CN114751368A - Preparation method of graphene oxide surface modified MEMS gas sensor chip - Google Patents
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
- B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B7/00—Microstructural systems; Auxiliary parts of microstructural devices or systems
- B81B7/02—Microstructural systems; Auxiliary parts of microstructural devices or systems containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS]
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B81—MICROSTRUCTURAL TECHNOLOGY
- B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
- B81B2201/00—Specific applications of microelectromechanical systems
- B81B2201/02—Sensors
- B81B2201/0292—Sensors not provided for in B81B2201/0207 - B81B2201/0285
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Abstract
The invention relates to the technical field of micro-nano sensors, in particular to a preparation method of an MEMS gas sensor chip with a graphene oxide surface modified, which comprises the steps of S1, preparing an MEMS substrate micro heating layer; s2, preparing an interdigital electrode of the MEMS substrate and printing a sensitive material; s3, preparing a polystyrene colloid single-layer film; and S4, preparing the graphene oxide surface modified MEMS gas sensor. Firstly, preparing an MEMS substrate micro heating layer, an interdigital electrode and sensitive material printing; then preparing a polystyrene colloid single-layer film template; and finally, transferring and attaching the graphene oxide to the sensitive material of the MEMS gas sensor from the precursor solution through template dipping-nondestructive transfer to form a layer of ultrathin and densely covered graphene oxide film, so that the high-sensitivity and anti-interference MEMS gas sensor is prepared, and the process is reliable and easy to realize, and has the potential of large-scale batch production.
Description
Technical Field
The invention relates to the technical field of micro-nano sensors, in particular to a preparation method of an MEMS gas sensor chip with a graphene oxide surface modified.
Background
With the increasing emphasis on environmental protection, people put higher demands on the detection of various toxic and harmful gaseous substances. The gas sensor is a sensor capable of detecting specific gas components, sensing the specific components in the gas to be detected, and analyzing and outputting the specific components through electric signal conversion. The earliest gas sensor is used in the scene of leakage alarm of combustible explosive gas to ensure safe production and life safety. In industrially developed countries, such as the united states, japan, germany, uk, and the like, gas sensor technologies have been developed rapidly, and have all developed into key technology industries with complete varieties and comprehensive technologies. Through gradual popularization and application, the existing gas sensor has very important application value in the fields of air pollution monitoring, industry, national defense, food safety, medical detection and the like.
Gas sensors are mainly classified into chemical reaction type, thermal conduction type, optical type, electrochemical type, contact combustion type, semiconductor type, and the like, depending on the analytical detection method. Among them, the semiconductor gas sensor is favored by people because of its advantages of high sensitivity, fast response speed, small volume, light weight, and easy compatibility with Si-based semiconductor process. In particular, semiconductor resistance type gas sensors having good performance and being compatible with silicon processes are gradually taking a leading position in industrial applications. As early as the beginning of the 20 th century, the phenomenon that the surface resistance of a semiconductor material changes after gas is adsorbed on the surface of a semiconductor metal oxide is discovered, so that the use of a Metal Oxide Semiconductor (MOS) as a gas sensor is promoted. With the continuous development of the technology level, people put higher requirements on the gas sensor. To meet the requirements of stronger response, higher selectivity, smaller size, higher sensitivity, lower power consumption, and easy integration, micro-electro-mechanical systems (MEMS) are introduced into the design process of gas sensors. Meanwhile, the rapid development and application of the screen printing technology enable the gas sensor to realize the printing of the gas sensitive material with the tiny size, and the MEMS gas sensor is pushed to the way of industrial production.
When the current MEMS gas sensor is used for detecting multi-component gas, the problem of gas cross interference often exists. Most of the existing solutions are to optimize the result by compensating and correcting the sensor array or to improve the selectivity of the sensitive material to the target gas by physically and chemically modifying the sensitive material, but the above methods have the problems of low measurement accuracy, easy poisoning of the sensitive material and the like. Another solution is to adsorb the interfering gas by attaching a porous adsorption film on the sensor, but there is still a problem of poor stability. Recently, graphene-based gas sensors have attracted strong attention. Graphene has a large specific surface area and significantly high carrier mobility, providing a higher sensing area and lower resistivity. Meanwhile, the graphene has the characteristic of low electrical noise, and the sensitivity to gas can be further improved. In addition, the graphene has excellent mechanical properties and flexibility, so that the graphene can be coated and attached as a film material.
At present, patent CN112162015A discloses an anti-gas interference MEMS gas sensor and a preparation method thereof, in the method, a separation membrane is added when the MEMS gas sensor is manufactured, and the pore diameter of a nano-channel of the separation membrane is smaller than the movement diameter of interfering gas molecules, so that the interfering gas molecules collide in the nano-channel of the separation membrane in a large amount and cannot pass through the separation membrane, thereby blocking the interfering gas and avoiding the influence of the interfering gas on sensitive materials in the sensor, but the addition of the separation membrane by a coating or printing process is difficult to achieve. Patent CN113092545A discloses a CuO/In-based alloy2O3The method for preparing the modified graphene MEMS gas sensor comprises the steps of preparing a single material step by step and preparing a composite material by one step of ultrasonic hydrothermal to obtain rGO CuO/In2O3The gas sensitive material can control and more accurately the proportion of single materials in the prepared composite material. Meanwhile, a brand new designed composite multilayer sensor chip structure is used as a supplement, so that the sensor chip has excellent working performance under the conditions of extremely small volume and extremely low power consumption. However, the preparation of the composite gas-sensitive material in the patent is complicated, and is not beneficial to the amplification production.
