CN112268942A - Micro-nano sensing device, preparation method thereof and pH value detection method - Google Patents
Micro-nano sensing device, preparation method thereof and pH value detection method Download PDFInfo
- Publication number
- CN112268942A CN112268942A CN202010949639.XA CN202010949639A CN112268942A CN 112268942 A CN112268942 A CN 112268942A CN 202010949639 A CN202010949639 A CN 202010949639A CN 112268942 A CN112268942 A CN 112268942A
- Authority
- CN
- China
- Prior art keywords
- micro
- sensing device
- platinum
- nano
- electrode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/28—Electrolytic cell components
- G01N27/30—Electrodes, e.g. test electrodes; Half-cells
- G01N27/302—Electrodes, e.g. test electrodes; Half-cells pH sensitive, e.g. quinhydron, antimony or hydrogen electrodes
Abstract
The application provides a receive sensing device a little for the pH value of on-line measuring water, include: a glass substrate and a silicon substrate which are formed by anodic bonding and packaging, wherein a reference electrode is arranged on the glass substrate; a liquid storage tank and a micro-nano hole communicated with the liquid storage tank are formed in the silicon substrate and used for stabilizing the reference electrode; the silicon substrate is further provided with a platinum counter electrode and a hydrogen ion sensitive field effect transistor, the platinum counter electrode and the hydrogen ion sensitive field effect transistor form a pH value measuring circuit, the hydrogen ion sensitive field effect transistor is used for detecting output voltage, and the pH value of the water body is determined according to the difference value of the output voltage and the reference electrode. The application also provides a preparation method of the micro-nano sensing device and a pH value detection method. Through the application, the efficiency of pH value on-line measurement can be improved.
Description
Technical Field
The invention relates to the technical field of sensors, in particular to a micro-nano sensing device, a preparation method thereof and a pH value detection method.
Background
With the requirement of the environment detection field for large-scale measurement of environment basic parameters, online detection of pH value is particularly important. Among many types of pH detection sensors, Ion Sensitive Field Effect Transistors (ISFETs) have advantages of small size, high sensitivity, fast response, miniaturization, easy integration, and the like, and are gradually applied to online monitoring systems in the fields of biotechnology, food, pharmaceutical industry, water quality detection, and the like. However, the conventional Ion Sensitive Field Effect Transistor (ISFET) has the disadvantages of self-drift and hysteresis, which affect the detection of pH.
Therefore, it is necessary to provide a pH detection device capable of improving the efficiency of online pH measurement.
Disclosure of Invention
In view of this, it is necessary to provide a micro-nano sensing device, a manufacturing method thereof, and a pH value detection method, which can improve the efficiency of online pH value measurement.
The first aspect of the embodiments of the present application provides a micro-nano sensing device for detecting the pH value of a water body on line, including: a glass substrate and a silicon substrate which are formed by anodic bonding and packaging, wherein a reference electrode is arranged on the glass substrate; a liquid storage tank and a micro-nano hole communicated with the liquid storage tank are formed in the silicon substrate and used for stabilizing the reference electrode; the silicon substrate is further provided with a platinum counter electrode and a hydrogen ion sensitive field effect transistor, the platinum counter electrode and the hydrogen ion sensitive field effect transistor form a pH value measuring circuit, the hydrogen ion sensitive field effect transistor is used for detecting output voltage, and the pH value of the water body is determined according to the difference value of the output voltage and the reference voltage of the reference electrode.
Further, in the micro-nano sensing device provided by the present application, the hydrogen ion sensitive field effect transistor includes: the platinum source electrode, the platinum grid electrode and the platinum drain electrode are arranged on the upper surface of the silicon substrate, the conductive channel layer is arranged inside the silicon substrate, and the surface of the platinum grid electrode is coated with a hydrogen ion sensitive material.
Further, in the above-mentioned micro-nano sensing device that this application provided, hydrogen ion sensitive material includes ruthenium oxide, ruthenium oxide's thickness is 1-2um, ruthenium oxide be used for with hydrogen ion in the water takes place electrochemical reaction, arouses the change of current carrier concentration in the conduction channel layer, thereby makes the platinum source electrode with the output voltage between the platinum drain electrode changes.
Further, in the micro-nano sensing device provided by the application, oxide layers are arranged on the upper surface and the lower surface of the silicon substrate.
Further, in the above-mentioned sensing device that receives a little that this application provided, install in the liquid storage tank the reference electrode, it encapsulates in advance to be equipped with potassium chloride saturated solution in the liquid storage tank the reference electrode, a plurality of micro-nano holes have still been seted up on the liquid storage tank for carry out ion transmission, thereby guarantee the stability of reference electrode.
