Anti-interference and high-sensitivity integrated quartz resonant accelerometer chip structure

Abstract

An anti-interference, high-sensitivity integrated quartz resonant accelerometer chip structure comprises a pendulum platform, an upper pendulum assembly connected above the pendulum platform, and a lower pendulum assembly connected below the pendulum platform; the upper pendulum assembly and the lower pendulum assembly are identical in structure and symmetrically arranged about the pendulum platform; the upper pendulum assembly comprises a quartz resonator and a metal pendulum fixed by glue; the upper pendulum assembly and the lower pendulum assembly of the present invention are both assembled by mounting the metal pendulum-quartz resonator, and are aligned and assembled with the pendulum platform to form a "sandwich" chip structure, doubling the mass of the inertial mass block and improving the sensitivity of the accelerometer; an annular stress isolation groove and a double "C" stress isolation groove are designed in the metal pendulum to reduce 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, suppress temperature drift and time drift, and improve long-term stability.

Description

Technical Field

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

[0002] In the current field of acceleration measurement, traditional voltage-output sensors generally face inherent technical bottlenecks, their measurement accuracy constrained by the inherent amplitude stability flaws and noise floor limitations of their sensitive components. Resonant accelerometers, a significant technological departure from these sensors, have in recent years become the mainstream technology for high-precision inertial measurement. Based on the innovative physical properties of micromechanical resonators, these sensors convert input acceleration into characteristic frequency offsets for signal characterization. This frequency-domain modulation-based sensing mechanism physically reconstructs the measurement format, decoupling the system's final output from the signal amplitude. Their unique frequency-domain signal characteristics fundamentally circumvent the demanding amplitude stability and noise suppression requirements of traditional voltage-output sensors.

[0003] Single-crystal silicon and single-crystal piezoelectric quartz are the mainstream materials for the conversion components of current resonant accelerometers. Single-crystal silicon possesses excellent mechanical strength and anisotropic cutting properties. Its standardized semiconductor processing technology enables precise control of the geometric parameters of micromechanical structures, making it a dominant material 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 induces second-order nonlinear displacement noise, whose amplitude is positively correlated with supply voltage fluctuations. This increases the noise floor of the silicon-based resonator and severely constrains the dynamic range and long-term stability of the device. In comparison, single-crystal piezoelectric quartz, due to its natural piezoelectric effect formed by the orderly arrangement of the crystal lattice, achieves efficient electromechanical coupling through surface electrodes without the need for external excitation components. Its thermoelastic damping confinement along the Z-axis further endows the device with 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 improvement 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 causes the temperature characteristics and anti-interference performance of the accelerometer to decrease, limiting the improvement of the long-term stability performance of the accelerometer. Summary of the Invention

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

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

[0007] An anti-interference, high-sensitivity integrated quartz resonant accelerometer chip structure includes a pendulum group platform 2, an upper pendulum component 1 is connected above the pendulum group platform 2, and a lower pendulum component 3 is connected below the pendulum group platform 2; the upper pendulum component 1 and the lower pendulum component 3 have exactly the same structural composition, and are symmetrically arranged about 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 fixed tuning fork structure 5-2 and an upper fixed plate 5-1 and a lower fixed plate 5-3 connected at both ends.

[0009] 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 and an inertial mass block 6-9, and a second quartz resonator auxiliary alignment groove 6-14;

[0010] 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. 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 suspended.

[0011] The two C-shaped isolation grooves of the double C-shaped stress isolation groove 6-1 are arranged in an interlocking state. A first quartz resonator auxiliary alignment groove 6-3 is provided on the inner groove of the double C-shaped stress isolation groove 6-1. A vibration beam suspension groove 6-4 is arranged inside and below the double C-shaped stress isolation groove 6-1. Vibration beam suspension grooves 6-4 are provided on the front and back of the metal pendulum 6.

