CN117861985A - Nerve probe based on capacitive microcomputer ultrasonic transducer - Google Patents
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- CN117861985A CN117861985A CN202410011039.7A CN202410011039A CN117861985A CN 117861985 A CN117861985 A CN 117861985A CN 202410011039 A CN202410011039 A CN 202410011039A CN 117861985 A CN117861985 A CN 117861985A
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- 239000000523 sample Substances 0.000 title claims abstract description 77
- 210000005036 nerve Anatomy 0.000 title claims abstract description 43
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Abstract
The invention provides a nerve probe based on a capacitive microcomputer ultrasonic transducer, which relates to the technical field of nerve probes and comprises a probe main body and capacitive microcomputer ultrasonic transducer vibrating elements, wherein the capacitive microcomputer ultrasonic transducer vibrating elements are arranged on the probe main body in an array manner, and the probe main body is connected with an external computer; the structure of the capacitive microcomputer ultrasonic transducer vibrating element sequentially comprises an upper electrode, a vibrating diaphragm, a structural support column, an insulating layer, a lower electrode and a silicon substrate. The nerve probe is beneficial to realizing minimally invasive implantation of an ultrasonic transducer in a living body, and the cMUT can not only generate controllable ultrasonic stimulation in the living body, but also receive ultrasonic feedback so as to realize medical imaging in the living body.
Description
Technical Field
The invention relates to the technical field of nerve probes, in particular to a nerve probe based on a capacitive microcomputer ultrasonic transducer.
Background
In recent years, based on the maturation of surface micromachining technology and the deep research of ultrasonic transducers, capacitive micromachined ultrasonic transducers are becoming a research trend, because of their advantages of simple structure, low self noise, high electromechanical coupling coefficient, high resolution, high sensitivity, wide frequency band, good impedance matching with media, and the like, cmuts (capacitive micromachined ultrasonic transducers) are widely used by researchers in the fields of resource exploration, underwater topography detection, medical imaging, and the like.
In the field of medical imaging, in 2001, the university of Stenfu Khuri-Yakub research group developed a 1x64 array element one-dimensional cMUT linear array for ultrasonic imaging by using a flip-chip bonding technique, and then developed a 128x128 array element two-dimensional cMUT area array for three-dimensional ultrasonic imaging. In 2009, cMUT catheters composed of 1x24 arrays developed by Amin Nikoozadeh et al, university of stanford were used for intracardiac echocardiography. In 2014, the M.Wasequr Rashid et al of the university of George of Arrages of the Orchidactyl of America use a cMUT-on-CMOS integrated process technology to package a cMUT linear array into a chip on a front-end circuit, and designed a cardiovascular frequency division multiplexing measurement catheter for medical ultrasound. The use of cmuts in the medical field tends to mature.
The invention patent of China application number 201911357618.2 discloses an optoelectronic nerve probe integrated with an internal metal shielding layer and a preparation method thereof, wherein the optoelectronic nerve probe comprises an electrophysiological signal recording channel, a channel and a signal processing module, wherein the channel is used for conducting nerve electric signals from electrode points to an acquisition system; the laser diode power supply channel is used for conducting pulse current or voltage signals to a bonding pad of the nerve probe base part and used for driving a laser diode to work; and the metal shielding layer is integrated between the electrophysiological signal recording channel and the laser diode power supply channel. However, the prior art is large in size, difficult to implant, and still presents a risk when implanted into a living being.
Disclosure of Invention
In view of the above, the present invention provides a neural probe based on a capacitive micro-machined ultrasonic transducer, where the combination of the capacitive micro-machined ultrasonic transducer and the neural probe is beneficial to realizing minimally invasive implantation of the ultrasonic transducer in a living body, and the cMUT can not only generate controllable ultrasonic stimulation in the living body, but also receive ultrasonic feedback to realize medical imaging in the living body.
The technical scheme of the invention is realized as follows:
the invention provides a nerve probe based on a capacitive microcomputer ultrasonic transducer, which comprises a probe main body and capacitive microcomputer ultrasonic transducer vibrating elements, wherein the capacitive microcomputer ultrasonic transducer vibrating elements are arranged on the probe main body in an array manner, and the probe main body is connected with an external computer;
the structure of the capacitive microcomputer ultrasonic transducer vibrating element sequentially comprises an upper electrode, a vibrating diaphragm, a structural support column, an insulating layer, a lower electrode and a silicon substrate.