Further, in the micro-nano sensing device provided by the application, the micro-nano holes are through holes which are formed by photoetching patterning and wet etching processes and have a size of a nano pole, and the number of the micro-nano holes is 1-4.
Further, in the micro-nano sensing device provided by the application, the reference electrode comprises a silver layer prepared on the glass substrate and a silver chloride layer obtained by treating the surface of the silver layer with hydrochloric acid.
The second aspect of the embodiment of the present application provides a preparation method based on the micro-nano sensing device, where the preparation method includes:
selecting a silicon substrate with two polished and oxidized surfaces;
processing the silicon substrate by adopting a double-sided photoetching patterning process to prepare an anisotropic etching window, preparing a liquid storage tank by adopting a potassium hydroxide wet etching process, and forming a plurality of micro-nano holes by adopting photoetching patterning and wet etching processes;
preparing a platinum counter electrode, a platinum source electrode, a platinum grid electrode and a platinum drain electrode on the upper surface of the silicon substrate by adopting metal sputtering and lift-off processes;
sputtering a hydrogen ion sensitive material on the upper surface of the platinum grid electrode by adopting metal sputtering and oxidizing to obtain ruthenium oxide, thereby completing the preparation of the silicon substrate;
preparing a silver layer on a glass substrate by adopting metal sputtering and lift-off processes;
treating the surface of the silver layer by hydrochloric acid to obtain a silver chloride layer, and finishing the preparation of the glass substrate;
and carrying out anodic bonding packaging on the silicon substrate and the glass substrate which are prepared to form the micro-nano sensing device.
The third embodiment of the present application further provides a pH value detection method, in which the micro-nano sensing device is applied, and the pH value detection method includes:
acquiring output voltage of the micro-nano sensing device and reference voltage corresponding to the reference electrode;
detecting whether the output voltage of the micro-nano sensing device meets a preset stability requirement or not;
when the detection result shows that the output voltage of the micro-nano sensing device meets the preset stability requirement, calculating a voltage difference value between the output voltage and the reference voltage;
and determining the pH value of the water body to be detected according to the voltage difference value by traversing a preset mapping relation table of the voltage value and the hydrogen ion concentration.
Further, in the method for detecting a pH value provided by the present application, the step of obtaining an output voltage of the micro-nano sensing device includes:
detecting whether the ruthenium oxide on the surface of the platinum grid electrode reacts with hydrogen ions in a water body to generate a potential difference or not;
when the detection result is that the ruthenium oxide on the surface of the grid electrode reacts with hydrogen ions in a water body to generate a potential difference, acquiring the voltage between the platinum source electrode and the platinum drain electrode;
and calling an input operational amplifier to amplify the voltage to obtain the output voltage of the micro-nano sensing device.
The invention provides a micro-nano sensing device, a preparation method thereof and a pH value detection method, which are used for detecting the pH value of a water body on line.
Drawings
Fig. 1 is a schematic diagram of a micro-nano sensing device provided in an embodiment of the present application.
Fig. 2 is a measurement circuit diagram of a micro-nano sensing device provided in an embodiment of the present application.
Fig. 3 is an exploded view of a micro-nano sensing device provided in an embodiment of the present application.
Fig. 4 is a flowchart of a micro-nano sensing device-based manufacturing method provided in an embodiment of the present application.
Fig. 5 is a flowchart of a pH detection method provided in an embodiment of the present application.
Description of the main elements
Detailed Description
So that the manner in which the above recited objects, features and advantages of embodiments of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. In addition, the features of the embodiments of the present application may be combined with each other without conflict.
In the following description, numerous specific details are set forth to provide a thorough understanding of embodiments of the invention, some, but not all embodiments of the invention. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative effort belong to the protection scope of the embodiments of the present invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which embodiments of the present invention belong. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the embodiments of the invention.
The application provides a receive sensing device a little for the pH value of on-line measuring water, include: a glass substrate and a silicon substrate which are formed by anodic bonding and packaging, wherein a reference electrode is arranged on the glass substrate; a liquid storage tank and a micro-nano hole communicated with the liquid storage tank are formed in the silicon substrate and used for stabilizing the reference electrode; the silicon substrate is further provided with a platinum counter electrode and a hydrogen ion sensitive field effect transistor, the platinum counter electrode and the hydrogen ion sensitive field effect transistor form a pH value measuring circuit, the hydrogen ion sensitive field effect transistor is used for detecting output voltage, and the pH value of the water body is determined according to the difference value of the output voltage and the reference electrode.
