CN112461413B

CN112461413B - Integrated micro-cantilever detection chip and preparation method thereof

Info

Publication number: CN112461413B
Application number: CN202011274453.5A
Authority: CN
Inventors: 张贺; 杨爽; 郑艳娜; 揣荣岩; 李新
Original assignee: Shenyang University of Technology
Current assignee: Shenyang University of Technology
Priority date: 2020-11-15
Filing date: 2020-11-15
Publication date: 2022-03-08
Anticipated expiration: 2040-11-15
Also published as: CN112461413A

Abstract

The invention belongs to the field of micro electro mechanical systems, and relates to an integrated micro-cantilever beam detection chip which comprises a substrate, wherein a detection pool bottom groove is formed inwards at the upper end of the substrate, a detection signal extraction circuit based on a Wheatstone bridge is arranged on the substrate, a capping is prepared at the upper end of the substrate, the substrate and the detection signal extraction circuit based on the Wheatstone bridge are fully covered by the capping, a micro-cantilever beam reference sensor and a micro-cantilever beam detection sensor of the detection signal extraction circuit based on the Wheatstone bridge are positioned in the detection pool formed by the capping and the detection pool bottom groove of the substrate, and two sides of the substrate and the capping are respectively combined to form a liquid inlet and a liquid outlet. The invention solves the problems of the traditional MEMS technology in integrating various and multifunctional devices such as electricity, machinery, biology, chemistry and the like and preparing a precise detection instrument at low cost.

Description

Integrated micro-cantilever detection chip and preparation method thereof

Technical Field

The invention belongs to the field of Micro-electro Mechanical Systems (MEMS), and relates to an integrated Micro-cantilever beam detection chip and a preparation method thereof.

Background

Although the volume and the integration degree of a detection instrument are improved to a certain degree by combining a micro cantilever beam and a micro total analysis system (μ TAS) chip in the prior art, the existing micro cantilever beam sensor takes silicon, silicon nitride and silicon oxide or compound as substrate materials, the preparation technology of the existing micro cantilever beam sensor is mostly from an MEMS process, and the steps of oxidation, etching, sputtering, photoetching and the like are complex in process and high in cost and need to be finished in an ultra-clean environment. And the technologies of micro-processing, soft printing, stamping, injection molding and the like on the surface of the polymer adopted in the preparation process of the mu TAS chip are not only as complicated, but also not ideal in compatibility with the MEMS process. The splitting of the preparation process causes that the existing micro-TAS design taking the micro-cantilever as the core is still limited to how to assemble the devices after miniaturization, and does not really consider each functional module as an organic whole, and the integrated design, optimization and realization are carried out from the height of the system.

In addition, when the microcantilever is used as the core of μ TAS for measuring biological and chemical changes, a specific modification layer is first coated on the surface of the free end. After the modification layer and a sample to be detected are subjected to selective adsorption or reaction, the micro-cantilever converts the generated molecular recognition signal into nanoscale mechanical deflection. Therefore, the sensitive modification process not only can expand the detection range of the micro-cantilever, but also is an important process for determining the sensitivity, the linear effective range, the response time, the reproducibility and the service life of the micro-cantilever. Before the silicon-based material micro-cantilever is sensitively modified by grafting, self-assembly or gene probe and other technologies, a gold film is generally evaporated on the surface of the silicon-based material, and the bonding capability of the silicon-based material and the modification layer is enhanced through a gold-sulfur bond formed between the gold film and the modification layer, so that the modification layer is prevented from falling off in the detection process. Then, by means of an operation platform including a capillary connection tube, a microscope, a cantilever support, a syringe and the like, after aligning the micro-cantilever with the capillary tube containing the reagent under the microscope, the micro-cantilever is soaked in the capillary tube, and the modification is completed through the intermolecular interaction. The whole modification process is time-consuming and labor-consuming, and has high requirements on the fineness and the proficiency of operators, and especially in the modification process of the array micro-cantilevers, mutual pollution among the micro-cantilevers can be caused by slight carelessness, and detection failure is caused. The novel MEMS technologies such as Inkjetprinting, Dip-Pen nanolithography, Nano-fountain probe and BioploumeTM can realize high-flux and high-accuracy modification of the silicon-based micro-cantilever sensor, but the purchase and use costs of the device are extremely high. Therefore, the preparation of the micro-cantilever and the μ TAS integration process steps are simplified, the production period is shortened, and the device cost is reduced while the high efficiency, high sensitivity, high specificity and high reliability modification are carried out, and a problem to be solved in the preparation process of the μ TAS chip taking the micro-cantilever as a core is urgently needed.

Disclosure of Invention

The purpose of the invention is as follows:

the invention provides an integrated micro-cantilever detection chip and a preparation method thereof to solve the problems in the prior art, so as to realize better combination of a micro-cantilever sensor and a mu TAS.

The technical scheme is as follows:

the integrated micro-cantilever detection chip comprises a substrate, wherein a detection pool bottom groove is inwards formed in the upper end of the substrate, a liquid inlet bottom groove and a liquid outlet bottom groove are respectively formed in two sides, located at the detection pool bottom groove, of the upper end of the substrate, and a Wheatstone bridge resistor R is further inwards formed in one side, located at the detection pool bottom groove, of the upper end of the substrate₁Bottom slot, Wheatstone bridge resistor R₂Bottom slot and Wheatstone bridge resistor R₃A bottom groove, a substrate biochemical passivation layer is arranged on the inner upper side of the detection tank bottom groove, a micro-cantilever beam reference sensor substrate is arranged on the inner upper side of the detection tank bottom groove, piezoresistive sensitive layer bottom grooves are arranged at the upper ends of the substrate biochemical passivation layer and the micro-cantilever beam reference sensor substrate, and a variable piezoresistive sensitive layer R of an electric bridge is prepared in each piezoresistive sensitive layer bottom groove_XWheatstone bridge resistance R₁A Wheatstone bridge resistor R is arranged in the bottom groove₁Wheatstone bridge resistance R₂A Wheatstone bridge resistor R is arranged in the bottom groove₂Wheatstone bridge resistance R₃A Wheatstone bridge resistor R is arranged in the bottom groove₃The upper end of the substrate is provided with a bridge driving positive wire, a bridge driving negative wire, a voltage output positive wire and a voltage output negative wire, a Wheatstone bridge resistor R₁Wheatstone bridge resistor R₂Wheatstone bridge resistor R₃Variable piezoresistive sensitive layer R of bridge_XA Wheatstone bridge-based detection signal extraction circuit consisting of a bridge driving positive wire, a bridge driving negative wire, a voltage output positive wire and a voltage output negative wire, and a Wheatstone bridge resistor R₁And a Wheatstone bridge resistor R₂Is commonly connected to one end of a bridge driving positive lead, the other end of the bridge driving positive lead is used for being connected to a driving voltage V_GPositive electrode of (2), Wheatstone bridge resistor R₃Variable piezoresistive sensitive layer R of bridge_XIs commonly connected to one end of a bridge-driven negative electrode lead, and the other end of the bridge-driven negative electrode lead is used for being connected to a driving voltage V_GOf negative electrode, WheatsBridge resistance R₁And a Wheatstone bridge resistor R₃The other end of the first resistor is connected with one end of a voltage output negative electrode lead, and a Wheatstone bridge resistor R₂Variable piezoresistive sensitive layer R of bridge_XThe other end of the voltage output negative electrode lead and the other end of the voltage output positive electrode lead are used for being connected to corresponding detection equipment, a micro-cantilever beam reference sensor seal is prepared at the upper end of a micro-cantilever beam reference sensor substrate, and the upper end surface of the micro-cantilever beam reference sensor substrate and a variable piezoresistive sensitive layer R of an electrical bridge are capped by the micro-cantilever beam reference sensor seal_XFull-coverage micro-cantilever beam reference sensor substrate, micro-cantilever beam reference sensor capping and variable piezoresistive sensitive layer R of bridge_XThe micro-cantilever beam reference sensor is formed, a capping biochemical sensitive layer is prepared at the upper end of a substrate biochemical passivation layer, and the capping biochemical sensitive layer is used for connecting the upper end surface of the substrate biochemical passivation layer and a variable piezoresistive sensitive layer R of an electric bridge_XFull-covering and capping biochemical sensitive layer, substrate biochemical passivation layer and variable piezoresistive sensitive layer R of bridge_XThe micro-cantilever detection sensor is formed, the upper end of the substrate is provided with a capping, and the capping comprises the substrate, a bridge driving positive lead, a bridge driving negative lead, a voltage output positive lead, a voltage output negative lead and a Wheatstone bridge resistor R₁Wheatstone bridge resistor R₂And a Wheatstone bridge resistor R₃The upper end of the liquid inlet is fully covered, the micro-cantilever beam reference sensor and the micro-cantilever beam detection sensor are positioned in a detection pool formed by the bottom of the detection pool of the top cover and the base, and the two sides of the base and the top cover are respectively combined into a liquid inlet and a liquid outlet.

