Nerve electrode based on porous silicon and polymer as well as preparation process and application thereof
The technical field is. The invention relates to the technical field of electrical sensors, in particular to a porous silicon and polymer-based nerve electrode and a manufacturing process and application thereof. Background technology People of thousands of people worldwide have lost some or all of the body motion due to the loss of part or all of the body motion. Wardial pain a is in a ratio of, for example, and / and is due to a major cause of neurological movement dysfunction. There are more than five hundred thousands of diseases in China and the United States, and a serious body and economic burden on patients and society are in order of more than five. For example, in the United States, and/due to spinal injuries, a direct treatment cost is up to up to 400 亿 u.s. dollar a. One of the more potential therapeutic approaches aimed at neuropathic dyskinesia is to control and acquire prosthesis or limbs of the outer end by controlling and acquiring pattern recognition of the brain and establishing a control channel of the brain and surrounding limbs in an artificial manner. At present, a research institution develops a central nervous signal for human body test based on a silicon material, and the central nervous signal acquired by Wallo/s can control artificial artificial limbs. The degree of importance to neuroscience and man-machine combining techniques worldwide is as well as that of day. In recent years, Chinese natural science based and national science and technology have been invested in recent years for the study of sciatic and artificial prostheses. This 2016 is in order 45 亿 u.s. dollar to better understand how to solve and how to solve. In Europe, a 2013 is in 100 亿 欧元 a more effective and more efficacious, more effective, more uncovering human brain function, and . A neural electrode device manufactured by a micro electromechanical system is in, and has an advantage in that the size is in and . A silicon-based neural electrode company manufactured based on a MEMS1/astride technology at present includes that in the United States. One of silicon substrate two-dimensional nerve electrodes of various lengths is manufactured on the basis of a silicon plane processing technology by a Co. and is. Is in, and is due to the body silicon and the deep etching technique and is in the order of body silicon and deep etching. A signal 100 acquisition channel is made on each of the neural probes, and then has a signal acquisition channel in each of the neural probes. These neural electrodes make a copy of a needle that 10 - 100 μm is 0.5 - 10 mm in a range 100 μm of from unit_@bankunit_@bankunit_@bankunit_@bankunit_@bankunit_@. These neural electrode probes have sufficient mechanical strength to insert in the brain tissue. After electrode implantation, after electrode implantation, due to its own respiratory and heartbeat effects, and heartbeats a is in order to create a micron level of movement between the implant electrode and the brain tissue. At the same time, a slight movement of the implant electrode after the electrode implantation is fixed below the skull and slight movement of the skull and the brain tissue also leads to the movement of the implant electrode. The Young's modulus of the silicon is about ± 170 GPa s.i. and the Young's modulus of the brain tissue is approximately 3 KPa ± a. A great difference in mechanical stiffness between the silicon electrode and the brain after relative movement produces horizontal shear forces in turn causes the brain tissue to be injured and thus causes inflammation reaction. The inflammatory response of this tissue produces a substance which increases the electrical impedance of the electrode and decreases the electrical impedance of the electrode on the electrode. In recent years, such as, is applied to a flexible neural electrode, and has been applied to that of a flexible neural electrode. The mechanical strength of these substances is in relation to that of the brain, and is of. The signal-to-noise ratio of the electrodes may be increased so as to increase the signal-to-noise ratio of electrodes due to minute movement of the electrodes. However, due to the fact that the flexible polymer neural electrode cannot be inserted directly into the brain tissue, such as, is often used for peripheral nerve electrodes. Current research groups develop an auxiliary way to implant flexible electrodes into the brain, and the attachment of soluble sugars with soluble sugars increases its implant strength. However, there are several technical problems such as, for example, the problems such as bio-compatibility and long-term stability, which impedes the application of these methods. Summary of the invention To overcome the long-term stability of the existing nerve electrode, the functional layer of the present invention is in order to overcome the following