The invention provides a micro-nano sensing device which is used for detecting the pH value of a water body on line, and the problems of charge loss, electrode surface polarization and the like of a reference electrode can be avoided by arranging a liquid storage tank and a micro-nano hole communicated with the liquid storage tank on a silicon substrate to stabilize the reference electrode, so that the defects of self-drift phenomenon, hysteresis effect and the like of a hydrogen ion sensitive field effect transistor are avoided, and the measurement efficiency of the pH value is improved.
Some embodiments of the present application will be described in detail below with reference to the accompanying drawings.
Referring to fig. 1, the present invention provides a micro-nano sensing device 100 for detecting a pH value of a water body on line, where the micro-nano sensing device 100 includes: a glass substrate 10 and a silicon substrate 20 formed by anodic bonding encapsulation, wherein a reference electrode 11 is arranged on the glass substrate 10; a liquid storage tank 21 and a micro-nano hole 22 communicated with the liquid storage tank 21 are formed in the silicon substrate 20 and used for stabilizing the reference electrode 11; the silicon substrate 20 is further provided with a platinum counter electrode 23 and a hydrogen ion sensitive field effect transistor 24, the platinum counter electrode 23 and the hydrogen ion sensitive field effect transistor 24 form a pH value measuring circuit, an output voltage is detected through the hydrogen ion sensitive field effect transistor 24, and the pH value of the water body is determined according to the difference between the output voltage and the reference voltage of the reference electrode 11.
The silicon substrate 20 is provided with oxide layers 25 on the upper surface and the lower surface, and the silicon substrate 20 can be protected in the wet etching process by the oxide layers 25. In one embodiment, the thickness of the oxide layer 25 may be set to 50nm, and the oxide layer 25 may be set to 50nm, thereby protecting the silicon substrate 20 and being suitable for mass production.
The hydrogen ion sensitive field effect transistor 24 includes a platinum source 241, a platinum gate 242, a platinum drain 243 and a conductive channel layer 244, wherein the platinum source 241, the platinum gate 242 and the platinum drain 243 are disposed on the upper surface of the silicon substrate 20, the conductive channel layer 244 is disposed inside the silicon substrate 20, and the conductive channel layer 244 is made of a silicon-based material. The electrode spacing of the platinum source 241, the platinum gate 242, the platinum drain 243 and the platinum counter electrode 23 is ensured not to be electrically broken down under the condition of power-up operation, and the specific length and width dimensions of the electrodes can be determined according to the overall dimensions of the micro-nano sensing device 100, which is not limited herein.
The hydrogen ion sensitive field effect transistor 24 further includes an input operational amplifier for amplifying the output voltage. By amplifying the output voltage, the measurement accuracy of the output voltage can be improved, and the measurement accuracy of the pH value can be further improved.
The surface of the platinum gate 242 is coated with a hydrogen ion sensitive material, the hydrogen ion sensitive material includes ruthenium oxide 2421, and the ruthenium oxide 2421 is configured to electrochemically react with hydrogen ions in the water body to cause a change in carrier concentration in the conductive channel layer 244, so that an output voltage between the platinum source 241 and the platinum drain 243 is changed. In one embodiment, the thickness of the ruthenium oxide 2421 is 1-2um, and illustratively, the thickness of the ruthenium oxide 2421 is 1um, 1.2um, 1.4um, 1.6um, 1.8um, and 2 um. The thickness of the ruthenium oxide 2421 is set to be 1-2um, so that the requirement on the detection precision of the pH value can be met, and the method is suitable for batch preparation.
Ruthenium oxide 2421 is selected as a hydrogen ion sensitive material, ruthenium oxide 2421 is more stable in a water environment, the service life is relatively longer, and the preparation process of ruthenium oxide 2421 is compatible with the preparation process of micro-nano sensing device 100, so that the preparation method is suitable for batch preparation.
The reference electrode 11 includes a silver layer 111 prepared on the glass substrate 10, and a silver chloride layer (AgCl layer) 112 obtained by treating the surface of the silver layer (Ag layer) 111 with hydrochloric acid. According to the application, the silver layer 111 is used as an electrode lead, conductive silver paste is adopted to be electrically connected with an external lead of the micro-nano sensing device 100 after being packaged, extra electrode leads are avoided, the production process can be simplified, and the problems that the service life of the micro-nano sensing device 100 is short, the use safety is low and the like due to the fact that the extra electrode leads are abraded can be reduced.