Further preferably, the capacitive micro-electromechanical ultrasonic transducer vibrating element is connected with the probe main body through a printed circuit, and the probe main body regulates and controls the capacitive micro-electromechanical ultrasonic transducer vibrating element through the external computer.
Further preferably, the nerve probe is formed by bonding the back surfaces of two identical single-sided probes by a thermal bonding technique, and the bonding site of the two single-sided probes forms a silicon plate bonding surface.
Further preferably, the capacitive microcomputer ultrasonic transducer vibrating elements are distributed on the front arrays of the two single-sided probes.
Further preferably, the nerve probe generates electrostatic force on the vibrating diaphragm by applying direct current bias voltage to the capacitive micro-electromechanical ultrasonic transducer vibrating element, so that the capacitive micro-electromechanical ultrasonic transducer vibrating element generates ultrasonic waves.
Further preferably, the frequency of the ultrasonic wave is changed by adjusting the internal structural parameters and external factors of the capacitive micro-electromechanical ultrasonic transducer vibrating element;
the structural parameters comprise a vibrating diaphragm radius, a vibrating diaphragm thickness, a vibrating diaphragm material, an electrode thickness and a cavity thickness; the external factors comprise the fluid medium environment in which the vibrating element is positioned and the external voltage.
Further preferably, the capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic transmitter and an ultrasonic receiver at the same time;
when the capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic transmitter, direct-current voltage is applied between the upper electrode and the lower electrode to generate strong electrostatic force, the vibrating diaphragm is pulled to the silicon substrate, and the vibrating diaphragm is vibrated to generate ultrasonic waves by applying alternating-current voltage with preset frequency between the upper electrode and the lower electrode;
when the capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic receiver, direct-current bias voltage is applied between the upper electrode and the lower electrode, the vibrating diaphragm resonates under the action of incident ultrasonic waves, the capacitance between the upper electrode and the lower electrode is changed, and the ultrasonic waves are received by detecting the change of the capacitance.
Further preferably, the preparation method of the capacitive microcomputer ultrasonic transducer vibrating element comprises the following steps:
(a) Depositing a layer of first metal film on a silicon substrate by a film deposition technology to serve as a lower electrode;
(b) Depositing an insulating layer on the lower electrode by using a thin film deposition technology;
(c) Forming a photoresist sacrificial layer on the insulating layer by using a photoresist sacrificial material, wherein the photoresist sacrificial layer is of an upper layer structure and a lower layer structure, the length of the lower layer structure is greater than that of the upper layer structure, and the height of the upper layer structure is greater than that of the lower layer structure;
(d) Filling an organic polymer on the photoresist sacrificial layer to form a structural layer, and cooling and hardening to obtain a structural support, wherein the structural layer completely covers the photoresist sacrificial layer;
(e) Removing the top structural support through wet etching to enable the structural support to generate an opening, forming two symmetrical structural support columns, and removing all photoresist sacrificial materials from the opening through ion etching;
(f) Obtaining a second metal film as an upper electrode by a distillation technology, and spin-coating a diaphragm material on the upper electrode to form a diaphragm;
(g) Bonding the vibrating diaphragm with two structural support columns through a thermal curing bonding technology, and forming a cavity among the vibrating diaphragm, the two structural support columns and the insulating layer;
(h) And patterning the upper electrode by utilizing an ion etching technology, and forming to obtain the capacitive microcomputer ultrasonic transducer vibrating element.
Further preferably, the organic polymer is PVC, the insulating layer is silica, and the diaphragm material is silicon nitride.
Further preferably, the first metal film is 2-5 micrometers, the second metal film is 2-5 micrometers, the insulating layer is 2-5 micrometers, and the diaphragm is 0.5-2.5 micrometers.