The invention provides a preparation method of a graphene oxide surface modified MEMS gas sensor chip, which combines the preparation of a micro/nano structure film with an MEMS substrate, adopts a template dipping-nondestructive transfer mode, and attaches the graphene oxide film on the MEMS substrate in situ; the prepared MEMS gas sensor has high sensitivity and anti-interference gas-sensitive characteristics, has the potential of large-scale mass production, and is a method for preparing the high-sensitivity anti-interference MEMS gas sensor with strong applicability.
Disclosure of Invention
The technical problem to be solved by the invention is how to provide a preparation method of an MEMS gas sensor chip with a modified graphene oxide surface, wherein a template dipping-nondestructive transfer mode is adopted, and a graphene oxide film is attached to an MEMS substrate in situ, so that a highly sensitive and anti-interference MEMS gas sensor is prepared, the process is reliable, the realization is easy, and the potential of large-scale batch production is realized.
The invention solves the technical problems through the following technical means:
a preparation method of a graphene oxide surface modified MEMS gas sensor chip comprises the following specific steps:
s1 preparation of MEMS substrate micro heating layer
After the monocrystalline silicon piece is cleaned by ultraviolet ozone, SiO grows on the front side of the monocrystalline silicon piece through thermal oxidation2Layer of SiO deposited in sequence on the side of a monocrystalline silicon wafer2Layer and Si3N4A layer; then SiO on the front side of the monocrystalline silicon wafer2Deposition of Al on the layer2O3Adhering the layer, and designing a mask through ion beam etching; then Al2O3Depositing a Pt/Ti layer on the adhesion layer, and obtaining a Pt electrode pattern and a micro-heating layer pattern through corrosion stripping; finally to SiO2/Si3N4Etching the composite layer to form an etching window, and finishing SiO in a tetramethylammonium hydroxide solution2/Si3N4Releasing the composite layer to prepare the MEMS micro heating layer substrate;
s2, preparing MEMS substrate interdigital electrode and printing sensitive material
Depositing on the front surface of the MEMS micro-heating layer substrate prepared in the waySiO2An insulating layer on the SiO layer2Depositing a Pt/Au layer on the insulating layer, and obtaining a Pt electrode pattern and a signal line pattern through a stripping process to form a Pt electrode and an interdigital electrode; then, screen printing a gas-sensitive film on the interdigital electrode, and etching a corrosion window on the gas-sensitive film, so that enough area can be released to expose the center area of the interdigital electrode and the supporting cantilever; exposing the SiO under the protection of photoresist2/Si3N4Completely etching the composite layer, etching the silicon substrate along the etching window by using a KOH solution to form an inverted trapezoidal insulating cavity, and preparing the MEMS substrate attached with the gas-sensitive film;
s3 preparation of polystyrene colloid single-layer film
The method comprises the following steps of (1) paving a deionized water film on a clean glass substrate, then injecting a uniformly dispersed polystyrene latex microsphere-ethanol mixed solution, and performing self-assembly on colloidal particles by diffusion on a gas-liquid interface; after the liquid on the glass substrate is evaporated, the polystyrene colloid single-layer film on the glass substrate can be obtained;
s4 preparation of graphene oxide surface modified MEMS gas sensor
Immersing the prepared glass substrate covered with the polystyrene colloid single-layer film into a graphene oxide solution, wherein the polystyrene colloid single-layer film floats on the surface of the solution; then using the MEMS substrate attached with the gas-sensitive film as a substrate, taking out the polystyrene colloid single-layer film in the solution, standing and drying the coated substrate, then removing the coated polystyrene colloid single-layer film at the Pt electrode, and annealing to burn off the polystyrene template to form a graphene oxide film; and finally, cutting the substrate to finish the preparation of the graphene oxide surface modified MEMS sensor chip.
Has the advantages that: firstly, preparing an MEMS substrate micro heating layer, an interdigital electrode and sensitive material printing; then preparing a polystyrene colloid single-layer film template; and finally, transferring and attaching the graphene oxide to the MEMS gas sensor sensitive material from the front flooding liquid through template dipping-nondestructive transfer to form a layer of ultrathin and densely covered graphene oxide film, wherein the process is reliable and easy to realize, and has the potential of large-scale batch production.
According to the method, the preparation of the micro/nano structure film is combined with the MEMS substrate, a template dipping-nondestructive transfer mode is adopted, the graphene oxide film is attached to the MEMS substrate in situ, the blocking effect of the graphene oxide film on interference gas improves the selectivity of the sensor, and the prepared MEMS gas sensor has high-sensitivity and anti-interference gas-sensitive characteristics.
Preferably, the crystal orientation of the monocrystalline silicon wafer in the step S1 is one or more of <100>, <101>, <110>, <111 >.
Preferably, the type of the monocrystalline silicon wafer is one of an N type and a P type.
Preferably, the thickness of the monocrystalline silicon piece is 200-400 μm.
Preferably, the thermal oxidation temperature of the single crystal silicon wafer in the step S1 is 1000-1200 ℃, and SiO is formed on the front surface of the silicon wafer2The thickness of the layer is 100-300 nm.
Preferably, the SiO in the step S12Layer and Si3N4The layer is obtained by low pressure chemical vapor deposition at a temperature of 600-800 deg.C2The thickness of the layer is 200-400nm, Si3N4The thickness of the layer was 400-600 nm.
Preferably, Al in step S12O3The adhesion layer is deposited by atomic layer deposition technology, and Al2O3The thickness of the adhesion layer is 10-20 nm.
Preferably, the thickness of the Pt/Ti layer in the step S1 is 100-300nm, and the pitch and width of the micro heating layer pattern are both 10 μm.
Preferably, the SiO in the step S12/Si3N4The layer etching adopts ion beam selective etching technology.
Preferably, the temperature for releasing the film in the step S1 is 60-80 ℃, and the concentration of the tetramethylammonium hydroxide solution is 20-30 wt%.
Preferably, the SiO in the step S22The insulating layer is deposited by plasma enhanced chemical vapor depositionObtained, and SiO2The thickness of the insulating layer is 400-800 nm.
