Micro-electromechanical sensor and manufacturing method thereof

Abstract

Disclosed are a microelectromechanical sensor and a manufacturing method thereof. The microelectromechanical sensor comprises: a buried layer located on a substrate, with multiple detection electrodes and multiple wiring electrodes disposed on the buried layer; a torsion pendulum arm located above the multiple detection electrodes and the multiple wiring electrodes, wherein the torsion pendulum arm, the multiple detection electrodes, and the multiple wiring electrodes do not contact each other; a torsion pendulum and multiple movable torsion pendulum blocks located above the torsion pendulum arm, wherein the multiple movable torsion pendulum blocks are connected to the torsion pendulum via the torsion pendulum arm, and the multiple movable torsion pendulum blocks and the torsion pendulum arm form a movable structure; multiple fixed electrodes located above the torsion pendulum arm; a support wall located on the buried layer, a protective wall located on the support wall, the support wall and the protective wall forming a cavity, and the movable structure, the torsion pendulum, the multiple detection electrodes, the multiple wiring electrodes, and the multiple fixed electrodes being located in the cavity. Embodiments of the present invention improve the sensitivity of the microelectromechanical sensor and alleviate the problem of the movable structure fracturing under impact.

Description

Technical Field

[0001] The present invention relates to the field of MEMS technology, and in particular to a micro-electromechanical sensor and a manufacturing method thereof. Background Art

[0002] Since its advent, microelectromechanical sensors (MEMS sensors) have attracted widespread attention for their advantages such as small size, low cost, high reliability, low power consumption, strong resistance to harsh environments, and easy integration. Among them, the sensitive structure of the MEMS Z-axis accelerometer is a torsion pendulum accelerometer. The existing method of improving the sensitivity of torsion pendulum accelerometers mainly increases the area of the accelerometer, so that when the mechanical sensitivity is low, the sensitivity of the accelerometer can be improved by increasing the area. However, increasing the area of the torsion pendulum accelerometer increases the manufacturing cost. In addition, when the torsion pendulum accelerometer is operating, a sudden overload causes the movable structure of the accelerometer to deviate in the vertical direction, and the movable structure may break under impact. Therefore, there is an urgent need to provide a microelectromechanical sensor and a manufacturing method thereof, which can improve the sensitivity of the microelectromechanical sensor without increasing the area of the microelectromechanical sensor, and at the same time, improve the problem of the movable structure of the microelectromechanical sensor breaking under impact. Summary of the Invention

[0003] In view of the above problems, the object of the present invention is to provide a micro-electromechanical sensor and a manufacturing method thereof, which improves the sensitivity of the micro-electromechanical sensor without increasing the area of the micro-electromechanical sensor and improves the problem of the movable structure of the micro-electromechanical sensor breaking under impact.

[0004] According to a first aspect of an embodiment of the present invention, there is provided a micro-electromechanical sensor, comprising:

[0005] substrate;

[0006] a buried layer, located on the substrate, on which a plurality of detection electrodes and a plurality of wiring electrodes are arranged;

[0007] a torsion swing arm, the torsion swing arm being located above the plurality of detection electrodes and the plurality of wiring electrodes, the torsion swing arm not being in contact with the plurality of detection electrodes and the plurality of wiring electrodes;

[0008] a pendulum and a plurality of movable pendulum blocks, wherein the pendulum and the plurality of movable pendulum blocks are located above the pendulum arm, the plurality of movable pendulum blocks are connected to the pendulum via the pendulum arm, and the plurality of movable pendulum blocks and the pendulum arm form a movable structure;

[0009] a plurality of fixed electrodes, wherein the plurality of fixed electrodes are located above the torsion swing arm;

[0010] A supporting wall and a protective wall, wherein the supporting wall is located on the buried layer, the protective wall is located on the supporting wall, the supporting wall and the protective wall enclose a cavity, and the movable structure, the torsion, the multiple detection electrodes, the multiple wiring electrodes and the multiple fixed electrodes are located in the cavity.

[0011] Optionally, the torsion swing arm includes: a first braking structure, which provides left-right braking for the movable structure.