Compared with the prior art, the method has the following beneficial effects:
(1) The invention is beneficial to realizing minimally invasive implantation of the ultrasonic transducer in the organism, and the cMUT can not only generate controllable ultrasonic stimulation in the organism, but also receive ultrasonic feedback so as to realize medical imaging in the organism, and the device can greatly reduce implantation difficulty and physiological influence of the implanted device on the organism due to the small size;
(2) According to the invention, through the array arrangement of the vibrating elements of the capacitive microcomputer ultrasonic transducer, the nerve probe can realize multi-channel stimulation, namely, a plurality of vibrating elements on the probe main body can simultaneously generate ultrasonic stimulation, so that a wider nerve stimulation range is provided;
(3) According to the invention, two identical single-sided probes are combined through a thermocuring bonding technology, so that ultrasonic stimulation can be generated on the front side and the rear side of the nerve probe after implantation, the problem that stimulation dead angles exist when ultrasonic waves are released by single-sided vibrating elements is solved, the nerve probe can stimulate nerve tissues more comprehensively, and the stimulation effect is improved;
(4) The capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic transmitter and an ultrasonic receiver, the vibrating diaphragm is vibrated by the external voltage to generate ultrasonic stimulation, the ultrasonic stimulation can precisely act on nerve tissues to realize precise nerve stimulation, meanwhile, the frequency of ultrasonic waves can be adjusted by adjusting the external voltage to adapt to different application requirements, the vibrating diaphragm resonates under the action of incident ultrasonic waves to enable the capacitance between the upper electrode and the lower electrode to change, and ultrasonic signals can be converted into electric signals by detecting the change of the capacitance and transmitted back to an external computer for analysis. This may enable feedback reception or medical acoustic imaging, providing more comprehensive information.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic illustration of a neural probe structure according to an embodiment of the present invention;
FIG. 2 is a left side view of a nerve probe according to an embodiment of the present invention;
FIG. 3 is a flowchart of the operation of a nerve probe according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of an equivalent circuit of a cMUT vibrating element according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a preparation process of a cMUT vibrating element according to an embodiment of the present invention.
Detailed Description
The following description of the embodiments of the present invention will clearly and fully describe the technical aspects of the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, are intended to fall within the scope of the present invention.
As shown in fig. 1, the invention provides a nerve probe based on a capacitive micro-computer ultrasonic transducer, which comprises a probe main body 1 and capacitive micro-computer ultrasonic transducer vibrating elements 2, wherein the capacitive micro-computer ultrasonic transducer vibrating elements are arranged on the probe main body in an array manner, and the probe main body is connected with an external computer;
the structure of the capacitive microcomputer ultrasonic transducer vibrating element sequentially comprises an upper electrode, a vibrating diaphragm, a structural support column, an insulating layer, a lower electrode and a silicon substrate.
In a specific embodiment of the present invention, the capacitive micro-electromechanical ultrasonic transducer vibrating element is connected to the probe body through a printed circuit, and the probe body regulates and controls the capacitive micro-electromechanical ultrasonic transducer vibrating element through the external computer.
Referring to fig. 2, in an embodiment of the present invention, the nerve probe is formed by bonding two identical single-sided probes to each other by thermal bonding, and the bonding sites of the two single-sided probes form a bonding surface of the silicon plate. The capacitive microcomputer ultrasonic transducer vibrating elements are distributed on the front arrays of the two single-sided probes.
Specifically, the dashed line in fig. 2 is the position of the bonding surface of the silicon plate, the dashed line divides the nerve probe into a left part and a right part, namely two single-sided probes, the back surfaces of the two single-sided probes are bonded by a thermal curing bonding technology, and the capacitive microcomputer ultrasonic transducer vibrating elements are distributed on the front surfaces of the two single-sided probes in an array manner, so that ultrasonic stimulation can be generated on the front surface and the rear surface of the nerve probe after implantation, and the problem that the single-sided vibrating elements release ultrasonic stimulation dead angles is solved.
In a specific embodiment of the present invention, the neural probe generates an electrostatic force on the diaphragm by applying a dc bias voltage to the capacitive micro-electromechanical transducer element, so that the capacitive micro-electromechanical transducer element generates an ultrasonic wave.
