Anti-interference high-sensitivity integrated quartz resonance accelerometer chip structure

Abstract

An anti-interference high-sensitivity integrated quartz resonance accelerometer chip structure comprises a pendulum group platform, an upper pendulum assembly is connected above the pendulum group platform, and a lower pendulum assembly is connected below the pendulum group platform. The upper swing assembly and the lower swing assembly are completely the same in structural composition and are symmetrically arranged relative to the swing assembly platform. The upper pendulum assembly comprises a quartz resonator and a metal pendulum which are assembled and fixed through glue; the upper pendulum assembly and the lower pendulum assembly are assembled by adopting metal pendulum-quartz resonators through surface mounting and are aligned and assembled with a pendulum group platform to form a sandwich chip structure, the mass of an inertial mass block is doubled, and the sensitivity of the accelerometer is improved; an annular stress isolation groove and a double-C-shaped stress isolation groove are designed in the metal pendulum, so that the influence of complex interference factors such as assembling residual stress, external interference stress and interference thermal stress on the axial stress of the quartz resonator is reduced, temperature drift and time drift are inhibited, and long-term stability is improved.

Description

Technical Field

[0001] The invention relates to the technical field of resonant accelerometers, and in particular to an anti-interference high-sensitivity integrated quartz resonant accelerometer chip structure. Background Art

[0002] In the existing acceleration measurement field, traditional voltage output sensors generally face intrinsic technical bottlenecks, and their measurement accuracy is limited by the inherent amplitude stability defects and noise floor limitations of sensitive components. Resonant accelerometers, which form a significant technical difference with them, have gradually become the mainstream technical solution for high-precision inertial measurement in recent years. This type of sensor is based on the physical characteristics of micromechanical resonators. It converts the input acceleration into the offset of the characteristic frequency for signal characterization. This sensing mechanism based on frequency domain modulation reconstructs the measurement form at the physical level, decoupling the final output of the system from the signal amplitude. Its unique frequency domain signal characteristics fundamentally avoid the traditional voltage output sensor's stringent requirements for amplitude stability and noise suppression performance.

[0003] Single crystal silicon and single crystal piezoelectric quartz are the mainstream materials for the conversion components of resonant accelerometers. Single crystal silicon material has excellent mechanical strength and anisotropic cutting characteristics. Its standardized semiconductor processing technology can accurately control the geometric parameters of micromechanical structures, and it occupies a mainstream position in MEMS devices. However, its electrostatic comb drive architecture requires the construction of a complex drive detection coupling mechanism, which not only causes asymmetric distortion of the effective elastic coefficient of the resonant beam, but more importantly, the electrostatic excitation mechanism will cause second-order nonlinear displacement noise, and its amplitude is positively correlated with the supply voltage fluctuation, resulting in an increase in the background noise of the silicon-based resonator, which seriously restricts the dynamic range and long-term stability of the device. In comparison, single crystal piezoelectric quartz, relying on its natural piezoelectric effect formed by the orderly arrangement of the lattice, can achieve efficient electromechanical coupling through surface electrodes without external excitation components. Its thermoelastic damping confinement characteristics along the Z-axis direction give the device excellent frequency stability.

[0004] The existing integrated resonant accelerometer ([1] Bi Xiaowei, Ma Yuefei, Du Wei, et al. Development of a split quartz vibrating beam accelerometer [J]. Navigation and Control, 2019, 18(04): 77-82+101.) has a chip with a characteristic structure of a single mass pendulum and dual opposed quartz resonators. Since the inertial force provided by the mass pendulum is limited and the stiffness of the mass-spring system caused by the dual opposed quartz resonators increases, the sensitivity of the accelerometer is restricted. On the other hand, the integrated resonant accelerometer uses metal-quartz bonding to complete the mass-spring integration. When the temperature changes, the heterogeneous materials generate thermal stress, bonding residual stress and external interference stress, which reduces the temperature characteristics and anti-interference performance of the accelerometer, limiting the improvement of the long-term stability of the accelerometer. Summary of the invention

[0005] In order to overcome the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide an anti-interference and high-sensitivity integrated quartz resonator accelerometer chip structure, which improves the low sensitivity and stability of the resonator accelerometer.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] An anti-interference and high-sensitivity integrated quartz resonator accelerometer chip structure includes a pendulum group platform 2, an upper pendulum assembly 1 is connected above the pendulum group platform 2, and a lower pendulum assembly 3 is connected below the pendulum group platform 2; the upper pendulum assembly 1 and the lower pendulum assembly 3 have exactly the same structural composition, and the upper pendulum assembly 1 and the lower pendulum assembly 3 are symmetrically arranged with respect to the pendulum group platform 2.

