Angular velocity sensing device based on piezoresistance-avalanche effect and MEMS gyroscope

Abstract

The utility model provides an angular velocity sensing device based on a piezoresistance-avalanche effect and an MEMS gyroscope, and relates to the technical field of MEMS sensing. The angular velocity sensing device comprises a base, an oscillation driving assembly arranged on the base and an oscillation transmission assembly connected between the oscillation driving assembly and the base. The internal structure of the oscillation transmission assembly is provided with a connecting beam, and / or the connecting beam is connected between the oscillation transmission assembly and the base; the oscillation driving assembly is used for driving the oscillation transmission assembly to oscillate in the preset direction, the connecting beam is provided with a stress sensing area capable of sensing the oscillation, and the stress sensing area is provided with an effect junction with a piezoresistance-avalanche effect. The MEMS gyroscope comprises a reverse bias power supply, a measuring assembly, a control assembly and the angular velocity sensing device. The angular velocity sensing device applied to the gyroscope has the characteristics of high measurement sensitivity, simple structure, low manufacturing cost and small volume.

Description

TECHNICAL FIELD

[0001] The utility model relates to microcomputer electromechanical sensing technical field especially relates to a kind of angular velocity sensing device and MEMS gyroscope based on piezoresistance-avalanche effect. BACKGROUND

[0002] MEMS (Micro-Electro-Mechanical System) gyroscope has the advantages of small size, low cost, etc., is widely used in the field of automobile, consumer electronics, etc. Mainly includes capacitive gyroscope and piezoresistive gyroscope, wherein, capacitive gyroscope has higher requirement to manufacturing process and poor measurement sensitivity;Piezoresistive gyroscope has low measurement sensitivity, and its structure is complex, and its size is large. Therefore, there is an urgent need for a gyroscope that can simultaneously satisfy high measurement sensitivity, simple structure, low manufacturing cost and small size. SUMMARY

[0003] The utility model aims at providing a kind of angular velocity sensing device and MEMS gyroscope based on piezoresistance-avalanche effect, to solve the technical problems of low measurement sensitivity, complex structure, high manufacturing cost and large size of existing gyroscope.

[0004] To solve the above problems, the utility model provides a kind of angular velocity sensing device based on piezoresistance-avalanche effect, including pedestal, oscillation drive assembly arranged on the pedestal and oscillation transmission assembly connected between the two;The internal structure of the oscillation transmission assembly has a connecting beam, and / or the oscillation transmission assembly is connected with the connecting beam between the pedestal;

[0005] The oscillation drive assembly is used to drive the oscillation transmission assembly to oscillate along the preset direction, the connecting beam has stress sensing area capable of sensing the oscillation, and the stress sensing area is provided with effect junction with piezoresistance-avalanche effect.

[0006] Optionally, the connecting beam is multiple, and multiple connecting beams are dispersedly arranged on the oscillation transmission assembly.

[0007] Optionally, the oscillation transmission assembly is symmetrical structure, and multiple connecting beams are symmetrically arranged.

[0008] Optionally, the effect junction is PN junction.

[0009] Optionally, the connecting end region of the connecting beam is used as the stress sensing area.

[0010] Optionally, the base is provided with an anchor area, one end of at least part of the connecting beam is fixed to the oscillation transmission assembly, and the other end is fixed to the anchor area, the anchor area is provided with a first electrode and a second electrode, the first electrode is connected to the first end of the effect junction, and the second electrode is connected to the second end of the effect junction.

[0011] Optionally, the oscillation transmission assembly comprises:

[0012] The driving frame comprises two driving frame bodies which are symmetrically arranged about the Y direction and each of which is provided with an opening on one side, a connecting arm is connected between the first ends and the second ends of the two driving frame bodies in the Y direction, and the connecting arm is rotationally connected to the base at the symmetric position in the Y direction; and the outer side frame strips of the two driving frame bodies in the X direction are connected to the oscillation driving assembly, and the oscillation driving assembly is used to drive the driving frame to oscillate in the Y direction.

[0013] The Coriolis frame comprises two Coriolis frame bodies which are one-to-one correspondingly located in the two driving frame bodies, and an X unidirectional spring is connected between each of the two ends of the Coriolis frame body in the X direction and the corresponding driving frame body.