The frequency of the ultrasonic wave is changed by adjusting the internal structural parameters and external factors of the vibrating element of the capacitive microcomputer ultrasonic transducer;
the structural parameters comprise a vibrating diaphragm radius, a vibrating diaphragm thickness, a vibrating diaphragm material, an electrode thickness and a cavity thickness; the external factors comprise the fluid medium environment in which the vibrating element is positioned and the external voltage.
The capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic transmitter and an ultrasonic receiver at the same time;
when the capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic transmitter, direct-current voltage is applied between the upper electrode and the lower electrode to generate strong electrostatic force, the vibrating diaphragm is pulled to the silicon substrate, and the vibrating diaphragm is vibrated to generate ultrasonic waves by applying alternating-current voltage with preset frequency between the upper electrode and the lower electrode;
when the capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic receiver, direct-current bias voltage is applied between the upper electrode and the lower electrode, the vibrating diaphragm resonates under the action of incident ultrasonic waves, the capacitance between the upper electrode and the lower electrode is changed, and the ultrasonic waves are received by detecting the change of the capacitance.
Specifically, the working flow of the nerve probe in this embodiment is shown in fig. 3, after the nerve probe is implanted into a living body, the nerve probe is powered by a direct-current voltage to activate, the nerve probe is driven by an external computer after being activated, the vibration of the vibrating diaphragm is caused by the applied voltage to generate ultrasonic stimulation, meanwhile, the vibrating element of the capacitive microcomputer ultrasonic transducer can also receive feedback ultrasonic waves, the vibration diaphragm is caused by the feedback ultrasonic waves to change capacitance, and an acoustic signal is converted into an electrical signal to be transmitted to the external computer for analysis, so that feedback receiving or medical acoustic imaging is realized. Specifically, in fig. 3, the flow of the solid arrows is that the capacitive micro-electromechanical ultrasonic transducer vibrating element is used as an ultrasonic transmitter, and the flow of the dotted arrows is that the capacitive micro-electromechanical ultrasonic transducer vibrating element is used as an ultrasonic receiver.
Specifically, when the nerve probe of the embodiment works, the equivalent circuit of the vibration element of the capacitive microcomputer ultrasonic transducer is shown in fig. 4, and as can be seen from fig. 4, when the vibration element works, the nerve probe passes through the vibrating diaphragm capacitor C 0 Negative capacitance-C 0 /n 2 Inductance L m And capacitor C m Realizes the electromechanical conversion of sound wave and the electromechanical conversion coefficient in the equivalent circuitIn particular, the method comprises the steps of,wherein S represents the diaphragm area, ε 0 Is the dielectric constant in vacuum, x is the displacement generated by vibration of the diaphragm, h e Is the effective gap height of the bipolar plates, which can be expressed as +.>d is the effective thickness of the diaphragm, ε r Is the relative dielectric constant of the vibrating diaphragm material, h 0 Is the initial gap height between the bipolar plates; negative capacitance-C 0 /n 2 The capacitance correction of the vibration film spring softening effect generated under the electromechanical action is shown, and when the direct current voltage is increased, the resonance frequency is reduced, so that the elastic coefficient of the vibration film is reduced; inductance L m And capacitor C m Then the mechanical impedance of the cMUT vibrating element is represented; when an external voltage is applied to the capacitor C m When in up, the capacitor C m Will vibrate so that the diaphragm will also vibrate, producing ultrasonic stimulation. At the same time, the vibration of the vibrating diaphragm also causes the capacitor C 0 And the change is carried out to generate a feedback signal, and the feedback signal is transmitted back to an external computer for analysis through feedback ultrasonic waves. The impedance Z represents the acoustic impedance of the surrounding medium, affecting the propagation and reflection of the acoustic wave. By adjusting parameters of each element in the equivalent circuit, sound wave output and feedback receiving with different frequencies and intensities can be realized.