Establish in the liquid reserve tank 21 reference electrode 11, be equipped with potassium chloride saturated solution (KCL) in the liquid reserve tank 21 and encapsulate in advance reference electrode 11, a plurality of micro-nano holes 22 have still been seted up on the liquid reserve tank 21 for carry out ion transmission, thereby guarantee reference electrode 11's stability.
The micro-nano holes 22 are through holes with the size of a nano pole formed by photoetching patterning and wet etching processes, and the number of the micro-nano holes 22 is 1-4. The micro-nano holes 22 may be tapered micro-holes, the sizes of the outer wall aperture and the inner wall aperture of the tapered micro-holes are not limited, and in an embodiment, the outer wall aperture of the tapered micro-holes is larger than the inner wall aperture; in another embodiment, the pore size of the outer wall of the tapered micro-pore is smaller than the pore size of the inner wall. Because the conical micropores not only have the function of ion exchange, but also have the nanoscale pore diameter, the ion exchange rate is greatly reduced, the service time of a potassium chloride saturated solution can be effectively prolonged, the service life of the reference electrode 11 is obviously prolonged, and the service life of the micro-nano sensing device 100 is further obviously prolonged.
Referring to fig. 2, fig. 2 is a measurement circuit diagram of a micro-nano sensing device according to an embodiment of the present disclosure. 1 denotes a platinum counter electrode, 2 denotes a platinum grid, 3 denotes a reference electrode, 4 denotes an input operational amplifier, 5 denotes a power supply, and 6 denotes an output voltage test terminal. The platinum counter electrode 23 and the platinum grid 242 form a pH value measurement circuit, the platinum grid 242 is coated with a hydrogen ion sensitive material, namely ruthenium oxide 2421, the ruthenium oxide 2421 and hydrogen ions in a water body generate an electrochemical reaction to generate a potential difference, and the potential difference causes a carrier concentration change in the conductive channel layer 244 under the platinum grid 242 (the resistance of the conductive channel layer 244 changes therewith), so that an output voltage between the platinum source 241 and the platinum drain 243 changes. And taking the reference electrode 11 as a reference voltage, measuring to obtain a difference value between the output voltage and the reference voltage, calling an input operational amplifier to realize signal amplification output, outputting the voltage difference value by an output voltage test end, and measuring to obtain the pH value of the water body by inquiring the corresponding relation between the voltage difference value and hydrogen ions in the water body.
This application passes through hydrogen ion sensitive field effect transistor 24 can realize the signal amplification function, improves output voltage's measurement accuracy, and then improves the measurement accuracy of pH value.
Referring to fig. 3 and fig. 4 together, a method for manufacturing a micro-nano sensing device 100 according to an embodiment of the present application includes the following steps:
and S41, selecting a silicon substrate with double-sided polishing oxidation.
In an embodiment, the oxide layer 25 is disposed on both the upper surface and the lower surface of the silicon substrate 20, the thickness of the oxide layer 25 may be set to 50nm, and the oxide layer 25 may be disposed to protect the silicon substrate 20 and is suitable for batch manufacturing.
S42, preprocessing the silicon substrate by adopting a double-sided photoetching patterning process, preparing an anisotropic corrosion window, preparing a liquid storage tank by adopting a potassium hydroxide wet etching process, and forming a plurality of micro-nano holes by adopting photoetching patterning and wet etching processes.
In one embodiment, a photoresist is spin-coated on the oxide layer 25 of the silicon substrate 20, and a wet etching pattern is formed by photolithography to form an anisotropic etching window. Removing the oxide layer 25 by BOD corrosive liquid, and corroding for about 10 hours at 35 ℃ by standard potassium hydroxide (KOH) corrosive liquid to form a liquid storage tank 21, wherein the bottom of the liquid storage tank 21 is in a non-closed form. And then, performing secondary photoetching to form a micro-nano hole etching port, and further performing wet etching to prepare a micro-nano hole 22.
S43, preparing a platinum counter electrode, a platinum source electrode, a platinum grid electrode and a platinum drain electrode on the upper surface of the silicon substrate by adopting metal sputtering and lift-off processes.