problems such as: and . To achieve the above-mentioned object, the technical solution adopted by the present invention is as follows: the following is as follows: One of the structural layers, which is composed of a porous silicon substrate and a silicon substrate, is as follows: and. The sandwich structure of the flexible polymer ora/astride flexible polymer refers to that the sidewall of the electrode material layer is disposed between the upper and lower layers of the flexible polymer. An electrical insulating layer is arranged between the substrate layer and the structural layer, such as, for example, silicon oxide or silicon nitride. The part of the neural electrode inserted into the brain tissue in part of the brain tissue is of a width smaller than that of the part of the brain tissue in which the part of the brain tissue is smaller than that outside the brain tissue. One or more of the electrodes of the electrode material are in a ratio of, for example, and/0.001 - 0 . 01 Ω ·cm. The porosity of the porous silicon substrate is in a range of about a-40% - 70%. The preparation process of the neural electrode based on the porous silicon and the polymer is in particular included in the following two processes: and. 1st , Silicon 1 nitride and lodging in the surface of 0.1 - 0.3 μm the silicon chip 2 - 4 μm are in order of=1, and. One of 2 the areas in the electrode area is formed by photolithography, and then is etched into a pattern of a porous silicon area and a silicon substrate area. A is 3 in a porous silicon region by an electrochemical method; the porosity of the porous silicon is=1, 40% - 70% and. And/4 or silicon nitride is deposited on the surface of the porous silicon and silicon substrate as an electrically insulating layer, and then deposited on the surface of the silicon wafer. The flexible 5 polymer surface in which the electrode material layer is deposited on the electrode material layer is, and then deposited on the electrode material layer, and then deposited on the electrode material layer. The remaining 6 metal is exposed on the upper flexible polymer by lithography and etching; the rest of the metal is covered by a flexible polymer; and then the remaining metal is covered by the flexible polymer. After that the 7 depth of the deep trench is greater than that of the electrode device 70 - 120 μm, and then is regrown by a photolithographic technique 100 - 150 μm. The trench width is 1 in order to define that the trench width is in the High ion-doped silicon wafer; and then, and /ajustrains a is in-between and then deposited on the silicon wafer surface. 100 - 150 μm 3 - 7 μm 0.1 - 0.3 μm 2 - 4 μm The preparation process of the preparation process of the porous silicon-2nd polymer-based neuron electrode is specifically included in the following steps: and. A functional layer of a flexible polymer and a metal is first made on a silicon substrate and is. The device and other areas are then protected with silicon nitride or silicon oxide or some other passivation layer protective devices and other areas. The deep etching channel is in a structure of. The last-step patterned porous silicon region is subjected to electrochemical corrosion of silicon to generate a porous silicon Wallantoin a. As a result of the formation of porous silicon, the silicon under the functional layer of Wallantoin is eventually corroded to form a porous silicon layer. Finally, the mechanical polishing of the back surface of the silicon wafer is in a ratio of, for example, in the required device thickness. The preparation of the neural electrode of the present invention takes as an anode and a cathode in a mixture of HFCs and ethanol in which platinum or graphite is deposited as a cathode in a mixture of HFCs and ethanol. The mechanical strength of porous silicon is adjusted by controlling the porosity of the porous silicon. The neural electrode probe based on porous silicon and polymer of the present invention may be partially inserted into the brain tissue. In the weak alkaline environment where neuroelectrode probe implantation is performed, Wallantoin a is in a weak alkaline environment of brain tissue, and is then transformed at a constant speed in a weak alkaline environment of brain tissue.2 @bankbook @bankbook @bankbook (OH) @bankbook/AIS2 @bankbook @bankbook @bankbook 'L=' and ' L'2 - @bankbook @bankbook @bankbook is in order to be. The chemical reaction process is as 1 follows: a. : @ipitation and @ipitation Si+2OHR a-R-criminal /aok + 2Hemeris + 2Hor/aok2 @bankbook @bankbook @bankbook This is in order=1.0-AOE28692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286922 @bankbook @bankbook @bankbook (OH) @bankbook/AIS2 @bankbook @bankbook @bankbook 'L=' and ' L'2 - @bankbook @bankbook @bankbook + 2Hemeris + 2Hor/aok2 @bankbook @bankbook @bankbook A is in a relationship of 1 and is in a structure of and . The advantage and the beneficial effect of the invention are as follows: The 1 invention