Specifically, the operating principle of vibrating the diaphragm to generate ultrasonic stimulus is as follows:
under normal working condition of diaphragm, electrostatic force F generated by DC bias voltage e The membrane is deformed to generate displacement x of the membrane, and the mechanical property of the membrane is similar to a spring, and the membrane generates a linear restoring force F after the displacement k Under the interaction of the two forces, the vibrating diaphragm vibrates back and forth to generate ultrasonic waves; wherein the electrostatic force generated by the DC bias voltage can be expressed asWherein V represents the applied DC bias voltage, the elastic restoring force F k Satisfy Hooke's law F k ＝kx。
In this embodiment, vibration parameters of capacitive micro-electromechanical ultrasonic transducer vibration elements under different environments are simulated, and simulation results are shown in table 1 below:
table 1 vibration simulation data of capacitive micro-electromechanical ultrasonic transducer in different environments
| Medium (D) | Bias voltage/V | Resonant frequency/MHz | Maximum displacement/μm | Maximum intensity/dB |
| Vacuum | 61 | 0.66 | 0.373 | 17.495 |
| Water and its preparation method | 61 | 0.16 | 0.011 | 51.498 |
As can be seen from table 1, in water, the resonance frequency and the maximum displacement of the vibrating element are both low, the resonance frequency is the frequency at which the vibrating element generates maximum vibration in a specific environment, the maximum displacement indicates the maximum offset distance of the vibrating element in the vibration process, the resonance frequency is low, the stimulation to the biological tissue is small, the maximum displacement is lower, the stimulation to the biological tissue is also very small, and the safety and stability of the nerve probe can be ensured. Meanwhile, in water, the maximum intensity of the vibrating element is large, and the sound wave intensity can penetrate through organism tissues, so that the aim of stimulating nerves is fulfilled.
In a specific embodiment of the present invention, the preparation process of the capacitive micro-electromechanical ultrasonic transducer vibrating element is shown in fig. 5, and the preparation method includes:
(a) Depositing a layer of first metal film on a silicon substrate by a film deposition technology to serve as a lower electrode;
(b) Depositing an insulating layer on the lower electrode by using a thin film deposition technology;
(c) Forming a photoresist sacrificial layer on the insulating layer by using a photoresist sacrificial material, wherein the photoresist sacrificial layer is of an upper layer structure and a lower layer structure, the length of the lower layer structure is greater than that of the upper layer structure, and the height of the upper layer structure is greater than that of the lower layer structure;
(d) Filling an organic polymer on the photoresist sacrificial layer to form a structural layer, and cooling and hardening to obtain a structural support, wherein the structural layer completely covers the photoresist sacrificial layer;
(e) Removing the top structural support through wet etching to enable the structural support to generate an opening, forming two symmetrical structural support columns, and removing all photoresist sacrificial materials from the opening through ion etching;
(f) Obtaining a second metal film as an upper electrode by a distillation technology, and spin-coating a diaphragm material on the upper electrode to form a diaphragm;
(g) Bonding the vibrating diaphragm with two structural support columns through a thermal curing bonding technology, and forming a cavity among the vibrating diaphragm, the two structural support columns and the insulating layer;
(h) And patterning the upper electrode by utilizing an ion etching technology, and forming to obtain the capacitive microcomputer ultrasonic transducer vibrating element.
Specifically, the organic polymer is PVC, the insulating layer is silicon dioxide, and the vibrating diaphragm material is silicon nitride. The first metal film is 2-5 microns, the second metal film is 2-5 microns, the insulating layer is 2-5 microns, and the vibrating diaphragm is 0.5-2.5 microns.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.
Claims (10)
1. The nerve probe based on the capacitive microcomputer ultrasonic transducer is characterized by comprising a probe main body and capacitive microcomputer ultrasonic transducer vibrating elements, wherein the capacitive microcomputer ultrasonic transducer vibrating elements are arranged on the probe main body in an array manner, and the probe main body is connected with an external computer;
the structure of the capacitive microcomputer ultrasonic transducer vibrating element sequentially comprises an upper electrode, a vibrating diaphragm, a structural support column, an insulating layer, a lower electrode and a silicon substrate.
2. The capacitive micro-machined ultrasonic transducer-based nerve probe of claim 1, wherein the capacitive micro-machined ultrasonic transducer element is connected to the probe body via a printed circuit, and the probe body regulates the capacitive micro-machined ultrasonic transducer element via the external computer.
3. The capacitive micro-machined ultrasonic transducer-based nerve probe of claim 1, wherein said nerve probe is formed by bonding the back surfaces of two identical single-sided probes by a thermocompression bonding technique, and the junction of two single-sided probes forms a silicon plate bonding surface.