[0008] The upper pendulum assembly 1 includes a quartz resonator 5 and a metal pendulum 6 fixed by glue assembly; the quartz resonator 5 includes a double-ended clamped tuning fork structure 5-2 and an upper fixing disk 5-1 and a lower fixing disk 5-3 connected to both ends thereof.

[0009] The metal pendulum 6 includes double "C" stress isolation grooves 6-1, annular stress isolation grooves 6-2, first quartz resonator auxiliary alignment grooves 6-3, vibration beam suspension grooves 6-4, hinges 6-5, first assembly alignment grooves 6-6, mass block isolation grooves 6-7, anchoring disks 6-8 and inertial mass blocks 6-9, second quartz resonator auxiliary alignment grooves 6-14;

[0010] The annular stress isolation groove 6-2 is symmetrically arranged with respect to the vertical symmetry axis 6-10 of the top view of the metal pendulum part structure, the center of the annular structure coincides with the center of the entire metal pendulum structure, and the annular stress isolation groove 6-2 is connected to the mass block isolation groove 6-7, so that the double "C" stress isolation grooves 6-1, hinges 6-5, and inertial mass blocks 6-9 are in a suspended state;

[0011] The two "C" - shaped isolation grooves of the double "C" stress isolation groove 6-1 are arranged in a buckled state, a first quartz resonator auxiliary alignment groove 6-3 is arranged on the inner groove of the double "C" stress isolation groove 6-1, vibration beam suspension grooves 6-4 are arranged inside and below the double "C" stress isolation groove 6-1, and vibration beam suspension grooves 6-4 are arranged on both the front and back of the metal pendulum 6;

[0012] The hinge 6-5 is symmetrically arranged with respect to the vertical symmetry axis 6-10 of the top view of the metal pendulum part structure, its cross-sectional shape partially coincides with the profile line 6-11 of the hinge structure of two identical circles, and is symmetric with respect to the vertical symmetry axis 6-12 and the horizontal symmetry axis 6-13 of the hinge structure profile. One end of the hinge 6-5 is connected to the lower part of the metal pendulum 6 of the double "C" stress isolation groove 6-1, and the other end is connected to the inertial mass block 6-9;

[0013] The inertial mass block 6-9 is symmetrical about the vertical symmetry axis 6-10 of the metal pendulum structure when viewed from above. A second quartz resonator auxiliary alignment groove 6-14 is arranged on the inertial mass block 6-9, which cooperates with the first quartz resonator auxiliary alignment groove 6-3 in the double "C" stress isolation groove 6-1 to complete the precise alignment and assembly of the quartz resonator 5 and the metal pendulum 6. The inertial mass block 6-9 is separated from the anchor plate 6-8 by the mass block isolation groove 6-7.

[0014] The anchor plate 6-8 is symmetrically arranged with respect to the vertical symmetry axis 6-10 when viewed from above the metal pendulum structure, and a first assembly alignment groove 6-6 for assembling the chip structure is arranged thereon. The first assembly alignment groove 6-6 is symmetrically arranged with respect to the vertical symmetry axis 6-10 when viewed from above the metal pendulum structure.

[0015] The upper and lower surfaces of the pendulum assembly platform 2 are symmetrical about the chip cross-sectional structural symmetry axis 4, and are both provided with an assembly limit groove 2-1, a circuit board mounting plane 2-2, a pendulum structure suspension groove 2-3, a second assembly alignment groove 2-4 and a metal pendulum mounting plane 2-5;

[0016] The metal pendulum mounting plane 2-5 is of the same shape as the anchoring plate 6-8 of the metal pendulum 6, and is symmetrically arranged about the top view structural symmetry axis 2-6 of the pendulum group platform;

[0017] The arrangement of the pendulum structure suspended slot 2-3 is such that after the upper pendulum assembly 1 and the pendulum group platform 2 are assembled, the inertial mass block 6-9, the annular stress isolation slot 6-2, the double "C" stress isolation slot 6-1 and the hinge 6-5 of the metal pendulum 6 are partially suspended, and the pendulum structure suspended slot 2-3 is symmetrically arranged about the top view structural symmetry axis 2-6 of the pendulum group platform;