[0012] Optionally, the torsion swing arm includes: a first braking structure, which provides upward braking for the movable structure.

[0013] Optionally, the torsion swing arm includes: a first braking structure, which provides braking in left and right directions and upward directions for the movable structure.

[0014] Optionally, the micro-electromechanical sensor further includes:

[0015] A second braking structure is located on the substrate, and the second braking structure provides downward braking for the movable structure.

[0016] Optionally, the torsion swing arm includes: a first braking structure, and the micro-electromechanical sensor further includes: a second braking structure located on the substrate,

[0017] The first braking structure and the second braking structure provide braking for the movable structure in up, down, left and right directions.

[0018] Optionally, the first braking structure includes: a first braking spring located at the first end of the torsion swing arm and a second braking spring located at the second end of the torsion swing arm.

[0019] Optionally, the buried layer includes: a plurality of first protrusions, and the plurality of wiring electrodes respectively cover the plurality of first protrusions.

[0020] Optionally, the micro-electromechanical sensor further includes: a plurality of second protrusions located on the substrate, and the plurality of first protrusions respectively cover the plurality of second protrusions.

[0021] Optionally, the second braking structure includes a plurality of protrusion structures, and the plurality of protrusion structures include the plurality of second protrusions, the plurality of first protrusions corresponding to the plurality of second protrusions, and the plurality of wiring electrodes.

[0022] Optionally, the plurality of detection electrodes include: a first detection electrode and a second detection electrode; the plurality of fixed electrodes include: a first fixed electrode and a second fixed electrode located on both sides of the torsion pendulum;

[0023] The first detection electrode and the second detection electrode respectively form differential capacitances with the torsion swing arm, and the first fixed electrode and the second fixed electrode respectively form differential capacitances with the torsion swing arm.

[0024] Optionally, the plurality of movable torsion pendulum blocks include: a first movable torsion pendulum block and a second movable torsion pendulum block located on both sides of the torsion pendulum, and the masses of the first movable torsion pendulum block and the second movable torsion pendulum block are different.

[0025] Optionally, the first movable torsion pendulum block includes a plurality of sub-movable torsion pendulum blocks.

[0026] Optionally, the first braking structure of the torsion swing arm is located below the protective wall.

[0027] Optionally, the distance between the inner side wall of the protective wall and the plurality of movable torsion pendulum blocks is greater than the distance between the first braking structure and the inner side wall of the supporting wall.

[0028] Optionally, the supporting wall includes: a first sacrificial layer, a second sacrificial layer and a portion of the first structural layer.

[0029] Optionally, the material of the first sacrificial layer includes silicon dioxide.

[0030] Optionally, the thickness of the first sacrificial layer is 0.5 to 2 um.

[0031] Optionally, the material of the second sacrificial layer includes silicon dioxide.

[0032] Optionally, the thickness of the second sacrificial layer is 0.5 to 2 um.

[0033] Optionally, the material of the first brake spring and the second brake spring includes: soft material.

[0034] Optionally, the micro-electromechanical sensor includes a torsion pendulum accelerometer.

[0035] According to a second aspect of an embodiment of the present invention, there is provided a method for manufacturing a micro-electromechanical sensor, comprising:

[0036] forming a buried layer on the substrate;

[0037] forming a plurality of detection electrodes and a plurality of wiring electrodes on the buried layer;

[0038] forming a support wall on the buried layer;

[0039] forming a torsion swing arm in the support wall;

[0040] forming a protective wall, a pendulum, a plurality of fixed electrodes and a plurality of movable pendulum blocks on the supporting wall;

[0041] A cavity is formed in the supporting wall and the protective wall, the multiple movable torsion pendulum blocks are connected to the torsion pendulum through the torsion pendulum arm, the multiple movable torsion pendulum blocks and the torsion pendulum arm form a movable structure, and the movable structure, the torsion pendulum, the multiple detection electrodes, the multiple wiring electrodes and the multiple fixed electrodes are located in the cavity.

[0042] Optionally, forming a torsion swing arm in the supporting wall includes:

[0043] The torsion swing arm is formed, and the torsion swing arm includes: a first braking structure, and the first braking structure provides left and right braking for the movable structure.