[0014] The detection frame comprises two detection frame bodies which are one-to-one correspondingly located in the two Coriolis frame bodies, and a Y unidirectional spring is connected between each of the two ends of the detection frame body in the Y direction and the corresponding Coriolis frame body, and a coupling spring is connected between the two detection frame bodies.

[0015] The two ends of the detection frame in the X direction and the base are connected by the connecting beam, and the outer side frame strips of the driving frame in the Y direction and the base are connected by the connecting beam.

[0016] Optionally, the angular velocity is calculated according to the following formula:

[0017]

[0018] In the formula, Ω Z is the angular velocity received by the angular velocity sensing device, rad / s; A s is the X direction displacement of the detection frame, m; A d is the Y direction displacement of the Coriolis frame, m; m d is the equivalent mass of the driving frame, kg; m c is the equivalent mass of the Coriolis frame, kg; m s is the equivalent mass of the detection frame, kg; f s is the modal frequency of the detection frame, Hz; f d is the modal frequency of the driving frame, Hz; f in is the frequency of the driving voltage, Hz; Qd Q is a quality factor associated with the frame and the damping s Q is a quality factor associated with the frame and the damping.

[0019] The utility model also provides a MEMS gyroscope, including reverse bias power supply, measurement subassembly, control component and above angular velocity sensing device, reverse bias power supply is connected in the two ends of effect junction of angular velocity sensing device, is used for applying reverse voltage to effect junction to make it enter breakdown state, measurement subassembly is connected to effect junction, is used for measuring breakdown electric parameter of effect junction, control component communication connection is in reverse bias power supply and measurement subassembly.

[0020] The angular velocity sensing device provided by the utility model can amplify and display the stress change of the stress sensing area according to the piezoresistance-avalanche effect of the effect junction through the initial breakdown electric parameter and the breakdown electric parameter change value with a large change amplitude, so as to improve the sensing sensitivity of the gyroscope to the angular velocity, and simultaneously consider the displacement of the oscillation transmission component, the angular velocity of the gyroscope, the Coriolis force, the driving voltage of the oscillation driving component, the stress of the stress sensing area, and the correlation between the initial breakdown electric parameter and the breakdown electric parameter change value, so that the angular velocity is more accurately obtained, and the angular velocity measurement sensitivity of the gyroscope is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the specific embodiments of the utility model or the technical solutions in the prior art, the drawings needed to be used in the specific embodiments or the prior art description will be briefly introduced as follows. Obviously, the drawings in the following description are some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0022] Figure 1 The angular velocity sensing device provided by the utility model is a top view schematic diagram when the angular velocity sensing device is in the form of double mass blocks.

[0023] Figure 2 The angular velocity sensing device provided by the utility model is a top view schematic diagram when the angular velocity sensing device is in the form of single mass block.

[0024] Figure 3 The angular velocity sensing device provided by the utility model is a top view schematic diagram when the angular velocity sensing device is in the form of butterfly structure.

[0025] Figure 4The flowchart of the angular velocity measurement method of the MEMS gyroscope is provided.

[0026] Marked with the following reference numerals:

[0027] 100-base; 200-oscillation driving assembly; 210-fixed comb tooth; 220-movable comb tooth; 300-oscillation transmission assembly; 310-driving frame; 311-driving frame body; 312-opening; 313-connecting arm; 320-Coriolis frame; 321-Coriolis frame body; 330-X one-way spring; 340-detection frame; 341-detection frame body; 342-coupling spring; 350-Y one-way spring; 360-transmission unit; 370-connecting unit; 400-connecting beam; 500-anchor area. DETAILED DESCRIPTION

[0028] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0029] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] The present embodiment provides an angular velocity sensing device based on piezoresistance-avalanche effect, which comprises a base, a driving frame, a detection frame, a transmission unit and a connecting unit. Figures 1-3As shown, the MEMS gyroscope comprises a base 100, an oscillation driving assembly 200 arranged on the base 100, and an oscillation transmission assembly 300 connected between the base 100 and the oscillation driving assembly 200; the internal structure of the oscillation transmission assembly 300 has a connecting beam 400, and / or the connecting beam 400 is connected between the oscillation transmission assembly 300 and the base 100; the oscillation driving assembly 200 is used to drive the oscillation transmission assembly 300 to perform oscillation movement along a preset direction; the connecting beam 400 has a stress sensing area capable of sensing the oscillation movement, and the stress sensing area is provided with an effect junction having a piezoresistance-avalanche effect.

