Application method of flexible electrode array

Abstract

The invention discloses a use method of a flexible electrode array, and relates to the field of artificial intelligence. Comprising the following step: soaking a plurality of flexible electrodes of a flexible electrode array in liquid nitrogen for use. Due to the fact that the materials, making contact with an implanted object, of the flexible electrodes of the flexible electrode array are flexible materials, the implantation pressure is insufficient during implantation, and a large wound is likely to be caused, in order to improve the implantation strength of the flexible electrodes, the flexible electrodes are subjected to liquid nitrogen treatment before implantation, the hardness of the flexible electrodes during implantation is increased, and the implantation strength of the flexible electrodes is improved. After implantation, the flexible electrode recovers to a flexible state based on the heat effect, so that damage to an implanted object caused by the rigid electrode when the implanted object is implanted is reduced. Meanwhile, the liquid nitrogen implantation mode has higher implantation efficiency, the implantation operation process is simplified, the dependence on auxiliary equipment such as a surgical robot is reduced, and the operation complexity and cost are reduced. An implantation tool and method easy to operate are designed, so that a doctor can implant an electrode into a target area quickly and accurately.

Description

Technical Field

[0001] The present application relates to the field of artificial intelligence technology, and in particular to a flexible electrode array and a method for using the same, and a brain-computer interface device. Background Art

[0002] Currently, most invasive electrode structures are rigid structures, such as the Michigan electrode and the Utah electrode. The implantation of rigid electrodes will cause damage to the implanted object, thereby increasing the foreign body rejection reaction of the implanted object.

[0003] However, flexible electrodes usually lack sufficient implant strength and have high implant resistance. Summary of the invention

[0004] The present application provides a method for using a flexible microelectrode array to solve the problem that existing flexible electrodes generally have insufficient implantation strength and large implantation resistance.

[0005] In a first aspect, the present application provides a method for using a flexible electrode array, comprising the following steps:

[0006] The multiple flexible electrodes of the flexible electrode array are soaked in liquid nitrogen before use.

[0007] Since the material that the flexible electrode of the flexible electrode array contacts with the implant is a flexible material, the implantation pressure is insufficient during implantation, which can easily lead to a large wound. In order to improve the implantation strength of the flexible electrode, the flexible electrode is treated with liquid nitrogen before implantation to increase the hardness of the flexible electrode during implantation. After implantation, the flexible electrode returns to a flexible state based on the thermal effect, reducing the damage caused by the rigid electrode to the implant when implanted. At the same time, the liquid nitrogen implantation method has higher implantation efficiency, simplifies the implantation surgery process, reduces dependence on auxiliary equipment such as surgical robots, and reduces the complexity and cost of the surgery. Design easy-to-operate implantation tools and methods so that doctors can quickly and accurately implant electrodes into the target area.

[0008] It should be noted that the implant may be animal tissue, such as brain tissue or muscle tissue.

[0009] In some embodiments, the soaking time is 0.5 to 15 minutes. When the soaking time is within this range, the implantation strength of the flexible electrode can be improved, the implantation efficiency can be higher, the implantation surgery process can be simplified, the dependence on auxiliary equipment such as surgical robots can be reduced, and the complexity and cost of the surgery can be reduced.

[0010] In some embodiments, the flexible electrode is used within 5 minutes after soaking. Using the flexible electrode within 5 minutes after soaking can reduce the degree of change from hard to soft, improve the implantation strength of the flexible electrode, and reduce the implantation resistance.

[0011] In some embodiments, the step of soaking the plurality of flexible electrodes of the flexible electrode array in liquid nitrogen before use further comprises:

[0012] The flexible electrodes of the flexible electrode array are soaked in physiological saline. Soaking in physiological saline can clean impurities on the surface of the flexible electrodes and reduce contamination.

[0013] In some embodiments, the step of soaking the plurality of flexible electrodes of the flexible electrode array in liquid nitrogen and then using the plurality of flexible electrodes further comprises:

[0014] Collect raw data of brain nerves;

[0015] The raw data of brain nerves is processed by the internal processing chip to obtain the first pre-processed data;

[0016] The first preprocessed data is processed again by the internal processor to obtain the second preprocessed data;

[0017] The second pre-processed data is wirelessly transmitted to an external processor for processing.

[0018] By processing the raw data of brain nerves through an internal processing chip to obtain the first preprocessed data, the first preprocessed data is processed again by the internal processor to obtain the second preprocessed data, and the second preprocessed data is wirelessly transmitted to an external processor for processing, the data collected by the electrodes can be preprocessed on-site to reduce transmission loss and noise signals, and improve the accuracy of data transmission. Especially for a large number of electrode arrays, that is, high-throughput electrode arrays, since the amount of collected data is very large, directly transmitting the data collected by the electrodes to the external processor has a large transmission pressure and a lot of noise. By preprocessing the electrode collection signal through the internal processor, the amount of data that needs to be transmitted to the external processor after preprocessing is greatly reduced, which can reduce the pressure of data transmission and improve processing efficiency.

[0019] In some embodiments, the flexible electrode array includes a plurality of electrode assemblies arranged at intervals, and the electrode assemblies include:

[0020] an electrode support layer, comprising a first flexible layer and a wire layer arranged in sequence; and

[0021] A plurality of flexible electrodes arranged at intervals, wherein the flexible electrodes include a second flexible layer and an electrode, wherein at least a portion of the electrode is exposed from the second flexible layer, the second flexible layer is connected to the first flexible layer, and the electrode is in communication connection with the wire layer;

[0022] Among them, at least two flexible electrodes have different lengths.