Preferably, the thickness of the Pt/Au layer in step S2 is 100-300nm, and the finger width and the finger pitch of the interdigital electrodes are both 10 μm.
Preferably, the thickness of the gas-sensitive film in step S2 is 10 μm, and the gas-sensitive material in the gas-sensitive film is one or two of ZnO and SnO.
Preferably, the etching window in the step S2 is formed by forward lithography etching, and SiO is formed2/Si3N4The composite layer is etched by reactive ion.
Preferably, the polystyrene latex microsphere-ethanol mixed solution in the step S3 is injected by a micro-pipetting pump, and the injection speed is 10 to 20 μ L/min.
Preferably, the particle size of the polystyrene latex microsphere suspension used for preparing the polystyrene latex microsphere-ethanol mixed solution in the step S3 is 200-1000 nm.
Preferably, the volume ratio of the suspension of the polystyrene latex microspheres in the polystyrene latex microspheres-ethanol mixed solution in the step S3 to ethanol is 30-50: 50-30.
Preferably, the concentration of the graphene oxide solution in the step S4 is 0.1-0.5 mg/mL.
Preferably, the standing time of the film-coated substrate in the step S4 is 5-20 min.
Preferably, the drying temperature in the step S4 is 105 ℃ and the drying time is 0.5-2 h.
Preferably, the annealing temperature in the step S4 is 400 ℃, and the time is 1-3 h.
The invention has the advantages that:
1. firstly, preparing an MEMS substrate micro heating layer, an interdigital electrode and sensitive material printing; then preparing a polystyrene colloid single-layer film template; and finally, transferring and attaching the graphene oxide to the MEMS gas sensor sensitive material from the front flooding liquid through template dipping-nondestructive transfer to form a layer of ultrathin and densely covered graphene oxide film, wherein the process is reliable and easy to realize, and has the potential of large-scale batch production.
2. According to the method, the preparation of the micro/nano structure film is combined with the MEMS substrate, a template dipping-nondestructive transfer mode is adopted, the graphene oxide film is attached to the MEMS substrate in situ, the blocking effect of the graphene oxide film on interference gas improves the selectivity of the sensor, and the prepared MEMS gas sensor has high-sensitivity and anti-interference gas-sensitive characteristics.
Drawings
Fig. 1 is a schematic structural view of a MEMS gas sensor chip prepared in embodiment 2 of the present invention.
Fig. 2 is an SEM image of a graphene oxide coating film of the MEMS gas sensor chip prepared in embodiment 2 of the present invention.
Fig. 3 is an SEM image of a MEMS gas sensor chip prepared in example 2 of the present invention.
Description of reference numerals: 1. a monocrystalline silicon wafer; 2. a Pt electrode; 3. a support boom; 4. a micro heating layer; 5. an insulating layer; 6. a signal line; 7. a gas-sensitive film; 8. a graphene oxide film.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The application discloses a preparation method of a graphene oxide surface modified MEMS gas sensor chip, which comprises the following specific steps:
s1 preparation of MEMS substrate micro heating layer 4
After the 200-plus 400-micron-thickness monocrystalline silicon wafer 1 is cleaned by ultraviolet ozone, SiO grows on the front surface of the monocrystalline silicon wafer 1 by thermal oxidation at 1000-plus 1200 DEG C2Layer (100-2Layer (200-400nm) and Si3N4Layer (400-600 nm); then utilizing the atomic layer deposition technology to form SiO on the front surface of the monocrystalline silicon wafer 12Depositing Al on the layer2O3Adhering the layer (10-20nm), and designing a mask by ion beam etching; then Al2O3Depositing a Pt/Ti layer (100-300nm) on the adhesion layer, and obtaining a Pt electrode pattern and a micro-heating layer 4 pattern (the distance and the width of the micro-heating layer 4 are both 10 mu m) through corrosion stripping; finally to SiO2/Si3N4The composite layer is selectively etched by ion beam to form an etching window, and SiO is completed in a tetramethylammonium hydroxide solution (20-30 wt%) at 60-80 DEG C2/Si3N4Releasing the composite layer to prepare the MEMS micro heating layer substrate.
Wherein, the crystal orientation of the monocrystalline silicon piece 1 is one or more of <100>, <101>, <110>, <111>, and the type of the monocrystalline silicon piece 1 is one of N-type and P-type.
S2, preparing MEMS substrate interdigital electrode and printing sensitive material
Carrying out plasma enhanced chemical vapor deposition (SiO) on the front surface of the prepared MEMS micro-heating layer 4 substrate25(400-800nm) insulating layer and then SiO2Depositing a Pt/Au layer (100-300nm) on the insulating layer 5, obtaining a Pt electrode pattern and a signal line 6 pattern through a stripping process, and forming a Pt electrode 2 and an interdigital electrode (wherein the finger width and the finger distance of the interdigital electrode are both 10 μm); then, printing a gas-sensitive film 7(10 micrometers) on the interdigital electrode through a screen, and etching a corrosion window on the gas-sensitive film 7 by using forward photoetching to ensure that enough area can be released subsequently to expose the central area of the interdigital electrode and the supporting cantilever 3; using reactive ion etching to expose SiO under protection of photoresist2/Si3N4Completely etching the composite layer, etching the silicon substrate along the etching window by using a KOH solution to form an inverted trapezoidal insulating cavity, and preparing the MEMS substrate attached with the gas-sensitive film 7; wherein, the gas-sensitive material in the gas-sensitive film 7 is one or two compositions of ZnO and SnO.
