CN217588943U - Carbon-based field effect transistor pressure sensor for Chinese medicine pulse condition recurrence - Google Patents

Abstract

The utility model provides a carbon-based field effect transistor pressure sensor for Chinese medicine pulse manifestation recurrence, which comprises three independent pulse manifestation recurrence channels, wherein each pulse manifestation recurrence channel consists of a pulse sensing component and a CNT-FET type sensing component which is correspondingly arranged; the CNT-FET type sensing component of each pulse manifestation recurrence channel is electrically connected with a pulse induction component directly acting on the skin surface of a human body through a conductive medium, the pulse induction component is provided with a finger simulation channel for inducing pulse manifestation and changes thereof, the induction output of the finger simulation channel is transmitted to the corresponding CNT-FET type sensing component through the conductive medium, and pulse manifestation data are obtained based on the response output of the CNT-FET type sensing components of the three pulse manifestation recurrence channels. The utility model provides a carbon base field effect transistor pressure sensor for traditional chinese medical science pulse manifestation recurrence reaches the micron order level, can realize the real-time supervision to pulse signal high sensitivity, low-power consumption, portable, safety, and the pulse manifestation recurs visually, promotes traditional chinese medical science to inherit.

Description

Carbon-based field effect transistor pressure sensor for Chinese medicine pulse condition recurrence

Technical Field

The utility model belongs to the technical field of carbon back field effect transistor technique and specifically relates to an application in traditional chinese medical science pulse manifestation recurrence field, particularly relate to a carbon back field effect transistor pressure sensor for traditional chinese medical science pulse manifestation recurrence.

Background

Taking pulses also known as pulse-feeling is a diagnostic method of pressing the arteries of a patient (cun guan chi) by hand to understand the intrinsic changes of the disease according to the pulse condition. There are approximately 28 kinds of pulse conditions, each of which is a reflection of the human body's function and has a corresponding range of symptoms.

Monitoring of the pulse is important in medical research and clinical diagnosis. Significant changes in pulse condition may occur due to insignificant changes in the external environment. If the pulse is within the physiological regulation range, the pulse is normal; beyond the physiological range, the pulse condition is pathological. With the interference, the pulse condition is sometimes inaccurate and reliable. At this time, the experience is especially important, doctors with high pulse feeling skills and rich experience can accurately find pathological changes, and general doctors may have unclear diagnosis or even wrong diagnosis.

Meanwhile, the pulse conditions obtained by experienced traditional Chinese medicine doctors in the pulse feeling process and the diagnosis performed according to the pulse conditions are judged based on the experience accumulation and the pulse conditions, the pulse conditions are numerous, different pulse conditions and changes thereof are difficult to accurately express by intuitive characters and languages sometimes, so that direct and intuitive and objective pulse and pulse condition data are difficult to obtain for learning and practice in the post training and practice process of the traditional Chinese medicine doctors in practice/practice, and teaching and practice simulation cannot be performed in a visual mode.

At present, the traditional Chinese medicine hospital is very bulky in instruments for monitoring the pulse condition, and the pulse condition is difficult to be continuously monitored.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a carbon base field effect transistor pressure sensor and preparation for traditional chinese medical science pulse manifestation recurrence aims at realizing the recurrence of traditional chinese medical science pulse manifestation, obtains visual result, and existing being favorable to reference or daily health diagnosis as clinical diagnosis, based on visual expression, more do benefit to traditional chinese medical science diagnosis and teaching simultaneously, promote traditional chinese medical science to pass.

According to the utility model discloses the first aspect of purpose provides a receive carbon base field effect transistor pressure sensor who is used for traditional chinese medical science pulse manifestation recurrence of nanometer processing, reaches the micron order level, can realize pulse signal high sensitivity, low-power consumption, portable, safe real-time supervision, simultaneously, can recurrence pulse manifestation, obtains visual result, promotes traditional chinese medical science to bear.

The carbon-based field effect transistor pressure sensor for Chinese medicine pulse manifestation recurrence comprises three independent pulse manifestation recurrence channels, wherein each pulse manifestation recurrence channel consists of a pulse sensing component and a CNT-FET type sensing component which is correspondingly arranged;

the CNT-FET type sensing component of each pulse condition recurrence channel is electrically connected with a pulse sensing component directly acting on the skin surface of a human body through a conductive medium, the pulse sensing component is provided with a finger simulation channel for sensing pulse conditions and changes thereof, the sensing output of the finger simulation channel is transmitted to the corresponding CNT-FET type sensing component through the conductive medium, and pulse condition data is obtained based on the response output of the CNT-FET type sensing components of the three pulse condition recurrence channels.