[0023] In the present application, the flexible electrode includes a second flexible layer and an electrode, wherein the electrode is at least partially exposed in the second flexible layer, and the second flexible layer contacts the implantation site, has a low hardness, can reduce continuous strain and repeated damage, and reduce the probability of increased local inflammation and more serious foreign body rejection reactions. The electrode can improve the accuracy of signal transmission and reduce noise. Since the shape of the implant is not a planar structure, but is composed of different curvatures, when the flexible electrode is implanted in the implant, the pressure of each electrode in contact with the implant is not the same. When the flexible electrode is set to have at least two flexible electrodes of different lengths, the length of the flexible electrode during implantation can be adjusted according to the curved shape of the implant at the implantation site, so that when implanted, the pressure of multiple flexible electrodes in contact with the implant is released in sequence, which matches the compliance of the implant more highly, is less traumatic, less invasive, improves the implantation strength, reduces the implantation resistance, and reduces the implantation damage.

[0024] It should be noted that at least two flexible electrodes have different lengths. In some embodiments, the electrodes may be arranged in a manner that decreases in height from left to right; in some embodiments, the flexible electrodes may be arranged in a manner that increases in height from left to right; in some embodiments, the flexible electrodes may be arranged in a manner that increases in height from the edge to the center; in some embodiments, the flexible electrodes may be arranged in a manner that decreases in height from the edge to the center. The selection can be made according to the specific usage scenario.

[0025] It should be noted that the flexible electrode is a needle-like structure, and its extension direction is in the same plane as the electrode support layer, forming a comb-like structure.

[0026] It should be noted that at least part of the electrode is exposed to the second flexible layer. In some embodiments, the tip of the electrode may be exposed to the second flexible layer, and the rest of the electrode may be covered in the second flexible layer. In some embodiments, the electrode may be exposed to the second flexible layer in a spaced manner at multiple points in the length direction to form spaced electrode contacts. This exposure of the electrode contacts can improve the signal acquisition sensitivity and signal acquisition amount compared to the exposure of the tip of the electrode to the second flexible layer.

[0027] In some embodiments, among the plurality of spaced flexible electrodes, the length of the electrode in the middle is greater than the length of the electrodes on both sides. When implanted, the length of the electrode in the middle is greater than the length of the electrodes on both sides so that the electrode in the middle contacts the implanted object first, the resistance of the implant is small, and the implantation is easier. The entire electrode array presents a conical structure, which has less resistance during implantation, reducing invasiveness and wounds.

[0028] In some embodiments, among the plurality of flexible electrodes arranged at intervals:

[0029] The spacing between the flexible electrodes is 0.3 to 1 mm. Within this range, the spacing between the flexible electrodes can reduce implantation resistance and damage; and / or,

[0030] The length of the flexible electrode is 3.5 to 10 mm. When the length of the flexible electrode is within this range, the sensitivity of brain signal acquisition can be improved while the implantation strength can be improved; and / or,

[0031] The number of flexible electrodes in the flexible electrode array is 1024 to 16384. Within this range, the data throughput and the accuracy of the collected data can be increased. The number of flexible electrodes in a single electrode assembly can be 16, 32 or 64.

[0032] The flexible electrode may be rectangular or circular, with the size of the rectangle being (20-50)*(30-70) μm and the diameter of the circle being 20-100 μm.

[0033] In some embodiments, the electrode assembly further includes an internal processing chip, which is electrically connected to the plurality of spaced-apart flexible electrodes, and is used to pre-process brain signals collected by the plurality of spaced-apart flexible electrodes, and transmit the pre-processed signals to other processors. This can achieve real-time, rapid, and accurate extraction of brain signals, minimize noise signals of collected signals, and achieve stable and lossless signal transmission.

[0034] In some embodiments, the wire layer includes a plurality of wires and a plurality of first contacts, the plurality of wires are buried in the first flexible layer, the plurality of first contacts are disposed on the surface of the first flexible layer, and the internal processing chip includes a plurality of second contacts, wherein:

[0035] One end of the plurality of wires is respectively connected to the plurality of electrodes arranged at intervals, and the other end is respectively connected to the plurality of first contacts;

[0036] The plurality of first contacts are respectively communicatively connected with the plurality of second contacts of the internal processing chips.

[0037] It should be noted that in order to provide sufficient support for the electrode support layer, the electrode support layer also includes a 200-250 μm Si material substrate structure to support the flexible material, so that the electrode support layer can withstand the implantation pressure when implanted, and is connected to the flexible coating layer of the outer layer of the electrode through the first flexible layer, thereby realizing the fixation of the electrode support layer and the flexible electrode, and connecting one end of the plurality of wires to the plurality of electrodes arranged at intervals, and the other end to the plurality of first contacts, respectively, to realize electrode signal transmission, and transmit the brain signal collected by the electrode to the internal processing chip through the communication connection between the first contact and the internal processing chip. The data collected by the electrode can be preprocessed by the internal processing chip to reduce transmission loss and noise signals, and improve the accuracy of data transmission. In particular, for a large number of electrode arrays, that is, high-throughput electrode arrays, since the amount of collected data is very large, the transmission pressure of directly transmitting the data collected by the electrode to other processors is large and the noise is high. By preprocessing the electrode collection signal through the internal processing chip, the amount of data that needs to be transmitted to other processors after preprocessing is greatly reduced, which can reduce the pressure of data transmission and improve processing efficiency.