[0018] After the upper pendulum assembly 1 is assembled with the pendulum group platform 2, the bottom surface of the suspended slot 2-3 of the pendulum structure and the lower plane of the inertial mass block 6-9 form an air cavity for squeeze film damping, and the squeeze film damping is set by adjusting the depth of the suspended slot 2-3 of the pendulum structure;

[0019] After the upper pendulum assembly 1 is assembled with the pendulum group platform 2, the height of the upper surface of the quartz resonator 5 is lower than the circuit board mounting plane 2-2.

[0020] The metal pendulum 6 and the pendulum assembly platform 2 are both manufactured by precision machining technology, wherein the hinge 6 - 5 is stamped to achieve the corresponding curvature and thickness processing.

[0021] The quartz resonator 5 is manufactured by a quartz MEMS wet etching process.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The quartz resonant accelerometer chip of the present invention includes an upper pendulum assembly 1, a pendulum platform 2, and a lower pendulum assembly 3. Both the upper pendulum assembly 1 and the lower pendulum assembly 3 are assembled by mounting a metal pendulum 6 - quartz resonator 5, and are aligned and assembled with the pendulum platform 2 to form a "sandwich" chip structure. The mass of the inertial mass block 6 - 9 is doubled, effectively improving the sensitivity of the accelerometer. A circular stress isolation groove 6 - 2 and a double "C" stress isolation groove 6 - 1 are designed in the metal pendulum 6, reducing the influence of complex interference factors such as assembly residual stress, external interference stress, and interference thermal stress on the axial stress of the quartz resonator 5, suppressing temperature drift and time drift, and improving long-term stability. Description of the Drawings

[0024] Figure 1 It is the front view of the embodiment of the present invention.

[0025] Figure 2 It is the sectional view of the embodiment of the present invention.

[0026] Figure 3 It is the front view of the upper pendulum assembly of the embodiment of the present invention.

[0027] Figure 4 It is the top view of the quartz resonator of the embodiment of the present invention.

[0028] Figure 5 It is the top view of the metal pendulum of the embodiment of the present invention.

[0029] Figure 6 It is the sectional view of the metal pendulum of the embodiment of the present invention.

[0030] Figure 7 It is the top view of the pendulum platform of the embodiment of the present invention.

[0031] Figure 8 It is the sectional view of the pendulum platform of the embodiment of the present invention.

[0032] Figure 9 It is the front view of the pendulum platform of the embodiment of the present invention.

[0033] In the figure: 1 - upper swing component; 2 - swing group platform, 2-1 - assembly limit groove, 2-2 - circuit board mounting plane, 2-3 - swing structure suspension groove, 2-4 - second assembly alignment groove, 2-5 - metal swing mounting plane, 2-6 - axis of symmetry of the top view structure of the swing group platform; 3 - lower swing component; 4 - axis of symmetry of the chip cross-section structure; 5 - quartz resonator, 5-1 - upper fixing plate, 5-2 - double-ended clamped tuning fork structure, 5-3 - lower fixing plate; 6 - metal swing, 6-1 - double "C" stress isolation groove, 6-2 - annular stress isolation groove, 6-3 - first quartz resonator auxiliary alignment groove, 6-4 - vibration beam suspension groove, 6-5 - hinge, 6-6 - first assembly alignment groove, 6-7 - mass block isolation groove, 6-8 - anchoring plate, 6-9 - inertial mass block, 6-10 - vertical axis of symmetry of the top view of the partial structure of the metal swing, 6-11 - cross-sectional profile line of the hinge structure, 6-12 - vertical axis of symmetry of the cross-section of the hinge structure, 6-13 - horizontal axis of symmetry of the cross-section of the hinge structure, 6-14 - second quartz resonator auxiliary alignment groove. Detailed implementation mode

[0034] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments and the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0035] Refer to Figure 1 、 Figure 2 A high anti-interference and high-sensitivity integrated quartz resonator accelerometer chip structure, comprising a swing group platform 2, an upper swing component 1 is connected above the swing group platform 2, and a lower swing component 3 is connected below the swing group platform 2; the upper swing component 1 and the lower swing component 3 have exactly the same structural composition, and the upper swing component 1 and the lower swing component 3 are symmetrically arranged about the axis of symmetry 4 of the chip cross-section structure of the swing group platform 2;