As an optional example, the pulse sensing component is composed of a piezoelectric material, a lower electrode, an upper electrode, a finger simulation channel and an air tube;

the CNT-FET type sensing component is composed of a silicon-based substrate, a CNT channel layer, a dielectric layer, a source electrode, a drain electrode and a top gate electrode.

As an alternative example, the silicon-based substrate defines a first surface and an opposite second surface, with the first surface being a subsequently prepared growth surface;

the CNT channel layer is positioned on the first surface of the silicon-based substrate and is positioned between the source electrode and the drain electrode;

forming a CNT channel layer in the channel region by etching the CNT thin film between the source electrode and the drain electrode;

the dielectric layer is positioned on the upper surface of the CNT channel layer;

the source electrode and the drain electrode are positioned at two sides of the dielectric layer and the CNT channel layer, and are oppositely arranged and spaced;

the top gate electrode is positioned on one side of the dielectric layer far away from the silicon-based substrate, and the top gate electrode is not in contact with the source electrode, the drain electrode and the CNT channel layer.

As an alternative example, in each pulse manifestation reproduction channel, the piezoelectric material defines an upper surface and a lower surface;

the lower electrode and the upper electrode are respectively positioned on the lower surface and the upper surface of the piezoelectric material; the lower electrode and the upper electrode are both in a thin-layer structure;

the lower electrode and the source electrode can be electrically connected through a first medium;

the upper electrode and the top gate electrode can be electrically connected through a second medium;

the finger simulation channel is positioned on the surface of the upper electrode;

the air pipe is communicated with the finger simulation channel and is used for introducing air into the finger simulation channel or exhausting air from the finger simulation channel;

in each pulse condition recurrence channel, the flow and volume of gas introduced into the finger simulation channel through the trachea are controlled to realize the internal pressure control of the finger simulation channel, and the gas is downwards applied to the piezoelectric material and the lower electrode so as to act on the pulse taking position on the surface of a human body.

As an alternative example, each finger simulation channel is independent and isolated from each other, such that each finger simulation channel is independently pneumatically controlled.

As an alternative example, the piezoelectric material, the lower electrode and the upper electrode are all wrapped by PET, wherein the thickness of the PET is 25-50um. After the upper electrode, the piezoelectric material and the lower electrode are integrally packaged by PET, the PET is directly contacted with the surface of a human body.

As an optional example, the finger simulation channel includes a first PDMS layer with a thin structure and a second PDMS layer with a concave microstructure, the first PDMS layer with the thin structure is located on the upper surface of the upper electrode, the second PDMS layer with the concave microstructure is located on the upper surface of the first PDMS layer, the first PDMS layer and the second PDMS layer are bonded together to form the finger simulation channel, and a cavity is formed inside the finger simulation channel;

the pressure of the cavity inside the finger simulation channel is changed by introducing gas into the cavity, so that pulse taking of traditional Chinese medicine is simulated.

By above the technical scheme of the utility model, its beneficial effect who is showing lies in:

the utility model provides a carbon base field effect transistor pressure sensor for traditional chinese medical science pulse manifestation reappears has solved traditional chinese medical science and has been caused the diagnosis incorrect and can't utilize the problem that visual pulse manifestation was presented to change and is taught and practiced because of experience is insufficient, subjectivity strong, through the utility model discloses a preparation technology of processing a little, can be compatible with CMOS semiconductor preparation technology, abandon and adopt traditional huge equipment to monitor the pulse, through the utility model discloses a design can realize the preparation and the integration of micron level device, realizes the miniaturization and the real-time portable detection of device, combines the advantage of the high sensitivity of CNT-FET sensor, low-power consumption, can realize the real-time supervision reappears to the pulse manifestation, reaches visual pulse manifestation reappears;

the utility model provides a carbon base field effect transistor pressure sensor for traditional chinese medical science pulse manifestation recurrence turns into voltage signal with pulse signal through piezoelectric material, because the electrode at piezoelectric material both ends passes through the wire and is connected to field effect transistor's grid and source electrode, consequently the change of piezoelectric material voltage shows the change of voltage on the grid to arouse the change of field effect transistor channel current. Therefore, the pulse condition can be converted into a visual result, the pulse taking efficiency and the diagnosis accuracy of the traditional Chinese medicine are improved, and the inheritance of the traditional Chinese medicine is promoted.

Simultaneously, high performance's field effect transistor combines the back with piezoelectric material, can high sensitivity, low-power consumption carry out real-time supervision, with prior art adoption traditional huge equipment go to monitor the pulse, the utility model discloses can integrate, miniaturize, more portable and light and handy, can realize high sensitivity, low-power consumption, portable, the safe real-time supervision to pulse signal, realize real-time, high sensitive pulse condition reappearance.