In one embodiment, a photoresist is spin-coated on the oxide layer 25, a pattern is photo-etched, a thickness of 200nm Cr (chromium) +500nm Pt (platinum) is sputtered, and a Lift-off process is performed in acetone to remove the photoresist, thereby preparing the platinum counter electrode 23, the platinum source electrode 241, the platinum drain electrode 243, and the platinum gate electrode 242. The conductive channel layer 244 is generated by a bias applied to the platinum gate 242 during pH testing, and is not shown in fig. 3. In one embodiment, when the oxide layer 25 is spin coated with photoresist, a thickness of 200nm Cr (chromium) may be sputtered first, and then a thickness of 500nm Pt (platinum) may be sputtered subsequently. In other embodiments, the platinum gate 242 is fabricated on the silicon substrate 20 based on the MEMS fabrication process, and the platinum source 241 and the platinum drain 243 are fabricated by removing photoresist by the Lift-off process, so as to construct and form the hydrogen ion sensitive field effect transistor 24 as the working electrode for pH measurement.
And S44, sputtering a hydrogen ion sensitive material on the upper surface of the platinum grid electrode by adopting metal sputtering and oxidizing to obtain ruthenium oxide, thus completing the preparation of the silicon substrate.
In one embodiment, ruthenium metal with a thickness of 500nm is sputtered on the surface of the platinum gate 242 and oxidized to obtain RuOx, forming a hydrogen ion sensitive electrode.
S45, preparing a silver layer on the glass substrate by adopting metal sputtering and lift-off process.
In one embodiment, the Pyrex7714 glass substrate 10 is metal sputtered with Ag and patterned.
And S46, treating the surface of the silver layer by hydrochloric acid to obtain a silver chloride layer, and finishing the preparation of the glass substrate.
In one embodiment, the Ag/AgCl electrode is formed by treating a metallic Ag layer with a 1M hydrochloric acid (HCl) solution to produce AgCl.
S47, carrying out anodic bonding encapsulation on the silicon substrate and the glass substrate which are prepared to form the micro-nano sensing device.
In one embodiment, the silicon substrate 20 and the glass substrate 10 after the structure preparation are aligned and bonded by anodic bonding, wherein the bottom of the liquid storage 21 is sealed by the glass substrate 10, and the reference electrode 11 on the glass substrate 10 is disposed in the liquid storage 21. Through the method, the Ag/AgCl reference electrode with the buffer solution storage tank and the ion exchange nanochannel can be prepared, and the 3M KCl saturated solution can be added for practical testing.
According to the preparation method based on the micro-nano sensing device 100, the platinum counter electrode is combined with the hydrogen ion sensitive field effect transistor, and the hydrogen ion sensitive field effect transistor is used as an electric signal conversion element for electrochemical reaction, so that the measurement speed of the pH value can be improved due to the advantages of quick response time, high signal-to-noise ratio, easiness in miniaturization, good stability, good batch preparation consistency and the like of the hydrogen ion sensitive field effect transistor; in addition, the hydrogen ion sensitive field effect transistor can realize a signal amplification function, improve the measurement accuracy of output voltage and further improve the measurement accuracy of the pH value.
Referring to fig. 5, an embodiment of the present application further provides a pH value detection method, where the micro-nano sensing device 100 is used to detect a pH value of a water body, and specifically, the pH value detection method includes the following steps:
and S51, obtaining the output voltage of the micro-nano sensing device and the reference voltage corresponding to the reference electrode.
In an embodiment, according to the operating principle of the field effect transistor, the measured output voltage of the micro-nano sensing device 100 is directly proportional to the electrochemical reaction occurring on the platinum gate 242, that is, the hydrogen ion concentration in the water to be measured, so that the pH value of the water can be measured by measuring the output voltage of the field effect transistor. The step of acquiring the output voltage of the micro-nano sensing device 100 includes: detecting whether the ruthenium oxide 2421 on the surface of the platinum grid 242 reacts with hydrogen ions in a water body to generate a potential difference; when the detection result is that the ruthenium oxide 2421 on the surface of the platinum gate 242 reacts with hydrogen ions in a water body to generate a potential difference, acquiring the voltage between the platinum source 241 and the platinum drain 243; and calling an input operational amplifier to amplify the voltage to obtain the output voltage of the micro-nano sensing device 100.
The reaction process of the ruthenium oxide 2421 on the surface of the platinum gate 242 and hydrogen ions in the water body is as follows:
RuOx：
s52, detecting whether the output voltage of the micro-nano sensing device meets a preset stability requirement, and executing the step S53 when the detection result shows that the output voltage of the micro-nano sensing device meets the preset stability requirement.