[0036] Refer to Figure 3 The upper swing component 1 includes a quartz resonator 5 and a metal swing 6 fixedly assembled by glue; refer to Figure 4 The quartz resonator 5 includes a double-ended clamped tuning fork structure 5-2 and upper and lower fixing plates 5-1 and 5-3 connected to both ends thereof. Metal pads are arranged on the upper fixing plate 5-1 for connecting to an external circuit; electrodes are arranged on the double-ended clamped tuning fork structure 5-2, which are divided into three sections along the length direction of the tuning fork structure, and electrodes are arranged on the four side surfaces of the tuning fork structure for exciting the vibration of the quartz resonator; the lower fixing plate 5-3 has the same size as the upper fixing plate 5-1, is used to cooperate with the second quartz resonator auxiliary alignment groove 6-14, and is connected to the inertial mass block 6-9;

[0037] Refer to Figure 5 、Figure 6 The metal pendulum 6 includes a double "C" stress isolation groove 6-1, an annular stress isolation groove 6-2, a first quartz resonator auxiliary alignment groove 6-3, a vibration beam suspension groove 6-4, a hinge 6-5, a first assembly alignment groove 6-6, a mass block isolation groove 6-7, an anchor plate 6-8, an inertial mass block 6-9 and a second quartz resonator auxiliary alignment groove 6-14;

[0038] Reference Figure 5 The two "C"-shaped grooves of the double "C" stress isolation groove 6-1 are arranged in an interlocking state, and a first quartz resonator auxiliary alignment groove 6-3 is arranged on the inner groove of the double "C" stress isolation groove 6-1. A vibration beam suspension groove 6-4 is arranged inside and at the bottom of the double "C" stress isolation groove 6-1, and a vibration beam suspension groove 6-4 is arranged on the front and back of the metal pendulum 6; the annular stress isolation groove 6-2 and the double "C" stress isolation groove 6-1 are used to isolate thermal stress, assembly residual stress and external interference stress. By setting these two isolation grooves, the disturbance of complex interference stress to the quartz resonator can be greatly reduced, and the long-term stability of the accelerometer can be improved;

[0039] Reference Figure 5 The hinge 6-5 is symmetrically arranged about the vertical symmetry axis 6-10 when viewed from above the metal pendulum structure. Figure 6 , its cross-sectional shape partially overlaps with the hinge structure cross-sectional contour lines 6-11 of two identical circles, and is symmetrical about the hinge structure cross-sectional vertical symmetry axis 6-12 and the hinge structure cross-sectional horizontal symmetry axis 6-13. One end of the hinge 6-5 is connected to the metal pendulum 6 at the lower part of the double "C" stress isolation groove 6-1, and the other end is connected to the inertial mass block 6-9; the inertial mass block 6-9 is used to sense inertial acceleration, and the hinge 6-5 supports the inertial mass block 6-9. A quartz resonator 5 is arranged in the length direction of the hinge 6-5. One end of the quartz resonator 5 is located inside the double "C" stress isolation groove 6-1, and the other end is located on the surface of the inertial mass block 6-9 close to one side of the hinge 6-5. When acceleration is applied to the inertial mass block 6-9, the inertial mass block 6-9 will swing around the hinge 6-5 at a micro-angle, causing the quartz resonator 5 to generate stress in the axial direction, resulting in a shift in its natural frequency;

[0040] Reference Figure 5 The inertial mass block 6-9 is symmetrical about the vertical symmetry axis 6-10 when viewed from above the structure of the metal pendulum. A second quartz resonator auxiliary alignment groove 6-14 is arranged on the inertial mass block 6-9, which cooperates with the first quartz resonator auxiliary alignment groove 6-3 in the double "C" stress isolation groove 6-1 to complete the precise alignment and assembly of the quartz resonator 5 and the metal pendulum 6. The inertial mass block 6-9 is separated from the anchor plate 6-8 by the mass block isolation groove 6-7;

[0041] Reference Figure 5, the described anchoring disc 6-8 is symmetrically arranged with respect to the vertical symmetry axis 6-10 of the metal pendulum part structure. A first assembly alignment groove 6-6 for chip structure assembly is arranged thereon, and the first assembly alignment groove 6-6 is symmetrically arranged with respect to the vertical symmetry axis 6-10 of the metal pendulum part structure.