It should be understood that all combinations of the foregoing concepts and additional concepts described in greater detail below can be considered as part of the inventive subject matter of the present disclosure unless such concepts are mutually inconsistent. In addition, all combinations of claimed subject matter are considered a part of the inventive subject matter of this disclosure.

The foregoing and other aspects, embodiments and features of the present teachings can be more fully understood from the following description taken in conjunction with the accompanying drawings. Additional aspects of the present invention, such as features and/or advantages of exemplary embodiments, will be apparent from the description which follows, or may be learned by practice of the specific embodiments in accordance with the teachings of the present invention.

Drawings

The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

fig. 1 is a schematic diagram of a carbon-based field effect transistor pressure sensor for pulse manifestation reproduction in traditional chinese medicine according to an exemplary embodiment of the present invention.

Fig. 2 is a schematic diagram of an independent pulse-recurrence channel of a carbon-based field effect transistor pressure sensor for pulse-recurrence in traditional chinese medicine according to an exemplary embodiment of the present invention.

Fig. 3 is a schematic diagram of a pulse sensing assembly of a carbon-based field effect transistor pressure sensor for Chinese medical pulse manifestation recurrence according to an exemplary embodiment of the present invention.

Fig. 4 is a schematic diagram of a process for manufacturing a CNT-FET type sensing element of a carbon-based field effect transistor pressure sensor for pulse manifestation reproduction in traditional chinese medical science according to an exemplary embodiment of the present invention.

Fig. 5 is a graph showing the dynamic force test results of the carbon-based fet pressure sensor for pulse manifestation reproduction in the embodiment of fig. 1 according to the present invention.

Fig. 6 is a diagram illustrating the sensitivity test result of the carbon-based field effect transistor pressure sensor for pulse manifestation reproduction in traditional chinese medical science according to the embodiment of the present invention in fig. 1.

Fig. 7 is a schematic diagram of the current response to pressure of a carbon-based field effect transistor pressure sensor for pulse manifestation reproduction in traditional chinese medical science according to the embodiment of the present invention in fig. 1.

Fig. 8a is a schematic voltage response to pressure of a carbon-based field effect transistor pressure sensor for pulse manifestation reproduction in traditional chinese medical science according to the embodiment of the present invention in fig. 1.

Fig. 8b is a schematic diagram of a transfer curve of a carbon-based field effect transistor pressure sensor for pulse manifestation reproduction in traditional chinese medical science according to the embodiment of the present invention shown in fig. 1.

Fig. 9 is a schematic diagram of the pulse test result of the carbon-based fet pressure sensor for pulse manifestation reproduction in the embodiment of fig. 1 according to the present invention.

Detailed Description

For a better understanding of the technical aspects of the present invention, specific embodiments are described below in conjunction with the appended drawings.

In this disclosure, aspects of the present invention are described with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. Embodiments of the present disclosure are not necessarily intended to encompass all aspects of the invention. It should be appreciated that the various concepts and embodiments described above, as well as those described in greater detail below, may be implemented in any of numerous ways, as the disclosed concepts and embodiments are not limited to any implementation. Additionally, some aspects of the present disclosure may be used alone or in any suitable combination with other aspects of the present disclosure.

Carbon-based field effect transistor pressure sensor for Chinese medicine pulse condition recurrence

In connection with the exemplary embodiment shown in fig. 1 and 2, the carbon-based field effect transistor pressure sensor for pulse manifestation in traditional chinese medicine comprises three independent pulse manifestation channels 100, each pulse manifestation channel 100 being formed by a pulse sensing element 110 and a CNT-FET type sensing element 120 disposed correspondingly thereto.

Each pulse condition recurrence channel includes a silicon substrate 10, a CNT channel layer 20, a dielectric layer 30, a source electrode 40, a drain electrode 41, a top gate electrode 42, a piezoelectric material 60, a lower electrode 50, an upper electrode 51, a finger simulation channel 72, and a gas pipe 80.

As shown in fig. 1 and 2, the piezoelectric material 60, the lower electrode 50, the upper electrode 51, the finger simulation channel 72 and the air tube 80 constitute a pulse sensing component 110.

As shown in fig. 1 and 2, the silicon-based substrate 10, the CNT channel layer 20, the dielectric layer 30, the source electrode 40, the drain electrode 41, and the top gate electrode 42 constitute a CNT-FET type sensing element 120.