[0038] It should be noted that each metal wire is connected to a corresponding first contact point, so that the data collected by each electrode can be transmitted independently, thereby improving the accuracy of the data.

[0039] Typically, the internal processing chip can be a CMOS circuit chip, which is packaged by welding the second contact electrode of the CMOS circuit chip to the first contact on the electrode support layer through the inverted solder joint array, leaving only the flexible electrode exposed to contact the implant.

[0040] In some embodiments, the flexible electrode array further comprises an internal processor, wherein the internal processor is used to receive the signal preprocessed by the internal processing chip and preprocess the preprocessed signal again. 通过 Re-preprocessing the preprocessed signal can further reduce the noise signal of the collected signal and achieve stable and lossless signal transmission.

[0041] In some embodiments, the internal processor includes a communication module, and the communication module includes a charging circuit, a data processing circuit, a wireless communication chip, a power management chip, a microstrip line connector and a charging coil connected in communication, wherein the microstrip line connector is connected in communication with the internal processing chip. After the inverted solder array of the CMOS circuit, i.e., the second contact, is welded to the first contact on the electrode support layer, the inverted solder point of the CMOS microstrip line, i.e., the third contact, is connected to the microstrip line inverted soldering to communicate with the internal processor. The data processing circuit can pre-process the data collected by the electrode, reduce the data output, remove noise data, and reduce the pressure of data transmission. The wireless communication chip can realize the real-time, fast and accurate export of neural signals to minimize transmission loss and noise signals. The microstrip line connector can realize data transmission between the internal processor and the internal processing chip, and the microstrip line connector can be connected to the third contact through the microstrip line to realize the connection between the internal processor and the internal processing chip. The present application does not limit the specific positions of the charging circuit, the data processing circuit, the wireless communication chip, the power management chip, the microstrip line connector and the charging coil, and the wiring and position arrangement can be carried out according to the actual situation.

[0042] It should be noted that the number of second contacts of the internal processing chip corresponds one-to-one to the number of first contacts, so the number is relatively large. The internal processing chip converts brain signals from electrical signals to digital signals, and can perform simple filtering and noise filtering, while amplifying the brain signals. Therefore, the number of third contacts of the internal processing chip is greatly reduced compared to the number of second contacts.

[0043] In some embodiments, a plurality of the electrode assemblies are arranged in parallel, wherein the internal processing chip is provided with a through hole, and a connecting rod is inserted into the through holes of two adjacent internal processing chips. Since a plurality of the electrode assemblies are arranged in parallel to form a flexible electrode array, it is necessary to ensure that the entire flexible electrode array is fixed in position and does not move during implantation, so each electrode assembly needs to be fixed, that is, the single-piece electrode assembly is combined into a whole, and a through hole is provided on the internal processing chip, and a connecting rod is inserted into the through holes of two adjacent internal processing chips, and a plurality of electrode assemblies can be fixed by positioning the connecting rod and the through hole, which is convenient for implantation, reduces implantation pressure, and is convenient for packaging the electrode assembly.

[0044] It should be noted that in order to further reduce the movement of the electrode assembly, after the multiple electrode assemblies are fixed through the connecting rod through holes, a shell can be packaged on the periphery of the electrode support layer to further fix the electrode assembly and improve the reliability of implantation.

[0045] In some embodiments, the distance between two adjacent electrode assemblies is 0.3-1 mm. The distance between two adjacent electrode assemblies within this range can reduce implantation resistance and implantation trauma; and / or,

[0046] The thickness of the first flexible layer is 25-50 μm. The thickness of the first flexible layer within this range can improve the coagulation firmness between the electrode support layer and the electrode, reduce the occurrence of electrode breakage, and improve implantation strength.

[0047] In some embodiments, the material of the first flexible layer includes at least one of PI, PDMS and silicone resin, PI refers to benzocyclobutane, PDMS refers to polydimethylsiloxane, and the use of the above materials can improve the biocompatibility of the flexible array, reduce rejection reactions after implantation, and reduce damage to the implanted object; and / or,

[0048] The material of the wire layer includes at least one of gold, platinum, iridium, tungsten, magnesium, molybdenum, platinum-iridium alloy, titanium alloy, graphite, and carbon nanotubes. The use of the above wire layer materials can improve the accuracy of data transmission; and / or,

[0049] The material of the second flexible layer includes at least one of PI, PDMS and silicone resin. The use of the above materials can improve the biocompatibility of the second flexible layer, reduce rejection reactions after implantation, and reduce damage to the implanted object; and / or,

[0050] The material of the electrode includes at least one of gold, platinum, iridium, tungsten, magnesium, molybdenum, platinum-iridium alloy, titanium alloy, graphite, and carbon nanotubes. The use of the above electrode materials can improve the sensitivity of the electrode in collecting data and improve the accuracy of the data.

[0051] In some embodiments, the flexible electrode array can be prepared by the following preparation method:

[0052] Prepare an oxide layer on the surface of the silicon wafer as a dielectric layer;

[0053] Prepare a first flexible layer material on the surface of the silicon wafer with a thickness of 30 μm to ensure implantation strength;

[0054] Depositing metal on the surface of the first flexible layer and patterning the deposited metal into metal leads;

[0055] A first flexible layer material is prepared on the metal surface to encapsulate the metal lead, and then photoresist, photolithography, and development are performed to prepare the cavity opening by etching;

[0056] Depositing electrode material at the cavity opening and obtaining contact electrodes by stripping;

[0057] Depositing indium metal in the cavity on the electrode support layer to form a plurality of first contacts;

[0058] Release the electrode assembly from the silicon substrate. The release process can be mechanical, physical or chemical, wherein the silicon wafer behind the electrode support layer is not peeled off, only the electrode is peeled off;

[0059] The electrode assembly is welded to the CMOS circuit via the first contact, and multiple electrode assemblies are connected and fixed via connecting rods through through holes etched or laser cut on the electrode support layer, and then packaged in a packaging shell to form a flexible electrode array. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0061] Figure 1 Flow chart of a method for using a flexible electrode array according to an embodiment of the present application.