[0032] The embodiment also provides a MEMS gyroscope, which comprises a reverse bias power supply, a measuring assembly, a control assembly and the angular velocity sensing device, the reverse bias power supply is connected to two ends of the effect junction in the angular velocity sensing device, and is used to apply a reverse voltage to the effect junction to make the effect junction enter a breakdown state; the measuring assembly is connected to the effect junction, and is used to measure a breakdown electrical parameter of the effect junction; and the control assembly is communicatively connected to the reverse bias power supply and the measuring assembly.

[0033] Figure 4 The embodiment also provides a flowchart of an angular velocity measurement method of the MEMS gyroscope. The measurement method comprises the following steps.

[0034] S402 adjusting the reverse bias power supply to apply a reverse voltage to the effect junction to make the effect junction enter a breakdown state, and adjusting the oscillation driving assembly 200 to drive the oscillation transmission assembly 300 to perform oscillation movement along a preset direction.

[0035] In use, the reverse voltage applied to the effect junction by the reverse bias power supply makes the effect junction enter a breakdown state, and the effect junction has a piezoresistance-avalanche effect in the breakdown state; the oscillation driving assembly 200 is started, and the oscillation transmission assembly 300 performs oscillation movement along a preset direction under the driving of the oscillation driving assembly 200; when the gyroscope is subjected to an angular velocity, under the dual action of the angular velocity and the oscillation movement along the preset direction, according to Euler-Bernoulli beam theory, the stress sensing area generates a corresponding stress, the stress can make the electron mobility and the energy band gap of the effect junction change, so that the breakdown electrical parameters such as the breakdown voltage and the breakdown current of the effect junction change greatly, and the mechanical stress of the stress sensing area is approximately linearly amplified, so that the breakdown electrical parameters of the effect junction have high sensitivity to the mechanical stress of the stress sensing area.

[0036] S404 the measuring assembly detects the breakdown electrical parameter of the effect junction and feeds back to the control assembly.

[0037] S406 the control assembly calculates the angular velocity according to the breakdown electrical parameter, the structure related parameter of the angular velocity sensing device and the driving voltage of the oscillation driving assembly 200.

[0038] The control component stores structure-related parameters related to the mechanical structure, connection circuit structure and environment of the angular velocity sensing device. The measuring component detects the breakdown electric parameters of the effect junction in real time and feeds back to the control component. The control component takes the breakdown electric parameters fed back by the measuring component when the gyroscope is not subjected to angular velocity and oscillation motion as initial breakdown electric parameters, and takes the breakdown electric parameters fed back by the measuring component and the change value of the initial breakdown electric parameters when the gyroscope is subjected to angular velocity under oscillation motion as breakdown electric parameter change values. The initial breakdown electric parameters and the breakdown electric parameter change values with large change amplitudes can amplify and represent the stress of the stress sensing area, and the structure-related parameters of the angular velocity sensing device and the driving voltage of the oscillation driving component 200 can associate the angular velocity with the stress.

[0039] Then, the control component calculates the stress of the connecting beam 400 according to the initial breakdown electric parameters, the breakdown electric parameter change values and the structure-related parameters of the angular velocity sensing device, and calculates the displacement motion information of the oscillation transmission component 300 according to the stress of the connecting beam 400, the structure-related parameters of the angular velocity sensing device and the driving voltage of the oscillation driving component 200, so as to obtain the Coriolis force received by the gyroscope and inversely deduce the angular velocity received by the gyroscope in combination with the displacement motion information of the oscillation transmission component 300.