S3 preparation of polystyrene colloid single-layer film
Paving deionized water films on a clean glass substrate, injecting uniformly dispersed polystyrene latex microsphere-ethanol mixed solution at the speed of 10-20 mu L/min by adopting a micro-pipetting pump, diffusing colloidal particles on a gas-liquid interface, and carrying out self-assembly, wherein the particle size of polystyrene latex microsphere suspension used for preparing the polystyrene latex microsphere-ethanol mixed solution is 200-1000nm, and the volume ratio of polystyrene latex microsphere suspension to ethanol in the polystyrene latex microsphere-ethanol mixed solution is 30-50: 50-30; and after the liquid on the glass substrate is evaporated, obtaining the polystyrene colloid single-layer film on the glass substrate.
S4 preparation of graphene oxide surface modified MEMS gas sensor
Immersing the prepared glass substrate covered with the polystyrene colloid single-layer film into 0.1-0.5mg/mL graphene oxide solution, wherein the polystyrene colloid single-layer film floats on the surface of the solution; then using the prepared MEMS substrate attached with the gas-sensitive film 7 as a substrate, taking out the polystyrene colloid single-layer film in the solution, standing the coated substrate for 5-20min, then transferring the coated substrate to a drying oven at 105 ℃ for drying for 0.5-2h, then removing the polystyrene colloid single-layer film covering the Pt electrode 2, removing the covering film covering the Pt electrode 2 by using a contraposition thimble device, annealing at 400 ℃ for 1-3h, burning off the polystyrene template to form a graphene oxide film 8; and finally, cutting the substrate to finish the preparation of the graphene oxide surface modified MEMS sensor chip.
The polystyrene latex microsphere suspension selected for use in the following examples was produced biologically as indicated by 10% solids.
Example 1
The embodiment of the application discloses a preparation method of a graphene oxide surface modified MEMS gas sensor chip, which comprises the following specific steps:
s1 preparation of MEMS substrate micro heating layer 4
The N type with the thickness of 300 mu m<100>After the monocrystalline silicon wafer 1 is cleaned by ultraviolet ozone, SiO grows on the front surface of the monocrystalline silicon wafer 1 by thermal oxidation at 1100 DEG C2Layer (200nm), SiO being deposited in succession on the lateral surface of a monocrystalline silicon wafer 1 by low-pressure chemical vapour deposition at 800 DEG C2Layer (400nm) and Si3N4Layer (600 nm); then utilizing the atomic layer deposition technology to form SiO on the front surface of the monocrystalline silicon wafer 12Depositing Al on the layer2O3Adhering a layer (10nm), and designing a mask by ion beam etching; then Al2O3Depositing a Pt/Ti layer (200nm) on the adhesion layer, and obtaining a Pt electrode pattern and a micro heating layer 4 pattern (the distance and the width of the micro heating layer 4 are both 10 mu m) through corrosion stripping; finally to SiO2/Si3N4The composite layer is selectively etched by ion beams to form an etching window, and SiO is finished in a tetramethylammonium hydroxide solution (25 wt%) at 80 DEG C2/Si3N4Releasing the composite layer to prepare the MEMS micro heating layer 4 substrate;
s2, preparing MEMS substrate interdigital electrode and printing sensitive material
Carrying out plasma enhanced chemical vapor deposition (SiO) on the front surface of the prepared MEMS micro-heating layer 4 substrate2Insulating layer 5(600nm), then SiO2Depositing a Pt/Au signal layer (200nm) on the insulating layer 5, obtaining a Pt electrode pattern and a signal line 6 pattern through a stripping process, and forming a Pt electrode 2 and an interdigital electrode (the finger width and the finger distance of the interdigital electrode are both 10 μm); then, a ZnO film (10 mu m) is screen-printed on the interdigital electrode, and a corrosion window is etched on the gas-sensitive film 7 by using forward photoetching, so that enough area can be released to expose the center area of the interdigital electrode and the supporting cantilever 3; using reactive ion etching to expose SiO under protection of photoresist2/Si3N4Completely etching the composite layer, etching the silicon substrate along the etching window by using a KOH solution to form an inverted trapezoidal insulating cavity, and preparing the MEMS substrate attached with the gas-sensitive film 7;
s3 preparation of polystyrene colloid single-layer film
The method comprises the following steps of (1) paving a deionized water film on a clean glass substrate, then injecting uniformly dispersed polystyrene latex microsphere-ethanol mixed liquor by using a micro-pipetting pump at the speed of 20 mu L/min, so that colloidal particles diffuse on a gas-liquid interface and are self-assembled, wherein the particle size of polystyrene latex microsphere suspension used for preparing the polystyrene latex microsphere-ethanol mixed liquor is 500nm, and the volume ratio of polystyrene latex microsphere suspension to ethanol in the polystyrene latex microsphere-ethanol mixed liquor is 30: 50; after the liquid on the glass substrate is evaporated, the polystyrene colloid single-layer film on the glass substrate can be obtained;
s4 preparation of graphene oxide surface modified MEMS gas sensor
Immersing the prepared glass substrate covered with the polystyrene colloid single-layer film into 0.1mg/mL graphene oxide solution, wherein the polystyrene colloid single-layer film floats on the surface of the solution; then using the prepared MEMS substrate attached with the gas-sensitive film 7 as a substrate, taking out the polystyrene colloid single-layer film in the solution, standing the coated substrate for 10min, then transferring the coated substrate to a drying oven at 105 ℃ for drying for 1h, then removing the coated polystyrene colloid single-layer film at the Pt electrode 2, removing the coated film at the Pt electrode 2 by using a contraposition ejector pin device, annealing at 400 ℃ for 2h, and burning off a polystyrene template to form a graphene oxide film 8; and finally, cutting the substrate to finish the preparation of the graphene oxide surface modified MEMS sensor chip.