[0042] The quartz resonant accelerometer is essentially a force-sensitive sensor. Complex interference stresses have a great impact on the accurate and stable identification of the actual acceleration signal by the quartz resonator 5. The complex interference stresses are divided into external environmental interference stresses, assembly residual stresses, and thermal stresses between heterogeneous materials caused by the mismatch of the internal material thermal expansion coefficients. The annular stress isolation grooves 6-2 are symmetrically arranged, which can expand the path for the transfer of external interference stresses and assembly residual stresses from the anchoring disc 6-8 to the quartz resonator 5, reducing the influence of interference stresses; the double "C" stress isolation grooves 6-1 are axially symmetrically arranged. The double "C" stress isolation grooves 6-1 further increase the path for the transfer of external environmental interference stresses and assembly residual stresses to the quartz resonator 5. More importantly, the opening of the isolation grooves reduces the y-direction stiffness of the structure of the metal pendulum 6 near this position, having the function of a spring, and has an obvious inhibitory effect on the thermal stresses between heterogeneous materials and the residual stresses generated during the assembly of the quartz resonator 5 and the metal pendulum 6, further reducing the influence of complex interference stresses. The setting of the two isolation groove parts effectively reduces the interference of complex interference stresses on the axial stress of the quartz resonator 5, greatly improving the long-term stability of the accelerometer.

[0043] Refer to Figure 7 , Figure 8 , Figure 9 , the upper and lower surfaces of the described pendulum group platform 2 are symmetric with respect to the chip cross-section structure symmetry axis 4, and the assembly of the upper pendulum assembly 1 and the pendulum group platform 2 can be completed; and both are provided with assembly limit grooves 2-1, circuit board mounting planes 2-2, pendulum structure suspension grooves 2-3, second assembly alignment grooves 2-4, and metal pendulum mounting planes 2-5;

[0044] Refer to Figure 7 , the described metal pendulum mounting plane 2-5 has the same shape as the anchoring disc 6-8 of the metal pendulum 6 and is symmetrically arranged with respect to the symmetry axis 2-6 of the pendulum group platform top view structure;

[0045] Refer to Figure 7 , the setting of the described pendulum structure suspension groove 2-3, after the upper pendulum assembly 1 and the pendulum group platform 2 are assembled, suspends the inertial mass block 6-9, annular stress isolation groove 6-2, double "C" stress isolation groove 6-1, and hinge 6-5 parts of the metal pendulum 6. The pendulum structure suspension groove 2-3 is symmetrically arranged with respect to the symmetry axis 2-6 of the pendulum group platform top view structure;

[0046] Refer to Figure 1, after the upper pendulum assembly 1 and the pendulum assembly platform 2 are assembled, an air cavity for squeeze film damping is formed between the bottom surface of the pendulum structure suspension groove 2-3 and the lower plane of the inertial mass block 6-9. The squeeze film damping is set by adjusting the depth of the pendulum structure suspension groove 2-3;

[0047] Refer to Figure 1 , after the upper pendulum assembly 1 and the pendulum assembly platform 2 are assembled, the height of the upper surface of the quartz resonator 5 is lower than the circuit board mounting plane 2-2.

[0048] Refer to Figure 1 , Figure 2 , a second assembly alignment groove 2-4 is provided on the metal pendulum mounting plane 2-5, which is in the same relative position as the first assembly alignment groove 6-6 provided on the anchoring disk 6-8 of the metal pendulum 6. During assembly, the anchoring disk 6-8 on the side of the metal pendulum 6 without the quartz resonator 5 is installed on the metal pendulum mounting plane 2-5. At the assembly alignment groove, a pin can be used to complete the precise alignment and assembly of the pendulum assembly and the pendulum assembly platform 2. After assembly, part of the metal pendulum structure including the double "C" stress isolation groove 6-1, the hinge 6-5, and the inertial mass block 6-9 is suspended by using the pendulum structure suspension groove 2-3 opened on the pendulum assembly platform 2, and the upper surface of the quartz resonator 5 is lower than the circuit board mounting plane 2-2. The two pendulum assemblies are symmetrically installed by using the metal pendulum mounting plane 2-5 and the assembly alignment groove of the pendulum assembly platform 2.