Further, the base and the cap are both rigid polymeric materials.

Furthermore, the substrate biochemical passivation layer and the capping of the micro-cantilever beam reference sensor are both made of flexible polymer materials doped with specific insensitive components, and the capping biochemical sensitive layer is made of flexible polymer materials doped with specific biochemical sensitive components.

Further, the variable piezoresistive sensitive layer R of the bridge_XFor doping with piezoresistive sensitivityA flexible polymeric material of the component.

Further, the Wheatstone bridge resistor R₁Wheatstone bridge resistor R₂And a Wheatstone bridge resistor R₃Are both rigid polymeric materials doped with a resistive component.

Furthermore, the bridge driving positive wire, the bridge driving negative wire, the voltage output positive wire and the voltage output negative wire are all curable conductive ink.

Further, the bottom groove of the piezoresistive sensitive layer and the variable piezoresistive sensitive layer R of the bridge_XIs W-shaped.

Furthermore, one micro-cantilever beam detection sensor and an adjacent micro-cantilever beam reference sensor form a group of sensor detection units, and the physical dimensions, the main structure material performance, the piezoresistive sensitive layer material and the characteristic dimensions of the micro-cantilever beam detection sensor and the adjacent micro-cantilever beam reference sensor in each group of sensor detection units are all ensured to be consistent.

A preparation method of the integrated micro-cantilever detection chip comprises the following steps:

a) the rigid polymer material uses a 3D printing head to prepare a substrate of the integrated micro-cantilever detection chip, and the substrate is provided with a detection pool bottom groove, a liquid inlet bottom groove, a liquid outlet bottom groove and a Wheatstone bridge resistor R₁Bottom slot, Wheatstone bridge resistor R₂Bottom slot and Wheatstone bridge resistor R₃A bottom groove;

b) preparing a detection pool sacrificial layer substrate in a detection pool bottom groove by using a 3D printing head by using a water-soluble polymer material, wherein the height of the detection pool sacrificial layer substrate is consistent with the depth of the detection pool bottom groove, a micro-cantilever beam detection sensor bottom groove for placing a micro-cantilever beam detection sensor and a micro-cantilever beam reference sensor bottom groove for placing a micro-cantilever beam reference sensor are arranged on the detection pool sacrificial layer substrate, and a liquid inlet sacrificial layer and a liquid outlet sacrificial layer are also prepared by using the water-soluble polymer material on the liquid inlet bottom groove and the liquid outlet bottom groove;

c) flexible polymer material doped with specific insensitive component using 3D printing head to detect sensor bottom groove in micro-cantileverThe biochemical passivation layer of the substrate of the micro-cantilever beam detection sensor is prepared at the upper end of the micro-cantilever beam reference sensor, and the substrate of the micro-cantilever beam reference sensor is prepared at the upper end of the bottom groove of the micro-cantilever beam reference sensor; the biochemical passivation layer of the substrate and the micro-cantilever beam reference sensor substrate are both provided with a variable piezoresistive sensitive layer R for placing an electric bridge_XThe bottom groove of the piezoresistive sensitive layer;

d) flexible polymer material doped with piezoresistive sensitive component uses 3D printing head to prepare variable piezoresistive sensitive layer R of bridge of micro-cantilever beam detection sensor and micro-cantilever beam reference sensor in bottom groove of piezoresistive sensitive layer_X；

e) Rigid polymer material doped with resistive component using 3D printhead at wheatstone bridge resistance R₁Bottom slot, Wheatstone bridge resistor R₂Bottom slot and Wheatstone bridge resistor R₃Preparation of Wheatstone bridge resistor R in bottom groove₁Wheatstone bridge resistor R₂And a Wheatstone bridge resistor R₃；

f) Preparing a bridge driving positive lead, a bridge driving negative lead, a voltage output positive lead and a voltage output negative lead on a substrate by using a 3D printing head through the curable conductive ink;

g) preparing a micro-cantilever beam reference sensor capping of the micro-cantilever beam reference sensor by using a 3D printing head by using a flexible polymer material doped with a specific insensitive component;

h) preparing a capping biochemical sensitive layer of the micro-cantilever detection sensor by using a 3D printing head by using a flexible polymer material doped with a specific sensitive component;

i) the water-soluble polymer material uses a 3D printing head to prepare a detection pool sacrificial layer capping, the detection pool sacrificial layer capping completely covers the upper end surfaces of a detection pool sacrificial layer substrate, a liquid inlet sacrificial layer, a liquid outlet sacrificial layer, a micro-cantilever beam reference sensor capping and a capping biochemical sensitive layer, and the detection pool sacrificial layer capping covers the three weeks of the micro-cantilever beam reference sensor capping and the capping biochemical sensitive layer;

j) the rigid polymer material is used for preparing the capping of the integrated micro-cantilever beam detection chip by using a 3D printing head, and the substrate and the detection pool are sacrificed by cappingLivestock layer capping, bridge driving positive wire, bridge driving negative wire, voltage output positive wire, voltage output negative wire and Wheatstone bridge resistor R₁Wheatstone bridge resistor R₂And a Wheatstone bridge resistor R₃The upper end of the cover is fully covered, and the two sides of the substrate and the sealed top are respectively combined into a liquid inlet and a liquid outlet;

k) in a heatable ultrasonic cleaning machine, heating and vibrating cleaning are carried out simultaneously, a detection pool sacrificial layer substrate, a detection pool sacrificial layer capping, a liquid inlet sacrificial layer and a liquid outlet sacrificial layer are removed, and then a micro-cantilever detection sensor and a micro-cantilever reference sensor are released, so that an integrated micro-cantilever detection chip can be obtained.

The advantages and effects are as follows:

aiming at the problems of integration level, fusion degree, stability and the like caused by the splitting of a design method and the incompatibility of a preparation process in the process of combining a micro-cantilever sensor and a micro total analysis system chip, the invention designs a micro TAS chip integrating the functions of sample introduction, mixing, separation, enrichment and the like on the premise of taking a polymer micro-cantilever sensor working in a static piezoresistive mode as a link and ensuring environmental factors such as ion concentration, pH value, temperature and the like in the analysis process and realizing the rapid, real-time and accurate detection of trace samples. And then, on the basis of the advantages of customized processing, rapid forming, integrated production and the like of the mu TAS chip by fully utilizing the additive manufacturing technology, a composite electronic device embedding process suitable for integrated preparation and specific modification of the micro cantilever beam sensor is provided, so that all modules including the micro cantilever beam sensor and a sensitive modification layer thereof adopt polymers as substrate materials, and the process is expected to solve the problems of integration of multiple types and multifunctional devices such as electricity, machinery, biology, chemistry and the like in the traditional MEMS technology and low-cost preparation of a precision detection instrument. The invention is expected to obtain innovative achievements in the aspects of miniaturization, integrated design, manufacture, application and the like of precision instruments and accelerate the intelligent upgrading and reforming process of the equipment manufacturing industry. The integrated micro-cantilever detection chip can be used together with a micro-total analysis system chip to serve as a detection unit of the micro-total analysis system chip, and the biochemical analysis and detection capability of the integrated micro-cantilever detection chip is further improved.