In an embodiment, the micro-nano sensing device 100 can tend to balance and stabilize the output voltage within a measurement time of 10s, obtain a stable output voltage, and then start to measure the pH value of the water body. The micro-nano sensing device 100 provided by the application has the advantage of short response time for pH value measurement.
And S53, calculating a voltage difference value between the output voltage and the reference voltage.
In an embodiment, for realizing the measurement of high accuracy, reference voltage must be reliable and stable, this application through seted up the liquid storage tank on the silicon substrate and with the communicating micro-nano hole of liquid storage tank is used for stabilizing reference electrode can avoid reference electrode's charge loss, electrode surface polarization scheduling problem.
And S54, traversing a preset mapping relation table of the voltage value and the hydrogen ion concentration according to the voltage difference value, and determining the pH value of the water body to be detected.
In an embodiment, standard reagents with pH values of 3 to 10 are selected, the micro-nano sensing device 100 is called to test the series of standard reagents to obtain corresponding output voltage values, a preset mapping relation table of the voltage values and the hydrogen ion concentrations is prepared, and a corresponding relation curve of the voltage values and the pH values is drawn.
The application provides a pH value detection method, which combines a platinum counter electrode with a hydrogen ion sensitive field effect transistor, and because the hydrogen ion sensitive field effect transistor has the advantages of short response time, high signal-to-noise ratio, easiness in miniaturization and the like, on one hand, the pH value measurement speed can be improved, and on the other hand, the requirement of batch manufacturing can be met; in addition, the hydrogen ion sensitive field effect transistor can realize a signal amplification function, improve the measurement accuracy of output voltage and further improve the measurement accuracy of the pH value.
It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that suitable changes and modifications of the above embodiments are within the scope of the claimed invention as long as they are within the spirit and scope of the present invention.
Claims (10)
1. A micro-nano sensing device is used for detecting the pH value of a water body on line and is characterized by comprising: a glass substrate and a silicon substrate which are formed by anodic bonding and packaging, wherein a reference electrode is arranged on the glass substrate; a liquid storage tank and a micro-nano hole communicated with the liquid storage tank are formed in the silicon substrate and used for stabilizing the reference electrode; the silicon substrate is further provided with a platinum counter electrode and a hydrogen ion sensitive field effect transistor, the platinum counter electrode and the hydrogen ion sensitive field effect transistor form a pH value measuring circuit, the hydrogen ion sensitive field effect transistor is used for detecting output voltage, and the pH value of the water body is determined according to the difference value of the output voltage and the reference electrode.
2. The micro-nano sensing device according to claim 1, wherein the hydrogen ion sensitive field effect transistor comprises: the platinum source electrode, the platinum grid electrode and the platinum drain electrode are arranged on the upper surface of the silicon substrate, the conductive channel layer is arranged inside the silicon substrate, and the surface of the platinum grid electrode is coated with a hydrogen ion sensitive material.
3. The micro-nano sensing device according to claim 2, wherein the hydrogen ion sensitive material comprises ruthenium oxide, the thickness of the ruthenium oxide is 1-2um, and the ruthenium oxide is used for electrochemically reacting with hydrogen ions in the water body to cause the concentration of carriers in the conductive channel layer to change, so that the output voltage between the platinum source electrode and the platinum drain electrode changes.
4. The micro-nano sensing device according to claim 1, wherein oxide layers are arranged on both the upper surface and the lower surface of the silicon substrate.
5. The micro-nano sensing device according to claim 1, wherein the reference electrode is installed in the liquid storage tank, a potassium chloride saturated solution is installed in the liquid storage tank to pre-encapsulate the reference electrode, and the liquid storage tank is further provided with a plurality of micro-nano holes for ion transmission, so that stability of the reference electrode is ensured.
6. The micro-nano sensing device according to claim 5, wherein the micro-nano holes are through holes with a size of a nano pole formed by a photoetching patterning and wet etching process, and the number of the micro-nano holes is 1-4.
7. The micro-nano sensing device according to claim 1, wherein the reference electrode comprises a silver layer prepared on the glass substrate and a silver chloride layer obtained by treating the surface of the silver layer with hydrochloric acid.