Referring to fig. 1 and 2, the sensing component of each pulse-manifestation recurrence channel is electrically connected to the pulse-sensation component directly acting on the skin surface of the human body through a conductive medium, each pulse-sensation component has a finger-simulation channel for sensing the pulse manifestation and the change thereof, the sensing output of the finger-simulation channel is transmitted to a corresponding sensing component through the conductive medium, and pulse-manifestation data is obtained through the response output of the sensing components of the three pulse-manifestation recurrence channels.

Sensing assembly

Referring to fig. 1, a silicon-based substrate 10 defines a first surface and an opposing second surface, the first surface being used as a growth surface for subsequent fabrication as shown in connection with fig. 1 for ease of illustration. The silicon-based substrate 10 may be a P-type silicon substrate.

Referring to fig. 1, the cnt channel layer 20 is located at a first surface of the silicon-based substrate 10 at a position between the source electrode 40 and the drain electrode 41. The CNT channel layer 20 is formed of a mesh-shaped carbon nanotube having a thickness controlled to be 0.5 to 2nm.

In an alternative example, a CNT film is deposited to a certain thickness on the first surface of the silicon-based substrate 10, and then the source electrode 40 and the drain electrode 41 are fabricated on the CNT film.

The CNT thin film between the source electrode 40 and the drain electrode 41 is etched to form the CNT channel layer 20 in the channel region.

As illustrated in fig. 1, a dielectric layer 30 is located on the upper surface of the CNT channel layer 20. As an alternative example, the dielectric layer 30 is a metal oxide dielectric layer such as yttria, or a dielectric layer made of other materials, and the thickness of the dielectric layer is 6-10nm.

As in the example of fig. 1, the source electrode 40 and the drain electrode 41 are located at positions on both sides of the CNT channel layer 20 and the dielectric layer 30, and the source electrode 40 and the drain electrode 41 are disposed opposite to each other and spaced apart from each other.

As in the example of fig. 1, the top gate electrode 42 is located on a side of the dielectric layer away from the silicon-based substrate 10, and the top gate electrode 42 is not in contact with the source electrode 40, the drain electrode 41, and the CNT channel layer 20.

As shown in fig. 1, the dielectric layer 30 on the upper surface of the CNT channel layer 20 covers a portion of the surface of the CNT channel layer 20 and may be shaped and sized to fit over the top gate electrode 42.

In some embodiments, the top gate electrode 42 and the dielectric layer 30 may also be configured to be larger or smaller in size, and the top gate electrode 42 is located between the source electrode 40 and the drain electrode 41 and is not in contact with either the source electrode 40 or the drain electrode 41.

In an alternative embodiment, the source electrode 40 and the drain electrode 41 are both strip-shaped electrodes with a certain thickness, such as strip-shaped gold electrodes. The source electrode and the drain electrode have the same thickness, the thickness is 60-80nm, the length is more than 30 μm, and the width is more than 5 μm.

In an alternative embodiment, the top gate electrode 42 is a stripe-shaped gold electrode, spaced apart from the source electrode 40 and the drain electrode 41, and vertically disposed on the dielectric layer 30. In some examples, the top gate electrode 42 is 30-50nm thick and over 1200um long.

Pulse induction assembly

Referring to fig. 1, 2 and 3, the piezoelectric material 60, the lower electrode 50, the upper electrode 51, the finger simulation channel 72 and the air tube 80 disposed corresponding to the finger simulation channel 72 constitute a pulse sensing component.

The finger simulation channel 72 forms an independent pulse induction channel and is used for simulating pulse taking of traditional Chinese medicine under a given pressure condition.

The piezoelectric material 60 defines an upper surface and a lower surface. The thickness of the piezoelectric material is 40-60nm.

In alternative embodiments, the piezoelectric material 60 may be formed in a thin film shape using a piezoelectric material such as PVDF or PZT.

The lower electrode 50 and the upper electrode 51 are respectively located on the lower surface and the upper surface of the piezoelectric material 60. The lower electrode 50 and the upper electrode 51 are both provided as thin layers.

In some embodiments, the lower electrode 50 and the upper electrode 51 are the same thickness, ranging from 5-20nm.

In an alternative embodiment, the piezoelectric material 60, the lower electrode 50, and the upper electrode 51 are all encapsulated by PET, wherein the PET is 25-50um thick.

After the upper electrode, the piezoelectric material and the lower electrode are integrally packaged by PET, the PET is directly contacted with the surface of a human body.

The lower electrode 50 and the source electrode 40 may be electrically connected through a first medium 90, such as a conductive wire or a conductive metal lead.

The upper electrode 51 and the top gate electrode 42 may be electrically connected through a second dielectric 91, such as a conductive wire or a conductive metal lead.