Drawings

FIG. 1 is a top sectional view of an integrated micro-cantilever detection chip structure;

FIG. 2 shows an integrated micro-cantilever detection chip A₁-A₂A cross-sectional view;

FIG. 3 shows an integrated micro-cantilever detection chip B₁-B₂A cross-sectional view;

FIG. 4 is a schematic diagram of a detection bridge circuit of the integrated micro-cantilever detection chip;

FIG. 5 is a schematic view of a substrate structure process of the integrated micro-cantilever detection chip;

FIG. 6 is a schematic view of a process of a sacrificial layer of a detection cell of the integrated micro-cantilever detection chip;

FIG. 7 is a schematic view of a micro-cantilever substrate structure of the integrated micro-cantilever detection chip;

FIG. 8 is a schematic view of a process of a micro-cantilever piezoresistive sensitive layer of the integrated micro-cantilever detection chip;

FIG. 9 is a schematic diagram of a bridge resistance process of the integrated micro-cantilever detection chip;

FIG. 10 is a schematic view of a connection wire process of the integrated micro-cantilever detection chip;

FIG. 11 is a schematic view of a reference micro-cantilever capping structure of the integrated micro-cantilever detection chip;

FIG. 12 is a schematic view of a process for detecting a micro-cantilever capping structure of the integrated micro-cantilever detection chip;

FIG. 13 is a schematic diagram of a capping process of a sacrificial layer of a detection cell of the integrated micro-cantilever detection chip;

FIG. 14 is a schematic view of a capping structure of the integrated micro-cantilever detection chip;

FIG. 15 is a schematic view of the integrated micro-cantilever detection chip.

Description of reference numerals: 1. an integrated micro-cantilever detection chip; 2. a detection cell equipped with a micro-cantilever; 3. a liquid inlet; 4. a micro-cantilever detection sensor; 5. a micro-cantilever reference sensor; 6. a liquid outlet; 7. the bridge drives the positive conductor; 8. bridge driverA moving cathode lead; 9. a voltage output positive electrode lead; 10. a voltage output negative electrode lead; 11. wheatstone bridge resistor R₁(ii) a 12. Wheatstone bridge resistor R₂(ii) a 13. Wheatstone bridge resistor R₃(ii) a 14. Variable piezoresistive sensitive layer R of bridge_X(ii) a 15. The fixed end of the micro-cantilever beam detection sensor; 16.3D print head; 17. a first sensor detection unit; 18. a second sensor detection unit; 19. a specific sensitive component; 20. a sample to be tested; 21. interfering ions; 22. detecting the free end of the sensor by the micro-cantilever; 101. a substrate; 102. capping; 201. a detection pool bottom groove; 202. detecting a cell sacrificial layer substrate; 203. capping a sacrificial layer of the detection pool; 301. a liquid inlet bottom groove; 302. a liquid inlet sacrificial layer; 401. capping the biochemical sensitive layer; 402. a substrate biochemical passivation layer; 403. a micro-cantilever detection sensor bottom groove; 501. a micro-cantilever beam reference sensor bottom groove; 502. a microcantilever reference sensor substrate; 503. capping the micro-cantilever beam reference sensor; 601. a liquid outlet bottom groove; 602. a liquid outlet sacrificial layer; 1101. wheatstone bridge resistor R₁A bottom groove; 1201. wheatstone bridge resistor R₂A bottom groove; 1301. wheatstone bridge resistor R₃A bottom groove; 1401. and (4) a piezoresistance sensitive layer bottom groove.

The specific implementation mode is as follows:

the invention is further described below with reference to the accompanying drawings:

as shown in fig. 1, fig. 2 and fig. 3, an integrated micro-cantilever detection chip includes a substrate 101, a detection cell bottom groove 201 is formed in an upper end of the substrate 101, a liquid inlet bottom groove 301 and a liquid outlet bottom groove 601 are respectively formed in two sides of the detection cell bottom groove 201 at the upper end of the substrate 101, and a wheatstone bridge resistor R is further formed in one side of the detection cell bottom groove 201 at the upper end of the substrate 101₁Bottom slot 1101, Wheatstone bridge resistor R₂Bottom slot 1201 and Wheatstone bridge resistor R₃A bottom groove 1301, a substrate biochemical passivation layer 402 is arranged on the upper side inside the detection tank bottom groove 201, a micro-cantilever beam reference sensor substrate 502 is further arranged on the upper side inside the detection tank bottom groove 201, piezoresistive sensitive layer bottom grooves 1401 are arranged at the upper ends of the substrate biochemical passivation layer 402 and the micro-cantilever beam reference sensor substrate 502, and a variable piezoresistive sensitive layer R of an electric bridge is prepared in each piezoresistive sensitive layer bottom groove 1401_X14, pressure ofResistance sensitive layer bottom groove 1401 and variable resistance sensitive layer R of electric bridge_XThe W shape 14 has a resistance that varies over a wide range, as compared to straight, so that the fluctuation of av is large, and thus av is more easily detected. Wheatstone bridge resistor R₁A Wheatstone bridge resistor R is arranged in the bottom groove 1101₁11, Wheatstone bridge resistance R₂A Wheatstone bridge resistor R is arranged in the bottom slot 1201₂12, Wheatstone bridge resistance R₃A Wheatstone bridge resistor R is arranged in the bottom groove 1301₃13, a bridge driving positive wire 7, a bridge driving negative wire 8, a voltage output positive wire 9 and a voltage output negative wire 10 are arranged on the upper end of the substrate 101, and a Wheatstone bridge resistor R ₁11. Wheatstone bridge resistor R ₂12. Wheatstone bridge resistor R ₃13. Variable piezoresistive sensitive layer R of bridge _X14. The detection signal extraction circuit based on the Wheatstone bridge is composed of a bridge driving positive wire 7, a bridge driving negative wire 8, a voltage output positive wire 9 and a voltage output negative wire 10, and as shown in FIG. 4, a Wheatstone bridge resistor R₁11 and a Wheatstone bridge resistor R₂12 are connected together at one end to a bridge driving positive conductor 7, the other end of the bridge driving positive conductor 7 being connected to a driving voltage V_GPositive electrode of (2), Wheatstone bridge resistor R₃13 variable piezoresistive sensitive layer R of bridge_X14 are connected at one end to a bridge-driven negative conductor 8, and the other end of the bridge-driven negative conductor 8 is connected to a drive voltage V_GNegative pole of (1), Wheatstone bridge resistor R₁11 and a Wheatstone bridge resistor R₃The other end of the resistor 13 is connected with one end of the voltage output negative electrode lead 10, and a Wheatstone bridge resistor R₂12 and variable piezoresistive sensitive layer R of bridge_XThe other end of the 14 is connected with one end of a voltage output positive lead 9, the other end of a voltage output negative lead 10 and the other end of the voltage output positive lead 9 are used for being connected with corresponding detection equipment, and when the circuit works, a driving voltage V is provided for the bridge circuit through a bridge driving positive lead 7 and a bridge driving negative lead 8_GVariable piezoresistive sensitive layer R of bridge_X14 voltage fluctuation DeltaV generated by deformation is output through voltageThe pole lead 9 and the voltage output cathode lead 10 are sent to the respective detection devices. The upper end of the micro-cantilever beam reference sensor substrate 502 is provided with a micro-cantilever beam reference sensor capping 503, and the micro-cantilever beam reference sensor capping 503 is used for capping the upper end surface of the micro-cantilever beam reference sensor substrate 502 and the variable piezoresistive sensitive layer R of the bridge _X14 full coverage, micro-cantilever reference sensor substrate 502, micro-cantilever reference sensor capping 503 and variable piezoresistive sensitive layer R of bridge _X14, a capping biochemical sensitive layer 401 is prepared at the upper end of a substrate biochemical passivation layer 402, the capping biochemical sensitive layer 401 is used for covering the upper end surface of the substrate biochemical passivation layer 402 and a variable piezoresistive sensitive layer R of an electric bridge _X14 full-covered and capped biochemical sensitive layer 401, substrate biochemical passivation layer 402 and variable piezoresistive sensitive layer R of bridge _X14 form a micro-cantilever detection sensor 4, a capping 102 is prepared at the upper end of a substrate 101, and the capping 102 is used for connecting the substrate 101, a bridge driving positive lead 7, a bridge driving negative lead 8, a voltage output positive lead 9, a voltage output negative lead 10 and a Wheatstone bridge resistor R ₁11. Wheatstone bridge resistor R ₂12 and a Wheatstone bridge resistor R ₃13, and the micro-cantilever reference sensor 5 and the micro-cantilever detection sensor 4 are positioned in a detection cell formed by the capping part 102 and the detection cell bottom groove 201 of the substrate 101. The two sides of the substrate 101 and the capping 102 are combined to form a liquid inlet 3 and a liquid outlet 6, respectively.