[0049] The metal pendulum 6 and the pendulum assembly platform 2 are both manufactured by precision machining processes, and the hinge 6-5 is processed to have the corresponding radian and thickness by stamping.

[0050] The quartz resonator 5 is fabricated by quartz MEMS wet etching process.

[0051] Sensitivity is used to evaluate the ability of an accelerometer to convert an acceleration signal into a measurement signal. The output of the quartz resonant accelerometer of the present invention is a frequency signal. Therefore, the unit of sensitivity is Hz / g, which is defined as the frequency value output under the action of a unit gravitational acceleration g. To improve the sensitivity of the accelerometer, the present invention proposes an integrated packaging structure with two inertial mass blocks and a quartz resonator 5 bonded on one side. The upper pendulum assembly 1 and the lower pendulum assembly 3 provide two inertial mass blocks for the sensor to sense acceleration. A quartz resonator 5 is attached to one side of each pendulum assembly, which is used to convert the acceleration signal sensed by the inertial mass blocks 6-9 into an axial force signal of the quartz resonator 5, and then into a frequency change signal of the quartz resonator 5. The two pendulum assemblies are symmetric about the axis. When the same acceleration signal is input, the frequency of the quartz resonator 5 of one pendulum assembly increases, and the frequency of the quartz resonator 5 of the other pendulum assembly decreases. The two form a differential measurement, doubling the output compared to that of a single pendulum assembly. Therefore, the sensitivity of the accelerometer is doubled. In addition, during the design process, adjusting the dimensions of the inertial mass blocks 6-9 along the length direction of the quartz resonator can further improve the sensitivity.

[0052] The chip structure of the anti-interference high-sensitivity integrated quartz resonant accelerometer of the present invention can suppress complex interference stresses from the metal pendulum 6, ensuring that the quartz resonator 5 is protected from external and internal interference and improving the long-term stability performance of the accelerometer. At the same time, the double-inertial-mass-block structure of the upper pendulum assembly 1 and the lower pendulum assembly 3 symmetrically arranged in the present invention to achieve differential measurement of acceleration signals can effectively improve the sensitivity of the sensor, and finally realize the design and manufacture of a high-sensitivity quartz resonant accelerometer chip with anti-external interference and good long-term stability. The specific advantages are as follows:

[0053] (1) The setting of the annular stress isolation groove 6-2 can expand the path for external interference stresses and assembly residual stresses to transfer from the anchoring disk 6-8 to the quartz resonator 5, reducing the influence of interference stresses;

[0054] (2) The setting of the double "C" stress isolation groove 6-1 further increases the path for external environmental interference stresses and assembly residual stresses to transfer to the quartz resonator, and has an obvious inhibitory effect on the thermal stress between heterogeneous materials and the residual stress generated during the assembly of the quartz resonator 5 and the metal pendulum 6, further reducing the influence of complex interference stresses;

[0055] (3) The differential layout of the single-sided mounting of the quartz resonator 5 on the metal pendulum 6 and the symmetric mounting structure of the pendulum assemblies can double the sensitivity of the accelerometer.

Claims

1. An anti-interference high-sensitivity integrated quartz resonant accelerometer chip structure, including a pendulum group platform (2), characterized in that: The upper part of the swing group platform (2) is connected to the upper swing component (1), and the lower part of the swing group platform (2) is connected to the lower swing component (3); the upper swing component (1) and the lower swing component (3) have completely the same structural composition, and the upper swing component (1) and the lower swing component (3) are symmetrically arranged with respect to the swing group platform (2).

2. The structure according to claim 1, wherein: The upper pendulum assembly (1) comprises a quartz resonator (5) and a metal pendulum (6) assembled by glue; the quartz resonator (5) comprises a double-end fixed tuning fork structure (5-2) and an upper fixed plate (5-1) and a lower fixed plate (5-3) connected at both ends thereof.