[0062] Figure 2 It is a schematic diagram of the structure of the electrode assembly of the flexible electrode array in the method for using the flexible electrode array according to one embodiment of the present application.

[0063] Figure 3 It is a schematic diagram of the structure of the electrode assembly of the flexible electrode array in the method for using the flexible electrode array according to one embodiment of the present application.

[0064] Figure 4 It is a schematic diagram of the structure of the electrode assembly of the flexible electrode array in the method for using the flexible electrode array according to one embodiment of the present application.

[0065] Figure 5 It is a schematic diagram of the structure of the electrode assembly of the flexible electrode array in the method for using the flexible electrode array according to one embodiment of the present application.

[0066] Figure 6 It is a cross-sectional view of an electrode assembly of a flexible electrode array in a method for using a flexible electrode array according to an embodiment of the present application.

[0067] Figure 7 It is a structural exploded diagram of a flexible electrode array in a method for using a flexible electrode array according to an embodiment of the present application.

[0068] Figure 8 Schematic diagram of the internal processing chip structure of the flexible electrode array in the method for using the flexible electrode array according to one embodiment of the present application.

[0069] Description of Figure Numbers:

[0070] 100 flexible electrode array; 10 electrode assembly; 1 electrode support layer; 11 first flexible layer; 12 wire layer; 121 wire; 122 first contact; 2 flexible electrode; 21 second flexible layer; 22 electrode; 3 internal processor; 31 communication module; 311 charging circuit; 312 data processing circuit; 313 wireless communication chip; 314 power management chip; 315 microstrip line connector; 316 charging coil; 4 internal processing chip; 32 microstrip line; 41 second contact; 42 third contact; 43 through hole; 44 connecting rod; 5 outer shell. DETAILED DESCRIPTION

[0071] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0072] Currently, most invasive electrode structures are rigid structures, such as the Michigan electrode and the Utah electrode. The implantation of rigid electrodes will cause damage to the implanted object, thereby increasing the foreign body rejection reaction of the implanted object.

[0073] Direct electrical recording and stimulation of neural activity based on existing rigid electrodes such as silicon-based and metal microwires have made extensive contributions to basic neuroscience and therapeutic applications. However, the mismatch between the mechanical properties of these rigid electrodes and the brain is a key factor in the increased pressure at the bio-abiotic interface of the implant, especially for long-term implanted neural electrodes, which can cause great damage to the implant. In addition, due to periodic micro-motions of the brain caused by physiological and behavioral sources, the use of rigid electrode arrays in contact with soft implants causes continuous strain and repeated damage, ultimately leading to increased local inflammation and more severe foreign body rejection reactions. The movement of fixed rigid electrodes can induce shear stress and cause tissue scarring, thereby compromising the stability of recorded signals on a time scale of weeks to months.

[0074] However, flexible electrodes usually have insufficient implantation strength and high implantation resistance, and are prone to displacement during long-term implantation, which in turn affects the accuracy of data transmission.

[0075] In view of this, the present application provides a method for using a flexible microelectrode array to solve the problem that existing flexible electrodes generally have insufficient implantation strength and large implantation resistance.

[0076] First, as Figure 1 As shown, the present application provides a method for using a flexible electrode array, comprising the following steps:

[0077] The multiple flexible electrodes of the flexible electrode array are soaked in liquid nitrogen before use.

[0078] Since the material that the flexible electrode of the flexible electrode array contacts with the implant is a flexible material, the implantation pressure is insufficient during implantation, which can easily lead to a large wound. In order to improve the implantation strength of the flexible electrode, the flexible electrode is treated with liquid nitrogen before implantation to increase the hardness of the flexible electrode during implantation. After implantation, the flexible electrode returns to a flexible state based on the thermal effect, reducing the damage caused by the rigid electrode to the implant when implanted. At the same time, the liquid nitrogen implantation method has higher implantation efficiency, simplifies the implantation surgery process, reduces dependence on auxiliary equipment such as surgical robots, and reduces the complexity and cost of the surgery. Design easy-to-operate implantation tools and methods so that doctors can quickly and accurately implant electrodes into the target area.

[0079] It should be noted that the implant may be animal tissue, such as brain tissue or muscle tissue.

[0080] In combination with the first aspect, in some embodiments provided in the present application, the soaking time is 0.5 to 15 minutes. When the soaking time is within this range, the implantation strength of the flexible electrode can be improved, the implantation efficiency can be higher, the implantation surgery process can be simplified, the dependence on auxiliary equipment such as surgical robots can be reduced, and the complexity and cost of the surgery can be reduced.

[0081] In combination with the first aspect, in some embodiments provided in the present application, the flexible electrode is used within 5 minutes after soaking, which can reduce the degree of change from hard to soft of the flexible electrode, improve the implantation strength of the flexible electrode, and reduce the implantation resistance.