[0040] Therefore, the MEMS gyroscope of the embodiment can amplify and display the stress change of the stress sensing area through the initial breakdown electric parameters and the breakdown electric parameter change values with large change amplitudes based on the piezoresistance-avalanche effect of the effect junction, so as to improve the sensing sensitivity of the gyroscope to the received angular velocity. Meanwhile, the correlation between the displacement of the oscillation transmission component 300, the angular velocity of the gyroscope, the Coriolis force, the driving voltage of the oscillation driving component 200, the stress of the stress sensing area, the initial breakdown electric parameters and the breakdown electric parameter change values is comprehensively considered, and the angular velocity is more accurately obtained, so as to greatly improve the angular velocity measurement sensitivity of the gyroscope. Meanwhile, the MEMS gyroscope only needs to set the simple effect junction in the stress sensing area of the connecting beam 400 and connect the reverse bias power supply, and then cooperate with the measuring component and the control component to perform high-precision angular velocity measurement, so as to have simple structure, small size, low manufacturing difficulty and low cost.

[0041] In the above description, the connecting beam 400 is arranged in the internal structure of the oscillation driving component 200, and the connecting beam 400 is also arranged between the oscillation transmission component 300 and the base 100. In addition to the above form, according to the structure of the oscillation transmission component 300, the connecting beam 400 can be arranged only in the internal structure of the oscillation transmission component 300, or the connecting beam 400 can be arranged only between the oscillation transmission component 300 and the base 100.

[0042] Specifically, the measuring assembly can include a lock-in amplifier to ensure its sensitivity and accuracy in measuring the breakdown electrical parameter of the effect junction, and accordingly ensure the sensitivity and accuracy of the gyroscope in measuring the angular velocity.

[0043] In the embodiment, in the step of calculating the angular velocity according to the breakdown electrical parameter, the structure-related parameter of the angular velocity sensing device, and the driving voltage of the oscillation driving assembly 200, the S406 control assembly can specifically include: calculating the stress of the corresponding connecting beam 400 according to the breakdown electrical parameter and the structure-related parameter of the angular velocity sensing device; calculating the displacement motion information of the oscillation transmission assembly 300 according to the stress and the structure-related parameter of the angular velocity sensing device; and calculating the angular velocity according to the displacement motion information, the structure-related parameter of the angular velocity sensing device, and the driving voltage of the oscillation driving assembly 200. When the structure of the angular velocity sensing device is determined, by setting the initial breakdown voltage applied to the effect junction by the reverse bias power supply and the frequency of the driving voltage applied to the oscillation transmission assembly 300 by the oscillation driving assembly 200, the stress of the connecting beam 400, the displacement motion information of the oscillation transmission assembly 300, and the Coriolis force received by the gyroscope can be sequentially obtained according to the breakdown electrical parameter measured by the detecting assembly and the structure-related parameter of the angular velocity sensing device, and finally the angular velocity received by the gyroscope can be obtained.

[0044] Optionally, in the embodiment, the reverse bias power supply can be a reverse bias voltage source with constant voltage, and a constant reverse voltage is applied to the effect junction by the reverse bias voltage source to make the effect junction enter a breakdown state. In use, the measuring assembly measures the breakdown current of the effect junction as the breakdown electrical parameter. In the step of calculating the stress of the corresponding connecting beam 400 according to the breakdown electrical parameter and the structure-related parameter of the angular velocity sensing device, the step includes:

[0045] The stress is calculated according to the following formula:

[0046]

[0047] In the formula, σ is the stress received by the stress sensing area, Pa; ΔI is the change value of the breakdown current of the effect junction when the stress sensing area receives stress, A; I0 is the initial breakdown current of the effect junction when the stress sensing area does not receive stress, A; α is a material parameter related to the band gap of the connecting beam, eV / Pa; q is the electronic charge constant, 1.602×10

[0048] VT Th = k B T / q.

[0049] In the formula, σ is the stress received by the stress sensing area, Pa; ΔI is the change value of the breakdown current of the effect junction when the stress sensing area receives stress, A; I0 is the initial breakdown current of the effect junction when the stress sensing area does not receive stress, A; α is a material parameter related to the band gap of the connecting beam, eV / Pa; q is the electronic charge constant, 1.602×10 -19 C; V Th is the thermal voltage, V; V BR0 is the constant reverse voltage, V; n is the error coefficient; k Bis Boltzmann's constant; T is the absolute temperature of the environment in which the connecting beam is located, in K.