Both the base 101 and the cap 102 are rigid polymeric materials. The substrate biochemical passivation layer 402 and the microcantilever reference sensor capping 503 are both flexible polymer materials doped with specific insensitive components, and the capping biochemical sensitive layer 401 is a flexible polymer material doped with specific biochemical sensitive components. The components of the capping biochemical sensitive layer 401 and the substrate biochemical passivation layer 402 can be adjusted correspondingly according to the change of the sample to be detected, so as to ensure the specific sensitivity of the micro-cantilever detection sensor 4. Variable piezoresistive sensitive layer R of bridge _X14 is a flexible polymeric material doped with a piezoresistive sensitive component. Wheatstone bridge resistor R ₁11. Wheatstone bridge resistor R ₂12 and a Wheatstone bridge resistor R ₃13 are all doped with resistor setsA partially rigid polymeric material. The bridge driving positive wire 7, the bridge driving negative wire 8, the voltage output positive wire 9 and the voltage output negative wire 10 are all curable conductive ink.

One micro-cantilever detection sensor 4 and the adjacent micro-cantilever reference sensor 5 form a group of sensor detection units, as shown in fig. 1, the detection cell 2 with the micro-cantilever is located in the substrate 101, the present embodiment has two groups of sensor detection units, which are respectively a first sensor detection unit 17 and a second sensor detection unit 18, and the overall dimensions, the performance of the main structure material, the material of the piezoresistive sensitive layer and the characteristic dimensions of the micro-cantilever detection sensor 4 and the adjacent micro-cantilever reference sensor 5 in each group of sensor detection units are all guaranteed to be consistent. In different detection units, the overall dimension, the main structure material performance, the piezoresistive sensitive layer material and the characteristic dimension of the micro-cantilever sensor can be designed in a customized way according to the characteristics of the sample to be detected and the specific detection principle. The number of the sensor detection units can be designed according to the customization of the components of the solution to be detected, so that the chip has the capability of high-flux parallel detection. The main body structures of the micro-cantilever beam detection sensor 4 and the micro-cantilever beam reference sensor 5 in the same detection unit adopt the same consumable material, and the consumable material is doped before printing to ensure that the consumable material has the performance of being sensitive to the specificity or insensitive to the specificity of a certain sample to be tested. The micro-cantilever detection sensor 4 is close to the Wheatstone bridge resistor R₃One side of 13 is a fixed end 15 of the micro-cantilever beam detection sensor, and the micro-cantilever beam detection sensor 4 is far away from a Wheatstone bridge resistor R₃On one side of 13 is the micro-cantilever detection sensor free end 22. The same applies to the micro-cantilever reference sensor 5.

The preparation method of the integrated micro-cantilever detection chip comprises the following steps:

a) as shown in fig. 5, a substrate 101 of the integrated micro-cantilever detection chip 1 is prepared by using a 3D print head 16 and using a rigid polymer material supporting fuse Fabrication (Fused Deposition Fabrication) or Fused Deposition Molding (FDM), and the substrate 101 is provided with a detection cell bottom slot 201, a liquid inlet bottom slot 301, a liquid outlet bottom slot 601, a wheatstone bridge resistor R₁Bottom groove 1101, HuisTON bridge resistance R₂Bottom slot 1201 and Wheatstone bridge resistor R₃ A bottom groove 1301;

b) as shown in fig. 6, a 3D print head 16 is used to prepare a detection cell sacrificial layer substrate 202 in a detection cell bottom groove 201 by using a water-soluble polymer material supporting fuse manufacturing (Fused Deposition Molding, FDM), the height of the detection cell sacrificial layer substrate 202 is the same as the depth of the detection cell bottom groove 201, a micro-cantilever detection sensor bottom groove 403 for placing a micro-cantilever detection sensor 4 and a micro-cantilever reference sensor bottom groove 501 for placing a micro-cantilever reference sensor 5 are provided on the detection cell sacrificial layer substrate 202, and a liquid inlet sacrificial layer 302 and a liquid outlet sacrificial layer 602 are also prepared on the liquid inlet bottom groove 301 and the liquid outlet bottom groove 601 by using a water-soluble polymer material;

c) as shown in fig. 7, a 3D print head 16 is used to fabricate a substrate biochemical passivation layer 402 of the micro-cantilever detection sensor 4 at the upper end of the micro-cantilever detection sensor bottom trench 403 and a micro-cantilever reference sensor substrate 502 of the micro-cantilever reference sensor 5 at the upper end of the micro-cantilever reference sensor bottom trench 501, using a flexible polymer material doped with a specific insensitive component that supports fuse Fabrication (Fused Deposition Fabrication) or Fused Deposition Molding (FDM) technology; the substrate biochemical passivation layer 402 and the micro-cantilever beam reference sensor substrate 502 are both provided with a variable piezoresistive sensitive layer R for placing an electric bridge _X14 piezoresistive sensitive layer floor trench 1401;

d) as shown in fig. 8, a 3D print head 16 is used to fabricate the variable piezoresistive sensitive layer R of the bridge of the micro-cantilever detection sensor 4 and the micro-cantilever reference sensor 5 in a piezoresistive sensitive layer bottom trench 1401 using a flexible polymer material doped with piezoresistive sensitive components supporting fuse Fabrication (Fused Deposition Fabrication) or Fused Deposition Molding (FDM) technology _X 14；

e) As shown in fig. 9, the 3D print head 16 is used to electrically bridge a wheatstone bridge using a rigid polymer material doped with a resistive component that supports either fuse Fabrication (fuse Fabrication) or Fused Deposition Molding (FDM) techniquesResistance R₁Bottom slot 1101, Wheatstone bridge resistor R₂Bottom slot 1201 and Wheatstone bridge resistor R₃A Wheatstone bridge resistor R is prepared in the bottom groove 1301₁11. Wheatstone bridge resistor R ₂12 and a Wheatstone bridge resistor R ₃13；

f) As shown in fig. 10, a bridge driving positive lead 7, a bridge driving negative lead 8, a voltage output positive lead 9, and a voltage output negative lead 10 are prepared on a substrate 101 using a 3D print head 16 using curable conductive ink supporting a fuse Fabrication (Fused deposition Fabrication) or Fused Deposition Modeling (FDM) technique;

g) as shown in fig. 11, the 3D print head 16 is used to fabricate a micro-cantilever reference sensor dome 503 of the micro-cantilever reference sensor 5 using a flexible polymer material doped with a specific insensitive component that supports fuse Fabrication (Fused deposition Fabrication) or Fused Deposition Modeling (FDM) techniques;

h) as shown in fig. 12, the 3D print head 16 is used to fabricate a capped bio-sensitive layer 401 of the micro-cantilever detection sensor 4 using a flexible polymer material doped with a specific sensitive component 19 supporting fuse Fabrication (Fused deposition Fabrication) or Fused Deposition Modeling (FDM) techniques;

i) as shown in fig. 13, a detection cell sacrificial layer capping 203 is prepared using a 3D print head 16 using a water-soluble polymer material supporting fuse Fabrication (Fused Deposition Fabrication) or Fused Deposition Molding (FDM) techniques, the detection cell sacrificial layer capping 203 fully covers the upper end surfaces of a detection cell sacrificial layer substrate 202, a liquid inlet sacrificial layer 302, a liquid outlet sacrificial layer 602, a micro-cantilever reference sensor capping 503, and a capping biochemical sensitive layer 401, and the detection cell sacrificial layer capping 203 encases the micro-cantilever reference sensor capping 503 and the capping biochemical sensitive layer 401 around three sides;

j) as shown in fig. 14, the 3D print head 16 is used to prepare the capping 102 of the integrated micro-cantilever detection chip 1 using a rigid polymer material supporting fuse Fabrication (Fused fiber Fabrication) or Fused Deposition Modeling (FDM) technology,the capping 102 caps the substrate 101, the sacrificial layer 203 of the detection cell, the positive lead 7 of the bridge drive, the negative lead 8 of the bridge drive, the positive lead 9 of the voltage output, the negative lead 10 of the voltage output, and the Wheatstone bridge resistor R ₁11. Wheatstone bridge resistor R ₂12 and a Wheatstone bridge resistor R₃The upper end of the cover 13 is fully covered, and the two sides of the substrate 101 and the cover 102 are respectively combined into a liquid inlet 3 and a liquid outlet 6;

k) in a heatable ultrasonic cleaning machine, the detection cell sacrificial layer substrate 202, the detection cell sacrificial layer capping 203, the liquid inlet sacrificial layer 302 and the liquid outlet sacrificial layer 602 are removed while heating and vibration cleaning, and then the micro-cantilever detection sensor 4 and the micro-cantilever reference sensor 5 are released, so that the integrated micro-cantilever detection chip 1 shown in fig. 1, 2 and 3 can be obtained.