[0082] In combination with the first aspect, in some embodiments provided in the present application, the step of soaking the plurality of flexible electrodes of the flexible electrode array in liquid nitrogen before use further comprises:

[0083] The flexible electrodes of the flexible electrode array are soaked in physiological saline. Soaking in physiological saline can clean impurities on the surface of the flexible electrodes and reduce contamination.

[0084] In combination with the first aspect, in some embodiments provided in the present application, the method further comprises:

[0085] Collect raw data of brain nerves;

[0086] The raw data of brain nerves is processed by the internal processing chip to obtain the first pre-processed data;

[0087] The first preprocessed data is processed again by the internal processor to obtain the second preprocessed data;

[0088] The second pre-processed data is wirelessly transmitted to an external processor for processing.

[0089] By processing the raw data of brain nerves through an internal processing chip to obtain the first preprocessed data, the first preprocessed data is processed again by the internal processor to obtain the second preprocessed data, and the second preprocessed data is wirelessly transmitted to an external processor for processing, the data collected by the electrodes can be preprocessed on-site to reduce transmission loss and noise signals, and improve the accuracy of data transmission. Especially for a large number of electrode arrays, that is, high-throughput electrode arrays, since the amount of collected data is very large, directly transmitting the data collected by the electrodes to the external processor has a large transmission pressure and a lot of noise. By preprocessing the electrode collection signal through the internal processor, the amount of data that needs to be transmitted to the external processor after preprocessing is greatly reduced, which can reduce the pressure of data transmission and improve processing efficiency.

[0090] Combined with the first aspect, Figures 2 to 8 As shown, in some embodiments provided in the present application, the flexible electrode array 100 includes a plurality of electrode assemblies 10 arranged at intervals, and the electrode assemblies 10 include:

[0091] The electrode support layer 1 comprises a first flexible layer 11 and a wire layer 12 arranged in sequence; and

[0092] A plurality of flexible electrodes 2 arranged at intervals, the flexible electrodes 2 comprising a second flexible layer 21 and an electrode 22, the electrode 22 being at least partially exposed from the second flexible layer 21, the second flexible layer 21 being connected to the first flexible layer 11, and the electrode 22 being communicatively connected to the wire layer 12;

[0093] Among them, at least two flexible electrodes 2 have different lengths.

[0094] In the present application, the flexible electrode 2 includes a second flexible layer 21 and an electrode 22, wherein the electrode 22 is at least partially exposed in the second flexible layer 21, and the second flexible layer 21 contacts the implantation site, has a low hardness, can reduce continuous strain and repeated damage, and reduce the probability of increased local inflammation and more serious foreign body rejection reactions. The electrode 22 can improve the accuracy of signal transmission and reduce noise. Since the shape of the implant is not a planar structure, but is composed of different arcs, when the flexible electrode 2 is implanted in the implant, the pressure of each electrode 22 in contact with the implant is not the same. When the flexible electrode 2 is set to have at least two flexible electrodes 2 with different lengths, the length of the flexible electrode 2 during implantation can be adjusted according to the curved shape of the implant at the implantation site, so that when implanted, the pressure of multiple flexible electrodes 2 in contact with the implant is released in sequence, and the compliance of the implant is higher, the trauma is less, the invasiveness is less, the implantation strength is improved, the implantation resistance is reduced, and the implantation damage is reduced.

[0095] It should be noted that at least two flexible electrodes 2 have different lengths. In some embodiments, the flexible electrodes 2 may be arranged in a manner that decreases in height from left to right; in some embodiments, the flexible electrodes 2 may be arranged in a manner that increases in height from left to right; in some embodiments, the flexible electrodes 2 may be arranged in a manner that increases in height from the edge to the center; in some embodiments, the flexible electrodes 2 may be arranged in a manner that decreases in height from the edge to the center. The selection can be made according to the specific usage scenario.

[0096] It should be noted that the flexible electrode 2 is a needle-like structure, and its extension direction is in the same plane as the electrode support layer 1, forming a comb-like structure.

[0097] It should be noted that at least part of the electrode 22 is exposed on the second flexible layer 21. In some embodiments, the tip of the electrode 22 may be exposed on the second flexible layer 21, and the rest of the electrode 22 may be covered in the second flexible layer 21. In some embodiments, the electrode 22 may be exposed on the second flexible layer 21 at intervals in the length direction at multiple points to form spaced electrode contacts. Compared with the case where the tip of the electrode 22 is exposed on the second flexible layer 21, this method of exposing the electrode contacts can improve the signal acquisition sensitivity and signal acquisition amount.

[0098] It should be noted that the material of the exposed portion of the electrode contact may be different from or the same as the material of the portion covered in the second flexible layer 21. The electrode portion covered in the second flexible layer 21 may serve as a conductor of the electrode contact and be electrically connected to other components.

[0099] In combination with the first aspect, in some embodiments provided by the present application, among the plurality of flexible electrodes 2 arranged at intervals, the length of the electrode 22 at the middle position is greater than the length of the electrodes 22 at both sides. When implanted, the length of the electrode 22 at the middle position is greater than the length of the electrodes 22 at both sides, so that the electrode 22 at the middle position can contact the implanted object first, the resistance of the plant is small, and it is easier to implant. The entire electrode 22 array presents a conical structure, which has less resistance during implantation, reducing invasiveness and wounds.

[0100] In combination with the first aspect, in some embodiments provided in the present application, among the multiple flexible electrodes 2 arranged at intervals: the spacing between the flexible electrodes 2 is 0.3 to 1 mm. The spacing between the flexible electrodes 2 is within this range, which reduces implantation resistance and reduces damage.