[0050] Where σ is the stress to be determined; ΔI is the change value of the breakdown electrical parameter in the breakdown electrical parameters, and I0 is the initial breakdown electrical parameter; α, q, V Th V BR0 n, k B T represents the structural parameters of the angular velocity sensing device.

[0051] In addition to connecting a constant reverse bias voltage source to the junction to break it down, a constant reverse bias current source can also be connected across the junction. By applying a constant reverse current to the junction, the junction is brought into a breakdown state. In use, the measuring component measures the breakdown voltage of the junction as the breakdown electrical parameter. The step of calculating the stress of the corresponding connecting beam based on the breakdown electrical parameter and the structural parameters of the angular velocity sensing device includes:

[0052] The stress is calculated using the following formula:

[0053]

[0054] In the formula, σ is the stress in the stress-induced zone, in Pa; ΔV BR V represents the change in breakdown voltage of the stress-induced region junction under stress over time. BR0 α is the initial breakdown voltage of the stress-inducing region before stress aging, in V; α is the material parameter related to the connecting beam and the band gap, in eV / Pa; E g0 The initial band gap of the material used to connect the beams, eV; k B is Boltzmann's constant; T is the absolute temperature of the environment in which the connecting beam is located, in K.

[0055] Where σ is the stress to be determined; ΔV BR V represents the breakdown voltage change value in the breakdown electrical parameters. BR0 The initial breakdown voltage in the breakdown electrical parameters; α, E g0 k B T represents the structural parameters of the angular velocity sensing device.

[0056] Optionally, in this embodiment, there can be multiple connecting beams 400, which are distributed in a dispersed manner within the oscillation transmission component 300. In use, the breakdown electrical parameters of the junctions on the connecting beams 400 can be correlated with and characterize the displacement motion information of the oscillation transmission component 300. By setting multiple connecting beams 400 according to the structure of the oscillation transmission component 300, and by measuring and calculating the breakdown electrical parameters of the junctions on each connecting beam 400, more accurate displacement motion information can be obtained, thereby further improving the accuracy of the measured angular velocity.

[0057] Preferably, in the embodiment, the oscillation transmission assembly 300 is a symmetrical structure, and the plurality of connecting beams 400 are arranged symmetrically.

[0058] Specifically, in the embodiment, the effect junction can be a PN junction. During manufacturing, the PN junction in the form of a lightly doped junction can be obtained through a doping process at the connecting beam 400.

[0059] Of course, in other embodiments, the effect junction can also be a junction form having a piezoresistance-avalanche effect other than a PN junction, and is not limited to a PN junction.

[0060] In the embodiment, the connecting end region of the connecting beam 400 serves as a stress sensing area. Specifically, the base 100 is provided with an anchor area 500, one end of the connecting beam 400 away from the oscillation transmission assembly 300 is fixedly connected to the anchor area 500, and the connecting area of the connecting beam 400 and the anchor area 500 serves as a stress sensing area. When the gyroscope is subjected to the same angular velocity, the connecting area of the connecting beam 400 and the anchor area 500 has a larger change in the sensed stress, and the degree of firing of the piezoresistance-avalanche effect of the effect junction is larger. Accordingly, the change range of the breakdown electrical parameters of the effect junction is larger, and the amplification effect of the stress of the stress change area and the angular velocity is further improved, thereby further improving the measurement sensitivity of the gyroscope.

[0061] Of course, in other embodiments, the effect junction can also be arranged at any other area of the connecting beam 400 that can sense the stress change.

[0062] Optionally, in the embodiment, the base 100 is provided with an anchor area 500, one end of at least part of the connecting beam 400 is fixedly connected to the oscillation transmission assembly 300, and the other end is fixedly connected to the anchor area 500. The anchor area 500 is provided with a first electrode and a second electrode, the first electrode is connected to the first end of the effect junction, and the second electrode is connected to the second end of the effect junction. During use, the two power supply ends of the reverse bias power supply are connected to the first electrode and the second electrode one by one, and the two connecting ends of the measurement assembly are connected to the first electrode and the second electrode one by one. The effect junction has a small volume, and the first electrode and the second electrode have a fixed position and a large volume in the anchor area 500. During connection, the reverse bias power supply and the measurement assembly can be connected to the effect junction through the connection with the first electrode and the second electrode, thereby improving the connection convenience and stability, and accordingly improving the manufacturing convenience and use stability of the gyroscope.