[0044] Optionally, forming a torsion swing arm in the supporting wall includes:

[0045] The torsion swing arm is formed, and the torsion swing arm includes: a first braking structure, and the first braking structure provides upward braking for the movable structure.

[0046] Optionally, forming a torsion swing arm in the supporting wall includes:

[0047] The torsion swing arm is formed and includes a first braking structure, which provides braking for the movable structure in left and right directions and upward directions.

[0048] Optionally, the manufacturing method further comprises: forming a second braking structure on the substrate, wherein the second braking structure provides downward braking for the movable structure.

[0049] Optionally, forming a torsion swing arm in the supporting wall comprises: forming the torsion swing arm, the torsion swing arm comprising: a first braking structure;

[0050] The manufacturing method further includes: forming a second braking structure on the substrate;

[0051] The first braking structure and the second braking structure provide braking for the movable structure in up, down, left and right directions.

[0052] Optionally, the first braking structure includes: a first braking spring located at the first end of the torsion swing arm and a second braking spring located at the second end of the torsion swing arm.

[0053] Optionally, forming the second braking structure on the substrate includes: forming a plurality of first protrusions on the buried layer, and the plurality of wiring electrodes respectively cover the plurality of first protrusions.

[0054] Optionally, before forming a plurality of first protrusions on the buried layer, the method further includes:

[0055] A plurality of second protrusions are formed on the substrate, and the plurality of first protrusions respectively cover the plurality of second protrusions.

[0056] Optionally, the second braking structure includes a plurality of protrusion structures, and the plurality of protrusion structures include: the plurality of second protrusions, the plurality of first protrusions corresponding to the plurality of second protrusions, and the plurality of wiring electrodes.

[0057] Optionally, the supporting wall includes: a first sacrificial layer, a second sacrificial layer and a portion of the first structural layer, and forming the supporting wall on the buried layer includes:

[0058] forming a first sacrificial layer on the buried layer, the first sacrificial layer covering the plurality of detection electrodes, the plurality of wiring electrodes and the exposed buried layer, and planarizing and patterning the first sacrificial layer to form a plurality of fourth protrusions;

[0059] forming the first structural layer on the first sacrificial layer, patterning the first structural layer so that the first structural layer covers the first sacrificial layer and exposes the plurality of fourth protrusions, wherein the first structural layer located inside the plurality of fourth protrusions forms a first portion of the first structural layer, and the first structural layer located outside the plurality of fourth protrusions forms a second portion of the first structural layer;

[0060] A second sacrificial layer is formed on the first structural layer, and the second sacrificial layer is planarized and patterned so that a first opening and a second opening are formed in the second sacrificial layer to expose the first structural layer.

[0061] Optionally, forming a protective wall, a torsion pendulum, a plurality of fixed electrodes and a plurality of movable torsion pendulum blocks on the supporting wall includes:

[0062] A second structural layer is formed on the second sacrificial layer, and the second structural layer is flattened and patterned so that the second structural layer covering the first opening and the second opening forms the multiple movable torsion pendulum blocks, the second structural layer located inside the first opening and the second opening forms the torsion pendulum and the multiple fixed electrodes, and the second structural layer located outside the first opening and the second opening forms the protective wall.

[0063] Optionally, forming a cavity in the support wall and the protection wall comprises:

[0064] The first sacrificial layer and the second sacrificial layer located on the inner side of the multiple fourth protrusions are corroded to form the cavity, so that the first part of the first structural layer forms the torsion arm, and the first sacrificial layer, the second sacrificial layer and the second part of the first structural layer located on the outer side of the multiple fourth protrusions form the support wall.

[0065] Optionally, the plurality of detection electrodes include a first detection electrode and a second detection electrode;

[0066] The plurality of fixed electrodes include a first fixed electrode and a second fixed electrode located on both sides of the torsion wobble;

[0067] The plurality of movable torsion pendulum blocks include a first movable torsion pendulum block and a second movable torsion pendulum block located on both sides of the torsion pendulum;

[0068] The first detection electrode and the second detection electrode respectively form differential capacitances with the torsion pendulum arm, the first fixed electrode and the second fixed electrode respectively form differential capacitances with the torsion pendulum arm, and the masses of the first movable torsion pendulum block and the second movable torsion pendulum block are different.