[0012] The hinge 6-5 is symmetrically arranged about the vertical symmetry axis 6-10 of the metal pendulum structure when viewed from above. Its cross-sectional shape partially coincides with the cross-sectional outline 6-11 of the hinge structure of two identical circles, and is symmetrical about the vertical symmetry axis 6-12 and the horizontal symmetry axis 6-13 of the hinge structure cross-sectional shape. 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 achieve 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 about the vertical symmetry axis 6-10 when looking down on the metal pendulum structure, and a first assembly alignment groove 6-6 for assembling the chip structure is arranged on it. The first assembly alignment groove 6-6 is symmetrically arranged about the vertical symmetry axis 6-10 when looking down on 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 and the anchoring plate 6-8 of the metal pendulum 6 have the same shape and are 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 pendulum structure suspended groove 2-3 and the lower plane of the inertial mass block 6-9 form an air cavity for squeeze film damping. The squeeze film damping is set by adjusting the depth of the pendulum structure suspended groove 2-3.

[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 processed by stamping to achieve the corresponding curvature and thickness.

[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 comprises an upper pendulum assembly 1, a pendulum platform 2, and a lower pendulum assembly 3. Both upper and lower pendulum assemblies 1 and 3 are assembled using a metal pendulum 6 and a quartz resonator 5 through surface-mount mounting. These components are aligned with the pendulum platform 2, forming a "sandwich" chip structure. The mass of the inertial mass block 6-9 is doubled, effectively improving the accelerometer's sensitivity. An annular stress isolation groove 6-2 and a double "C" stress isolation groove 6-1 are designed into the metal pendulum 6. These grooves reduce the effects of complex interference factors such as assembly residual stress, external interference stress, and thermal interference stress on the axial stress of the quartz resonator 5, suppressing temperature and time drift and improving long-term stability. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0025] Figure 2 2 is a cross-sectional view of an embodiment of the present invention.

[0026] Figure 3 This is the front view of the upper swing assembly according to an embodiment of the present invention.

[0027] Figure 4 This is a top view of a quartz resonator according to an embodiment of the present invention.

[0028] Figure 5 This is a top view of a metal pendulum according to an embodiment of the present invention.

[0029] Figure 6 This is a cross-sectional view of a metal pendulum according to an embodiment of the present invention.

[0030] Figure 7 This is a top view of the pendulum assembly platform according to an embodiment of the present invention.

[0031] Figure 8 This is a cross-sectional view of the pendulum assembly platform according to an embodiment of the present invention.

[0032] Figure 9 This is the front view of the pendulum platform according to an embodiment of the present invention.

[0033] In the figure: 1-upper pendulum assembly, 2-pendulum group platform, 2-1-assembly limit slot, 2-2-circuit board mounting plane, 2-3-pendulum structure suspension slot, 2-4-second assembly alignment slot, 2-5-metal pendulum mounting plane, 2-6-pendulum group platform top view structure symmetry axis, 3-lower pendulum assembly, 4, chip cross-section structure symmetry axis, 5-quartz resonator, 5-1-upper fixed plate, 5-2-double-end fixed tuning fork structure, 5-3-lower fixed plate, 6-metal pendulum, 6-1-double "C" stress isolation slot, 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-anchor plate, 6-9-inertial mass block, 6-10-vertical symmetry axis of the metal pendulum structure when viewed from above, 6-11-profile outline of the hinge structure, 6-12-vertical symmetry axis of the hinge structure section, 6-13-transverse symmetry axis of the hinge structure section, 6-14-second quartz resonator auxiliary alignment groove. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments and drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0035] Reference Figure 1 、 Figure 2 An anti-interference, high-sensitivity integrated quartz resonant accelerometer chip structure includes a pendulum platform 2, an upper pendulum assembly 1 connected above the pendulum platform 2, and a lower pendulum assembly 3 connected below the pendulum platform 2; the upper pendulum assembly 1 and the lower pendulum assembly 3 are identical in structure, and are symmetrically arranged about an axis of symmetry 4 of the chip cross-section structure of the pendulum platform 2;