In each pulse manifestation generation channel, an air tube 80 leads into the finger simulation channel 72 for introducing air into the finger simulation channel 72 or exhausting air from the finger simulation channel 72.

In an alternative embodiment, each air tube 80 may be controlled by a configured air pump and control of the air pump to achieve flow and volume control of air to achieve internal pressure control of each finger simulation channel 72, applied down to the piezoelectric material 60, the lower electrode 50, and thereby acting on pulse taking locations on the surface of the human body. And the feedback of the human pulse under the corresponding pressure is taken as a sensing signal and is output to the sensing component through the pulse sensing component, so that the simulation and the reappearance of the pulse condition are realized.

Each finger simulation channel 72 is independent and isolated from each other so that each finger simulation channel 72 can be independently pneumatically controlled.

As an alternative embodiment, the finger simulation channel 72 is molded from an insulating material, such as PDMS.

As an alternative embodiment, each finger simulation channel 72 includes a first PDMS layer 70 of a thin layer structure and a second PDMS layer 71 of a concave microstructure, the first PDMS layer 70 of the thin layer structure is located on the upper surface of the upper electrode 51, the second PDMS layer 71 of the concave microstructure is located on the upper surface of the first PDMS layer 70, and the two layers are bonded together to form the finger simulation channel 72, and a cavity is formed inside the finger simulation channel. The pressure of the finger simulation channel 72 is changed by introducing gas into the cavity inside the finger simulation channel, so that pulse taking of traditional Chinese medicine is simulated.

In an alternative embodiment, the thickness of the first layer of PDMS is 10-50um; the thickness of the second layer PDMS is 4000-6000um.

Referring to fig. 2 and 3, the concave microstructures of the second layer of PDMS are strip-shaped concave structures, and the external dimensions have a length of 1-1.2cm and a width of 0.5-1cm.

Under the pressure control condition that different pulse conditions correspond, through the pulse sensing subassembly human pulse condition of response, the pressure signal of pulse condition feedback passes through pulse sensing subassembly output to sensing subassembly, because every finger simulation passageway 72 of pulse sensing subassembly all controls independently and independently, can realize the recurrence to the pulse condition from this.

In an alternative embodiment, the application of pressure to three pulse manifestation recurrence channels can be controlled by combining twenty-eight pulse manifestations of traditional Chinese medicine.

As an optional embodiment, the three pulse condition recurrence channels can be designed in an integrated mode, and the three pulse sensing components are integrated, so that the three pulse sensing components are beneficial to being integrally contacted and attached to the surface of a human body. Correspondingly, the CNT-FET type sensing component is integrated in an advantageous manner.

Preparation method

In the embodiment of the present invention, three independent pulse reproduction channels are configured in the same manner, and as an alternative, the CNT-FET type sensing element may be fabricated by a micro-nano processing technique.

As an alternative example, the process of preparing the CNT-FET type sensing element and the correspondingly disposed pulse sensing element in each pulse manifestation multiplexing channel includes the following steps:

step 1, preparing a silicon-based substrate 10 and depositing a CNT film on the upper surface of the silicon-based substrate, wherein the thickness is controlled to be 0.5-2nm; alternatively, the silicon-based substrate 10 employs Si/SiO ₂ A substrate;

step 2, exposing the source electrode (S), the drain electrode (D) and the metal lead by using a photoetching machine, depositing metal with a certain thickness by using an electron beam process, and forming the source electrode (S), the drain electrode (D) and the metal lead;

step 3, the Si/SiO deposited with the CNT film is subjected to spin coater ₂ The structural surface is subjected to glue homogenizing, a corresponding pattern is exposed by utilizing a photoetching process, and the CNT film is etched to obtain a CNT channel layer;

step 4, exposing the dielectric layer by using a photoetching machine, and depositing certain metal by using an electron beam process to form the dielectric layer;

step 5, glue homogenizing and exposure are carried out again, the top gate electrode (top-G) and the metal lead are exposed, metal with a certain thickness is deposited by using an electron beam process, and the top gate electrode (top-G) and the metal lead are formed;

step 6, depositing metal with a certain thickness on the upper surface and the lower surface of the piezoelectric material by using an electron beam coating instrument to form an upper electrode and a lower electrode of the piezoelectric material;

step 7, packaging the piezoelectric material and the corresponding upper electrode and lower electrode by using PET;

step 8, pouring PDMS on the male mold, and demolding after curing to form PDMS with a concave microstructure;

step 9, pouring PDMS on the Si substrate, curing and demolding to form PDMS with a smooth thin-layer structure;

step 10, bonding two layers of PDMS to form a finger simulation channel;

and 11, respectively connecting the source electrode with the lower electrode of the piezoelectric material and connecting the top gate electrode with the upper electrode of the piezoelectric material by using a lead.