3. The structure according to claim 2, characterized in that: The metal pendulum (6) comprises a double "C" stress isolation groove (6-1), an annular stress isolation groove (6-2), a first quartz resonator auxiliary alignment groove (6-3), a vibration beam suspension groove (6-4), a hinge (6-5), a first assembly alignment groove (6-6), a mass block isolation groove (6-7), an anchor plate (6-8), an inertial mass block (6-9) and a second quartz resonator auxiliary alignment groove (6-14); The annular stress isolation groove (6-2) is symmetrically arranged about the vertical symmetry axis (6-10) of the metal pendulum structure when viewed from above, the center of the annular structure coincides with the center of the entire metal pendulum structure, and the annular stress isolation groove (6-2) is connected to the mass block isolation groove (6-7), so that the double "C" stress isolation groove (6-1), the hinge (6-5), and the inertial mass block (6-9) are in a suspended state; The two "C"-shaped isolation grooves of the double "C" stress isolation groove (6-1) are arranged in an interlocking state, a first quartz resonator auxiliary alignment groove (6-3) is arranged on the inner groove of the double "C" stress isolation groove (6-1), a vibration beam suspension groove (6-4) is arranged inside and below the double "C" stress isolation groove (6-1), and a vibration beam suspension groove (6-4) is arranged on the front and back sides of the metal pendulum (6); The hinge (6-5) is symmetrically arranged about the vertical symmetry axis (6-10) of the metal pendulum structure when viewed from above, and its cross-sectional shape partially overlaps with the cross-sectional contour lines (6-11) of the hinge structure of two identical circles, and is symmetrical about the vertical symmetry axis (6-12) of the hinge structure cross-sectional and the horizontal symmetry axis (6-13) of the hinge structure cross-sectional. One end of the hinge (6-5) is connected to the lower part of the metal pendulum (6) of the double "C" stress isolation groove (6-1), and the other end is connected to the inertial mass block (6-9); The inertial mass block (6-9) is symmetrical about the vertical symmetry axis (6-10) of the metal pendulum structure when viewed from above. A second quartz resonator auxiliary alignment groove (6-14) is arranged on the inertial mass block (6-9) to cooperate with the first quartz resonator auxiliary alignment groove (6-3) in the double "C" stress isolation groove (6-1) to complete the precise alignment and assembly of the quartz resonator (5) and the metal pendulum (6). The inertial mass block (6-9) and the anchor plate (6-8) are separated by the mass block isolation groove (6-7); The described anchoring plate (6-8) is symmetrically arranged with respect to the vertical symmetry axis (6-10) of the metal pendulum part structure. A first assembly alignment groove (6-6) for chip structure assembly is arranged thereon, and the first assembly alignment groove (6-6) is symmetrically arranged with respect to the vertical symmetry axis (6-10) of the metal pendulum part structure.

4. The structure according to claim 3, characterized in that: The upper and lower surfaces of the described pendulum group platform (2) are symmetric with respect to the symmetry axis (4) of the chip cross-sectional structure, and both are provided with assembly limit grooves (2-1), circuit board mounting planes (2-2), pendulum structure suspension grooves (2-3), second assembly alignment grooves (2-4), and metal pendulum mounting planes (2-5); The described metal pendulum mounting plane (2-5) has the same shape as the anchoring plate (6-8) of the metal pendulum (6) and is symmetrically arranged with respect to the symmetry axis (2-6) of the pendulum group platform top view structure; After the upper pendulum assembly (1) is assembled with the pendulum group platform (2), the provided pendulum structure suspension groove (2-3) suspends the inertial mass block (6-9), annular stress isolation groove (6-2), double "C" stress isolation groove (6-1), and hinge (6-5) parts of the metal pendulum (6). The pendulum structure suspension groove (2-3) is symmetrically arranged with respect to the symmetry axis (2-6) of the pendulum group platform top view structure; After the upper pendulum assembly (1) is assembled with the pendulum group platform (2), the bottom surface of the pendulum structure suspension groove (2-3) and the lower plane of the inertial mass block (6-9) form an air cavity for squeeze film damping, and the squeeze film damping is set by adjusting the depth of the pendulum structure suspension groove (2-3); After the upper pendulum assembly (1) is assembled with the pendulum group platform (2), the height of the upper surface of the quartz resonator (5) is lower than the circuit board mounting plane (2-2).

5. The structure according to claim 3, characterized in that: The described metal pendulum (6) and pendulum group platform (2) are both manufactured by precision machining processes, and the hinge (6-5) is processed with the corresponding radian and thickness by stamping.

6. The structure according to claim 2, wherein: The described quartz resonator (5) is fabricated by quartz MEMS wet etching process.

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