proposes to control the porosity of porous silicon by adjusting the electrochemical corrosion parameters of silicon, such as, for example, by adjusting the electrochemical corrosion parameters of silicon. The structure of the neural electrode includes that a combination of porous silicon and silicon at the lowermost layer of. , The 2 degradation time in brain can be controlled by the porosity, and then the degradation time in the brain can be controlled by the porosity. The functional layer of porous silicon after degradation in brain tissue has a mechanical strength similar to that of brain tissue and therefore does not damage brain tissue so that the device is suitable for long-term brain neural signals. The 3 present invention proposes several processes for making porous silicons a in a process implementation of :Several methods for making porous silicon neural electrodes are listed below, and the method is based on the following: a. Also given is that a successfully manufactured nerve electrode device is in a. Description of the drawings Figure (a 1) is a diagram of the neural electrode structure of the present invention. Figure (a) of 2 the neural electrode structure of 1 the present invention is shown in and. A is 3 in, and 1 is in a relationship of, for example, and . A is 4 in, and is in a relationship of (40% a), and 40% /ajustrains a 40% is in a. Figure shows 5 that the anisotropic 2 etching of the porous silicon in the @banknum_@bank/amesas @banknum_num Buila is in a. A 6 is in, and is in a relationship of, for example, and . A is 7 in between a nerve probe head of the neural electrode and a cross section of the porous silicon in a. Specific implementation The following is detailed in connection with the accompanying drawings and embodiments in which: The present invention proposes a partially degradable porous silicon-based and polymer-based nerve electrode, and the structure thereof is as 1 - 2 shown in the following @. A neural electrode probe of the present invention may be partially inserted into a 1 portion of the brain tissue and is degraded in brain tissue environment and generates a substance that is harmless in the brain tissue environment.2 @bankbook @bankbook @bankbook (OH) @bankbook/AIS2 @bankbook @bankbook @bankbook 'L=' and ' L'2 @bankbook @bankbook @bankbook is in order to be. The probe portion outside the brain tissue is used as a substrate for supporting the electrode contact, and then connected to the external signal acquisition system after being bonded to the lead wire. Structural layers on the upper part of the porous silicon layer and the silicon layer are: are/are/are . The polymer may be in a ratio of one or more of, for example, and/or a mixture of one or more of and conductive carbon nanotubes. During the implantation of the neural electrode probe, the Wallantoin a is in a constant velocity perpendicular to the brain tissue and then inserted at a constant velocity into the brain tissue in a constant speed. In the weakly alkaline environment of the brain tissue, the porous silicon may undergo a chemical reaction in the environment to generate soluble biocompatible material, such as, and .2 @bankbook @bankbook @bankbook (OH) @bankbook/AIS2 @bankbook @bankbook @bankbook 'L=' and ' L'2 @bankbook @bankbook @bankbook A is in a relationship of 1, for example, and. : @ipitation and @ipitation Si+2OHR a-R-criminal /aok + 2Hemeris + 2Hor/aok2 @bankbook @bankbook @bankbook This is in order=1.0-AOE28692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286928692869286922 @bankbook @bankbook @bankbook (OH) @bankbook/AIS2 @bankbook @bankbook @bankbook 'L=' and ' L'2 - @bankbook @bankbook @bankbook + 2Hemeris + 2Hor/aok2 @bankbook @bankbook @bankbook A is in a relationship of 1 and is in a structure of and . The porosity of the porous silicon determines that the mechanical strength and dissolution rate of the material are in a. The porosity of the porous silicon for the neural electrode of the present invention is in between about a and 40% - 70% a unit_@ipitation. Implementation=@banknum_@bankbook @bankbook 1 The present embodiment is that a manufacturing method of a neural electrode device based on a porous silicon substrate is as follows: Is made to 1 be in a ratio of, for example, in the preparation of a porous silicon. A preparation method of the porous silicon preparation process is that the preparation method of the porous silicon can be in the anodic electrochemical corrosion method. An anodic electrochemical corrosion method is most commonly used and is compatible with a. The method takes platinum or graphite as an anode, and a silicon wafer patterned well as a cathode is made as a cathode in a HFCs solution of HFCs. Or platinum or graphite is deposited as an anode and a cathode, and a silicon wafer is settled in a mixture of HFCs/astringent and ethanol in a mixture of HFCs and ethanol. The corrosion rate is in a ratio of a size of a porous silicon pore size and a doping concentration of a monocrystalline silicon wafer and a concentration of a monocrystalline silicon wafer and a strength related to control of corrosion current. The porosity of 4 the porous silicon under several experimental conditions is listed in that: the resistivity of the porous silicon 60% under 70% several experimental conditions 0.003 -0 . 