As a specific example, the specific preparation process of a pulse-condition-recurring channel of a carbon-based field effect transistor pressure sensor for Chinese medicine pulse-condition recurrence comprises the following steps:

firstly, depositing a CNT film with a certain thickness on the upper surface of a silicon-based substrate; exposing a source electrode, a drain electrode and a metal lead of the device by using an ultraviolet photoetching machine, and depositing metal with the thickness of 80nm by using an electron beam process to form the source electrode, the drain electrode and the metal lead;

Si/SiO with CNT film deposited on spin coater using LOR and S1813 photoresist ₂ The surface of the two-layer structure is subjected to glue homogenizing, and then the CNT film is etched through photoetching and oxygen plasma etching (RIE) to form a CNT channel layer;

exposing the dielectric layer by using an ultraviolet lithography machine, and depositing metal with the thickness of 6nm by using an electron beam process to form a gate dielectric layer;

then, exposing the top gate electrode and the metal lead of the device by using an ultraviolet photoetching machine, and depositing metal with the thickness of 40nm by using an electron beam process to form the top gate electrode and the metal lead;

depositing metal with the thickness of 100nm on the upper surface and the lower surface of the piezoelectric material by using an electron beam coating instrument to form an upper electrode and a lower electrode of the piezoelectric material;

encapsulating the piezoelectric material with PET, optionally including encapsulation of the piezoelectric material, the upper electrode, and the lower electrode;

pouring PDMS on the male mold, and demolding after curing to form PDMS with a concave microstructure; wherein, SU8 can be used for preparing a male die in advance for use;

then pouring PDMS on the silicon substrate, demoulding after curing to form PDMS with a flat thin-layer structure, and bonding the PDMS on the surface of the upper electrode wrapping PET in a proper way;

bonding the two layers of PDMS, for example, by combining the two layers of PDMS using an oxygen plasma, to form a finger analog channel;

and finally, respectively connecting the lead with a source electrode of the field effect transistor and a lower electrode of the piezoelectric material by using silver colloid, and connecting the top gate electrode with an upper electrode of the piezoelectric material.

In the embodiment of the present invention, the design size of the carbon-based field effect transistor pressure sensor for Chinese medicine pulse manifestation recurrence prepared by the method of the example shown in fig. 3 and 4 is as follows:

a source electrode: the length is 150um, the width is 18um, and the thickness is 80nm;

a drain electrode: the length is 150um, the width is 18um, and the thickness is 80nm;

top gate electrode: the length is 1200um, the width is 10um, and the thickness is 40nm;

the size of the output electrode (pad) is more than 300 μm and 300 μm, and the thickness is 800nm;

piezoelectric material: 2.5cm long, 1.5cm wide and 50um thick;

upper and lower electrodes: 2.3cm long, 1.4cm wide and 10nm thick;

first layer PDMS: the length is 203cm, the width is 1.4cm, and the thickness is 40um;

the second layer of PDMS is 2cm long, 1cm wide and 5000um thick.

Pulse detection

With reference to fig. 1, 2 and 3, the gas is introduced into the finger simulation channel 72 through three gas tubes, and the generated gas pressures are different when the gas is introduced into three fingers of a pulse taking doctor in different volumes.

When in detection, the fingers of the human body exert different forces, and the monitored pulse condition is different.

Under a certain specific pressure, the pulse beat is converted into a voltage signal by the piezoelectric material, the piezoelectric material is connected with a field effect transistor (namely a CNT-FET type sensing component) through a lead, and an equivalent circuit is that the capacitance of the piezoelectric material is connected with the gate capacitance of the field effect transistor in series, so that the change of the voltage of the piezoelectric material is expressed as the change of the voltage on the gate, thereby causing the change of the channel current of the field effect transistor. When negative potential is generated at two ends of the piezoelectric material, namely negative voltage is applied at two ends of the grid source, hole accumulation is formed in the carbon nano tube serving as the conductive channel, and channel current is increased. When positive potential is generated at two ends of the piezoelectric material, namely positive voltage is applied to two ends of the grid source, hole carriers in the carbon nano tube serving as a conductive channel are exhausted, and channel current is reduced.