The terms "flexible" and "rigid", "sensitive" and "insensitive" as used herein are relative concepts.

The principle of the invention is as follows:

the detection principle of the micro-cantilever sensor is as follows: when the detection is carried out, one end of the micro-cantilever beam detection sensor is fixed (called as the fixed end of the micro-cantilever beam), when the stress or the mass of the other end (called as the free end of the micro-cantilever beam) is changed, the posture or the vibration characteristic of the cantilever beam is changed, the changes are detected and converted into electric signals to be output, and the stress or mass change condition of the free end of the micro-cantilever beam sensor can be deduced according to the change of the output electric signals. According to the detection principle, the micro-cantilever sensor can be divided into a static working mode and a dynamic working mode. Since the dynamic working mode needs to apply external excitation on the micro-cantilever sensor, so that the micro-cantilever vibrates and then detects the change condition of the amplitude, frequency or phase, and no matter non-contact excitation modes such as a magnetic field, an electric field, an acoustic wave and the like, or contact excitation modes such as a piezoelectric field, a thermal field and the like need to add an additional functional module on a chip, the difficulty of design and integrated preparation is further increased, and therefore, a static working mode without external excitation is selected as the working mode of the integrated micro-cantilever sensor.

In the static operation mode, when the micro-cantilever posture changes, the deflection amount of the micro-cantilever sensor can be expressed as formula (1) under the condition that the elastic coefficient of the micro-cantilever sensor is known. Wherein q is the deflection of the cantilever beam during detection, F_tsThe external force or the mass change condition of the free end of the micro cantilever beam, and k is the elastic coefficient of the cantilever beam.

From the equation (1), it can be seen that in order to clarify the stress or mass change condition of the free end of the micro-cantilever sensor, the deflection (q) must be accurately obtained. The methods which can be used for detecting the deflection (q) of the micro-cantilever sensor at present comprise three main types, namely a tunneling microscope method, an optical method and an electrical detection method. When the deflection of the cantilever beam is extracted by adopting a tunnel microscope method, an additional scanning tunnel microscope is needed, the structure is very complex, and the method is not suitable for the integrated application of the sensor; the optical method usually requires precise and complicated optical path design, and cannot realize miniaturization. The electrical method comprises 3 piezoelectric, capacitance and piezoresistive methods, wherein the piezoresistive method does not need a complex structure of the capacitance method, does not relate to a complicated decoupling method in the piezoelectric method, and is very suitable for integrated and portable application of the micro-cantilever sensor. Therefore, the piezoresistive method is selected as the method for extracting the deflection (q) of the micro-cantilever sensor in the static working mode.

Piezoresistive methods are based on the piezoresistive effect of the device. Piezoresistive effect is a principle discovered by Lord Kelvin in 1856 and widely applied to a sensor sensitive element. This effect provides a simple and direct energy-to-signal conversion mechanism between mechanical and electrical energy. Pressure sensitive devices have been used in many MEMS applications such as accelerometers, pressure sensors, biosensors, and the like. The basic principle of piezoresistive effect can be expressed as formula (2). Wherein R is the resistance value, L is the material length, rho is the material resistivity, and A is the material cross-sectional area. When the pressure resistance is subjected to a force F_tsWhen acting, the elongation dL is reduced, the cross-sectional area is correspondingly reduced by dA, and the resistivity is deformed due to the crystal lattice of the materialThe influence changes dp, resulting in a change dR in the resistance value.

As can be seen from the equation (2), the resistance change of the piezoresistor (i.e. the piezoresistive sensitive layer 14 (R) in the present invention) can be determined_X) The deflection of the micro-cantilever sensor can be deduced, and the stress or mass change condition of the free end of the micro-cantilever sensor can be further obtained.

The invention adopts a Wheatstone bridge to connect the variable piezoresistive sensitive layer R of the bridge_XAnd (4) converting the resistance change condition of the micro-cantilever into an electric signal to be output, and judging the stress or mass change of the free end of the micro-cantilever according to the change of the electric signal. The operating principle of the wheatstone bridge is as shown in fig. 4, and is a bridge circuit composed of four resistors. Wherein, a Wheatstone bridge resistor R ₁11. Wheatstone bridge resistor R ₂12 and a Wheatstone bridge resistor R ₃13 is a fixed resistance resistor, and the fourth resistor: variable piezoresistive sensitive layer R of bridge_XAnd 14 is a variable resistor. The initial state (variable piezoresistive sensitive layer R of the bridge) can be realized by controlling the process parameters _X14 is not deformed), the resistance values of the four arms of the bridge are equal, namely the resistance R of the Wheatstone bridge ₁11. Wheatstone bridge resistor R ₂12. Wheatstone bridge resistor R ₃13 variable piezoresistive sensitive layer R of bridge _X14 are equal in resistance. Subsequently, a voltage is applied between points a and C in the circuit through the bridge-driving positive electrode wire 7 and the bridge-driving negative electrode wire 8; the detection circuit is connected between points B and C of the circuit by a voltage output positive lead 9 and a voltage output negative lead 10. Because the resistances of the four arms of the bridge are equal, no potential difference is generated between the point B and the point C in the initial state, and no current flows. If the free end of the micro-cantilever beam deforms due to external force or mass change, the variable piezoresistive sensitive layer R of the bridge embedded therein will inevitably be caused_X14, and thus the resistance value thereof. At this time, the balance of the bridge is broken and the bridge is connected between the points B and CThe detection instrument will generate an indication. The variable piezoresistive sensitive layer R of the bridge can be obtained by the index _X14, and further determining the stress or mass change condition of the free end of the micro-cantilever.

The detection principle of the piezoresistive micro-cantilever sensor operating in the static mode is briefly described above, but when the sensor is used in combination with a microfluidic chip, particularly when a liquid sample containing multiple components is detected, the micro-cantilever detection sensor 4 used alone is easily interfered by other components in the sample, so that the detection result is deviated. Therefore, the micro-cantilever reference sensor 5 is added to form a first sensor detection unit 17 and a second sensor detection unit 18 together with the micro-cantilever detection sensor 4, so as to eliminate the interference of irrelevant components in the sample on the detection result. The working principle of the first sensor detection unit 17 and the second sensor detection unit 18 consisting of the micro-cantilever detection sensor 4 and the micro-cantilever reference sensor 5 is shown in fig. 15:

in an initial state, namely when no sample to be detected is injected into the detection cell 2 provided with the micro-cantilever, no matter the micro-cantilever detection sensor 4 or the micro-cantilever reference sensor 5 deflects; in the operating state, that is, when a sample containing a plurality of components is injected into the detection cell 2 in which the micro-cantilever is installed, the micro-cantilever detection sensor 4 and the micro-cantilever reference sensor 5 both deflect, but the deflection amplitudes are different. The deflection amplitude of the micro-cantilever detection sensor 4 is larger and the deflection amplitude of the micro-cantilever reference sensor 5 is smaller. This is because after the sample containing a plurality of components is injected into the detection cell 2 equipped with the micro-cantilever, the micro-cantilever detection sensor 4 can be specifically combined with the sample 20 to be detected by virtue of the specific sensitive component 19 doped in the capping biochemical sensitive layer 401. The substrate biochemical passivation layer 402 of the micro-cantilever detection sensor 4 will not bind to the sample 20 to be detected due to the doping of the specific insensitive component. The upper and lower surfaces of the micro-cantilever detection sensor 4 made of different materials will generate stress differences due to different binding capacities to the sample 20 to be detected, thereby causing the micro-cantilever detection sensor 4 to deflect. At the same time, the interfering ions 21 in the sample are also attached to the upper and lower surfaces of the micro-cantilever detection sensor 4 by the adsorption action of the solid surface. This adsorption is non-specific and occurs either on the capping bio-sensitive layer 401 or the base bio-passivation layer 402. The suction will increase the mass of the free end and will also cause deflection of the micro-cantilever detection sensor 4. Cantilever sensors with characteristic dimensions in the micron range typically deflect in the sub-micron to nanometer range, so deflection due to adsorption is an irrespectively disturbing signal.

