CN113671213B - MEMS electrochemical vibration sensor sensitive electrode based on silicon conduction and manufacturing method thereof - Google Patents

Abstract

The invention discloses a silicon-based conductive MEMS electrochemical vibration sensor sensitive electrode and a manufacturing method thereof. The electrode includes: a substrate; an insulating layer on the front and back of the substrate; the front insulating layer includes a first area and a second area that are insulated; the back insulating layer includes a third area and a fourth area that are insulated; the first area and the third area It includes an anode access surface, each anode access surface has an anode voltage access point and at least one anode access hole; the first cathode is formed on the second region; a plurality of flow channel holes are located in the second region; the anode connection The inlet hole and the flow channel hole run through the front and back insulating layers and the substrate; the second cathode is formed on the fourth area; the side wall anode of the flow channel hole is formed on the inner side wall of the flow channel hole, respectively connected to the first cathode and the second Cathode insulation set. Using the silicon conductive lead method, the anode on the side wall of each flow hole is drawn out without occupying the surface area of the silicon chip, which increases the cathode area on the surface of the silicon chip and improves the sensitivity of the device.

Description

A sensitive electrode of MEMS electrochemical vibration sensor based on silicon conduction and its manufacture method

technical field

The invention relates to the fields of MEMS sensors and low-frequency vibration measurement, in particular to the field of MEMS process manufacturing, in particular to a silicon-based conductive MEMS electrochemical vibration sensor sensitive electrode and a manufacturing method thereof.

Background technique

Vibration sensors based on various principles have been developed. According to different working principles, it can be divided into piezoelectric accelerometers, optical fiber sensors, electrochemical vibration sensors, etc. In addition to electrochemical vibration sensors, the vibration sensing units of the above vibration sensors use precision mechanical components as inertial masses. There are problems such as large size and heavy weight of the device, while the electrochemical vibration sensor uses liquid solution as the inertial mass, does not need position and center adjustment, has a larger working inclination, and has high sensitivity, large dynamic range and low self-noise.

The core unit of the electrochemical vibration sensor is composed of sensitive electrodes, electrolyte, etc. Sensitive electrodes mainly adopt the arrangement of anode-cathode-cathode-anode. The electrolyte is composed of aqueous solution containing KI and I ₂ , in which I ^- loses electrons at the anode to generate I ₃ ^- , while I ₃ ^- gains electrons at the cathode to generate I ^- . When the outside world vibrates, ions flow relative to the electrodes, resulting in an imbalance of ions between the two negative and positive electrodes, resulting in an imbalance in the output current. By detecting the unbalanced current, the vibration amplitude and frequency can be obtained. This is the electrochemical vibration sensor. working principle. Therefore, the manufacturing quality of the sensitive electrode of the electrochemical vibration sensor is related to the sensitivity and other important properties of the device.

At present, MEMS (Micro-Electro-Mechanical-System, micro-electromechanical system) sensitive electrode structures mainly include ACCA four-electrode structure and CAC three-electrode structure. Sensitivity of the sensor. Electrodes have changed from the early manual alignment of seven-layer porous plates to the use of wafer-level bonding to align two-layer chips, and finally achieve monolithic integration to improve electrode integration.

How to wire the electrodes is an important issue while reducing the number of chips. The platinum electrodes of each layer of the multi-layer chip cover different chip surfaces respectively, and the voltage can be easily connected from the lead wires on the surface of each chip. However, a pair of anodes and cathodes of ACCA structure sensitive electrodes integrated on a chip need to be fabricated on the same side, and the anode surrounds the cathode (or the cathode surrounds the anode), and complex metal lines need to be sputtered on the surface of the chip to be surrounded. The electrodes are connected to the peripheral voltage access point leads; the sensitive electrodes of the CAC structure integrated on a chip are arranged in the form of front cathode, middle anode, and back cathode, and the anodes are distributed on the side walls of each independent channel hole, which also needs to be Complex metal lines sputtered on the surface connect the anode of each flow hole to the surface of the chip and lead externally. This method of sputtering complex metal lines on the surface of the chip to connect the dispersed electrodes for wiring increases the complexity of the process and reduces the utilization rate of the chip surface area. Therefore, the present invention proposes a wiring method using the silicon support layer to conduct electricity. The electrodes do not need to be wired from the surface, which simplifies the process and increases the effective electrode area on the chip surface.

Contents of the invention

In order to solve the above-mentioned problems in the prior art, the object of the present invention is to propose a silicon-based conductive MEMS electrochemical vibration sensor sensitive electrode and its manufacturing method, to solve the problem of integrated sensitive electrode leads, reduce process steps, and increase the number of cathodes area, optimize electrode size parameters, and improve sensor sensitivity.

The present invention adopts following technical means:

A sensitive electrode of a MEMS electrochemical vibration sensor based on silicon conduction, including a substrate, a first insulating layer, a second insulating layer, a plurality of flow channel holes, a first cathode, anodes on the side walls of the flow channel holes, a second cathode, and an anode contact Access hole and anode voltage access.

The substrate has a first surface and a second surface opposite to each other;

a first insulating layer formed on the first surface;

a second insulating layer formed on the second surface;

The first insulating layer is divided into a first region and a second region which are insulated from each other; wherein the first region includes a plurality of anode access surfaces.

The second insulating layer is divided into a third area and a fourth area which are insulated from each other; the third area includes a plurality of anode access surfaces. The multiple anode access surfaces on the third region are insulated or not insulated from each other.

Each anode access face has an anode voltage access.

In the first area, each anode access surface has at least one anode access hole penetrating to the anode access surface of the third area, and the anode access hole penetrates the first insulating layer, the substrate and the first insulating layer. Two insulating layers.

a first cathode formed on the second region, an insulating ring distributed along the periphery of the flow channel hole between the first cathode and the flow channel hole;

A plurality of flow channel holes located in the second region, the flow channel holes penetrate the first insulating layer, the base and the second insulating layer, and the outlet of the second insulating layer is located at the first insulating layer Four areas.

The second cathode is formed on the fourth region, and there is an insulating ring distributed along the periphery of the flow channel hole between the second cathode and the flow channel hole.

The anode on the side wall of the flow channel hole is formed on the inner side wall of the flow channel hole, and is insulated from the first cathode and the second cathode respectively.

Preferably, the pattern of the anode access surface of the first region is consistent with that of the anode connection surface of the third region.

Further, the anode on the side wall of the flow channel hole is respectively insulated from the first cathode and the second cathode through an insulating ring distributed along the periphery of the flow channel hole.

Further, the mutual insulation arrangement is realized by insulating tapes. The insulating tape is a silicon oxide or silicon nitride insulating tape. For example, the first region and the second region of the first insulating layer are insulated from each other by an insulating tape. The third region and the fourth region of the second insulating layer are insulated from each other by an insulating tape. The first area includes a plurality of anode access surfaces spaced apart by insulating tapes, and the insulation band realizes surface insulation between the plurality of anode access surfaces, and the anode access surfaces are connected to the metal and the silicon substrate through anode access holes Together.

The third region comprises two anode access faces separated by an insulating strip which provides surface insulation between the plurality of anode access faces.

Further, metal is sputtered on the inner sidewall of the anode access hole; preferably, the metal is Pt.

Further, the insulating layer material is selected from silicon oxide or silicon nitride.

Further, the distribution of the flow channel holes is circular or square.

Further, the substrate is a silicon wafer; preferably, the silicon wafer is selected from N-type silicon or P-type silicon.

所述金属层也可以为Pt层以及夹在Pt层和阳极接入面之间的Ti或Cr层，优选地，所述Pt层厚度为

所述Ti或Cr层厚度为

Further, the anode voltage access point is located on the anode access surface. The anode access surface has a metal layer; the inner wall of the anode access hole has a metal layer. The metal on the inner wall of the anode access hole is connected to the metal on the surface of the anode voltage access. Preferably, the metal on the inner wall of the anode access hole is directly connected to the metal on the surface of the anode voltage access point. For example, the metal layer is a Pt layer, preferably, the thickness of the Pt layer is

The metal layer can also be a Pt layer and a Ti or Cr layer sandwiched between the Pt layer and the anode access surface, preferably, the thickness of the Pt layer is

The thickness of the Ti or Cr layer is

Further, the anode on the side wall of the flow channel hole and the first cathode are insulated by an insulating ring wrapped around the flow channel hole.

Further, the anode and the second cathode on the side wall of the flow channel hole are insulated by an insulating ring wrapped around the flow channel hole.

Further, the insulating ring material is selected from silicon oxide or silicon nitride.

A method for manufacturing a sensitive electrode as described in any one of the above, comprising the following steps:

Step (1): Select and clean the substrate;

Step (2): Forming a first insulating layer and a second insulating layer on the first surface and the second surface of the substrate respectively;

Step (3): Using photoresist, perform glue-spinning, pre-baking, exposure, and development on the first insulating layer to form a first region, a second region, and a plurality of layers on the first region separated by insulating tapes. Anode access surfaces insulated from each other;

Step (4): growing a first cathode metal layer on the second region of the first insulating layer, and simultaneously growing metal layers on multiple anode access surfaces of the first region;

Step (5): removing the photoresist and the metal on the glue to form a first cathode and an anode access surface with a metal layer;

Step (6): Using photoresist, perform glue removal, pre-baking, overlay, and development on the second surface of the substrate, the process parameters are the same as step (3), and form the third area and the fourth area separated by insulating tapes , and a plurality of mutually insulated anode access surfaces on the third region;

Step (7): growing a second cathode metal layer on the fourth region on the second insulating layer; simultaneously growing metal layers on multiple anode access surfaces of the third region;

Step (8): removing the photoresist and the metal on the glue to form a second cathode and an anode access surface with a metal layer;

Step (9): Using photoresist, perform glue removal on the first insulating layer, pre-baking, front overlay, and development;

Step (10): using the photoresist in step (9) as a mask, etching the first insulating layer, then etching the substrate, and finally etching the second insulating layer to form flow channel holes and anode access holes;

Step (11): Use a dry film on the first insulating layer for exposure and development to cover the position of the first cathode pattern and insulation settings; the anode access hole and the anode access point need to be completely exposed, so that the anode access hole during sputtering Adequate metal connection of the sidewall and the surface of the anode access;

优选地，所述Pt层厚度为

Step (12): sputtering metal from the first insulating layer using a sputtering process. Preferably, the Ti or Cr layer is sputtered first, and then the Pt layer is sputtered; preferably, the thickness of the Ti or Cr layer is

Preferably, the thickness of the Pt layer is

Step (13): remove the dry film and metal to form the anode on the side wall of the flow channel hole; at the same time, complete the metal connection from the anode access point to the substrate to form a path from the voltage access point to the anode where the electrolyte reacts.

Further, the insulating layer is fabricated using a thermal oxygen process or deposited using a PECVD method.

Further, the growth of the first cathode metal layer in step (4) and the growth of the second cathode metal layer in step (7) adopt electron beam evaporation process respectively.

Further, in step (8), the second cathode metal pattern is completely consistent with the first cathode metal pattern.

Further, the shape of the channel hole is square or circular.

The present invention also provides a MEMS electrochemical vibration sensor based on silicon conduction, comprising the sensitive electrode described in any one of the above or the sensitive electrode manufactured by the method described in any one of the above.

Beneficial effects of the present invention:

(1) The structure of cathode-anode-cathode is used, and the method of integrating all electrodes on a single silicon chip is adopted. When assembling the device later, there is no need to manually align multiple pairs of electrodes, which reduces the difficulty of assembly.

(2) The consistency error of the electrode structure is only produced by the MEMS process, which improves the consistency of the device.

(3) Using silicon-conductive lead wires, the anode on the side wall of each flow hole is drawn out without occupying the surface area of the silicon chip, increasing the cathode area on the surface of the silicon chip, and improving the sensitivity of the device.

(4) The use of silicon conductive leads does not require complex metal lines to be sputtered on the surface, which avoids the problem that some anode flow holes are not used due to the fact that the surface leads may not be drawn out during the process, and reduces the complexity of the process pattern The degree also reduces the process steps and improves the sheeting rate.

(5) The present invention illustrates the feasibility of using silicon to introduce the electrode voltage, and provides a method for the lead wire problem in the subsequent electrode structure design.

Description of drawings

Fig. 1 MEMS sensitive electrode structure based on silicon conduction;

Figure 2 is a process flow chart of the MEMS sensitive electrode structure based on silicon conduction.

In the figure, 101: anode access hole; 102: anode voltage access 1; 103: anode voltage access 2; 104: front cathode; 105: insulating layer; 106 sensitive unit flow channel hole; 107: flow channel side Wall anode; 108 low-resistance silicon; 109: back cathode; 110: flow channel.

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. But following embodiment only limits to explain the present invention, and protection scope of the present invention should comprise the whole content of claim, and by the narration of following embodiment, those skilled in the art can fully realize the whole content of claim of the present invention.

FIG. 1 is an overall schematic diagram and a cross-sectional view of a silicon-based conductive sensitive electrode proposed by the present invention. As shown in Figure 1, the present invention provides a MEMS sensitive electrode structure based on silicon conduction, including a substrate, a first insulating layer, a second insulating layer, a plurality of sensitive unit channel holes 106, a front cathode 104, and channel side walls Anode 107, back cathode 109, anode access hole 101, anode voltage access 1102, anode voltage access 2103. The substrate may be a silicon wafer. In one embodiment of the present invention, the substrate is low-resistance silicon 108 . The insulating layer 105 includes a first insulating layer and a second insulating layer. Preferably, the insulating layer material is selected from silicon oxide or silicon nitride.

The first insulating layer is formed on the front side of the base, and the second insulating layer is formed on the back side of the base. There are multiple sensitive unit channel holes 106, and the sensitive unit channel holes 106 penetrate the first insulating layer, the base, and the second insulating layer. The channel hole 106 of the sensitive unit is an anode hole.

The first insulating layer is divided into a first region and a second region which are insulated from each other. The first region and the second region of the first insulating layer are separated by an insulating band.

Wherein the first area includes two anode access surfaces separated by an insulating tape, wherein one anode access surface has an anode voltage access point 1102 and at least one anode access hole 101; the other anode access surface has an anode The voltage access point 2103 and at least one anode access hole 101 .

The second insulating layer is divided into a third region and a fourth region which are insulated from each other, and the third region and the fourth region are separated by an insulating band. The third region includes two anode access faces separated by an insulating strip, each anode access face having an anode voltage access. Preferably, the pattern of the anode access surface on the first region is consistent with the pattern of the anode access surface on the third region.

In the first region, the anode access hole 101 penetrates to the anode access surface of the third region. The anode access hole 101 runs through the first insulating layer, the base and the second insulating layer.

所述金属层也可以为Pt层以及夹在Pt层和阳极接入面之间的Ti或Cr层，优选地，所述Pt层厚度为

所述Ti或Cr层厚度为

Each anode access surface has a metal layer; the side wall of the anode access hole 101 has a metal layer. The metal on the side wall of the anode access hole 101 in the same anode access plane is connected to the metal on the surface of the anode voltage access point. For example, the metal layer on the anode access surface is the same as the metal layer on the sidewall of the anode access hole 101, the metal layer is a Pt layer, and the thickness of the Pt layer is preferably

The metal layer can also be a Pt layer and a Ti or Cr layer sandwiched between the Pt layer and the anode access surface, preferably, the thickness of the Pt layer is

The thickness of the Ti or Cr layer is

A front cathode 104 is arranged on the second area, and there is an insulating ring distributed along the periphery of the flow channel hole 106 between the front cathode 104 and the channel hole 106 of the sensitive unit.

The channel side wall anode 107 is formed on the inner side wall of the channel hole 106 of the sensitive unit, and is separated from the front cathode 104 and the back cathode 109 by an insulating ring. The insulating ring wraps around the flow hole 106 of the sensitive unit, and the radial width of the insulating ring is 20um.

The back cathode 109 is formed on the fourth region of the second insulating layer, and is separated from the anode 107 on the side wall of the flow channel through an insulating ring.

The channel hole 106 of the sensitive unit is a channel for the electrolyte solution. Preferably, the front cathode 104 and the rear cathode 109 have the same pattern.

The first insulating layer, the second insulating layer, the insulating tape and the insulating ring can be made of silicon oxide, or other materials such as silicon nitride.

The sensitive electrode is mainly composed of three electrodes arranged according to cathode 104-anode 107-cathode 109 and an insulating layer 105 between the electrodes. The electrodes are Pt electrodes fixed in the flow channel 110 filled with electrolyte solution. The flow channel 110 refers to the flow channel 110 where the sensitive electrode is packaged, as shown in FIG. 1 . The electrolyte solution fills the pores of the anode and is distributed on the front cathode 104 , the surface of the back cathode 109 and the surface of the anode 107 . In the present invention, a 0.3V voltage is connected to the anode voltage access point 1 (102), and the voltage is introduced into the low-resistance silicon 108 through the Pt sputtered on the side wall of the anode access hole 101, and the low-resistance silicon 108 is conductively transmitted to the side wall of the flow channel The anode 107 and the two cathodes are directly drawn from the front and back respectively. By measuring the resistance between the anode voltage access point 1 ( 102 ) and the access point 2 ( 103 ), the input resistance of the 0.3V voltage from the access point to the anode 107 can be approximately characterized.

Through this method of using the support layer silicon to connect to the anode voltage, the problem that the electrode needs to be designed from the surface and the metal lead is sputtered is solved, and the complexity of the process is reduced. At the same time, the surface does not need to occupy the area of the cathode, which increases the utilization of the surface area. , increasing the cathode area. When there is a voltage difference between the cathode and the anode, the ions in the electrolyte solution react at the anode and the cathode respectively to complete the charge transfer between the cathode and the anode. When there is mechanical movement in the electrolyte solution, the distribution of ions around the electrodes is unbalanced, resulting in an unbalanced current output from the two cathodes. By calculating the differential current output by the cathodes, an electrical signal proportional to the external input motion signal can be obtained.

Fig. 2 is a MEMS process flow chart of the sensitive unit of the electrochemical vibration sensor proposed by the present invention. Specific steps are as follows:

Step (1): Select a four-inch silicon wafer with a resistivity of 0.0015Ω.cm and a thickness of 200 μm, boil acid and water to clean the silicon wafer. The silicon chip is low-resistance silicon 108 .

Step (2): growing silicon oxide with a thickness of 700 nm on the surface of the silicon wafer as the insulating layer 105 by means of thermal oxygen.

Step (3): After cleaning the silicon wafer with oxygen, use positive photoresist AZ1500 to remove the glue on the front side of the silicon wafer, pre-baking, exposing, and developing. A first region, a second region, and a plurality of mutually insulated anode access surfaces on the first region are formed separated by insulating bands.

Pt

Step (4): growing Ti on the front side of the silicon wafer using electron beam evaporation process

Pt

Step (5): Use acetone to perform a stripping process to remove the photoresist and the metal on the glue, leaving the metal as the front cathode 104 and the anode access surface with the metal layer.

Step (6): After cleaning the silicon wafer with oxygen, use the positive photoresist AZ1500 to remove the glue on the back of the silicon wafer, pre-baking, engraving on the back, and developing. Process parameters are consistent with step (3). A third area, a fourth area, and a plurality of mutually insulated anode access surfaces on the third area are formed separated by insulating bands.

Pt

Step (7): Growing Ti on the back of the silicon wafer using electron beam evaporation

Pt

Step (8): Use acetone to perform a stripping process to remove the photoresist and the metal on the glue, leaving the metal as the cathode 109 on the back side. The metal pattern is completely consistent with the front side to ensure the consistency of the two cathode structures. At the same time, an anode access surface with a metal layer is formed.

Step (9): Using the positive photoresist AZ4620, the front side of the silicon wafer is sprayed, pre-baked, overlaid on the front side, and developed.

Step (10): Using the photoresist in step (9) as a mask, use (RIE) reactive ion etching process to etch the silicon oxide on the front side, and then use (DRIE) deep reactive ion etching process to etch silicon, Finally, RIE process is used to etch the silicon oxide on the back side to form the sensitive unit channel hole (106) and the anode access hole. Use acetone to remove remaining photoresist.

Step (11): Exposing and developing a dry film on the front side of the silicon wafer to cover the position of the cathode 104 pattern and the insulating ring on the front side. The anode access hole 101 and the anode voltage access points (102, 103) need to be completely exposed, so that the side walls of the anode access hole 101 and the metal on the surface (102, 103) of the access voltage point are fully connected during sputtering.

Pt

Step (12): Sputter Ti from the front side of the silicon wafer using a sputtering process

Pt

Step (13): Stripping with NaOH solution to remove the dry film and metal, leaving the anode 107 on the side wall of the channel hole 106 of the sensitive unit. At the same time, the metal connection between the anode voltage access point (102, 103) and the low-resistance silicon 108 is completed, forming a path from the voltage access point 102 to the anode 107 where the electrolyte reacts.

In some embodiments of the present invention, other materials such as silicon nitride can be used as the insulating layer material;

In some embodiments of the present invention, the silicon oxide of the insulating layer can be fabricated using a thermal oxygen process, or can be deposited using a PECVD method.

In some embodiments of the present invention, the shape of the flow channel hole may be a square shape, and the flow channel hole distribution of the chip flow channel part may be circular or square. In some embodiments of the present invention, the transition electrode material Ti can also use other metals that are not easy to fall off from the silicon surface, such as Cr.

In some embodiments of the present invention, the silicon wafer used may be N-type silicon or P-type silicon.

Parts not described in detail in the present invention belong to the known techniques of those skilled in the art. The above-mentioned embodiments are only descriptions of the preferred implementations of the present invention, and the preferred embodiments do not exhaustively describe all the details, nor limit the invention to the described specific implementations. Without departing from the design spirit of the present invention, various modifications and improvements to the technical solution of the present invention by those skilled in the art shall fall within the scope of protection determined by the claims of the present invention.

Claims (10)

1. The sensitive electrode of the MEMS electrochemical vibration sensor based on silicon conduction is characterized by comprising a substrate, a first insulating layer, a second insulating layer, a plurality of flow channel holes, a first cathode, a flow channel hole side wall anode, a second cathode, an anode access hole and an anode voltage access position;

the substrate has a first surface and a second surface opposite to each other;

a first insulating layer formed on the first surface;

a second insulating layer formed on the second surface;

the first insulating layer is divided into a first area and a second area which are arranged in an insulating mode; the first region comprises a plurality of anode access surfaces;

the second insulating layer is divided into a third area and a fourth area which are arranged in an insulating mode; the third region comprises a plurality of anode access faces;

each anode access surface is provided with an anode voltage access part;

in the first region, each anode access surface is provided with at least one anode access hole penetrating to the anode access surface of the third region, and the anode access hole penetrates through the first insulating layer, the substrate and the second insulating layer;

the first cathode is formed on the second area, and an insulating ring distributed along the periphery of the runner hole is arranged between the first cathode and the runner hole;

a plurality of flow channel holes in the second region, the flow channel holes penetrating through the first insulating layer, the substrate and the second insulating layer, the flow channel holes being in the fourth region at an exit of the second insulating layer;

the second cathode is formed on the fourth area, and an insulating ring distributed along the periphery of the runner hole is arranged between the second cathode and the runner hole;

the anode is formed on the inner side wall of the runner hole and is respectively insulated from the first cathode and the second cathode;

the manufacturing method of the sensitive electrode comprises the following steps:

step (1): selecting and cleaning a substrate;

step (2): respectively forming a first insulating layer and a second insulating layer on the first surface and the second surface of the substrate;

and (3): photoresist is used, photoresist spinning, prebaking, exposure and development are carried out on the first insulating layer, and a first area and a second area which are separated by an insulating tape and a plurality of anode access surfaces which are arranged on the first area in an insulating mode are formed;

and (4): growing a first cathode metal layer on the second region of the first insulating layer; simultaneously growing metal layers on a plurality of anode access surfaces of the first area respectively;

and (5): removing the metal on the photoresist and the glue to form a first cathode and an anode access surface with a metal layer;

and (6): photoresist is used, spin coating, prebaking, alignment and development are carried out on the second surface of the substrate, the technological parameters are consistent with those in the step (3), and a third area and a fourth area which are separated by an insulating tape and a plurality of anode access surfaces which are arranged on the third area in an insulating mode are formed;

and (7): growing a second cathode metal layer on a fourth region on the second insulating layer; simultaneously growing metal layers on the plurality of anode access surfaces of the third area respectively;

and (8): removing the metal on the photoresist and the glue to form a second cathode and an anode access surface with a metal layer;

and (9): photoresist is used, spin coating, prebaking, front alignment and developing are carried out on the first insulating layer;

step (10): etching the first insulating layer by taking the photoresist in the step (9) as a mask, then etching the substrate, and finally etching the second insulating layer to form a flow channel hole and an anode access hole;

step (11): exposing and developing on the first insulating layer by using a dry film, and covering the first cathode pattern and the position of the insulating arrangement; the anode access hole and the anode access position need to be completely exposed, so that metal on the side wall of the anode access hole and the surface of the anode access position are fully connected during sputtering;

step (12): sputtering a metal from the first insulating layer using a sputtering process;

step (13): removing the dry film and the metal to form a runner hole side wall anode; and simultaneously, completing the metal connection from the anode access position to the substrate to form a passage from the voltage access position to the anode of the electrolyte for reaction.

2. The sensing electrode of claim 1, wherein the interior sidewall of the anode access hole is sputtered with metal.

3. The sensing electrode of claim 1, wherein the metal is Pt.

4. The sensing electrode of claim 1, wherein the insulating layer material is selected from silicon oxide or silicon nitride.

5. The sensing electrode of claim 1, wherein the flow channel aperture distribution is circular or square.

6. The sensing electrode of claim 1, wherein the substrate is a silicon wafer; the silicon wafer is selected from N-type silicon or P-type silicon.

7. The sensing electrode of claim 1, wherein the anode access surface has a metal layer thereon; the inner side wall of the anode access hole is provided with a metal layer; and the metal on the inner side wall of the anode access hole is connected with the metal on the surface of the anode voltage access position.

8. The sensing electrode according to claim 1, wherein the insulating layer is fabricated using a thermal oxygen process or deposited using a PECVD method.

9. The sensing electrode of claim 1, wherein in step (8), the second cathodic metal pattern is identical to the first cathodic metal pattern.

10. A MEMS electrochemical vibration sensor based on silicon conduction, comprising a sensitive electrode according to any of claims 1 to 9.

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