[0101] In combination with the first aspect, in some embodiments provided in the present application, among the multiple flexible electrodes 2 arranged at intervals, the length of the flexible electrode 2 is 3.5 to 10 mm. The length of the flexible electrode 2 being within this range can improve the sensitivity of brain signal acquisition while improving the implantation strength.

[0102] In combination with the first aspect, in some embodiments provided in the present application, the number of flexible electrodes 2 in the flexible electrode array 100 is 1024 to 16384. The number of flexible electrodes 2 within this range can improve data throughput and improve the accuracy of collected data. The number of flexible electrodes 2 in a single electrode assembly 10 can be 16, 32, or 64.

[0103] The flexible electrode 2 may be rectangular or circular, with the size of the rectangle being (20-50)*(30-70) μm and the diameter of the circle being 20-100 μm.

[0104] In combination with the first aspect, in some embodiments provided in the present application, the electrode assembly 10 further includes an internal processing chip 4, which is electrically connected to the plurality of spaced flexible electrodes 2, and is used to pre-process the brain signals collected by the plurality of spaced flexible electrodes 2, and transmit the pre-processed signals to other processors. This can achieve real-time, fast and accurate extraction of brain signals, minimize noise signals of collected signals, and achieve stable and lossless signal transmission.

[0105] In combination with the first aspect, in some embodiments provided in the present application, the wire layer 12 includes a plurality of wires 121 and a plurality of first contacts 122, the plurality of wires 121 are buried in the first flexible layer 11, the plurality of first contacts 122 are arranged on the surface of the first flexible layer 11, and the internal processing chip 4 includes a plurality of second contacts 41, wherein:

[0106] One end of the plurality of wires 121 is respectively connected to the plurality of electrodes 22 arranged at intervals, and the other end is respectively connected to the plurality of first contacts 122;

[0107] The plurality of first contacts 122 are respectively communicatively connected to the plurality of second contacts 41 of the internal processing chips 4 .

[0108] It should be noted that, in order to provide sufficient support for the electrode support layer 1, the electrode support layer 1 also includes a 200-250 μm Si material substrate structure to support the first flexible layer 11, so that the electrode support layer 1 can withstand the implantation pressure when implanted, and is connected to the second flexible layer 21 of the outer layer of the electrode 22 through the first flexible layer 11, thereby achieving the fixation of the electrode support layer 1 and the flexible electrode 2, and connecting one end of the plurality of wires 121 to the plurality of electrodes 22 arranged at intervals, and the other end to the plurality of first contacts 122, respectively, to achieve electrode signal transmission, and transmit the brain signal collected by the electrode to the internal processing chip 4 through the communication connection between the first contact 122 and the internal processing chip 4. The data collected by the electrode 22 can be preprocessed by the internal processing chip 4 to reduce transmission loss and noise signals, and improve the accuracy of data transmission. Especially for a large number of electrode arrays, that is, high-throughput electrode arrays, since the amount of collected data is very large, directly transmitting the data collected by the electrode 22 to other processors will result in high transmission pressure and noise. By preprocessing the signals collected by the electrode 22 through the internal processing chip 4, the amount of data that needs to be transmitted to other processors after preprocessing is greatly reduced, which can reduce data transmission pressure and improve processing efficiency.

[0109] It should be noted that each metal wire 121 is correspondingly connected to the first contact 122, so that the data collected by each electrode 22 can be transmitted independently, thereby improving the accuracy of the data.

[0110] Typically, the internal processing chip 4 can be a CMOS circuit chip, which is packaged by welding the second contact electrode 41 of the CMOS circuit chip to the first contact 122 on the electrode support layer 1, leaving only the flexible electrode 2 exposed to contact the implant.

[0111] In combination with the first aspect, in some embodiments provided in the present application, the flexible electrode array 100 further includes an internal processor 3, wherein the internal processor 3 is used to receive the signal preprocessed by the internal processing chip 4 and preprocess the preprocessed signal again. By preprocessing the preprocessed signal again, the noise signal of the collected signal can be further reduced to achieve stable and lossless signal transmission.

[0112] In combination with the first aspect, the internal processor 3 includes a communication module 31, and the communication module 31 includes a charging circuit 311, a data processing circuit 312, a wireless communication chip 313, a power management chip 314, a microstrip line connector 315 and a charging coil 316 connected in communication, wherein the microstrip line connector 315 is connected in communication with the internal processing chip 4. After the inverted solder array of the CMOS circuit, i.e., the second contact 41, is welded to the first contact 122 on the electrode support layer 1, the inverted soldering point of the CMOS microstrip line, i.e., the third contact 42, is inverted soldered to the microstrip line 32 to communicate with the internal processor 3. The data processing circuit 312 can pre-process the data collected by the electrode 22, reduce the data output, remove noise data, and reduce the pressure of data transmission. The wireless communication chip 313 can realize the real-time, fast and accurate export of neural signals to minimize transmission loss and noise signals. The microstrip line connector 315 can realize data transmission between the internal processor 3 and the internal processing chip 4. The microstrip line connector 315 can be connected to the third contact 42 through the microstrip line 32 to realize the connection between the internal processor 3 and the internal processing chip 4. The present application does not limit the specific positions of the charging circuit 311, the data processing circuit 312, the wireless communication chip 313, the power management chip 314, the microstrip line connector 315 and the charging coil 316, and the wiring and position arrangement can be carried out according to the actual situation.