[0036] Reference Figure 3 The upper pendulum assembly 1 includes a quartz resonator 5 and a metal pendulum 6 fixed by glue assembly; Figure 4 The quartz resonator 5 includes a double-ended 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. The upper fixed plate 5-1 is provided with a metal pad for connecting to an external circuit; the double-ended fixed tuning fork structure 5-2 is provided with electrodes, which are divided into three sections along the length direction of the tuning fork structure, and electrodes are provided on the four sides of the tuning fork structure for exciting the vibration of the quartz resonator; the lower fixed plate 5-3 is the same size as the upper fixed plate 5-1, is used to cooperate with the auxiliary alignment groove 6-14 of the second quartz resonator, and is connected to the inertial mass block 6-9;

[0037] Reference 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. A first quartz resonator auxiliary alignment groove 6-3 is provided 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. Vibration beam suspension grooves 6-4 are provided 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 providing these two isolation grooves, the disturbance of complex interference stress on the quartz resonator can be greatly reduced, thereby improving the long-term stability of the accelerometer;

[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 coincides with the cross-sectional contour lines 6-11 of the hinge structure of the two identical circles, and is symmetrical about the vertical symmetry axis 6-12 and the horizontal symmetry axis 6-13 of the hinge structure cross-sectional view. 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 provided 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 the hinge 6-5. When acceleration is applied to the inertial mass block 6-9, the inertial mass block 6-9 will swing at a micro-angle around the hinge 6-5, causing axial stress in the quartz resonator 5, 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 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 and the anchor plate 6-8 are separated by the mass block isolation groove 6-7.

[0041] Reference Figure 5The 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 on it. 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.

[0042] A quartz resonant accelerometer is essentially a force-sensitive sensor. Complex interference stresses significantly impact the quartz resonator 5's ability to accurately and stably detect actual acceleration signals. These complex interference stresses are classified into external environmental interference stress, assembly residual stress, and inter-material thermal stress caused by mismatched thermal expansion coefficients within the internal materials. The symmetrical arrangement of the annular stress isolation grooves 6-2 expands the transmission path for external interference stress and assembly residual stress from the anchor plate 6-8 to the quartz resonator 5, reducing the impact of these stresses. The axially symmetrical arrangement of the double "C" stress isolation grooves 6-1 further increases the transmission path for external environmental interference stress and assembly residual stress to reach the quartz resonator 5. More importantly, the presence of the isolation grooves reduces the y-direction stiffness of the metal pendulum 6 near this location, acting as a spring. This significantly suppresses inter-material thermal stress and residual stress generated during assembly between the quartz resonator 5 and the metal pendulum 6, further reducing the impact of these complex interference stresses. The provision of two isolation grooves effectively reduces the impact of these complex interference stresses on the axial stress of the quartz resonator 5, significantly improving the long-term stability of the accelerometer.

[0043] Reference Figure 7 、 Figure 8 、 Figure 9 The upper and lower surfaces of the pendulum assembly platform 2 are symmetrical about the chip cross-sectional structural symmetry axis 4, which can complete the assembly of the upper pendulum assembly 1 and the pendulum assembly platform 2; 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;

[0044] Reference Figure 7 The 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 about the symmetry axis 2-6 of the top view structure of the pendulum group platform;

[0045] Reference Figure 7 After the upper pendulum assembly 1 and the pendulum group platform 2 are assembled, the inertial mass block 6-9, the annular stress isolation groove 6-2, the double "C" stress isolation groove 6-1 and the hinge 6-5 of the metal pendulum 6 are suspended. The pendulum structure suspension groove 2-3 is symmetrically arranged about the top view structural symmetry axis 2-6 of the pendulum group platform.

[0046] Reference Figure 1After the upper pendulum assembly 1 is assembled with the pendulum group platform 2, the bottom surface of the pendulum structure suspended groove 2-3 and the lower plane of the inertial mass block 6-9 form an air cavity for squeeze film damping. The squeeze film damping is set by adjusting the depth of the pendulum structure suspended groove 2-3.

[0047] Reference Figure 1 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.