4. A capacitive micro-machined ultrasound transducer-based nerve probe as claimed in claim 3 wherein the frontal array of two single-sided probes is distributed with the capacitive micro-machined ultrasound transducer vibrating elements.
5. The capacitive micro-machined ultrasonic transducer-based nerve probe of claim 2, wherein said nerve probe generates electrostatic force on the diaphragm by applying a dc bias voltage to said capacitive micro-machined ultrasonic transducer element, causing said capacitive micro-machined ultrasonic transducer element to generate ultrasonic waves.
6. The capacitive micro-machined ultrasonic transducer-based nerve probe of claim 5, wherein the frequency of the ultrasonic wave is varied by adjusting the structural parameters and external factors inside the capacitive micro-machined ultrasonic transducer vibrating element;
the structural parameters comprise a vibrating diaphragm radius, a vibrating diaphragm thickness, a vibrating diaphragm material, an electrode thickness and a cavity thickness; the external factors comprise the fluid medium environment in which the vibrating element is positioned and the external voltage.
7. The capacitive micro-machined ultrasonic transducer-based nerve probe of claim 5, wherein said capacitive micro-machined ultrasonic transducer vibrating element acts as both an ultrasonic transmitter and an ultrasonic receiver;
when the capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic transmitter, direct-current voltage is applied between the upper electrode and the lower electrode to generate strong electrostatic force, the vibrating diaphragm is pulled to the silicon substrate, and the vibrating diaphragm is vibrated to generate ultrasonic waves by applying alternating-current voltage with preset frequency between the upper electrode and the lower electrode;
when the capacitive microcomputer ultrasonic transducer vibrating element is used as an ultrasonic receiver, direct-current bias voltage is applied between the upper electrode and the lower electrode, the vibrating diaphragm resonates under the action of incident ultrasonic waves, the capacitance between the upper electrode and the lower electrode is changed, and the ultrasonic waves are received by detecting the change of the capacitance.
8. The nerve probe based on the capacitive micro-computer ultrasonic transducer according to claim 1, wherein the preparation method of the capacitive micro-computer ultrasonic transducer vibrating element comprises the following steps:
(a) Depositing a layer of first metal film on a silicon substrate by a film deposition technology to serve as a lower electrode;
(b) Depositing an insulating layer on the lower electrode by using a thin film deposition technology;
(c) Forming a photoresist sacrificial layer on the insulating layer by using a photoresist sacrificial material, wherein the photoresist sacrificial layer is of an upper layer structure and a lower layer structure, the length of the lower layer structure is greater than that of the upper layer structure, and the height of the upper layer structure is greater than that of the lower layer structure;
(d) Filling an organic polymer on the photoresist sacrificial layer to form a structural layer, and cooling and hardening to obtain a structural support, wherein the structural layer completely covers the photoresist sacrificial layer;
(e) Removing the top structural support through wet etching to enable the structural support to generate an opening, forming two symmetrical structural support columns, and removing all photoresist sacrificial materials from the opening through ion etching;
(f) Obtaining a second metal film as an upper electrode by a distillation technology, and spin-coating a diaphragm material on the upper electrode to form a diaphragm;
(g) Bonding the vibrating diaphragm with two structural support columns through a thermal curing bonding technology, and forming a cavity among the vibrating diaphragm, the two structural support columns and the insulating layer;
(h) And patterning the upper electrode by utilizing an ion etching technology, and forming to obtain the capacitive microcomputer ultrasonic transducer vibrating element.
9. The capacitive micro-machined ultrasonic transducer-based nerve probe of claim 8, wherein said organic polymer is PVC, said insulating layer is silicon dioxide, and said diaphragm material is silicon nitride.
10. The capacitive micro-machined ultrasonic transducer-based nerve probe of claim 8, wherein said first metal film is 2-5 microns, said second metal film is 2-5 microns, said insulating layer is 2-5 microns, and said diaphragm is 0.5-2.5 microns.
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| CN202410011039.7A CN117861985A (en) | 2024-01-04 | 2024-01-04 | Nerve probe based on capacitive microcomputer ultrasonic transducer |
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