[0063] Specifically, in the embodiment, as shown in FIG. 4, the first electrode and the second electrode are arranged on the anchor area 500. Figure 1As shown, the gyroscope can adopt a double-mass block form symmetrically arranged about the Y direction, and the oscillation transmission assembly 300 can include a driving frame 310, a Coriolis frame 320, and a detection frame 340, wherein the driving frame 310 includes two driving frame bodies 311 symmetrically arranged about the Y direction and each provided with an opening 312 on one side, and the two driving frame bodies 311 are connected by a connecting arm 313 between the first ends and the second ends in the Y direction, and the connecting arm 313 is rotationally connected to the base 100 at the symmetric position in the Y direction; the outer side frame strips of the two driving frame bodies 311 along the X direction are connected to the oscillation driving assembly 200, and the oscillation driving assembly 200 is used to drive the driving frame 310 to oscillate along the Y direction; the Coriolis frame 320 includes two Coriolis frame bodies 321, and the two Coriolis frame bodies 321 are located in the two driving frame bodies 311 one by one, and the Coriolis frame body 321 is connected by an X one-way spring 330 between the two ends in the X direction and the corresponding driving frame body 311; the detection frame 340 includes two detection frame bodies 341, and the two detection frame bodies 341 are located in the two Coriolis frame bodies 321 one by one, and the detection frame body 341 is connected by a Y one-way spring 350 between the two ends in the Y direction and the corresponding Coriolis frame body 321, and the two detection frame bodies 341 are connected by a coupling spring 342; wherein the two ends of the detection frame body 341 along the X direction are connected by a connecting beam 400 between the base 100, and the outer side frame strips of the driving frame body 311 along the Y direction are connected by the connecting beam 400 between the base 100.

[0064] Here is one of the specific forms of the oscillation transmission assembly 300 when the angular velocity sensing device is a double-mass block, wherein the driving frame 310, the Coriolis frame 320, and the detection frame 340 are connected to form the oscillation transmission assembly 300 through the coupling spring 342, the Y one-way spring 350, and the X one-way spring 330, and the two ends of the driving frame 310 in the Y direction are rotationally connected to the base 100 through the connecting arm 313, the outer side frame strips on the two sides in the Y direction are fixedly connected to the base 100 through the connecting beam 400, and the outer side frame strips on the two sides in the X direction of the detection frame 340 are fixedly connected to the base 100 through the connecting beam 400. The oscillation driving assembly 200 is two groups, and the two groups of oscillation driving assemblies 200 are connected one by one to the outer side frame strips on the two sides in the X direction of the driving frame 310, and are used to drive the corresponding driving frame body 311 to oscillate along the Y direction.

[0065] For the angular velocity sensing device of this form, in the step of calculating the displacement motion information of the oscillation transmission assembly 300 according to the structure-related parameters of the stress and angular velocity sensing device, the Y direction displacement of the driving frame 310 and the X direction displacement of the detection frame 340 are calculated according to the structure-related parameters of the stress and angular velocity sensing device, and the ratio of the Y direction displacement to the X direction displacement is taken as the displacement motion information.

[0066] Specifically, in use, the reverse bias power supply is used to apply a reverse voltage to the effect junction to make it break down, and the detection assembly feeds the detected breakdown electrical parameter of the effect junction to the control assembly as an initial breakdown electrical parameter; the oscillation driving assembly 200 is started and drives the driving frame 310 to perform a reciprocating oscillation movement along the Y direction, the connecting beam 400 connected between the driving frame 310 and the base 100 is deformed to generate stress, the breakdown electrical parameter of the effect junction changes greatly under the piezoresistance-avalanche effect, and the detection assembly feeds the measured breakdown electrical parameter change value to the control assembly, and the control assembly can calculate the stress of the corresponding connecting beam 400 according to the initial breakdown electrical parameter, the breakdown electrical parameter change value and the structure-related parameters of the angular velocity sensing device, and further calculate the Y direction displacement of the driving frame 310 according to the stress and the structure-related parameters of the angular velocity sensing device.