[0048] Reference Figure 1 、 Figure 2 A second assembly alignment groove 2-4 is provided on the metal pendulum mounting surface 2-5, which is aligned relative to the first assembly alignment groove 6-6 provided on the anchor plate 6-8 of the metal pendulum 6. During assembly, the anchor plate 6-8 on the side of the metal pendulum 6 without the quartz resonator 5 is mounted on the metal pendulum mounting surface 2-5. Pins can be used at the assembly alignment groove to precisely align the pendulum assembly with the pendulum platform 2. After assembly, the partial metal pendulum structure, including the double "C" stress isolation groove 6-1, hinge 6-5, and inertial mass block 6-9, is suspended using the pendulum structure suspension groove 2-3 provided on the pendulum platform 2, and the upper surface of the quartz resonator 5 is lower than the circuit board mounting surface 2-2. The two pendulum assemblies are symmetrically mounted using the metal pendulum mounting surface 2-5 and the assembly alignment groove of the pendulum platform 2.

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

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

[0051] Sensitivity evaluates an accelerometer's ability to convert acceleration signals into measurement signals. The output of the quartz resonant accelerometer of the present invention is a frequency signal, so the unit of sensitivity is Hz / g, defined as the frequency value output under unit gravitational acceleration (g). To improve the sensitivity of the accelerometer, the present invention proposes an integrated packaging structure with dual inertial masses and a quartz resonator 5 bonded to one side. The upper pendulum assembly 1 and the lower pendulum assembly 3 provide two inertial masses for sensor-sensing acceleration. Each pendulum assembly has a quartz resonator 5 attached to one side, which converts the acceleration signals sensed by the inertial masses 6-9 into axial force signals of the quartz resonator 5, and then into frequency change signals of the quartz resonator 5. The two pendulum assemblies are symmetrical about their axis. When the same acceleration signal is input, the frequency of the quartz resonator 5 of one pendulum assembly increases while the frequency of the quartz resonator 5 of the other pendulum assembly decreases, resulting in a differential measurement. This doubles the output of the accelerometer compared to a single pendulum assembly, thereby doubling the sensitivity of the accelerometer. In addition, during the design process, the sensitivity can be further improved by adjusting the size of the inertial mass blocks 6-9 along the length direction of the quartz resonator.

[0052] The interference-resistant, highly sensitive integrated quartz resonant accelerometer chip structure of the present invention can suppress complex interference stresses on the metal pendulum 6, ensuring that the quartz resonator 5 is protected from external and internal interference, thereby improving the long-term stability of the accelerometer. Furthermore, the symmetrical arrangement of the upper pendulum assembly 1 and the lower pendulum assembly 3 in the present invention implements a dual inertial mass structure for differential measurement of acceleration signals, effectively improving the sensitivity of the sensor. Ultimately, the design and manufacture of a highly sensitive quartz resonant accelerometer chip that is resistant to external interference and exhibits excellent long-term stability are achieved. Specific advantages are as follows:

[0053] (1) The provision of the annular stress isolation groove 6-2 can expand the path for external interference stress and assembly residual stress to be transmitted from the anchor plate 6-8 to the quartz resonator 5, thereby reducing the influence of interference stress;

[0054] (2) The setting of the double "C" stress isolation groove 6-1 further increases the path for the external environment interference stress and assembly residual stress to be transmitted to the quartz resonator, and has a significant inhibitory effect on the thermal stress between heterogeneous materials and the residual stress generated when the quartz resonator 5 and the metal pendulum 6 are assembled, further reducing the influence of complex interference stress;

[0055] (3) The metal pendulum 6 is mounted on one side of the quartz resonator 5. The differential layout of the symmetrical mounting structure of the pendulum assembly can double the sensitivity of the accelerometer.