005 Ω cm is in 40% a. A is in 2, and the production of a degradable nerve electrode is in a ratio of, for example, and . The structures of the neural electrodes are respectively a functional layer of a degradable porous silicon support layer into which the auxiliary nerve electrode is inserted and a functional layer of a flexible polymer layer and a neural signal recording electrode. The production of the electrode of the present embodiment takes as 3 follows: a. For electrochemical corrosion production of a porous silicon structure, the present invention adopts a high ion-doped silicon slice. First through photolithography and deep-silicon etching, a trench for defining the 100 - 150 μm width of the electrode chip is in a relationship that is enough to define that of the 3 - 7 μm electrode chip 3. The trench is padded with a low-pressure chemical vapor deposition (a 2 - 4 μm), and a 0.1 - 0.3 μm surface smoothing process is followed by a 3. Through photolithography, a porous silicon region is defined and is etched into a through a dry ion etching technique and a. 3 , As in a step of 3; a is in a step of=(in the order of) and /astride jerk . The porosity of a porous silicon made by electrochemical methods in the partial area of the electrode probe is in the range of from 40% - 70%Then, the wall porous silicon is passivated by high temperature of the oxygen gas oven to achieve a physical chemical protection of porous silicon. Next, high-stress silicon nitride or silicon oxide is deposited to counteract the stress caused by the porous silicon-feeding device in a 3. A layer of flexible polymer is deposited on the electrode material layer and then deposited on the electrode material layer and then deposited on the electrode material layer and then deposited on the electrode 3 material layer. After photolithography and etching on the upper flexible polymer, the remaining metal is covered by a flexible polymer, and then the rest of the metal is covered by a flexible 3 polymer. The next photolithographic technique will define that: a 3 is in a relationship of, for example, and/3. Finally, the wafer back-side mechanical polishing process is performed to thin the silicon wafer to a desired device height, such as and 70 - 120 μm . Since the depth of the deep trench is greater than that of the device, and /astride jerk a is automatically regen 3=a. After having been as described above, the production of a neural electrode device based on porous silicon and a polymer is in a. Figure (a 6) and @ipitation of @ipitation of the neural electrode are in a. Figure (a)=7 a pattern of a porous silicon and a silicon portion and a pattern of porous silicon and a silicon portion is in a. It can be seen that the difference between them and the two boundary lines are in a. Example Overa is made of: 2 and @bankbook . This is in connection 1 with that of the isolation material such 3 as silicon nitride or polycrystalline 3 silicon, and then is then patterned to be in a. The next step of porous silicon formation will enter from the patterned window into the silicon substrate Wallantoin a. However, in this case, each isotropic Wallis a is made to be in the order of. The etched porous silicon is in, as 5 illustrated in, and. The following process method is in that 3 a channel etching of a 3 next step in the boundary of the device is in order to define that the etching of the porous silicon in the boundary of the device is=. Since the dry etching rate of the porous silicon is determined by the porosity of the porous silicon and the degree of oxidation, that is to be strictly controlled by the etching conditions of the porous silicon. Finally, the mechanical polishing of the back surface of the silicon wafer is in a ratio of, for example, in the required device thickness. Example Overa is made of: 3 and @bankbook . Firstly, a function layer of a flexible polymer and a metal is formed on a silicon 3 substrate and is in a relationship of: and . The device and other areas are then protected with silicon nitride or silicon oxide or some other passivation layer protective devices and other areas. The deep etching channel is of 3, and is in a relationship of (in) and . Finally, electrochemical corrosion of silicon is performed to generate a porous silicon Wallantoin a. As a result of the formation of porous silicon, the silicon under the functional layer of Wallantoin is eventually corroded to form a porous silicon layer. Finally, the mechanical polishing of the back surface of the silicon wafer is in a ratio of, for example, in the required device thickness. The invention belongs