[0113] It should be noted that the number of second contacts 41 of the internal processing chip 4 corresponds one-to-one to the number of first contacts 122, so the number of second contacts 41 is relatively large. The internal processing chip 4 converts brain signals from electrical signals into digital signals, and can perform simple filtering and noise filtering, while amplifying the brain signals. Therefore, the number of third contacts 42 of the internal processing chip 4 is greatly reduced compared to the number of second contacts 41.

[0114] In combination with the first aspect, in some embodiments provided in the present application, a plurality of electrode assemblies 10 are arranged in parallel, wherein a through hole 43 is provided on the internal processing chip 4, and a connecting rod 44 is inserted into the through holes 43 of two adjacent electrode assemblies 10. Since a plurality of electrode assemblies 10 are arranged in parallel to form a flexible electrode array 100, it is necessary to ensure that the entire flexible electrode array 100 is fixed in position and does not move during implantation, so each electrode assembly 10 needs to be fixed, that is, the single-piece electrode assembly 10 is combined into a whole, and a through hole 43 is provided on the internal processing chip 4, and a connecting rod 44 is inserted into the through holes 43 of two adjacent electrode assemblies 10, and a plurality of electrode assemblies 10 can be fixed by positioning the connecting rod 44 and the through hole 43, which is convenient for implantation, reduces implantation pressure, and facilitates packaging of the electrode assembly 10. Usually, the position of the through hole 43 on the internal processing chip 4 needs to avoid the position of the second contact 41 and the third contact 42 to reduce interference with the circuit.

[0115] It should be noted that in order to further reduce the movement of the electrode assembly 10, after the multiple electrode assemblies 10 are fixed through the connecting rod through holes, the outer shell 5 can be packaged on the periphery of the electrode support layer 1 to further fix the electrode assembly 10 and improve the reliability of implantation.

[0116] In combination with the first aspect, in some embodiments provided in the present application, the spacing between two adjacent electrode assemblies 10 is 0.3 to 1 mm. The spacing between two adjacent electrode assemblies 10 is within this range, which can reduce implantation resistance and implantation trauma.

[0117] In combination with the first aspect, in some embodiments provided in the present application, the thickness of the first flexible layer 11 is 25 to 50 μm. The thickness of the first flexible layer 11 within this range can improve the coagulation firmness between the electrode support layer 1 and the electrode 22, reduce the occurrence of electrode 22 breakage, and improve implantation strength.

[0118] In combination with the first aspect, in some embodiments provided in the present application, the material of the first flexible layer 11 includes at least one of PI, PDMS and silicone resin, PI refers to polyimide, PDMS refers to polydimethylsiloxane, and the use of the above materials can improve the biocompatibility of the flexible array, reduce rejection reactions after implantation, and reduce damage to the implanted object.

[0119] In combination with the first aspect, in some embodiments provided in the present application, the material of the wire layer 12 includes at least one of gold, platinum, iridium, tungsten, magnesium, molybdenum, platinum-iridium alloy, titanium alloy, graphite, and carbon nanotubes. The use of the above-mentioned material of the wire layer 12 can improve the accuracy of data transmission.

[0120] In combination with the first aspect, in some embodiments provided in the present application, the material of the second flexible layer 21 includes at least one of PI, PDMS and silicone resin. The use of the above materials can improve the biocompatibility of the second flexible layer 21, reduce rejection reactions after implantation, and reduce damage to the implant.

[0121] In combination with the first aspect, in some embodiments provided in the present application, the material of the electrode 22 includes at least one of gold, platinum, iridium, tungsten, magnesium, molybdenum, platinum-iridium alloy, titanium alloy, graphite, and carbon nanotubes. The use of the above-mentioned electrode 22 material can improve the sensitivity of the electrode 22 in collecting data and improve the accuracy of the data.

[0122] In some embodiments, the flexible electrode array 100 can be manufactured by the following manufacturing method:

[0123] Prepare an oxide layer on the surface of the silicon wafer as a dielectric layer;

[0124] Prepare a first flexible layer material on the surface of the silicon wafer with a thickness of 30 μm to ensure implantation strength;

[0125] Depositing metal on the surface of the first flexible layer and patterning the deposited metal into metal leads;

[0126] A first flexible layer material is prepared on the metal surface to encapsulate the metal lead, and then photoresist, photolithography, and development are performed to prepare the cavity opening by etching;

[0127] Depositing electrode material at the cavity opening and obtaining contact electrodes by stripping;

[0128] Depositing indium metal in the cavity on the electrode support layer to form a plurality of first contact electrodes;

[0129] Release the electrode assembly from the silicon substrate. The release process can be mechanical, physical or chemical, wherein the silicon wafer behind the electrode support layer is not peeled off, only the electrode is peeled off;

[0130] The electrode assembly is welded to the CMOS circuit via the first contact electrode, and multiple electrode assemblies are connected and fixed via connecting rods through through holes etched or laser cut on the electrode support layer, and then packaged in a packaging shell to form a flexible electrode array.

[0131] In summary, the flexible electrode includes a second flexible layer and an electrode, wherein at least part of the electrode is exposed in the second flexible layer, and the second flexible layer contacts the implantation site, has a low hardness, can reduce continuous strain and repeated damage, and reduce the probability of increased local inflammation and more serious foreign body rejection reactions. The electrode can improve the accuracy of signal transmission and reduce noise. Since the shape of the implant is not a planar structure, but is composed of different arcs, when the flexible electrode is implanted in the implant, the pressure of each electrode in contact with the implant is not the same. When the electrode is set to have at least two flexible electrodes of different lengths, the length of the flexible electrode during implantation can be adjusted according to the curved shape of the implant at the implantation site, so that during implantation, the pressure of multiple flexible electrodes in contact with the implant is released in sequence, which matches the compliance of the implant more highly, is less traumatic, less invasive, improves implantation strength, reduces implantation resistance, and reduces implantation damage.