[0069] Optionally, the first braking structure of the torsion swing arm is located below the protective wall.

[0070] Optionally, the distance between the inner side wall of the protective wall and the plurality of movable torsion pendulum blocks is greater than the distance between the first braking structure and the inner side wall of the supporting wall.

[0071] Optionally, the first opening includes a plurality of sub-openings, and the first movable torsion pendulum block includes a plurality of sub-movable torsion pendulum blocks.

[0072] Optionally, the material of the first sacrificial layer includes silicon dioxide.

[0073] Optionally, the thickness of the first sacrificial layer is 0.5 to 2 um.

[0074] Optionally, the material of the second sacrificial layer includes silicon dioxide.

[0075] Optionally, the thickness of the second sacrificial layer is 0.5 to 2 um.

[0076] Optionally, the material of the first brake spring and the second brake spring includes: soft material.

[0077] Optionally, the micro-electromechanical sensor includes a torsional accelerometer.

[0078] According to an embodiment of the present invention, a microelectromechanical sensor and a manufacturing method thereof are provided. A buried layer is provided with multiple detection electrodes and multiple wiring electrodes. A torsion pendulum arm is positioned above the multiple detection electrodes and multiple wiring electrodes, and the torsion pendulum arm, the multiple detection electrodes, and the multiple wiring electrodes do not contact each other. A torsion pendulum and multiple movable torsion pendulum blocks are positioned above the torsion pendulum arm. The multiple movable torsion pendulum blocks are connected to the torsion pendulum via the torsion pendulum arm, and the multiple movable torsion pendulum blocks and the torsion pendulum arm form a movable structure. Multiple fixed electrodes are positioned above the torsion pendulum arm. A support wall is positioned on the buried layer, and a protective wall is positioned on the support wall. The support wall and the protective wall enclose a cavity. The movable structure, the torsion pendulum, the multiple detection electrodes, the multiple wiring electrodes, and the multiple fixed electrodes are positioned within the cavity. The first fixed electrode and the torsion pendulum arm form a first variable capacitor, the second fixed electrode and the torsion pendulum arm form a second variable capacitor, the first detection electrode and the torsion pendulum arm form a third variable capacitor, and the second detection electrode and the torsion pendulum arm form a fourth variable capacitor. The first variable capacitor and the second variable capacitor form a differential capacitor pair. The third variable capacitor and the fourth variable capacitor form a differential capacitor pair. The acceleration value can be obtained by measuring the changes of two pairs of differential capacitors, thereby improving the sensitivity of the micro-electro-mechanical sensor without increasing the area of the micro-electro-mechanical sensor.

[0079] The plurality of second protrusions, the corresponding plurality of first protrusions, and the plurality of first wiring electrodes form a plurality of protrusion structures, and the plurality of protrusion structures form a second braking structure. The second braking structure is located below the torsion pendulum arm. When the movable structure moves downward, the second braking structure prevents the torsion pendulum arm from continuing to move downward, thereby limiting the downward movement range of the movable structure. The first braking structure of the torsion pendulum arm is located below the protective wall. When the movable structure moves upward, the first braking structure prevents the torsion pendulum arm from continuing to move upward, thereby limiting the upward movement range of the movable structure. The distance between the inner wall of the protective wall and the movable torsion pendulum block is greater than the distance between the first braking structure and the inner wall of the supporting wall. When the movable structure moves left or right, the first braking structure first hits the inner wall of the supporting wall, preventing the movable torsion pendulum block from hitting the inner wall of the protective wall. Thus, the first braking structure limits the leftward or rightward movement range of the movable structure. The first braking structure and the second braking structure serve as mechanical stops to limit the lateral and longitudinal movements of the movable structure within a certain range, thereby improving the problem of the movable structure being damaged under certain mechanical impacts and improving the reliability of the micro-electromechanical sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0081] Figure 1 shows a schematic structural diagram of a traditional micro-electromechanical sensor;