In order to compensate the increase of deflection of the micro-cantilever beam detection sensor 4 caused by the adsorption effect of the solid surface, a variable piezoresistive sensitive layer R of the bridge, the physical dimension, the material performance of the main structure and the electrical bridge are introduced_X14 material and dimensions thereof are consistent with those of the micro-cantilever reference sensor 5. The upper surface and the lower surface of the micro-cantilever reference sensor 5 are both made of the same flexible polymer material doped with the specific insensitive component as the substrate biochemical passivation layer 402, cannot be specifically combined with the sample 20 to be detected, and only can be combined with the interfering ions 21 in the sample by virtue of the adsorption effect. After binding with the interfering ions 21, the micro-cantilever reference sensor 5 will also deflect due to the change in mass at the free end. The detection signal generated by the specific adsorption of the sample 20 to be detected by the capped biochemical sensitive layer 401 can be obtained by subtracting the larger signal change between the two points of the bridge circuit B, C caused by the deflection of the micro-cantilever beam detection sensor 4 and the smaller signal change between the two points of the bridge circuit B, C caused by the deflection of the micro-cantilever beam reference sensor 5.

When the sample contains two or more components to be detected, a detection unit comprising a micro-cantilever detection sensor 4 and a micro-cantilever reference sensor 5, namely a first sensor detection unit 17, a second sensor detection unit 18 and a corresponding bridge circuit can be added in the detection cell 2 provided with the micro-cantilever. Each detection unit needs to be designed in a customized way according to a sample to be detected (comprising a specific sensitive component 19, a capping biochemical sensitive layer 401, a substrate biochemical passivation layer 402, the overall dimension of the micro-beam sensor, the performance of a main structure material and the variable piezoresistive sensitive of the bridgeLayer R _X14 materials and their dimensional parameters, etc.) to ensure specific identification of the sample to be tested.

Example (b):

in this embodiment, an Ultimaker S53D printer is selected to prepare an integrated micro-cantilever detection chip. The Ultimaker S53D printer adopts fuse manufacturing (Fused fiber Fabrication) printing technology, is provided with double printing heads, can rapidly change each printing head, and can realize the manufacture of devices with different precisions and different materials by changing the printing heads. The printer prints with a device size not smaller than: length × width × height is 300 × 200 × 300 mm; the limit printing precision is not lower than: x × Y × Z is 10 × 10 × 5 μm; continuously adjustable within the range of 20-600 mu m after printing the layer. In addition, the printer supports various materials such as PLA, Nylon, TPU, ABS, CPE, PP, PVA (water-soluble printing material) and the like, and the printing process can be monitored in real time. According to the process flow of fig. 5-14, the method of the present invention comprises the following steps:

1. and (4) preparing materials.

a) Polypropylene (PP) is selected as the main material of the substrate 101 and the cap 102 of the integrated detection chip 1. The PP material is a polymer formed by propylene addition polymerization, and is transparent and light in appearance. The PP material can resist the corrosion of acid, alkali, salt solution and various organic solvents at the temperature of below 80 ℃, has good grafting and compounding functions, and is an ideal biochemical compatible material.

b) Thermoplastic polyurethane elastomer (TPU) material was chosen as the host material for the micro-cantilever sensor. The TPU is a high molecular material formed by jointly reacting and polymerizing diisocyanate molecules such as diphenylmethane diisocyanate (MDI) or Toluene Diisocyanate (TDI), etc., and macromolecular polyol and low-molecular polyol (chain extender). The main advantages of TPUs include: excellent adhesion, low viscosity, good flex resistance, excellent wear resistance, high gloss, weatherability, resistance to any sun exposure including UV irradiation, excellent toughness and durability in various application areas.

c) Water-soluble polyvinyl alcohol (PVA) is selected as the detection cell sacrificial layer substrate 202, the detection cell sacrificial layer capping 203, the liquid inlet sacrificial layer 302 and the liquid outlet sacrificial layer 602. The water-soluble PVA has a water-soluble temperature of 10-90 ℃, the higher the water temperature, the higher the solubility, and the water-soluble PVA is almost insoluble in an organic solvent, so that the water-soluble PVA is very suitable for being used as a sacrificial layer material.

d) Thiolated siloxane fluorohydrin (TSXFA) is chosen as the specific sensitive component 19 in the capped biochemical sensitive layer 401 of the micro-cantilever detection sensor 4 in the first sensor detection unit 17. The TSXFA can specifically absorb alcohol in the solution, so that the micro-cantilever detection sensor 4 is deformed due to the change of mass. Under the melting state, TSXFA and TPU materials are uniformly mixed according to a proportion, and then are drawn and dried for standby.

e) Methyl phenyl mercapto propyl siloxane (OV 17 MCP20) was chosen as the specific sensing component 19 in the capped biochemical sensitive layer 401 of the microcantilever detection sensor 4 in the second sensor detection unit 18. The OV17 MCP20 can specifically adsorb organic phosphorus components in the solution, so that the micro-cantilever detection sensor 4 deforms due to mass change. In a molten state, OV17 MCP20 and TPU materials are uniformly mixed according to a proportion, and then are drawn and dried for later use.

f) Since TPU is not sensitive to alcohol and organic phosphorus components in the solution, in this embodiment, the substrate biochemical passivation layer 402, the micro-cantilever reference sensor substrate 502, and the micro-cantilever reference sensor capping 503, which use TPU materials as main bodies, do not need to add additional specific insensitive components.

g) A bridge driving positive wire 7, a bridge driving negative wire 8, a voltage output positive wire 9, a voltage output negative wire 10 and a bridge resistor interconnection wire 15 are prepared by conductive ink containing nano silver ions. The conductive ink is a suspension state of metal nanoparticles in a host solvent. After the printing of the conducting wire is finished, standing for a period of time until the nanometer suspension is deposited, irradiating the conducting wire by using an ultraviolet lamp to volatilize the solvent in the suspension, and curing and forming the conducting wire.

h) 1-ethyl-3-methylimidazolium tetrafluoroborate (1-ethyl-3-methylimidazolium tetrafluoroborate, EMBBF 4) and Tangoplus novel classThe rubber elastic material is uniformly mixed, drawn and dried according to a certain mass ratio to be used for preparing a piezoresistive sensitive layer (a variable piezoresistive sensitive layer R of a bridge)_X14) The material of (a) is ready for use.

i) Mixing acrylonitrile-butadiene-styrene copolymer (ABS) and Carbon Black (CB) powder according to a certain mass ratio, drawing, drying to obtain Wheatstone bridge resistor R ₁11. Wheatstone bridge resistor R ₂12. Wheatstone bridge resistor R ₃13 is ready for use.

2. And (6) slicing the device. And cutting the three-dimensional model of the device into a series of cross-section sheets along the selected model forming direction through slicing software matched with a printer, and guiding the sliced device into a memory of the printer.

3. And (5) testing the printer. The Ultimaker S53D printer needs to test the power supply function, knob function, print head movement and whether it is jammed before printing.