Example 2
The embodiment of the application discloses a preparation method of a graphene oxide surface modified MEMS gas sensor chip, as shown in FIG. 1, comprising the following specific steps:
s1 preparation of MEMS substrate micro heating layer 4
The N type with the thickness of 300 mu m<100>After the monocrystalline silicon wafer 1 is cleaned by ultraviolet ozone, SiO grows on the front surface of the monocrystalline silicon wafer 1 by thermal oxidation at 1100 DEG C2Layer (200nm) of SiO deposited in succession on the lateral surface of a monocrystalline silicon wafer 1 by low-pressure chemical vapour deposition at 800 DEG C2Layer (400nm) and Si3N4A layer (600 nm); then utilizing the atomic layer deposition technology to form SiO on the front surface of the monocrystalline silicon wafer 12Deposition of Al on the layer2O3Adhering a layer (10nm), and designing a mask by ion beam etching; then Al2O3Depositing a Pt/Ti layer (200nm) on the adhesion layer, and obtaining a Pt electrode pattern and a micro heating layer 4 pattern (the distance and the width of the micro heating layer 4 are both 10 mu m) through corrosion stripping; finally to SiO2/Si3N4The composite layer is etched selectively by ion beamEtching the window, and completing SiO in tetramethylammonium hydroxide solution (25 wt%) at 80 deg.C2/Si3N4Releasing the composite layer to prepare the MEMS micro heating layer 4 substrate;
s2, preparing MEMS substrate interdigital electrode and printing sensitive material
Carrying out plasma enhanced chemical vapor deposition (SiO) on the front surface of the prepared MEMS micro-heating layer 4 substrate2Insulating layer 5(600nm), then SiO2Depositing a Pt/Au signal layer (200nm) on the insulating layer 5, obtaining a Pt electrode pattern and a signal line 6 pattern through a stripping process, and forming a Pt electrode 2 and an interdigital electrode (the finger width and the finger distance of the interdigital electrode are both 10 μm); then, printing a SnO film (10 mu m) on the interdigital electrode by a screen printing method, and etching a corrosion window on the gas-sensitive film 7 by using forward photoetching to ensure that enough area can be released subsequently to expose the center area of the interdigital electrode and the supporting cantilever 3; using reactive ion etching to expose SiO under protection of photoresist2/Si3N4Completely etching the composite layer, etching the silicon substrate along the etching window by using a KOH solution to form an inverted trapezoidal insulating cavity, and preparing the MEMS substrate attached with the gas-sensitive film 7;
s3 preparation of polystyrene colloid single-layer film
Paving deionized water films on a clean glass substrate, injecting uniformly dispersed polystyrene latex microsphere-ethanol mixed liquor by adopting a micro-liquid transfer pump at the speed of 15 mu L/min, diffusing colloid particles on a gas-liquid interface, and performing self-assembly, wherein the particle size of polystyrene latex microsphere suspension used for preparing the polystyrene latex microsphere-ethanol mixed liquor is 500nm, and the volume ratio of polystyrene latex microsphere suspension to ethanol in the polystyrene latex microsphere-ethanol mixed liquor is 35: 45; after the liquid on the glass substrate is evaporated, the polystyrene colloid single-layer film on the glass substrate can be obtained;
s4 preparation of graphene oxide surface modified MEMS gas sensor
Immersing the prepared glass substrate covered with the polystyrene colloid single-layer film into 0.25mg/mL graphene oxide solution, wherein the polystyrene colloid single-layer film floats on the surface of the solution; then using the MEMS substrate attached with the gas-sensitive film 7 as a substrate, taking out a polystyrene colloid single-layer film in the solution, standing the coated substrate for 10min, then transferring the coated substrate to an oven at 105 ℃ for drying for 1h, then removing the polystyrene colloid single-layer film at the Pt electrode 2, removing the coated film at the Pt electrode 2 by using a contraposition thimble device, annealing at 400 ℃ for 2h, and burning off a polystyrene template to form a graphene oxide film 8, as shown in FIG. 2; and finally, cutting the substrate to finish the preparation of the graphene oxide surface modified MEMS sensor chip, wherein an SEM image of the prepared MEMS gas sensor chip is shown in FIG. 3.
Example 3
The embodiment of the application discloses a preparation method of a graphene oxide surface modified MEMS gas sensor chip, which comprises the following specific steps:
s1 preparation of MEMS substrate micro heating layer 4
The N type with the thickness of 300 mu m<100>After the monocrystalline silicon wafer 1 is cleaned by ultraviolet ozone, SiO grows on the front surface of the monocrystalline silicon wafer 1 by thermal oxidation at 1100 DEG C2Layer (200nm) of SiO deposited in succession on the lateral surface of a monocrystalline silicon wafer 1 by low-pressure chemical vapour deposition at 800 DEG C2Layer (400nm) and Si3N4Layer (600 nm); then utilizing the atomic layer deposition technology to form SiO on the front surface of the monocrystalline silicon wafer 12Depositing Al on the layer2O3Adhering a layer (10nm), and designing a mask through ion beam etching; then Al2O3Depositing a Pt/Ti layer (200nm) on the adhesion layer, and obtaining a Pt electrode pattern and a micro heating layer 4 pattern (the distance and the width of the micro heating layer 4 are both 10 mu m) through corrosion stripping; finally to SiO2/Si3N4The composite layer is selectively etched by ion beams to form an etching window, and SiO is finished in a tetramethylammonium hydroxide solution (25 wt%) at 80 DEG C2/Si3N4Releasing the composite layer to prepare the MEMS micro heating layer 4 substrate;
s2, preparation of MEMS substrate interdigital electrode and printing of sensitive material