[0067] Since the X unidirectional spring 330 connected between the driving frame 310 and the Coriolis frame 320 has an elastic structure in the X direction and a rigid structure in the Y direction, the Coriolis frame 320 performs a synchronous oscillation movement along the Y direction with the driving frame 310 under the connection of the X unidirectional spring 330; when the gyroscope is subjected to an angular velocity around the Z direction, the Coriolis frame 320 will be subjected to a Coriolis force to generate a movement along the X direction, and the movement is transmitted to the detection frame 340 through the Y unidirectional spring 350; the connecting beam 400 connected between the detection frame 340 and the base 100 is deformed to generate stress, the breakdown electrical parameter of the effect junction changes greatly under the piezoresistance-avalanche effect, the detection assembly feeds the measured breakdown electrical parameter change value to the control assembly, and the control assembly can calculate the stress of the corresponding connecting beam 400 according to the initial breakdown electrical parameter, the breakdown electrical parameter change value and the structure-related parameters of the angular velocity sensing device, and further calculate the X direction displacement of the detection frame 340 according to the stress and the structure-related parameters of the angular velocity sensing device.

[0068] Then, the ratio of the Y direction displacement of the driving frame 310 to the X direction displacement of the detection frame 340 is taken as displacement movement information, and the angular velocity is calculated according to the displacement movement information, the structure-related parameters of the angular velocity sensing device and the driving voltage of the oscillation driving assembly 200.

[0069] Specifically, the angular velocity can be calculated according to the following formula:

[0070]

[0071] In the formula, Ω Z is the angular velocity of the angular velocity sensing device, rad / s; A s is the X direction displacement of the detection frame, m; A d is the Y direction displacement of the Coriolis frame, m; m d is the equivalent mass of the driving frame, kg; mc m is the equivalent mass of the drive frame, kg; m s f is the equivalent mass of the detection frame, kg; f s f is the modal frequency of the detection frame, Hz; f d f is the modal frequency of the drive frame, Hz; f in f is the frequency of the drive voltage, Hz; Q d Q is the quality factor associated with the drive frame and damping. s Q is the quality factor associated with the detection frame and damping.

[0072] Of course, in other embodiments, the angular velocity sensing device can also adopt other forms of dual mass, single mass, four mass, butterfly, ring structure, etc., and is not limited to the above-mentioned dual mass form.

[0073] As shown in Figure 2 , the angular velocity sensing device can also adopt a single mass form, and the oscillation driving assembly 200 is two groups, and the two groups of oscillation driving assemblies 200 are connected to the two ends of the oscillation transmission assembly 300Y in one-to-one correspondence. The two ends of the oscillation transmission assembly 300X are both fixedly connected to the base 100 through the connecting beam 400, wherein the stress sensing area of the connecting beam 400 is set to be effective.

[0074] Or as shown in Figure 3 , the angular velocity sensing device can also adopt a butterfly structure, wherein the oscillation driving assembly 200 is not shown, and the oscillation transmission assembly 300 includes two transmission units 360 and two connecting units 370, wherein a single connecting unit 370, a single transmission unit 360, a single transmission unit 360 and a single connecting unit 370 are sequentially and spaced arranged along the Y direction, and adjacent two are connected through the connecting beam 400. The two connecting units 370 are fixedly connected to the base 100 through the anchor area 500 at one end away from the connecting beam 400.

[0075] Wherein, the oscillation driving assembly 200 can adopt a comb capacitor, and the oscillation driving assembly 200 includes a matched fixed comb 210 and a movable comb 220, the fixed comb 210 is fixedly connected to the base 100, and the movable comb 220 is fixedly connected to the drive frame 310 of the oscillation transmission assembly 300; in use, the drive voltage between the fixed comb 210 and the movable comb 220 is changed, and the movable comb 220 is driven to reciprocating oscillation movement along the Y direction through the change of electrostatic force, thereby driving the drive frame 310 to oscillate along the Y direction. Of course, in other embodiments, the oscillation driving assembly 200 can also adopt other forms, which can drive the oscillation transmission assembly 300 to oscillate along the preset direction.