Based on the principle, when the pressure sensor provided by the embodiment of the invention is used for testing pulse conditions, a certain voltage V is applied between the source electrode and the drain electrode of the sensor _DS The top grid electrode applies 0V voltage, and the current flowing between the source electrode and the drain electrode is different according to the strength and the speed of pulse pulsation. Wherein the sensitivity of the pressure sensor is defined as: taking the same Vgs at each pressure, the Ids will be different, and therefore the different Ids will be the result of the change in the pressure potential, and thus a function between the value of Ids and the value of pressure can be obtained, with the slope of the function being the sensitivity.

In the example shown in fig. 6, we test the sensitivity curve obtained on the basis of the value of Ids, with Vgs =0V as an example.

In some embodiments, the channel current of the test may be in sampling mode. For example, when a voltage of 0V is applied, the current flowing between the source electrode and the drain electrode changes with the pulsation of the pulse, and is related to the time, one current value is acquired every 0.04 seconds, and a total of 245 Ids points are acquired in a 6-second time period, that is, a curve for detecting the pulse pressure reflects the pulse and the fluctuation thereof under different pulse conditions.

Comparison of tests

The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction in traditional Chinese medicine prepared in the previous embodiment was used as a basis for testing and analysis.

Dynamic forces were tested using an electrokinetic displacement stage and Keithley 2636, and the current flowing between the source and drain electrodes was different under different applied pressures. The pressure was measured at room temperature by a pressure sensor at pressure values of 0.5, 1, 1.8, 2.9, 4.7N, respectively, as shown in fig. 5.

The current Ids flowing between the required source electrode and the required drain electrode under the same gate voltage is drawn, and the channel current Ids and the pressure value are drawn into a curve, as shown in fig. 6, the abscissa is the pressure value, the ordinate is the channel current Ids, and the slope of the formed curve is the detection response sensitivity of the sensor.

As shown in FIG. 6, the pressure sensor has a sensitivity of up to 0.176/N and exhibits high sensitivity over a wide pressure range, while exhibiting good linearity and wide-range stability. At a pressure value of 2.9N, the current Ids flowing between the source electrode and the drain electrode obtained by the test was 213nA, as shown in fig. 7. In the transfer curve, each voltage has a corresponding current value, and at a pressure value of 2.9N, the voltage obtained by the test is-0.97V, as shown in FIG. 8 a. The gate voltage change-0.75V was obtained by equivalent circuit analysis, and the current Ids flowing between the corresponding source and drain electrodes in the transfer curve was 213nA, as shown in FIG. 8 b.

In combination with the schematic diagram of the continuous real-time detection result shown in fig. 7, high stability is shown in the continuous detection process of the same pressure value.

In the example shown in fig. 9, the pulse is tested in a calm state, the pulse beats once in about one second, and the amplified pulse signal clearly shows the characteristic peaks of the peripheral arterial waveform, which contain important biomedical and physiological information such as arteriosclerosis, coronary artery disease, myocardial infarction, and the like.

It is thus clear that, based on the utility model discloses a carbon base field effect transistor pressure sensor for traditional chinese medical science pulse manifestation reappears, adopt pulse sensing subassembly and CNT-FET type sensing subassembly to constitute a plurality of independent passageways on the one hand and simulate the pulse process, realize pulse manifestation simulation and pulse manifestation reappear, solved traditional chinese medical science pulse taking diagnosis and probably appear misdiagnosis and the inefficiency problem, realized pulse manifestation reappears, obtain visual result, make things convenient for traditional chinese medical science diagnosis and teaching, promoted traditional chinese medical science to inherit simultaneously. And simultaneously, the utility model discloses a pressure sensor that semiconductor technology comes the preparation realizes high miniaturization and integration, has avoided using the unable problem of continuous monitoring pulse that huge instrument brought.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention. The present invention is intended to cover by those skilled in the art various modifications and adaptations of the invention without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention is subject to the claims.

Claims (12)

1. A carbon-based field effect transistor pressure sensor for Chinese medicine pulse manifestation recurrence is characterized by comprising three independent pulse manifestation recurrence channels (100), wherein each pulse manifestation recurrence channel (100) is composed of a pulse sensing component (110) and a CNT-FET type sensing component (120) which is correspondingly arranged;

the CNT-FET type sensing component (120) of each pulse condition recurrence channel is electrically connected with the pulse sensing component (110) directly acting on the skin surface of a human body through a conductive medium, the pulse sensing component (110) is provided with a finger simulation channel (72) used for sensing pulse conditions and changes thereof, the sensing output of the finger simulation channel (72) is transmitted to the corresponding CNT-FET type sensing component (120) through the conductive medium, and the CNT-FET type sensing components (120) of the three pulse condition recurrence channels rapidly output response data of the corresponding channels.