Carrying out plasma enhanced chemical vapor deposition (SiO) on the front surface of the prepared MEMS micro-heating layer 4 substrate2Insulating layer 5(600nm), then SiO2Depositing a Pt/Au signal layer (200nm) on the insulating layer 5, obtaining a Pt electrode pattern and a signal line 6 pattern through a stripping process, and forming a Pt electrode 2 and an interdigital electrode (the finger width and the finger pitch of the interdigital electrode are both 10 mu m); and then, screen printing a SnO and ZnO thin film (10 mu m) on the interdigital electrode, wherein the ratio of SnO: the ZnO molar ratio is 1:1, and a corrosion window is etched on the gas-sensitive film 7 by using forward photoetching, so that enough area can be released to expose the center area of the interdigital electrode and the supporting cantilever 3; using reactive ion etching to expose SiO under protection of photoresist2/Si3N4Completely etching the composite layer, etching the silicon substrate along the etching window by using a KOH solution to form an inverted trapezoidal insulating cavity, and preparing the MEMS substrate attached with the gas-sensitive film 7;
s3 preparation of polystyrene colloid single-layer film
Paving deionized water films on a clean glass substrate, injecting uniformly dispersed polystyrene latex microsphere-ethanol mixed liquor at the speed of 10 mu L/min by using a trace liquid transfer pump, diffusing colloid particles on a gas-liquid interface, and performing self-assembly, wherein the particle size of polystyrene latex microsphere suspension used for preparing the polystyrene latex microsphere-ethanol mixed liquor is 500nm, and the volume ratio of polystyrene latex microsphere suspension to ethanol in the polystyrene latex microsphere-ethanol mixed liquor is 50: 30; after the liquid on the glass substrate is evaporated, obtaining the polystyrene colloid single-layer film on the glass substrate;
s4 preparation of graphene oxide surface modified MEMS gas sensor
Immersing the prepared glass substrate covered with the polystyrene colloid single-layer film into 0.5mg/mL graphene oxide solution, wherein the polystyrene colloid single-layer film floats on the surface of the solution; then using the prepared MEMS substrate attached with the gas-sensitive film 7 as a substrate, taking out the polystyrene colloid single-layer film in the solution, standing the coated substrate for 10min, then transferring the coated substrate to a drying oven at 105 ℃ for drying for 1h, then removing the coated polystyrene colloid single-layer film at the Pt electrode 2, removing the coated film at the Pt electrode 2 by using a contraposition ejector pin device, annealing at 400 ℃ for 2h, and burning off a polystyrene template to form a graphene oxide film 8; and finally, cutting the substrate to complete the preparation of the graphene oxide surface modified MEMS sensor chip.
Comparative example 1
A comparative example describes a method for preparing a MEMS gas sensor chip, which is different from example 2 in that surface modification of graphene oxide is not performed, and specific steps thereof include:
s1, preparing the MEMS substrate micro heating layer 4
The N type with the thickness of 300 mu m<100>After the monocrystalline silicon wafer 1 is cleaned by ultraviolet ozone, SiO grows on the front surface of the monocrystalline silicon wafer 1 by thermal oxidation at 1100 DEG C2Layer (200nm) of SiO deposited in succession on the lateral surface of a monocrystalline silicon wafer 1 by low-pressure chemical vapour deposition at 800 DEG C2Layer (400nm) and Si3N4A layer (600 nm); then utilizing the atomic layer deposition technology to form SiO on the front surface of the monocrystalline silicon wafer 12Depositing Al on the layer2O3Adhering a layer (10nm), and designing a mask through ion beam etching; then Al2O3Depositing a Pt/Ti layer (200nm) on the adhesion layer, and obtaining a Pt electrode pattern and a micro heating layer 4 pattern (the distance and the width of the micro heating layer 4 are both 10 mu m) through corrosion stripping; finally to SiO2/Si3N4The composite layer is selectively etched by ion beams to form an etching window, and SiO is finished in a tetramethylammonium hydroxide solution (25 wt%) at 80 DEG C2/Si3N4Releasing the composite layer to prepare the MEMS micro-heating layer 4 substrate;
s2, preparation of MEMS substrate interdigital electrode and printing of sensitive material
Carrying out plasma enhanced chemical vapor deposition (SiO) on the front surface of the prepared MEMS micro-heating layer 4 substrate2Insulating layer 5(600nm), then SiO2Depositing a Pt/Au layer (200nm) on the insulating layer 5, obtaining a Pt electrode pattern and a signal line 6 pattern through a stripping process, and forming a Pt electrode 2 and an interdigital electrode (the finger width and the finger pitch of the interdigital electrode are both 10 mu m); then, a SnO thin film (10 mu m) is screen-printed on the interdigital electrode, and a corrosion window is etched on the gas-sensitive thin film 7 by using forward photoetching, so that enough area can be released subsequently to expose the interdigital electrodeA central region and a supporting cantilever 3; using reactive ion etching to expose SiO under protection of photoresist2/Si3N4Completely etching the composite layer, etching the silicon substrate along the etching window by using a KOH solution to form an inverted trapezoidal insulating cavity, and preparing the MEMS substrate attached with the gas-sensitive film 7;
s3 preparation of MEMS gas sensor
And cutting the MEMS substrate attached with the gas-sensitive film 7 to finish the preparation of the MEMS sensor chip.
And (3) testing the gas-sensitive performance of the device:
the MEMS sensor chips prepared in examples 1 to 3 and comparative example 1 were gold wire bonded to construct a sensor device required for gas-sensitive performance test, and the sensor device was subjected to gas-sensitive performance test.
The gas-sensitive performance of the device is tested by using a source surface level multi-channel gas-sensitive test platform (SMP-4) developed by solid physics of the institute of fertilizer-merging materials science of Chinese academy of sciences. Wherein the multimeter/dc power supply (agilent U3606A and U8002A) provides a voltage source and collects voltage signals. 100ppm gas or steam is injected into the test cavity from the injection port, two rotating fans with 300rpm are symmetrically distributed near the gas injection port, the gas in the cavity can be uniformly mixed within 0.1 second, and the resistance of the device can be changed due to the gas injection, so that the voltage change is reflected in a circuit. Signals were controlled and collected using LabVIEW software at a 20/sec acquisition rate. The tests were all carried out at a relative humidity of 60% RH at ambient temperature of 25 ℃. The results of the tests are shown in table 1.