[0076] Finally, it should be noted that: the above embodiments are used to illustrate the technical solutions of the present application, but not limited to them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; 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 device for sensing angular velocity based on the piezoresistive-avalanche effect, characterized in that, The base (100), the oscillation driving assembly (200) arranged on the base (100) and the oscillation transmission assembly (300) connected between the base (100) and the oscillation driving assembly (200); the internal structure of the oscillation transmission assembly (300) has a connecting beam (400) and / or the connecting beam (400) is connected between the oscillation transmission assembly (300) and the base (100); The oscillation driving assembly (200) is used for driving the oscillation transmission assembly (300) to perform oscillation movement along a preset direction, the connecting beam (400) has a stress sensing area capable of sensing the oscillation movement, and the stress sensing area is provided with an effect junction having a piezoresistance-avalanche effect.

2. The angular rate sensing device of claim 1, wherein The connecting beam (400) is a plurality of connecting beams (400) which are dispersedly arranged on the oscillation transmission assembly (300).

3. The angular rate sensing device of claim 2, wherein, The oscillation transmission assembly (300) is a symmetrical structure, and the plurality of connecting beams (400) are symmetrically arranged.

4. The angular rate sensing device of claim 1, wherein, The effect junction is a PN junction.

5. The angular rate sensing device of claim 1, wherein, The connecting end region of the connecting beam (400) serves as the stress sensing area.

6. The angular rate sensing device of claim 1, wherein, The base (100) is provided with an anchor area (500), one end of at least part of the connecting beam (400) is fixedly connected to the oscillation transmission assembly (300), the other end is fixedly connected to the anchor area (500), the anchor area (500) is provided with a first electrode and a second electrode, the first electrode is connected to a first end of the effect junction, and the second electrode is connected to a second end of the effect junction.

7. The angular rate sensing device of claim 1, wherein The oscillation transmission assembly (300) comprises: The driving frame (310) comprises two driving frame bodies (311) which are symmetrically arranged about the Y direction and are provided with openings (312) on the opposite sides, and connecting arms (313) are connected between the first ends and the second ends of the two driving frame bodies (311) in the Y direction, and the connecting arms (313) are rotationally connected to the base (100) at the symmetrical positions in the Y direction; the outer side frame strips of the two driving frame bodies (311) in the X direction are connected to the oscillation driving assembly (200), and the oscillation driving assembly (200) is used for driving the driving frame bodies (311) to oscillate in the Y direction; The Coriolis frame (320) comprises two Coriolis frame bodies (321), the two Coriolis frame bodies (321) are one-to-one corresponding to the two driving frame bodies (311), and X one-way springs (330) are connected between the two ends of the Coriolis frame bodies (321) and the corresponding driving frame bodies (311) in the X direction; and The detection frame (340) comprises two detection frame bodies (341), the two detection frame bodies (341) are one-to-one corresponding to the two Coriolis frame bodies (321), Y one-way springs (350) are connected between the two ends of the detection frame bodies (341) and the corresponding Coriolis frame bodies (321) in the Y direction, and a coupling spring (342) is connected between the two detection frame bodies (341); The connecting beams (400) are connected between the detection frame body (341) and the base (100) at both ends of the detection frame body (341) along the X direction, and the connecting beams (400) are connected between the base (100) and the outer side frame strips of the driving frame body (311) along the Y direction.

8. A MEMS gyroscope, characterized by The angular velocity sensing device comprises a reverse bias power supply, a measuring assembly, a control assembly and the angular velocity sensing device of any one of claims 1-7, the reverse bias power supply is connected to both ends of the effect junction in the angular velocity sensing device, and is used for applying a reverse voltage to the effect junction to make it enter a breakdown state; the measuring assembly is connected to the effect junction, and is used for measuring a breakdown electrical parameter of the effect junction; and the control assembly is communicatively connected to the reverse bias power supply and the measuring assembly.

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