[0082] Figure 2 Shown Figure 1A top view of a conventional MEMS sensor is shown;

[0083] Figure 3 A schematic structural diagram of a micro-electromechanical sensor according to an embodiment of the present invention is shown;

[0084] Figure 4 Shown Figure 3 A top view of a micro-electromechanical sensor according to an embodiment of the present invention is shown;

[0085] Figures 5a to 5h sectional views at different stages of a method for manufacturing a micro-electromechanical sensor according to an embodiment of the present invention are shown. DETAILED DESCRIPTION

[0086] Various embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. In each of the accompanying drawings, identical elements are represented by identical or similar reference numerals. For the sake of clarity, the various parts in the accompanying drawings are not drawn to scale.

[0087] The specific implementation of the present invention is further described in detail below with reference to the accompanying drawings and examples.

[0088] Figure 1 Figure 2 shows a schematic structural diagram of a traditional micro-electromechanical sensor. Figure 2 Shown Figure 1 A top view of a conventional MEMS sensor is shown. Figure 1 and Figure 2 The conventional micro-electromechanical sensor 100 shown in FIG is specifically a torsion pendulum acceleration sensor. Figure 1 and Figure 2As shown, the microelectromechanical sensor 100 includes: a substrate 110; a buried layer 120 located on the substrate 110; a first detection electrode 131 and a second detection electrode 132 located on the buried layer 120; a support wall 141 located on the buried layer 120; a protective wall 151, a first movable electrode 152, a second movable electrode 153, and a dangle 154 located on the support wall 141. The support wall 141 and the protective wall 151 enclose a cavity 160. The first detection electrode 131, the second detection electrode 132, the first movable electrode 152, the second movable electrode 153, and the dangle 154 are located in the cavity 160. The first movable electrode 152 and the first detection electrode 131 form a first variable capacitor, while the second movable electrode 153 and the second detection electrode 132 form a second variable capacitor. The first and second variable capacitors form a differential capacitor pair. The first and second movable electrodes 152 and 153 form the movable structure of the microelectromechanical sensor 100. When there is an acceleration perpendicular to the first movable electrode 152 and the second movable electrode 153, the first movable electrode 152 and the second movable electrode 153 twist around the torsion pendulum 154, thereby changing the capacitance of the differential capacitor pair of the first variable capacitor and the second variable capacitor. The acceleration value can be obtained by measuring the capacitance change of the first variable capacitor and the second variable capacitor. Figure 1 and Figure 2 The conventional MEMS sensor 100 shown includes two variable capacitors. The main method for improving sensitivity is to increase the area of the MEMS sensor. When the mechanical sensitivity is low, the sensitivity of the MEMS sensor can be improved by increasing the area. However, increasing the area of the MEMS sensor increases the manufacturing cost of the MEMS sensor. In addition, Figure 1 and Figure 2 When the conventional MEMS sensor 100 is in operation, a sudden overload may cause the movable structure of the MEMS sensor 100 to deviate in the vertical direction, and the movable structure may be easily broken under the impact.

[0089] To solve the above problems, an embodiment of the present invention provides a micro-electromechanical sensor and a manufacturing method thereof. The structure of the micro-electromechanical sensor and the manufacturing method of the micro-electromechanical sensor in the embodiment of the present invention are described in detail below with reference to the accompanying drawings.