Table 1 results of gas-sensitive property test of sensor devices in examples 1 to 3 and comparative example 1
As can be seen from the results in table 1, when the graphene oxide is modified and compounded, the response strength of the MEMS device to VOC molecules such as ethanol and acetone is reduced, and the response strength to hydrogen is enhanced. At the same time, the response speed of the devices of examples 1-3 to VOC molecules such as ethanol and acetone is also reduced. As can be seen from fig. 2, a layer of graphene oxide network structure film is attached to the surface of the sensitive layer of the device, and due to the existence of the network structure film of the layer of film, VOC molecules such as ethanol and acetone are difficult to pass through, so that the MEMS gas sensor modified by the graphene oxide surface has highly sensitive and anti-interference gas-sensitive characteristics.
The use principle and the advantages are as follows: firstly, preparing an MEMS substrate micro heating layer, an interdigital electrode and sensitive material printing; then preparing a polystyrene colloid single-layer film template; and finally, transferring and attaching the graphene oxide to the sensitive material of the MEMS gas sensor from the front-driving liquid through template dipping-nondestructive transfer to form a layer of ultrathin and densely covered graphene oxide film. The graphene oxide MEMS gas sensor prepared based on template dipping-nondestructive transfer has high sensitivity and anti-interference gas sensitivity, provides an idea for solving the problem of gas cross interference when the MEMS gas sensor detects multi-component gas, has the potential of large-scale batch production, and is a method for preparing the high-sensitivity anti-interference MEMS gas sensor with strong applicability.
While the present invention provides a novel concept and method, and many ways of implementing the same, it will be apparent to those skilled in the art that various modifications can be made to the embodiments and the generic principles defined herein may be applied to other embodiments without undue inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention based on the disclosure of the present invention.
Claims (10)
1. A preparation method of a graphene oxide surface modified MEMS gas sensor chip is characterized by comprising the following steps: the method comprises the following specific steps:
s1 preparation of MEMS substrate micro heating layer
After the monocrystalline silicon piece is cleaned by ultraviolet ozone, SiO grows on the front side of the monocrystalline silicon piece through thermal oxidation2Layer of SiO deposited in sequence on the side of a monocrystalline silicon wafer2Layer and Si3N4A layer; then SiO on the front surface of the monocrystalline silicon wafer2Depositing Al on the layer2O3Adhering the layer, and designing a mask through ion beam etching; then Al2O3Depositing a Pt/Ti layer on the adhesion layer, and obtaining a Pt electrode pattern and a micro-heating layer pattern through corrosion stripping; finally to SiO2/Si3N4Etching the composite layer to form an etching window, and finishing SiO in a tetramethyl ammonium hydroxide solution2/Si3N4Releasing the composite layer to prepare the MEMS micro-heating layer substrate;
s2, preparing MEMS substrate interdigital electrode and printing sensitive material
Depositing SiO on the front surface of the MEMS micro-heating layer substrate prepared by the method2Insulating layer on SiO2Depositing a Pt/Au layer on the insulating layer, and obtaining a Pt electrode pattern and a signal line pattern through a stripping process to form a Pt electrode and an interdigital electrode; then, printing a gas-sensitive film on the interdigital electrode through a screen, and etching a corrosion window on the gas-sensitive film, so that enough area can be released subsequently to expose the central area of the interdigital electrode and the supporting cantilever; exposing the SiO under the protection of photoresist2/Si3N4Completely etching the composite layer, etching the silicon substrate along the etching window by using a KOH solution to form an inverted trapezoidal insulating cavity, and preparing the MEMS substrate attached with the gas-sensitive film;
s3 preparation of polystyrene colloid single-layer film
Paving deionized water films on a clean glass substrate, injecting uniformly dispersed polystyrene latex microsphere-ethanol mixed solution, and performing self-assembly on colloidal particles in a gas-liquid interface; after the liquid on the glass substrate is evaporated, the polystyrene colloid single-layer film on the glass substrate can be obtained;
s4 preparation of graphene oxide surface modified MEMS gas sensor
Immersing the prepared glass substrate covered with the polystyrene colloid single-layer film into a graphene oxide solution, wherein the polystyrene colloid single-layer film floats on the surface of the solution; then using the MEMS substrate attached with the gas-sensitive film as a substrate, taking out the polystyrene colloid single-layer film in the solution, standing and drying the coated substrate, then removing the coated polystyrene colloid single-layer film at the Pt electrode, and annealing to burn off the polystyrene template to form a graphene oxide film; and finally, cutting the substrate to finish the preparation of the graphene oxide surface modified MEMS sensor chip.
2. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, wherein the method comprises the following steps: the crystal orientation of the monocrystalline silicon wafer in the step S1 is one or more of <100>, <101>, <110>, <111 >; the type of the monocrystalline silicon wafer is one of N type and P type; the thickness of the monocrystalline silicon piece is 200-400 mu m.
3. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, wherein the method comprises the following steps: the thermal oxidation temperature of the single crystal silicon wafer in the step S1 is 1000-1200 ℃, and SiO is formed on the front surface of the silicon wafer2The thickness of the layer is 100-300 nm.
4. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, wherein the method comprises the following steps: SiO in the step S12Layer and Si3N4The deposition temperature of the layer is 600-800 ℃, and SiO is2The thickness of the layer is 200-400nm, Si3N4The thickness of the layer is 400-600 nm; al (Al)2O3The adhesion layer is deposited by atomic layer deposition technology, and Al2O3The thickness of the adhesion layer is 10-20 nm; the thickness of the Pt/Ti layer is 100-300nm, and the pitch and width of the micro-heating layer pattern are both 10 μm.
5. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, characterized in that: the temperature for releasing the film in the step S1 is 60-80 ℃, and the concentration of the tetramethylammonium hydroxide solution is 20-30 wt%.
6. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, characterized in that: SiO in the step S22The thickness of the insulating layer is 400-800nm, the thickness of the Pt/Au layer is 100-300nm, and the finger width and the finger distance of the interdigital electrode are both 10 μm.
7. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, wherein the method comprises the following steps: the thickness of the gas-sensitive film in the step S2 is 10 μm, and the gas-sensitive material in the gas-sensitive film is one or two of ZnO and SnO.
8. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, wherein the method comprises the following steps: in the step S3, the polystyrene latex microsphere-ethanol mixed solution is injected by a micro-pipetting pump, and the injection speed is 10-20 mu L/min.
9. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, characterized in that: the particle size of the polystyrene latex microsphere suspension used for preparing the polystyrene latex microsphere-ethanol mixed solution in the step S3 is 200-1000nm, and the volume ratio of the polystyrene latex microsphere suspension to the ethanol in the polystyrene latex microsphere-ethanol mixed solution is 30-50: 50-30.
10. The method for preparing the graphene oxide surface modified MEMS gas sensor chip according to claim 1, characterized in that: the concentration of the graphene oxide solution in the step S4 is 0.1-0.5 mg/mL; standing the coated substrate for 5-20 min; drying at 105 deg.C for 0.5-2 hr; the annealing temperature is 400 ℃ and the time is 1-3 h.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102288644A (en) * | 2011-07-08 | 2011-12-21 | 中国科学院上海微系统与信息技术研究所 | Resistance gas sensor with four support cantilever beams and a four-layer structure and method |
| KR20140144362A (en) * | 2013-06-10 | 2014-12-19 | 서울대학교산학협력단 | Flexible transparent chemical sensors based on graphene oxide and method for preparing the same |
| CN104874387A (en) * | 2015-04-15 | 2015-09-02 | 大连理工大学 | Preparation method of ordered porous ZnO/graphene composite film |
| CN105891263A (en) * | 2016-06-28 | 2016-08-24 | 上海交通大学 | Micro-nano sphere-graphene gas sensor and preparation method thereof |
| RU196523U1 (en) * | 2019-11-19 | 2020-03-03 | федеральное государственное автономное образовательное учреждение высшего образования "Южный федеральный университет" (Южный федеральный университет) | GAS-SENSITIVE SENSOR BASED ON CARBON NANOSTRUCTURES |
| CN111458382A (en) * | 2020-04-16 | 2020-07-28 | 华南师范大学 | Room-temperature flexible graphene oxide ordered porous film sensor and preparation method and application thereof |
| CN112162015A (en) * | 2020-09-07 | 2021-01-01 | 天地（常州）自动化股份有限公司 | Gas interference resistant MEMS gas sensor and preparation method thereof |
| CN112179956A (en) * | 2020-09-29 | 2021-01-05 | 西安交通大学 | Preparation method of MEMS formaldehyde sensor based on aluminum-doped zinc oxide porous nano film |
| CN114014257A (en) * | 2021-10-25 | 2022-02-08 | 华中科技大学 | Preparation method and application of silicon-based MEMS gas sensor chip |
-
2022
- 2022-04-12 CN CN202210380844.8A patent/CN114751368A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102288644A (en) * | 2011-07-08 | 2011-12-21 | 中国科学院上海微系统与信息技术研究所 | Resistance gas sensor with four support cantilever beams and a four-layer structure and method |
| KR20140144362A (en) * | 2013-06-10 | 2014-12-19 | 서울대학교산학협력단 | Flexible transparent chemical sensors based on graphene oxide and method for preparing the same |
| CN104874387A (en) * | 2015-04-15 | 2015-09-02 | 大连理工大学 | Preparation method of ordered porous ZnO/graphene composite film |
| CN105891263A (en) * | 2016-06-28 | 2016-08-24 | 上海交通大学 | Micro-nano sphere-graphene gas sensor and preparation method thereof |
| RU196523U1 (en) * | 2019-11-19 | 2020-03-03 | федеральное государственное автономное образовательное учреждение высшего образования "Южный федеральный университет" (Южный федеральный университет) | GAS-SENSITIVE SENSOR BASED ON CARBON NANOSTRUCTURES |
| CN111458382A (en) * | 2020-04-16 | 2020-07-28 | 华南师范大学 | Room-temperature flexible graphene oxide ordered porous film sensor and preparation method and application thereof |
| CN112162015A (en) * | 2020-09-07 | 2021-01-01 | 天地（常州）自动化股份有限公司 | Gas interference resistant MEMS gas sensor and preparation method thereof |
| CN112179956A (en) * | 2020-09-29 | 2021-01-05 | 西安交通大学 | Preparation method of MEMS formaldehyde sensor based on aluminum-doped zinc oxide porous nano film |
| CN114014257A (en) * | 2021-10-25 | 2022-02-08 | 华中科技大学 | Preparation method and application of silicon-based MEMS gas sensor chip |
Non-Patent Citations (3)
| Title |
|---|
| LI NANXI 等: "Radiation enhancement by graphene oxide on microelectromechanical system emitters for highly selective gas sensing", ACS SENSORS, vol. 4, 16 September 2019 (2019-09-16), pages 2746 - 2753 * |
| 安飞 等: "三维石墨烯的制备及其在电阻型气体传感器领域的应用", 材料工程, vol. 48, no. 12, 10 November 2020 (2020-11-10), pages 24 - 35 * |
| 柏自奎 等: "金属氧化物微气体传感器制备技术的研究进展", 传感器技术, no. 09, 20 September 2005 (2005-09-20), pages 4 - 7 * |
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