[0132] In the description of this specification, the description with reference to the terms "one embodiment / method", "some embodiments / methods", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment / method or example are included in at least one embodiment / method or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment / method or example. Moreover, the specific features, structures, materials or characteristics described may be combined in a suitable manner in any one or more embodiments / methods or examples. In addition, those skilled in the art may combine and combine the different embodiments / methods or examples described in this specification and the features of the different embodiments / methods or examples, unless they are contradictory.

[0133] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0134] It should be noted that, in the present application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the sentence "comprise one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. In the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically stipulated.

[0135] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features applied for herein.

Claims

1. A method for using a flexible electrode array, characterized in that: The following steps are involved: The multiple flexible electrodes of the flexible electrode array are soaked in liquid nitrogen before use.

2. The method for using the flexible electrode array according to claim 1, characterized in that: The soaking time is 0.5 to 15 minutes.

3. The method for using the flexible electrode array according to claim 1, characterized in that: Use within 5 minutes after soaking.

4. The method for using the flexible electrode array according to claim 1, characterized in that: The method further comprises soaking the plurality of flexible electrodes of the flexible electrode array in liquid nitrogen before using the plurality of flexible electrodes: The flexible electrodes of the flexible electrode array are soaked in physiological saline.

5. The method for using the flexible electrode array according to claim 1, characterized in that: After the plurality of flexible electrodes of the flexible electrode array are soaked in liquid nitrogen and then used, the method further comprises: Collect raw data of brain nerves; The raw data of brain nerves is processed by the internal processing chip to obtain the first pre-processed data; The first preprocessed data is processed again by the internal processor to obtain the second preprocessed data; The second pre-processed data is wirelessly transmitted to an external processor for processing.

6. The method for using the flexible electrode array according to claim 1, characterized in that: The flexible electrode array includes a plurality of electrode assemblies arranged at intervals, and the electrode assemblies include: an electrode support layer, comprising a first flexible layer and a wire layer arranged in sequence; and A plurality of flexible electrodes arranged at intervals, wherein the flexible electrodes include a second flexible layer and an electrode, wherein at least a portion of the electrode is exposed from the second flexible layer, the second flexible layer is connected to the first flexible layer, and the electrode is in communication connection with the wire layer; Among them, at least two flexible electrodes have different lengths.

7. The method for using the flexible electrode array according to claim 6, characterized in that: Among the plurality of flexible electrodes arranged at intervals, the length of the electrode at the middle position is greater than the length of the electrodes at both sides.

8. The method for using the flexible electrode array according to claim 6, wherein: The spacing between the flexible electrodes is 0.3 to 1 mm; and / or, The length of the flexible electrode is 3.5 to 10 mm; and / or, The number of flexible electrodes in the flexible electrode array is 1024 to 16384.

9. The method for using the flexible electrode array according to claim 6, characterized in that: The electrode assembly also includes an internal processing chip, which is electrically connected to the multiple flexible electrodes arranged at intervals, and is used to pre-process brain signals collected by the multiple flexible electrodes arranged at intervals, and transmit the pre-processed signals to other processors.

10. The method for using the flexible electrode array according to claim 9, characterized in that: The wire layer includes a plurality of wires and a plurality of first contacts, the plurality of wires are buried in the first flexible layer, the plurality of first contacts are arranged on the surface of the first flexible layer, and the internal processing chip includes a plurality of second contacts, wherein: One end of the plurality of wires is respectively connected to the plurality of electrodes arranged at intervals, and the other end is respectively connected to the plurality of first contacts; The plurality of first contacts are respectively communicatively connected with the plurality of second contacts of the internal processing chips.

11. The method for using the flexible electrode array according to claim 10, characterized in that: The flexible electrode array further comprises an internal processor, wherein the internal processor is used to receive the signal preprocessed by the internal processing chip and preprocess the preprocessed signal again.

12. The method for using the flexible electrode array according to claim 11, characterized in that: The internal processor includes a communication module, which includes a charging circuit, a data processing circuit, a wireless communication chip, a power management chip, a microstrip line connector and a charging coil that are communicatively connected, wherein the microstrip line connector is communicatively connected to the internal processing chip.

13. The method for using the flexible electrode array according to claim 9, characterized in that: A plurality of the electrode assemblies are arranged in parallel, wherein the internal processing chip is provided with a through hole, and a connecting rod is passed through the through holes of two adjacent internal processing chips.

14. The method for using the flexible electrode array according to claim 6, wherein: The distance between two adjacent electrode assemblies is 0.3-1 mm; and / or, The thickness of the first flexible layer is 25-50 μm.

15. The method for using the flexible electrode array according to claim 6, wherein: The material of the first flexible layer includes at least one of PI, PDMS and silicone resin; and / or, The material of the conductor layer includes at least one of gold, platinum, iridium, tungsten, magnesium, molybdenum, platinum-iridium alloy, titanium alloy, graphite, and carbon nanotubes; and / or, The material of the second flexible layer includes at least one of PI, PDMS and silicone resin; and / or, The material of the electrode includes at least one of gold, platinum, iridium, tungsten, magnesium, molybdenum, platinum-iridium alloy, titanium alloy, graphite, and carbon nanotubes.

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