[0090] Figure 3 FIG. 4 shows a schematic structural diagram of a micro-electromechanical sensor according to an embodiment of the present invention. Figure 4 Shown Figure 3 FIG. 1 is a top view of a micro-electromechanical sensor according to an embodiment of the present invention. Figure 3 and Figure 4 The micro-electromechanical sensor 200 shown in FIG is specifically a torsion pendulum acceleration sensor. Figure 3 and Figure 4As shown, the micro-electromechanical sensor 200 includes: a substrate 210, the material of the substrate 210 includes: single crystal silicon, the crystal orientation of the single crystal silicon is <100> A buried layer 230 is located on the substrate 210 and includes a first protrusion 231 and a first protrusion 232. The buried layer 230 is made of silicon dioxide and has a thickness of 0.5 to 5 μm. Preferably, the buried layer 230 has a thickness of 1.5 to 2.5 μm. The first protrusions 231 and 232 are made of silicon dioxide and have a thickness of 0.1 to 2 μm. Preferably, the first protrusions 231 and 232 have a thickness of 0.3 to 1 μm. In some embodiments, the microelectromechanical sensor 200 further includes a second protrusion 221 and a second protrusion 222. The second protrusions 221 and 222 are located on the substrate 210, with the first protrusion 231 covering the second protrusion 221 and the first protrusion 232 covering the second protrusion 222. The second protrusions 221 and 222 are made of silicon, silicon dioxide, polysilicon, or silicon nitride and have a thickness of 0.1 to 2 μm. The first detection electrode 243, the second detection electrode 244, the first wiring electrode 241, and the second wiring electrode 242 are located on the buried layer 230. The first wiring electrode 241 covers the first protrusion 231 to form a protrusion, and the second wiring electrode 242 covers the first protrusion 232 to form a protrusion. The first detection electrode 243, the second detection electrode 244, the first wiring electrode 241, and the second wiring electrode 242 are made of polycrystalline silicon with a thickness of 0.1 to 1 μm and a resistivity of less than 30 Ω·cm. Preferably, the first detection electrode 243, the second detection electrode 244, the first wiring electrode 241, and the second wiring electrode 242 have a thickness of 0.3 to 0.6 μm and a resistivity of less than 10 Ω·cm. The torsion pendulum arm 261 is located above the first detection electrode 243, the second detection electrode 244, the first wiring electrode 241, and the second wiring electrode 242. The first detection electrode 243, the second detection electrode 244, the first wiring electrode 241, the second wiring electrode 242, and the torsion pendulum arm 261 do not contact each other. The torsion pendulum 284, the first movable torsion pendulum block 281, and the second movable torsion pendulum block 282 are located on both sides of the torsion pendulum 284. The torsion pendulum 284, the first movable torsion pendulum block 281, and the second movable torsion pendulum block 282 are located above the torsion pendulum arm 261. The first movable torsion pendulum block 281 and the second movable torsion pendulum block 282 are connected to the torsion pendulum 284 via the torsion pendulum arm 261. The first movable torsion pendulum block 281, the second movable torsion pendulum block 282, and the torsion pendulum arm 261 form a movable structure. The masses of the first movable torsion pendulum block 281 and the second movable torsion pendulum block 282 are unequal. Specifically, the first movable torsion pendulum block 281 includes a plurality of sub-movable torsion pendulum blocks 283 .

[0091] The MEMS sensor 200 further includes a first fixed electrode 285 and a second fixed electrode 286 located on either side of the wobble 284, with the first and second fixed electrodes 285 and 286 located above the wobble arm 261; a support wall 290 and a protective wall 287. The support wall 290 is located on the buried layer 230, and the protective wall 287 is located on the support wall 290. The support wall 290 and the protective wall 287 enclose a cavity 291. The movable structure, the wobble 284, the first detection electrode 243, the second detection electrode 244, the first wiring electrode 241, the second wiring electrode 242, the first fixed electrode 285, and the second fixed electrode 286 are located in the cavity 291. The first movable wobble 281, the second movable wobble 282, the wobble 284, the first fixed electrode 285, the second fixed electrode 286, and the protective wall 287 are made of polysilicon with a thickness ranging from 10 to 50 μm and a resistivity of less than 30 Ω·cm. Preferably, the thickness of the first movable pendulum block 281 , the second movable pendulum block 282 , the pendulum 284 , the first fixed electrode 285 , the second fixed electrode 286 and the protection wall 287 is 15 to 25 μm, and the resistivity is less than 10 Ω·cm.