4. As shown in FIG. 5, the substrate 101 of the integrated micro-cantilever detection chip 1 was prepared by filling PP material using an Ultimaker S53D printer. The substrate 101 is provided with a detection cell bottom groove 201, a liquid inlet bottom groove 301, a liquid outlet bottom groove 601, and a Wheatstone bridge resistor R₁Bottom slot 1101, Wheatstone bridge resistor R₂Bottom slot 1201 and Wheatstone bridge resistor R₃ A bottom groove 1301.

5. As shown in fig. 6, an Ultimaker S53D printer is used to fill PVA material to prepare a sacrificial layer substrate 202 of the detection cell, the height of the sacrificial layer substrate 202 of the detection cell is the same as the depth of the bottom groove 201 of the detection cell, and the sacrificial layer substrate 202 of the detection cell is designed with a bottom groove 403 for placing the micro-cantilever detection sensor 4 and a bottom groove 501 for placing the micro-cantilever reference sensor 5. In addition, on inlet bottom tank 301 and outlet bottom tank 601, a water-soluble polymer material is also used to prepare inlet sacrificial layer 302 and outlet sacrificial layer 602.

6. As shown in FIG. 7, the basal biochemical passivation layer 402 of the micro-cantilever detection sensor 4 and the micro-cantilever of the micro-cantilever reference sensor 5 are prepared by filling TPU material with an Ultimaker S53D printerThe beam reference sensor substrate 502. The substrate biochemical passivation layer 402 and the micro-cantilever beam reference sensor substrate 502 are both provided with a variable piezoresistive sensitive layer R for placing an electric bridge _X14 piezoresistive sensitive layer floor trench 1401.

7. As shown in FIG. 8, a mixture of 1-ethyl-3-methylimidazolium tetrafluoroborate (1-ethyl-3-methylimidazolium tetrafluoroborate, EMBBF 4) and Tangoplus novel rubber-like elastic material is filled in an Ultimaker S53D printer to prepare the variable piezoresistive sensitive layers R of the piezoresistive sensitive layer bridges of the micro-cantilever detection sensor 4 and the micro-cantilever reference sensor 5 in a piezoresistive sensitive layer bottom groove 1401_X14。

8. As shown in FIG. 9, an Ultimaker S53D printer was used to load a powder mixture of acrylonitrile-butadiene-styrene (ABS) and Carbon Black (CB) at a Wheatstone bridge resistance R₁Bottom slot 1101, Wheatstone bridge resistor R₂Bottom slot 1201 and Wheatstone bridge resistor R₃A Wheatstone bridge resistor R is prepared in the bottom groove 1301₁11. Wheatstone bridge resistor R ₂12 and a Wheatstone bridge resistor R ₃13。

9. As shown in fig. 10, a bridge driving positive electrode lead 7, a bridge driving negative electrode lead 8, a voltage output positive electrode lead 9 and a voltage output negative electrode lead 10 were prepared on a substrate 101 of a chip by filling conductive ink containing nano silver ions using an Ultimaker S53D printer. After the printing of the conducting wire is finished, standing for a period of time until the nanometer suspension is deposited, and irradiating the conducting wire by using an ultraviolet lamp to volatilize the solvent in the suspension.

10. The microcantilever reference sensor seal cap 503 of the microcantilever reference sensor 5 was prepared as shown in figure 11 by reloading the TPU material using an Ultimaker S53D printer.

11. As shown in FIG. 12, a mixed material of TSXFA and TPU is filled in an Ultimaker S53D printer to prepare a capping biochemical sensitive layer 401 of the micro-cantilever detection sensor 4 in the detection unit 17, so that the detection sensor has the ability of specifically absorbing alcohol in solution.

12. As shown in FIG. 12, a mixed material of OV17 MCP20 and TPU is filled in an Ultimaker S53D printer to prepare a capped biochemical sensitive layer 401 of the micro-cantilever detection sensor 4 in the detection unit 18, so that the detection sensor has the capability of specifically absorbing organic phosphorus components in solution.

13. As shown in fig. 13, the detection cell sacrificial layer capping 203 was prepared by reloading PVA material using an Ultimaker S53D printer.

14. As shown in FIG. 14, the capping portion 102 of the integrated micro-cantilever detection chip 1 was prepared by reloading PP material using an Ultimaker S53D printer.

15. In a heatable ultrasonic cleaning machine, heating and vibrating cleaning are carried out simultaneously, the detection cell sacrificial layer substrate 202, the detection cell sacrificial layer capping 203, the liquid inlet bottom groove 301 and the liquid outlet bottom groove 601 in the chip are removed, and the micro-cantilever detection sensor 4 and the micro-cantilever reference sensor 5 are released, so that the integrated micro-cantilever detection chip shown in the figures 1-3 can be obtained. The chip has the capability of simultaneously detecting alcohol and organic phosphorus components in a solution.

Claims

1. The utility model provides a little cantilever beam of integration detects chip which characterized in that: the device comprises a substrate (101), wherein a detection pool bottom groove (201) is inwards formed in the upper end of the substrate (101), a liquid inlet bottom groove (301) and a liquid outlet bottom groove (601) are respectively formed in two sides, located on the detection pool bottom groove (201), of the upper end of the substrate (101), and a Wheatstone bridge resistor R is also inwards formed in one side, located on the detection pool bottom groove (201), of the upper end of the substrate (101)₁Bottom slot (1101) and Wheatstone bridge resistor R₂A bottom slot (1201) and a Wheatstone bridge resistor R₃The structure comprises a bottom groove (1301), wherein a substrate biochemical passivation layer (402) is arranged on the upper side inside the detection tank bottom groove (201), a micro-cantilever beam reference sensor substrate (502) is further arranged on the upper side inside the detection tank bottom groove (201), piezoresistive sensitive layer bottom grooves (1401) are formed in the upper ends of the substrate biochemical passivation layer (402) and the micro-cantilever beam reference sensor substrate (502), and a variable piezoresistive sensitive layer R of an electric bridge is prepared in each piezoresistive sensitive layer bottom groove (1401)_X(14) Wheatstone bridge resistance R₁A Wheatstone bridge resistor R is arranged in the bottom groove (1101)₁(11) Wheatstone bridge resistance R₂A Wheatstone bridge resistor R is arranged in the bottom groove (1201)₂(12) Wheatstone bridgeResistance R₃A Wheatstone bridge resistor R is arranged in the bottom groove (1301)₃(13) The upper end of the substrate (101) is provided with a bridge driving positive wire (7), a bridge driving negative wire (8), a voltage output positive wire (9) and a voltage output negative wire (10), and a Wheatstone bridge resistor R₁(11) Wheatstone bridge resistor R₂(12) Wheatstone bridge resistor R₃(13) Variable piezoresistive sensitive layer R of bridge_X(14) A Wheatstone bridge-based detection signal extraction circuit consisting of a bridge driving positive wire (7), a bridge driving negative wire (8), a voltage output positive wire (9) and a voltage output negative wire (10), and a Wheatstone bridge resistor R₁(11) And a Wheatstone bridge resistor R₂(12) Is commonly connected to one end of a bridge driving positive lead (7), and the other end of the bridge driving positive lead (7) is used for being connected to a driving voltage V_GPositive electrode of (2), Wheatstone bridge resistor R₃(13) Variable piezoresistive sensitive layer R of bridge_X(14) Is commonly connected with one end of a bridge driving negative electrode lead (8), and the other end of the bridge driving negative electrode lead (8) is used for being connected with a driving voltage V_GNegative pole of (1), Wheatstone bridge resistor R₁(11) And a Wheatstone bridge resistor R₃(13) The other end of the first and second resistors are connected to one end of a voltage output negative lead (10) and a Wheatstone bridge resistor R₂(12) Variable piezoresistive sensitive layer R of bridge_X(14) The other end of the voltage output negative electrode lead (10) and the other end of the voltage output positive electrode lead (9) are used for being connected to corresponding detection equipment, a micro-cantilever beam reference sensor capping (503) is prepared at the upper end of a micro-cantilever beam reference sensor substrate (502), and the upper end surface of the micro-cantilever beam reference sensor substrate (502) and a variable piezoresistance sensitive layer R of an electric bridge are capped by the micro-cantilever beam reference sensor capping (503)_X(14) Full coverage, micro-cantilever reference sensor substrate (502), micro-cantilever reference sensor capping (503) and variable piezoresistive sensitive layer R of bridge_X(14) The micro-cantilever beam reference sensor (5) is formed, a capping biochemical sensitive layer (401) is prepared at the upper end of a substrate biochemical passivation layer (402), and the capping biochemical sensitive layer (401) enables the upper end face of the substrate biochemical passivation layer (402) and the bridge to be connectedVariable piezoresistive sensitive layer R_X(14) Fully covering and capping the biochemical sensitive layer (401), the substrate biochemical passivation layer (402) and the variable piezoresistive sensitive layer R of the bridge_X(14) The micro-cantilever detection sensor (4) is formed, a capping (102) is prepared at the upper end of a substrate (101), and the capping (102) enables the substrate (101), a bridge driving positive lead (7), a bridge driving negative lead (8), a voltage output positive lead (9), a voltage output negative lead (10) and a Wheatstone bridge resistor R to be connected with the substrate (101), the bridge driving positive lead (7), the bridge driving negative lead (8), the voltage output positive lead (9), the voltage output negative lead (10)₁(11) Wheatstone bridge resistor R₂(12) And a Wheatstone bridge resistor R₃(13) The upper end of the liquid inlet is fully covered, the micro-cantilever beam reference sensor (5) and the micro-cantilever beam detection sensor (4) are positioned in a detection pool formed by a detection pool bottom groove (201) of the top cover (102) and the substrate (101), and two sides of the substrate (101) and the top cover (102) are respectively combined into a liquid inlet (3) and a liquid outlet (6).