8. A preparation method of a micro-nano sensing device based on any one of the claims 1 to 7, characterized by comprising the following steps:
selecting a silicon substrate with two polished and oxidized surfaces;
pretreating the silicon substrate by adopting a double-sided photoetching patterning process, preparing an anisotropic etching window, preparing a liquid storage tank by adopting a potassium hydroxide wet etching process, and forming a plurality of micro-nano holes by adopting photoetching patterning and wet etching processes;
preparing a platinum counter electrode, a platinum source electrode, a platinum grid electrode and a platinum drain electrode on the upper surface of the silicon substrate by adopting metal sputtering and lift-off processes;
sputtering a hydrogen ion sensitive material on the upper surface of the platinum grid electrode by adopting metal sputtering and oxidizing to obtain ruthenium oxide, thereby completing the preparation of the silicon substrate;
preparing a silver layer on a glass substrate by adopting metal sputtering and lift-off processes;
treating the surface of the silver layer by hydrochloric acid to obtain a silver chloride layer, and finishing the preparation of the glass substrate;
and carrying out anodic bonding packaging on the silicon substrate and the glass substrate which are prepared to form the micro-nano sensing device.
9. A pH value detection method is applied to the micro-nano sensing device according to any one of claims 1 to 7, and is characterized by comprising the following steps:
acquiring output voltage of the micro-nano sensing device and reference voltage corresponding to the reference electrode;
detecting whether the output voltage of the micro-nano sensing device meets a preset stability requirement or not;
when the detection result shows that the output voltage of the micro-nano sensing device meets the preset stability requirement, calculating a voltage difference value between the output voltage and the reference voltage;
and determining the pH value of the water body to be detected according to the voltage difference value by traversing a preset mapping relation table of the voltage value and the hydrogen ion concentration.
10. The pH value detection method according to claim 9, wherein the step of obtaining the output voltage of the micro-nano sensing device comprises:
detecting whether the ruthenium oxide on the surface of the platinum grid electrode reacts with hydrogen ions in a water body to generate a potential difference or not;
when the detection result is that the ruthenium oxide on the surface of the grid electrode reacts with hydrogen ions in a water body to generate a potential difference, acquiring the voltage between the platinum source electrode and the platinum drain electrode;
and calling an input operational amplifier to amplify the voltage to obtain the output voltage of the micro-nano sensing device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010949639.XA CN112268942A (en) | 2020-09-10 | 2020-09-10 | Micro-nano sensing device, preparation method thereof and pH value detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010949639.XA CN112268942A (en) | 2020-09-10 | 2020-09-10 | Micro-nano sensing device, preparation method thereof and pH value detection method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112268942A true CN112268942A (en) | 2021-01-26 |
Family
ID=74349951
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010949639.XA Pending CN112268942A (en) | 2020-09-10 | 2020-09-10 | Micro-nano sensing device, preparation method thereof and pH value detection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112268942A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117209101A (en) * | 2023-11-07 | 2023-12-12 | 河南睿嘉环保科技有限责任公司 | Industrial waste water purifying, detecting and discharging device |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070095664A1 (en) * | 2005-11-01 | 2007-05-03 | National Yunlin University Of Science And Technology | Biosensor containing ruthenium, measurement using the same and application thereof |
| TW200900690A (en) * | 2007-06-29 | 2009-01-01 | Univ Nat Sun Yat Sen | PH-ion selective field effect transistor (pH-ISFET) with a miniaturized silver chloride reference electrode |
| US20100301399A1 (en) * | 2009-05-26 | 2010-12-02 | Chang Gung University | Sensitive field effect transistor apparatus |
| WO2011040803A1 (en) * | 2009-09-29 | 2011-04-07 | Mimos Berhad | A reference electrode and a method thereof |
| US20120258560A1 (en) * | 2011-04-06 | 2012-10-11 | Shamsoddin Mohajerzadeh | Method and system for fabricating ion-selective field-effect transistor (isfet) |
| CN107941876A (en) * | 2017-11-29 | 2018-04-20 | 宁波大学 | Silver/silver chloride reference electrode and preparation method thereof |
