insulating layer (110) is made of SiO2.

7. The method for preparing the interventional brain-computer interface scaffold according to claim 1 or 2, characterized in that, The conductive layer (120) is made of Cu, Ag, or Pt.

8. The method for preparing the interventional brain-computer interface scaffold according to claim 1 or 2, characterized in that, The electrode layer (150) is made of Pt.

9. The method for preparing the interventional brain-computer interface scaffold according to claim 1 or 2, characterized in that, In step S6, the shield (200) is an insulating pillar, the height of which is greater than the thickness of the second insulating layer (140).

10. An interventional brain-computer interface scaffold, characterized in that, The interventional brain-computer interface scaffold is prepared by the method of any one of claims 1 to 9. The interventional brain-computer interface scaffold includes a nickel-titanium alloy scaffold substrate (100). The nickel-titanium alloy scaffold substrate (100) has a cylindrical structure to conform to the shape of blood vessels. The nickel-titanium alloy scaffold substrate (100) has a mesh structure. The outer surface of the mesh structure has a groove structure. A layered structure for signal acquisition and transmission is integrated in the groove structure.

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