to the technical field of electrical sensors, and discloses a neural electrode based on porous silicon and polymers, a manufacturing process of the neural electrode, and an application of the neural electrode. The neural electrode comprises a substrate layer, and a structural layer on the substrate layer, wherein the structural layer adopts a sandwich structure in which flexible polymers, an electrode material layer and flexible polymers are arranged in sequence; the substrate layer comprises a porous silicon substrate and a silicon substrate; electrode contacts I and electrode contacts II are arranged on the upper surface of the structural layer; the electrode contacts I are used as brain signal recording contacts; and the electrode contacts II are connected with a brain external neural signal acquisition device after being bonded with external lead wires. The neural electrode is used for monitoring brain neural signals; after a porous silicon part is inserted into the brain tissues, the porous silicon can generate a soluble substance in an alkalescent environment of the brain tissues; and the neural electrode has the characteristics of small size, multiple channels, low power consumption, low cost, high performance stability, etc. Is made 1 to be in the order of: @bankbook, and. One of the structural layers, which is composed of a porous silicon substrate and a silicon substrate, is as follows: and . An electrically insulating layer is disposed between the substrate layer and the structural layer; the silicon substrate is of a high conductivity silicon material; and the porous silicon substrate is of a high conductivity silicon material 40 - 70%. The part of the neural electrode inserted into the brain tissue in part of the brain tissue is of a width smaller than that of the part of the brain tissue in which the part of the brain tissue is smaller than that outside the brain tissue. Is made 2 to be in the order of: @bankbook, and. A sandwich structure based 1 on porous silicon and a polymer as described in Claims comprises a layer of flexible polymer and a layer of flexible polymer, wherein the wall of the layer of flexible polymer is. Is made 3 to be in the order of: @bankbook, and. One or more of 1 the electrode material such as, and electrode contact number a, is in a ratio of, for example, and . Is made 4 to be in the order of: @bankbook, and. The process for manufacturing 1 a neural electrode based on porous silicon and a polymer as described in Claims a, is characterized in that the process specifically includes the following steps: and. The silicon 1 nitride and the thickness of the 0.1 - 0.3 μm a are sequentially deposited on the 2 - 4 μm surface of the silicon wafer and are in order of: and. One of 2 the areas in the electrode area is defined by photolithography, and then etched to the silicon surface by a dry ion etching technique, and then etched to a of the silicon surface by a dry ion etching technique. A is 3 in a porous silicon region by an electrochemical method; the porosity of the porous silicon is=1, 40% - 70% and. After depositing 4 silicon oxide or silicon nitride on the surface of the porous silicon and silicon substrate, silicon oxide or silicon nitride is deposited on the surface of the porous silicon and silicon substrate as an electrically insulating layer. The flexible 5 polymer surface in which the electrode material layer is deposited on the electrode material layer is, and then deposited on the electrode material layer, and then deposited on the electrode material layer. The remaining 6 metal is exposed on the upper flexible polymer by lithography and etching; the rest of the metal is covered by a flexible polymer; and then the remaining metal is covered by the flexible polymer. One of 7 the edge portions of the electrode device is regroetched by photolithographic techniques, and then the silicon wafer is thinned to a desired electrode device height by photolithographic technology. Is made 5 to be in the order of: @bankbook, and. A trench having a 4 depth greater than that 1 of the electrode chip is then deposited on the silicon 3 - 7 μm wafer and then 0.1 - 0.3 μm deposited on the silicon wafer in a 2 - 4 μm. Is made 6 to be in the order of: @bankbook, and. The preparation process of 4 porous silicon based on porous silicon and polymer in a mixture of HFCs and/is by controlling the porosity 3 of porous silicon to be in and . Is made 7 to be in the order of: @bankbook, and. Silicon nitride or silicon 4 oxide is formed as a passivation layer protection device and other areas in which silicon nitride or silicon oxide is deposited on a silicon substrate in order to form a porous silicon layer. Is made 8 to be in the order of: @bankbook, and. The application of the 1 porous silicon and polymer-based neural electrode according to any one of claims a through following is characterized in that the neural electrode is used for monitoring cerebral nerve signals and is in a.