2. The carbon-based field effect transistor pressure sensor for pulse manifestation recurrence of traditional Chinese medical science of claim 1, wherein the pulse sensing component (110) is composed of a piezoelectric material (60), a lower electrode (50), an upper electrode (51), a finger simulation channel (72) and an air tube (80);

the CNT-FET type sensing component (120) is composed of a silicon-based substrate (10), a CNT channel layer (20), a dielectric layer (30), a source electrode (40), a drain electrode (41), and a top gate electrode (42).

3. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medical science according to claim 2, wherein the silicon-based substrate (10) defines a first surface and an opposite second surface, with the first surface being a subsequently prepared growth surface;

the CNT channel layer (20) is positioned on a first surface of the silicon-based substrate (10) and is positioned between the source electrode (40) and the drain electrode (41);

forming a CNT channel layer (20) in the channel region by etching the CNT thin film located between the source electrode (40) and the drain electrode (41);

a dielectric layer (30) on an upper surface of the CNT channel layer (20);

the source electrode (40) and the drain electrode (41) are positioned at two sides of the dielectric layer (30) and the CNT channel layer (20), and the source electrode (40) and the drain electrode (41) are oppositely arranged and are arranged in a spaced mode;

the top gate electrode (42) is positioned on one side of the dielectric layer (30) far away from the silicon-based substrate (10), and the top gate electrode (42) is not in contact with the source electrode (40), the drain electrode (41) and the CNT channel layer (20).

4. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medical science of claim 3, wherein the CNT channel layer (20) is made of a mesh-like carbon nanotube with a certain thickness, and the thickness is controlled to be 0.5-2nm.

5. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medical science according to claim 3, wherein the dielectric layer (30) is yttria with a thickness of 6-10nm.

6. The carbon-based field effect transistor pressure sensor for pulse manifestation recurrence in traditional Chinese medicine of claim 3, wherein the source electrode (40) and the drain electrode (41) are both strip-shaped gold electrodes with the same thickness, the thickness is 60-80nm, the length is more than 30 μm, and the width is more than 5 μm.

7. The carbon-based field effect transistor pressure sensor for pulse manifestation repetition in traditional Chinese medicine according to claim 3, wherein the top gate electrode (42) is a strip-shaped gold electrode, the thickness of the top gate electrode (42) is 30-50nm, and the length is more than 1200 um.

8. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medical science according to any one of claims 3 to 7, wherein in each pulse manifestation reproduction channel, the piezoelectric material (60) defines an upper surface and a lower surface;

the lower electrode (50) and the upper electrode (51) are respectively positioned on the lower surface and the upper surface of the piezoelectric material (60); the lower electrode (50) and the upper electrode (51) are both of a thin-layer structure;

the lower electrode (50) and the source electrode (40) can be electrically connected through a first medium (90);

the upper electrode (51) and the top gate electrode (42) can be electrically connected through a second medium (91);

the finger simulation channel (72) is positioned on the surface of the upper electrode (51);

the air pipe (80) is communicated into the finger simulation channel (72) and is used for introducing air into the finger simulation channel (72) or exhausting air from the finger simulation channel (72);

in each pulse condition recurrence channel, the flow and volume of air introduced into the finger simulation channel (72) through the air pipe (80) are controlled, so that the internal pressure of the finger simulation channel (72) is controlled, and the internal pressure is downwards applied to the piezoelectric material (60) and the lower electrode (50) so as to act on pulse taking positions on the surface of a human body.

9. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medical science of claim 8, wherein each finger simulation channel (72) is independent and isolated from each other such that each finger simulation channel (72) is independently air pressure controlled.

10. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medical science of claim 8, wherein the piezoelectric material (60), the lower electrode (50) and the upper electrode (51) are all wrapped by PET, wherein the thickness of PET is 25-50um.

11. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medicine according to claim 8, wherein the finger simulation channel (72) comprises a first layer of PDMS (70) with a thin layer structure and a second layer of PDMS (71) with a concave microstructure, the first layer of PDMS (70) with the thin layer structure is positioned on the upper surface of the upper electrode (51), the second layer of PDMS (71) with the concave microstructure is positioned on the upper surface of the first layer of PDMS (70), the first layer of PDMS (70) and the second layer of PDMS (71) are bonded together to form the finger simulation channel (72), and a cavity is formed inside the finger simulation channel (72);

the pressure of the cavity inside the finger simulation channel (72) is changed by introducing gas into the cavity, so that the pulse taking of traditional Chinese medicine is simulated.

12. The carbon-based field effect transistor pressure sensor for pulse manifestation reproduction of traditional Chinese medical science of claim 11, wherein the concave microstructure of the second layer of PDMS (71) is a strip-shaped concave structure.

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