| CN108459061A (en) * | 2017-11-29 | 2018-08-28 | 宁波大学 | A kind of silver/silver chloride reference electrode and preparation method thereof |
| CN108780060A (en) * | 2016-03-02 | 2018-11-09 | 学校法人早稻田大学 | Ion transducer, ion concentration assay method and electronic unit |
| CN109813778A (en) * | 2019-01-30 | 2019-05-28 | 宁波大学 | A kind of integrated micro-nano sensor and preparation method thereof |
| CN212341087U (en) * | 2020-09-10 | 2021-01-12 | 江苏中天科技股份有限公司 | Micro-nano sensing device |
-
2020
- 2020-09-10 CN CN202010949639.XA patent/CN112268942A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070095664A1 (en) * | 2005-11-01 | 2007-05-03 | National Yunlin University Of Science And Technology | Biosensor containing ruthenium, measurement using the same and application thereof |
| TW200900690A (en) * | 2007-06-29 | 2009-01-01 | Univ Nat Sun Yat Sen | PH-ion selective field effect transistor (pH-ISFET) with a miniaturized silver chloride reference electrode |
| US20100301399A1 (en) * | 2009-05-26 | 2010-12-02 | Chang Gung University | Sensitive field effect transistor apparatus |
| WO2011040803A1 (en) * | 2009-09-29 | 2011-04-07 | Mimos Berhad | A reference electrode and a method thereof |
| US20120258560A1 (en) * | 2011-04-06 | 2012-10-11 | Shamsoddin Mohajerzadeh | Method and system for fabricating ion-selective field-effect transistor (isfet) |
| CN108780060A (en) * | 2016-03-02 | 2018-11-09 | 学校法人早稻田大学 | Ion transducer, ion concentration assay method and electronic unit |
| CN107941876A (en) * | 2017-11-29 | 2018-04-20 | 宁波大学 | Silver/silver chloride reference electrode and preparation method thereof |
| CN108459061A (en) * | 2017-11-29 | 2018-08-28 | 宁波大学 | A kind of silver/silver chloride reference electrode and preparation method thereof |
| CN109813778A (en) * | 2019-01-30 | 2019-05-28 | 宁波大学 | A kind of integrated micro-nano sensor and preparation method thereof |
| CN212341087U (en) * | 2020-09-10 | 2021-01-12 | 江苏中天科技股份有限公司 | Micro-nano sensing device |
Non-Patent Citations (2)
| Title |
|---|
| ROZINA ABDUL RANI 等: "Operational of ISFET as a pH sensor by using signal modulated reference electrode", INTERNATIONAL CONFERENCE ON INFORMATION AND MULTIMEDIA TECHNOLOGY, pages 548 - 550 * |
| ZAN ZHANG 等: "Batch Fabrication of Miniaturized Ag/AgCl Reference Electrode With Ion Exchanging Micro-Nano-Pores by Silicon-Base Double-Side Anisotropic Etching Process", JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, vol. 28, no. 5, pages 817 - 823, XP011748748, DOI: 10.1109/JMEMS.2019.2936651 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117209101A (en) * | 2023-11-07 | 2023-12-12 | 河南睿嘉环保科技有限责任公司 | Industrial waste water purifying, detecting and discharging device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Suzuki et al. | Micromachined liquid-junction Ag/AgCl reference electrode | |
| US8784640B2 (en) | Amperometric electrochemical sensor and method for manufacturing same | |
| US9513247B2 (en) | Electrochemical sensor | |
| CN212341087U (en) | Micro-nano sensing device | |
| CN105954333A (en) | Gold nanobelt three-electrode sensor used for monitoring heavy metal and preparation method thereof | |
| KR101488438B1 (en) | Electrochemical gas sensor | |
| CN112268942A (en) | Micro-nano sensing device, preparation method thereof and pH value detection method | |
| CN108680628A (en) | Micro-nano sensor and preparation method thereof for detecting nutrient concentrations in water | |
| CN108845017B (en) | Flexible ion sensor based on tungsten diselenide | |
| GB2460130A (en) | Self calibrating reference electrode | |
| US7270736B2 (en) | Electrode system for electrochemical sensor | |
| Knoll et al. | Micromachined ion-selective electrodes with polymer matrix membranes | |
| KR20120126977A (en) | CNT-based three electrode system, fabrication of the same and electrochemical biosensor using the same | |
| Zhou et al. | Microfabricated thin-film microelectrode for amperometric determination of CO2 in the gas phase | |
| JP4620215B2 (en) | Diaphragm sensor | |
| Wang et al. | Research on a Miniature Multiparameter Water Quality Sensor Chip and a System with a Temperature Compensation Function | |
| US8410530B2 (en) | Sensitive field effect transistor apparatus | |
| KR100497463B1 (en) | Oxygen sensor | |
| KR100434759B1 (en) | Multi sensor for measuring pH/DO and apparatus using the sensor | |
| DE102007039706A1 (en) | Chemical sensor on diamond layers | |
| GB2162997A (en) | A fluoride ion sensitive field effect transistor | |
| JPH1090219A (en) | Galvanic cell type gas sensor | |
| JPH0529024A (en) | Hydrogen ion detecting element and lead acid battery provided with the same | |
| JP2861149B2 (en) | Reference electrode | |
| KR100747414B1 (en) | Residual chlorine sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |