A structure optimization design method of a silicon-based resonant pressure sensor

Abstract

The application discloses a structure optimization design method of a silicon-based resonant pressure sensor, which comprises the following steps: obtaining the maximum stress variation amount Delta sigma and the maximum deformation variation amount Delta gamma of the square units in the initial device layer after removing the i-th square unit, i=1...I; then obtaining the evolution parameter C of the i-th square unit according to the maximum stress sigma0 and the maximum deformation gamma0 of all the square units in the initial device layer; performing three evolutions on the device layer based on the method, obtaining the device layer after the third structure evolution, determining the position and the basic shape of the resonant structure, determining the final device layer of the resonant pressure sensor, and completing the design of the resonant pressure sensor. The three evolutions on the device layer can solve the problem that the linearity of the sensor in a large pressure range may decrease with the increase of the sensitivity, leading to the nonlinear change of the frequency response, and the application has the characteristics of high sensitivity and low nonlinear error, and high measurement accuracy.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of micro-mechanical electronic (MEMS) sensors, in particular to a structure optimization design method of a silicon-based resonant pressure sensor. BACKGROUND

[0002] Compared with traditional piezoresistive and piezoelectric pressure sensors, resonant pressure sensors have unique advantages in measurement accuracy, stability and long-term reliability. The working principle of resonant pressure sensors is based on detecting the change of resonator resonance frequency, which indirectly reflects the change of external pressure, thereby realizing high-precision pressure measurement. This characteristic makes resonant pressure sensors irreplaceable in applications that require high precision and long-term stability. The advantages of resonant pressure sensors not only lie in their high-precision measurement capability, but also in the characteristics of their digital output signals, making the interface between the sensor and the computer or digital instrument more convenient. This high precision and digital output characteristic makes it widely used in high-demand applications such as weather monitoring, atmospheric data acquisition, weapon equipment monitoring and industrial process control. In addition, due to the high anti-interference ability, long service life and low maintenance cost of resonant pressure sensors, their demand in high-precision and high-reliability applications is increasing year by year.

[0003] However, despite the significant advantages of resonant pressure sensors in many applications, their development still faces some technical challenges, especially the balance between high sensitivity and low non-linear error. The sensitivity of resonant sensors is usually proportional to the strength of the response of their resonant frequency to pressure changes. In order to improve sensitivity, more sensitive resonator structures or high-performance materials are usually designed. However, with the improvement of sensitivity, the linearity of the sensor in a larger pressure range may decrease, leading to non-linear changes in frequency response and affecting the accuracy of measurement. SUMMARY

[0004] The present application discloses a structure optimization design method of a silicon-based resonant pressure sensor to overcome the above technical problems.

[0005] In order to achieve the above purpose, the technical scheme of the present application is:

[0006] A structure optimization design method of a silicon-based resonant pressure sensor, comprising the following steps:

[0007] S1: using finite element simulation software COMSOL to model the silicon substrate, isolation layer and initial device layer of the pressure-sensitive chip; and dividing the initial device layer into multiple square units of equal size; setting the constraints and boundary conditions of the pressure-sensitive chip;

[0008] S2: applying a load perpendicular to the initial device layer to the pressure-sensitive chip, obtaining the maximum stress σ0 and the maximum deformation γ0 of all the square units in the initial device layer;

[0009] S3: obtaining the maximum stress variation Δσ and the maximum deformation variation Δγ of the square units in the initial device layer after removing the i-th, i = 1…I, square unit, and further obtaining the evolution parameter C of the i-th square unit according to the maximum stress σ0 and the maximum deformation γ0 of all the square units in the initial device layer; i represents the index of the square unit in the initial device layer; I represents the total number of the square units in the initial device layer;

[0010] S4: performing the first structure evolution on the initial device layer according to the evolution parameter C of the i-th square unit, and obtaining the device layer after the first structure evolution;

[0011] S5: re-executing S2-S4 based on the device layer after the first structure evolution, and obtaining the device layer after the second structure evolution;

[0012] S6: re-executing S2-S4 based on the device layer after the second structure evolution, and obtaining the device layer after the third structure evolution;

[0013] S7: determining the position and the basic shape of the resonant structure according to the device layer after the third structure evolution, determining the device layer of the final resonant pressure sensor, and completing the design of the resonant pressure sensor.

[0014] Further, the formula for obtaining the evolution parameter C of the i-th square unit is as follows:

[0015]

[0016] In the formula, C represents the evolution parameter; Δσ represents the variation of the maximum stress of the square unit in the initial device layer after removing the i-th square unit; Δγ represents the variation of the maximum deformation of the initial device layer after removing the i-th square unit; σ0 represents the maximum stress of all the square units in the initial device layer; and γ0 represents the maximum deformation of all the square units in the initial device layer.

[0017] Further, the method for obtaining the device layer after the first structure evolution is as follows:

[0018] If the evolution parameter C of the i-th square unit is not greater than 1, the i-th square unit is removed from the initial device layer;

[0019] All the square units with the evolution parameter C greater than 1 constitute the device layer after the first structure evolution.

[0020] Further, the device layer of the final resonant pressure sensor comprises a resonant structure;

[0021] The resonant structure comprises a central resonator and two edge resonators;

[0022] The two edge resonators are arranged on both sides of the central resonator;

[0023] The central resonator comprises a first resonant beam, two first silicon islands, two first resonator electrodes, two first excitation electrodes, and a plurality of first detection electrodes;

[0024] The two ends of the first resonant beam are fixedly connected with the two first silicon islands, respectively;

[0025] The two first resonator electrodes are fixedly arranged on both sides of the first resonant beam;

[0026] The two first excitation electrodes are connected with the two first resonator electrodes through an electric field, respectively;

[0027] The plurality of first detection electrodes are uniformly arranged on both sides of the first resonant beam and connected with the first resonator electrodes through an electric field;

[0028] The first detection electrodes are fixedly connected with a first metal electrode through a first signal lead-out beam;

[0029] The edge resonator comprises a second resonant beam, two second silicon islands, two second resonator electrodes, two second excitation electrodes, and a plurality of second detection electrodes;

[0030] The two ends of the second resonant beam are fixedly connected with the two second silicon islands, respectively; and the two second resonator electrodes are fixedly arranged on both sides of the second resonant beam;

[0031] The two second excitation electrodes are connected with the two second resonator electrodes through an electric field, respectively;

[0032] The plurality of second detection electrodes are uniformly arranged on both sides of the second resonant beam and connected with the second resonator electrodes through an electric field;

[0033] The second detection electrodes are fixedly connected with a second metal electrode through a second signal lead-out beam.

[0034] Further, the pressure-sensitive chip is processed by an SOI process.

[0035] Beneficial effects: the structure optimization design method of the silicon-based resonant pressure sensor of the application, by obtaining the maximum stress variation amount Delta sigma and the maximum deformation variation amount Delta gamma of the square unit in the initial device layer after removing the i, i=1…I square units, and then according to the maximum stress sigma0 and the maximum deformation gamma0 in all square units in the initial device layer, the evolution parameter C of the i square unit is obtained; based on this method, the device layer is evolved three times, and after obtaining the device layer after the third structure evolution, the position and basic shape of the resonant structure are determined, so as to determine the final device layer of the resonant pressure sensor, and the design of the resonant pressure sensor is completed. The three evolutions of the device layer can solve the problem that with the improvement of the sensitivity, the linearity of the sensor in a large pressure range may decrease, resulting in the nonlinear change of the frequency response, and has the characteristics of high sensitivity and low nonlinear error, and high measurement accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0037] Figure 1 The flow chart of the structure optimization design method of the silicon-based resonant pressure sensor of the application;

[0038] Figure 2 The overall schematic diagram of the MEMS pressure sensor in the embodiment of the application;

[0039] Figure 3 The device layer structure schematic diagram of the MEMS pressure sensor in the embodiment of the application;

[0040] Figure 4 The Figure 3 The resonant structure amplification schematic diagram of the MEMS pressure sensor in B of the application;

[0041] Figure 5 The Figure 3 The structure cross-sectional view of the MEMS pressure sensor in A of the application;

[0042] Figure 6 The flow chart of the structure design method of the MEMS pressure sensor in the embodiment of the application;

[0043] Figure 7 The resonant structure evolution process flow chart of the device layer of the MEMS pressure sensor in the embodiment of the application.

[0044] Wherein: 1, silicon substrate; 2, silicon dioxide insulating isolation layer; 3, single crystal silicon device layer; 4, glass substrate; 5, center resonator; 51, first resonant beam; 52, first silicon island; 53, first resonator electrode, 54, first excitation electrode; 55, first detection electrode; 56, first metal electrode; 57, first signal lead-out beam; 6, edge resonator; 61, second resonant beam; 62, second silicon island; 63, second resonator electrode; 64, second excitation electrode; 65, second detection electrode; 66, second metal electrode; 67, second signal lead-out beam. DETAILED DESCRIPTION

[0045] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0046] The embodiment introduces a structure optimization design method of a silicon-based resonant pressure sensor, as shown in Figure 1 and Figure 6 , comprising the following steps:

[0047] S1: using finite element simulation software COMSOL to model the silicon substrate 1, isolation layer 2 and initial device layer 3 of the pressure-sensitive chip processed by SOI process; and dividing the initial device layer 3 into multiple square units of equal size; setting the constraints and boundary conditions of the pressure-sensitive chip;

[0048] Specifically, the pressure-sensitive chip of the embodiment comprises a silicon substrate, a silicon dioxide insulating isolation layer, a single crystal silicon device layer and a glass substrate 4 arranged from top to bottom; the pressure-sensitive chip of the MEMS pressure sensor of the embodiment is processed by SOI process, a layer of silicon dioxide insulating isolation layer 2 is covered on the silicon substrate 1, then a thin single crystal silicon device layer is formed on the insulating layer, and resonators and excitation electrodes and other structures are processed and manufactured on the device layer by etching method. The glass substrate is etched and the glass substrate and the single crystal silicon of the device layer are anodically bonded to form a vacuum cavity, and finally the sensor silicon substrate is etched to form a pressure-sensitive diaphragm, the isolation layer is etched and Al metal is deposited to form a metal electrode, as shown in Figure 2 .

[0049] Specifically, the optimization method can be implemented by finite element analysis software COMSOL, and the implementation steps are as follows:

[0050] Specifically, the pressure sensor structure proposed in the embodiment is gradually optimized by an evolution method, and the sensitivity is maximized under the condition of ensuring linearity. The structure optimization design of the silicon-based resonant pressure sensor is realized by using a finite element simulation software COMSOL. First, the silicon substrate 1, the isolation layer 2 and the initial device layer 3 of the pressure-sensitive chip processed based on the SOI process are modeled. In the modeling, the shape of the device layer can be arbitrarily optimized, and the silicon substrate and the isolation layer remain unchanged in the fixed structure. Then, the initial device layer is divided into square cells of equal size for subsequent processing.

[0051] Specifically, the constraint and boundary condition setting of the embodiment adopts a solid mechanics model, in which the edge of the pressure-sensitive chip is set as a fixed constraint to ensure the edge of the initial device layer fixed. After completing the boundary condition setting, the "sweep" method in the COMSOL software is used to construct the grid of the sensor model. Since the device layer 3 of the pressure-sensitive chip is divided into multiple square cells of equal size in the embodiment, the grid of each square cell of the device layer can be independently divided, so that when any cell is removed in the subsequent step, the grid structure of other cells will not be affected.

[0052] S2: A load perpendicular to the initial device layer is applied to the pressure-sensitive chip to obtain the maximum stress σ0 and the maximum deformation γ0 in all square cells of the initial device layer;

[0053] S3: Obtain the maximum stress change Δσ and the maximum deformation change Δγ of the square cells in the initial device layer after removing the i-th, i=1…I square cell, and then obtain the evolution parameter C of the i-th square cell according to the maximum stress σ0 and the maximum deformation γ0 in all square cells of the initial device layer; i represents the index of the square cell in the initial device layer; I represents the total number of square cells in the initial device layer;

[0054] Preferably, the formula for obtaining the evolution parameter C of the i-th square cell is as follows:

[0055]

[0056] In the formula, C represents the evolution parameter; Δσ represents the change of the maximum stress of the square cell in the initial device layer after removing the i-th square cell; Δγ represents the change of the maximum deformation of the initial device layer after removing the i-th square cell; σ0 represents the maximum stress in all square cells of the initial device layer; γ0 represents the maximum deformation in all square cells of the initial device layer;

[0057] S4: performing first structure evolution on the initial device layer according to the evolution parameter C of the i-th square unit, to obtain a device layer after first structure evolution;

[0058] Preferably, the device layer after first structure evolution is obtained by the following method:

[0059] If the evolution parameter C of the i-th square unit is not greater than 1, the i-th square unit is removed from the initial device layer;

[0060] All square units with evolution parameter C greater than 1 constitute the device layer after first structure evolution.

[0061] S5: re-executing S2-S4 based on the device layer after first structure evolution, to obtain a device layer after second structure evolution;

[0062] S6: re-executing S2-S4 based on the device layer after second structure evolution, to obtain a device layer after third structure evolution;

[0063] Specifically, in order to improve the sensitivity to the maximum extent while ensuring the linearity, the embodiment sets the evolution parameter C to represent the ratio between the relative change amount of the maximum stress of the pressure-sensitive chip after removing a unit and the relative change amount of the maximum deformation, calculates the evolution parameter of each unit, and determines whether to retain the unit according to the value of the evolution parameter. Wherein, removing a unit will increase the maximum stress σ and the maximum deformation γ of all square units of the device layer, assuming that after removing a unit, the maximum stress change amount of the device layer is Δσ, the maximum deformation change amount of the device layer is Δγ, and the initial maximum stress and maximum deformation of the device layer are σ0 and γ0 (i.e. the maximum stress and maximum strain of the device layer without removing the square unit). The optimization goal is to maximize the maximum stress σ while minimizing the maximum deformation γ, so the evolution parameter C is defined as: Analyzing the evolution parameter C of each unit and removing the unit with evolution parameter not greater than 1 can realize low deflection and high stress of the device layer, thereby improving the sensitivity of the pressure sensor without sacrificing linearity;

[0064] Specifically, after removing the square unit with evolution parameter not greater than 1, the device layer after first structure evolution is re-modeled to complete the first structure evolution. The process of physical field setting and evolution parameter calculation is repeated for three iterations of optimization. After the third evolution, the position and basic shape of the resonant structure are determined, and the final device layer of the resonant pressure sensor includes: selecting the maximum stress region to set the resonant beam, and arranging silicon islands, excitation electrodes and detection electrodes on both sides. Finally, the signal lead beam and metal electrodes are designed, and the structure design of the device layer is completed.

[0065] S7: determining the position and basic shape of the resonant structure according to the device layer after the third structural evolution, to determine the final device layer of the resonant pressure sensor, and completing the design of the resonant pressure sensor.

[0066] Specifically, after removing the square cells with an evolution parameter not greater than 1 from the initial device layer, the embodiment re-models the device layer, i.e., completes the first structural evolution process of the pressure-sensitive chip, and repeats the structural evolution processes of steps S2 and S4. After the third structural evolution, the basic shape and position of the resonant structure are determined. Further, based on the conventional technology in the field, a person skilled in the art determines the final shape of the resonant structure according to the basic shape of the resonant structure, as shown in the figure, and further completes the design of the final device layer of the resonant pressure-sensitive chip. Figure 7

[0067] Specifically, according to the position of the resonant structure determined in step S7, the embodiment sets a center resonator and two edge resonators, the structure of each resonator is set to two silicon islands fixing a resonant beam at the center of the resonator, and excitation electrodes and detection electrodes are arranged on both sides of the resonant beam. Finally, a signal lead-out beam and a metal electrode are designed to complete the structural design of the device layer.

[0068] Preferably, the final device layer of the resonant pressure sensor comprises a resonant structure.

[0069] The resonant structure comprises a center resonator 5 and two edge resonators 6; the two edge resonators 6 are arranged on both sides of the center resonator 5; the center resonator 5 comprises a first resonant beam 51, two first silicon islands 52, two first resonator electrodes 53, two first excitation electrodes 54, and a plurality of first detection electrodes 55; the two ends of the first resonant beam 51 are fixedly connected with the two first silicon islands 52, respectively; the two first resonator electrodes 53 are fixedly arranged on both sides of the first resonant beam 51; the two first excitation electrodes 54 are connected with the two first resonator electrodes 53 through an electric field, respectively; the plurality of first detection electrodes 55 are uniformly arranged on both sides of the first resonant beam 51 and connected with the first resonator electrodes 53 through an electric field; and the first detection electrodes 55 are fixedly connected with a first metal electrode 56 through a first signal lead-out beam 57.

[0070] ​The edge resonator 6 comprises a second resonant beam 61, two second silicon islands 62, two second resonator electrodes 63, two second excitation electrodes 64, and a plurality of second detection electrodes 65. The two ends of the second resonant beam 61 are fixedly connected with the two second silicon islands 62 respectively. The two second resonator electrodes 63 are fixedly arranged on the two sides of the second resonant beam 61. The two second excitation electrodes 64 are electrically connected with the two second resonator electrodes 63 respectively. The plurality of second detection electrodes 65 are uniformly arranged on the two sides of the second resonant beam 61 and electrically connected with the second resonator electrodes 63. The second detection electrodes 65 are fixedly connected with a second metal electrode 66 through a second signal lead-out beam 67.

[0071] Specifically, the first excitation electrode 54 and the second excitation electrode 64 of the embodiment are connected with the back-end processing circuit through the metal electrode.

[0072] Specifically, the center resonator and the edge resonator of the embodiment are fixedly arranged on one side of the isolation layer 2. The sensitive element of the resonant pressure sensor is mainly concentrated in the device layer 3 and mainly comprises a resonant structure, an excitation structure and a detection structure, as shown in Figure 3 , Figure 4 , Figure 5 When the resonant pressure sensor is subjected to pressure, the pressure acts on the pressure-sensitive diaphragm, the pressure-sensitive chip as a whole deforms, the stress is transmitted to the resonant beam, and the resonant beam of the center resonator 5 and the two edge resonators 6 is subjected to stress, so that the natural resonant frequency of the resonant beam changes. The first excitation electrode / second excitation electrode outputs an alternating excitation signal, the first resonator / second resonator is subjected to electrostatic force to produce displacement, and the first detection electrode / second detection electrode arranged on the two sides of the first resonator / second resonator detects the displacement of the first resonator / second resonator and converts it into a capacitance signal.

[0073] Specifically, in the embodiment, the resonator electrodes are arranged on the two sides of the resonant beam and a direct current voltage is applied, the excitation electrode applies an alternating voltage, the resonator is subjected to alternating coulomb force to produce deformation, and the capacitance formed by the resonator and the detection electrodes on the two sides thereof changes. When the resonator enters a resonant state, the resonant frequency of the resonator can be measured by analyzing the capacitance signal output by the detection electrode, and then the pressure borne by the pressure-sensitive chip is analyzed.

[0074] Specifically, the silicon substrate 1 of the embodiment is etched to form a pressure-sensitive diaphragm, the pressure to be measured applied on the resonant pressure sensor is first directly applied on the silicon substrate, and then transmitted to the isolation layer 2 and the device layer 3, the device layer 3 is used to convert the pressure into a resonant signal for measurement, and the glass substrate 4 is used to support other structures of the pressure sensor, the glass substrate is etched and deposited with a getter to form a vacuum cavity, so that the pressure-sensitive diaphragm only bears the pressure to be measured.

[0075] Specifically, the embodiment determines the position and basic shape of the resonant structure by performing three structural evolutions on the device layer, optimizes the structure of the device layer, and thereby improves the performance of the resonant pressure sensor, including the sensitivity and linearity thereof. Since there is a certain trade-off relationship between the sensitivity and linearity of the resonant pressure sensor, increasing the sensitivity requires the sensor to bear as much stress as possible under the same load, which usually requires the pressure-sensitive chip to produce a large degree of strain. However, a large strain may cause the nonlinearity of the output signal, so in order to ensure the linearity, the design of the sensor often needs to limit the strain of the chip. In order to balance between the two, the resonant structure of the sensor needs to be optimized. The embodiment performs three structural evolutions on the device layer, and gradually eliminates part of the structure through evolution, so as to maximize the sensitivity while ensuring the linearity. Through accurate design and optimization, the linearity of the sensor can be improved without significantly sacrificing the sensitivity, thereby realizing a high-performance resonant pressure sensor.

[0076] The embodiment has the following beneficial effects:

[0077] The structural optimization design method of the silicon-based resonant pressure sensor of the embodiment provides a resonant pressure sensor structure that maximizes the sensitivity without sacrificing the linearity. The COMSOL finite element analysis software is used to complete the structural design of the device layer. In the design process, small deformation and high stress are used as indicators to gradually evolve the structure of the device layer. The maximum stress is increased under the condition of reducing the deformation degree of the sensor, the sensitivity of the resonant pressure sensor is maximized under the condition of ensuring the linearity, and the contradiction between high sensitivity and high linearity of the sensor is solved.

[0078] The sensor of the embodiment uses electrostatic excitation and capacitance detection. Within a fixed pressure range, there is a good linear relationship between the resonant frequency of the resonator and the external pressure. By analyzing the resonant frequency of the resonator, the external pressure can be detected. The embodiment aims to balance the sensitivity and linearity of the resonant pressure sensor. The device layer is divided into multiple square units, the evolution parameter size of each unit is analyzed to determine whether to retain the unit, and after three evolutions, the sensor structure detail design is completed according to the evolution result. The obtained resonant structure can improve the sensitivity and linearity of the sensor at the same time.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for the structural optimization of a silicon-based resonant pressure sensor, characterized in that, The method comprises the following steps: S1: using finite element simulation software COMSOL to model the silicon substrate, isolation layer and initial device layer of the pressure-sensitive chip; and dividing the initial device layer into multiple square units of equal size; setting the constraints and boundary conditions of the pressure-sensitive chip; S2: applying a load perpendicular to the initial device layer to the pressure-sensitive chip, obtaining the maximum stress in all of the square cells in the initial device layer and the maximum deformation ; S3: obtaining a maximum stress variation of the square cells in the initial device layer after removing the i-th, i = 1…I, square cell and the maximum deformation variation Δγ, and then according to the maximum stress and the maximum deformation of all the square cells in the initial device layer, obtaining the evolution parameter of the i-th square cell C ; i represents the index of the square cell in the initial device layer; I represents the total number of the square cells in the initial device layer; obtaining the evolution parameter of the ith square cell C The formula used is as follows: C= / S4: the evolution parameter of the i-th square unit C performing a first structure evolution on the initial device layer to obtain a device layer after the first structure evolution; S5: based on the device layer after the first structure evolution, re-executing S2-S4 to obtain the device layer after the second structure evolution; S6: based on the device layer after the second structure evolution, re-executing S2-S4 to obtain the device layer after the third structure evolution; S7: determining the position and basic shape of the resonant structure according to the device layer after the third structure evolution, to determine the device layer of the final resonant pressure sensor, and completing the design of the resonant pressure sensor; The device layer of the final resonant pressure sensor comprises a resonant structure. The resonant structure comprises a central resonator (5) and two edge resonators (6). The two edge resonators (6) are arranged on the two sides of the central resonator (5). The central resonator (5) comprises a first resonant beam (51), two first silicon islands (52), two first resonator electrodes (53), two first excitation electrodes (54) and a plurality of first detection electrodes (55). The two ends of the first resonant beam (51) are fixedly connected with the two first silicon islands (52) respectively. The two first resonator electrodes (53) are fixedly arranged on the two sides of the first resonant beam (51). The two first excitation electrodes (54) are connected with the two first resonator electrodes (53) through an electric field respectively. The plurality of first detection electrodes (55) are uniformly arranged on the two sides of the first resonant beam (51) and connected with the first resonator electrodes (53) through an electric field. The first detection electrodes (55) are fixedly connected with a first metal electrode (56) through a first signal lead-out beam (57). The edge resonator (6) comprises a second resonant beam (61), two second silicon islands (62), two second resonator electrodes (63), two second excitation electrodes (64) and a plurality of second detection electrodes (65). The two ends of the second resonant beam (61) are fixedly connected with the two second silicon islands (62) respectively. The two second excitation electrodes (64) are connected with the two second resonator electrodes (63) through an electric field respectively. The plurality of second detection electrodes (65) are uniformly arranged on the two sides of the second resonant beam (61) and connected with the second resonator electrodes (63) through an electric field. The second detection electrodes (65) are fixedly connected with a second metal electrode (66) through a second signal lead-out beam (67).

2. The method of claim 1, wherein the method is characterized by: The device layer after the first structure evolution is obtained by the following method: If the evolution parameter of the i-th square unit C If the value is not greater than 1, then the i-th square cell is removed from the initial device layer; then all the evolution parameters C The square cells with a size larger than 1 constitute the device layer after the first structural evolution.

3. The method of claim 1, wherein the method is characterized by: The pressure-sensitive chip is processed by an SOI process.

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