Claims

1. An anti-interference, high-sensitivity integrated quartz resonant accelerometer chip structure, including a pendulum platform, characterized by: The upper pendulum assembly is connected to the upper part of the pendulum platform, and the lower pendulum assembly is connected to the lower part of the pendulum platform; the upper pendulum assembly and the lower pendulum assembly have the same structure and are symmetrically arranged about the pendulum platform; The upper pendulum assembly includes a quartz resonator and a metal pendulum assembled by glue; the quartz resonator includes a double-ended fixed tuning fork structure and an upper fixed plate and a lower fixed plate connected at both ends; The metal pendulum includes a double "C" stress isolation groove, an annular stress isolation groove, a first quartz resonator auxiliary alignment groove, a vibration beam suspension groove, a hinge, a first assembly alignment groove, a mass block isolation groove, an anchor plate, an inertial mass block and a second quartz resonator auxiliary alignment groove; The annular stress isolation groove is symmetrically arranged about the vertical symmetry axis 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. The annular stress isolation groove is connected to the mass block isolation groove, so that the double "C" stress isolation groove, hinge, and inertial mass block are suspended. The two "C"-shaped isolation grooves of the double "C" stress isolation groove are arranged in an interlocking state. A first quartz resonator auxiliary alignment groove is provided on the inner groove of the double "C" stress isolation groove. A vibration beam suspension groove is arranged inside and below the double "C" stress isolation groove. Vibration beam suspension grooves are provided on the front and back of the metal pendulum. The hinge is symmetrically arranged about the vertical axis of symmetry of the metal pendulum structure when viewed from above. Its cross-sectional shape partially coincides with the cross-sectional contour lines of two identical circles of the hinge structure, and is symmetrical about the vertical axis of symmetry and the horizontal axis of symmetry of the hinge structure. One end of the hinge is connected to the lower metal pendulum of the double "C" stress isolation groove, and the other end is connected to the inertial mass block. The inertial mass block is symmetrical about the vertical symmetry axis of the metal pendulum structure when viewed from above. A second quartz resonator auxiliary alignment groove is arranged on the inertial mass block, which cooperates with the first quartz resonator auxiliary alignment groove in the double "C" stress isolation groove to achieve precise alignment and assembly of the quartz resonator and the metal pendulum. The inertial mass block and the anchor plate are separated by the mass block isolation groove. The anchor plate is symmetrically arranged about the vertical symmetry axis of the metal pendulum structure when viewed from above, and is provided with a first assembly alignment groove for assembling the chip structure. The first assembly alignment groove is symmetrically arranged about the vertical symmetry axis of the metal pendulum structure when viewed from above.

2. The structure according to claim 1, characterized in that: The upper and lower surfaces of the pendulum assembly platform are symmetrical about the symmetry axis of the chip cross-sectional structure, and are both provided with an assembly limit groove, a circuit board mounting plane, a pendulum structure suspension groove, a second assembly alignment groove and a metal pendulum mounting plane; The metal pendulum mounting plane has the same shape as the anchor plate of the metal pendulum and is symmetrically arranged about the symmetry axis of the pendulum platform when viewed from above. The arrangement of the pendulum structure suspension slot is such that after the upper pendulum assembly and the pendulum group platform are assembled, the inertial mass block, annular stress isolation slot, double "C" stress isolation slot and hinge portion of the metal pendulum are suspended, and the pendulum structure suspension slot is symmetrically arranged about the structural symmetry axis of the pendulum group platform when viewed from above. After the upper pendulum assembly is assembled with the pendulum group platform, the bottom surface of the suspended slot of the pendulum structure and the lower plane of the inertial mass block form an air cavity for squeeze film damping. The squeeze film damping is set by adjusting the depth of the suspended slot of the pendulum structure. After the upper pendulum assembly is assembled with the pendulum group platform, the height of the upper surface of the quartz resonator is lower than the mounting plane of the circuit board.

3. The structure according to claim 1, characterized in that: The metal pendulum and pendulum assembly platform are both manufactured using precision machining technology, wherein the hinge is processed to the corresponding curvature and thickness by stamping.

4. The structure according to claim 1, characterized in that: The quartz resonator is manufactured by a quartz MEMS wet etching process.

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