2. The integrated micro-cantilever detection chip of claim 1, wherein: the base (101) and the cap (102) are both rigid polymeric materials.

3. The integrated micro-cantilever detection chip of claim 1, wherein: the substrate biochemical passivation layer (402) and the micro-cantilever beam reference sensor capping layer (503) are both made of flexible polymer materials doped with specific insensitive components, and the capping biochemical sensitive layer (401) is made of flexible polymer materials doped with specific biochemical sensitive components.

4. The integrated micro-cantilever detection chip of claim 1, wherein: the variable piezoresistive sensitive layer R of the bridge_X(14) Is a flexible polymeric material doped with a piezoresistive sensitive component.

5. The integrated micro-cantilever detection chip of claim 1, wherein: the Wheatstone bridge resistor R₁(11) Wheatstone bridge resistor R₂(12) And a Wheatstone bridge resistor R₃(13) Are both rigid polymeric materials doped with a resistive component.

6. The integrated micro-cantilever detection chip of claim 1, wherein: the bridge driving positive lead (7), the bridge driving negative lead (8), the voltage output positive lead (9) and the voltage output negative lead (10) are all curable conductive ink.

7. The integrated micro-cantilever detection chip of claim 1, wherein: the bottom groove (1401) of the piezoresistive sensitive layer and the variable piezoresistive sensitive layer R of the bridge_X(14) Is W-shaped.

8. The integrated micro-cantilever detection chip of claim 1, wherein: the micro-cantilever beam detection sensor (4) and the adjacent micro-cantilever beam reference sensor (5) form a group of sensor detection units, and the overall dimensions, the main structure material performance, the piezoresistive sensitive layer material and the characteristic dimensions of the micro-cantilever beam detection sensor (4) and the adjacent micro-cantilever beam reference sensor (5) in each group of sensor detection units are all ensured to be consistent.

9. The preparation method of the integrated micro-cantilever detection chip of claim 1, wherein: the method comprises the following steps:

a) the rigid polymer material uses a 3D printing head (16) to prepare a substrate (101) of an integrated micro-cantilever detection chip (1), and the substrate (101) is provided with a detection pool bottom groove (201), a liquid inlet bottom groove (301), a liquid outlet bottom groove (601), a Wheatstone bridge resistor R₁Bottom slot (1101) and Wheatstone bridge resistor R₂A bottom slot (1201) and a Wheatstone bridge resistor R₃A bottom groove (1301);

b) a water-soluble polymer material uses a 3D printing head (16) to prepare a detection pool sacrificial layer substrate (202) in a detection pool bottom groove (201), the height of the detection pool sacrificial layer substrate (202) is consistent with the depth of the detection pool bottom groove (201), a micro-cantilever beam detection sensor bottom groove (403) for placing a micro-cantilever beam detection sensor (4) and a micro-cantilever beam reference sensor bottom groove (501) for placing a micro-cantilever beam reference sensor (5) are arranged on the detection pool sacrificial layer substrate (202), and a liquid inlet sacrificial layer (302) and a liquid outlet sacrificial layer (602) are also prepared by using the water-soluble polymer material on a liquid inlet bottom groove (301) and a liquid outlet bottom groove (601);

c) preparing a substrate biochemical passivation layer (402) of a micro-cantilever detection sensor (4) at the upper end of a micro-cantilever detection sensor bottom groove (403) by using a 3D printing head (16) and preparing a micro-cantilever reference sensor substrate (502) of a micro-cantilever reference sensor (5) at the upper end of a micro-cantilever reference sensor bottom groove (501) by using a flexible polymer material doped with specific insensitive components; the substrate biochemical passivation layer (402) and the micro-cantilever reference sensor substrate (502) are both provided with a variable piezoresistive sensitive layer R for placing an electric bridge_X(14) A piezoresistive sensitive layer bottom groove (1401);

d) flexible polymer material doped with piezoresistive sensitive component A3D printing head (16) is used to prepare a variable piezoresistive sensitive layer R of an electrical bridge of a micro-cantilever detection sensor (4) and a micro-cantilever reference sensor (5) in a piezoresistive sensitive layer bottom groove (1401)_X(14)；

e) Rigid polymer material doped with resistive component using 3D printhead (16) at Wheatstone bridge resistance R₁Bottom slot (1101) and Wheatstone bridge resistor R₂A bottom slot (1201) and a Wheatstone bridge resistor R₃Preparation of Wheatstone bridge resistor R in bottom groove (1301)₁(11) Wheatstone bridge resistor R₂(12) And a Wheatstone bridge resistor R₃(13)；

f) Curable conductive ink using a 3D printhead (16) to prepare a bridge-driven positive lead (7), a bridge-driven negative lead (8), a voltage output positive lead (9), and a voltage output negative lead (10) on a substrate (101);

g) preparing a microcantilever reference sensor capping (503) of a microcantilever reference sensor (5) from a flexible polymer material doped with a specific insensitive component using a 3D print head (16);

h) preparing a capping biochemical sensitive layer (401) of a micro-cantilever detection sensor (4) from a flexible polymer material doped with a specific sensitive component (19) using a 3D printing head (16);

i) the water-soluble polymer material uses a 3D printing head (16) to prepare a detection pool sacrificial layer capping (203), the detection pool sacrificial layer capping (203) fully covers the upper end faces of a detection pool sacrificial layer substrate (202), a liquid inlet sacrificial layer (302), a liquid outlet sacrificial layer (602), a micro-cantilever beam reference sensor capping (503) and a capping biochemical sensitive layer (401), and the detection pool sacrificial layer capping (203) covers three circles of the micro-cantilever beam reference sensor capping (503) and the capping biochemical sensitive layer (401);

j) a rigid polymer material is used for preparing a capping (102) of an integrated micro-cantilever detection chip (1) by using a 3D printing head (16), and the capping (102) is used for capping a substrate (101), a detection cell sacrificial layer (203), a bridge driving positive lead (7), a bridge driving negative lead (8), a voltage output positive lead (9), a voltage output negative lead (10) and a Wheatstone bridge resistor R₁(11) Wheatstone bridge resistor R₂(12) And a Wheatstone bridge resistor R₃(13) The upper end of the cover is fully covered, and two sides of the substrate (101) and the cover top (102) are respectively combined into a liquid inlet (3) and a liquid outlet (6);

k) in a heatable ultrasonic cleaning machine, the ultrasonic cleaning machine is heated and vibrated at the same time, a detection pool sacrificial layer substrate (202), a detection pool sacrificial layer capping (203), a liquid inlet sacrificial layer (302) and a liquid outlet sacrificial layer (602) are removed, and then a micro-cantilever detection sensor (4) and a micro-cantilever reference sensor (5) are released to obtain the integrated micro-cantilever detection chip (1).