[0092] The torsion pendulum arm 261 includes a first braking structure. The first braking structure of the torsion pendulum arm 261 is located below the protective wall 287. The first braking structure provides leftward and rightward and / or upward braking for the movable structure. The first braking structure includes a first braking spring 263 located at the first end of the torsion pendulum arm 261 and a second braking spring 264 located at the second end of the torsion pendulum arm 261. The distance between the inner wall of the protective wall 287 and the first movable torsion pendulum block 281 is greater than the distance between the first braking spring 263 and the inner wall of the support wall 290. The distance between the inner wall of the protective wall 287 and the second movable torsion pendulum block 282 is greater than the distance between the second braking spring 264 and the inner wall of the support wall 290. MEMS sensor 200 further includes a second braking structure comprising a first protrusion structure and a second protrusion structure. The first wiring electrode 241, the first protrusion 231, and the second protrusion 221 form the first protrusion structure, while the second wiring electrode 242, the first protrusion 232, and the second protrusion 222 form the second protrusion structure. The second braking structure provides downward braking for the movable structure.

[0093] The support wall 290 includes a first sacrificial layer 250, a second sacrificial layer 270, and a portion of the first structural layer 260. The first sacrificial layer 250 is located on the buried layer 230, the first structural layer 260 is located on the first sacrificial layer 250, and the second sacrificial layer 270 is located on the first structural layer 260. The first sacrificial layer 250 is made of silicon dioxide, with a thickness ranging from 0.5 to 2 μm. Alternative materials for the first sacrificial layer 250 include SiO2 prepared from tetraethylorthosilicate (TEOS) and low-temperature chemical vapor deposited SiO2 (LTO). Preferably, the first sacrificial layer 250 has a thickness ranging from 0.7 to 1.5 μm. The first structural layer 260 is made of polycrystalline silicon, with a thickness ranging from 0.5 to 5 μm and a resistivity less than 30 Ω·cm. Preferably, the first structural layer 260 has a thickness ranging from 0.75 to 2 μm and a resistivity less than 10 Ω·cm. The second sacrificial layer 270 is made of silicon dioxide, with a thickness ranging from 0.5 to 2 μm. Preferably, the thickness of the second sacrificial layer 270 is 0.7 to 1.5 μm. Optional materials for the second sacrificial layer 270 also include SiO 2 prepared from tetraethylorthosilicate (TEOS) and low temperature chemical vapor deposition SiO 2 (LTO).

[0094] The first braking structure (first braking spring 263 and second braking spring 264) of the torsion swing arm 261 is located below the protective wall 287. When the movable structure moves upward, the first braking spring 263 and second braking spring 264 prevent the torsion swing arm 261 from further upward movement, thereby limiting the upward movement range of the movable structure. The second braking structure (first protrusion structure and second protrusion structure) is located below the torsion swing arm 261. When the movable structure moves downward, the second braking structure prevents the torsion swing arm 261 from further downward movement, thereby limiting the downward movement range of the movable structure. The distance between the inner sidewall of protective wall 287 and the movable torsion pendulum blocks (first movable torsion pendulum block 281 and second movable torsion pendulum block 282) is greater than the distance between the first braking structure (first braking spring 263 and second braking spring 264) and the inner sidewall of support wall 290. When the movable structure moves leftward, the first braking spring 263 first strikes the inner sidewall of support wall 290, preventing the first movable torsion pendulum block 281 from striking the inner sidewall of protective wall 287. The first braking structure (first braking spring 263) limits the leftward movement of the movable structure. When the movable structure moves rightward, the second braking spring 264 first strikes the inner sidewall of support wall 290, preventing the second movable torsion pendulum block 282 from striking the inner sidewall of protective wall 287. The first braking structure (second braking spring 264) limits the rightward movement of the movable structure. The material of the first brake spring 263 and the second brake spring 264 includes soft elastic material. When the movable structure moves up and down and left and right and collides, the first brake spring 263 and the second brake spring 264 play a buffering role, improving the phenomenon of the movable structure breaking under impact, and improving the reliability of the micro-electromechanical sensor 200.

[0095] The first fixed electrode 285 and the torsion pendulum arm 261 form a first variable capacitor, the second fixed electrode 286 and the torsion pendulum arm 261 form a second variable capacitor, the first detection electrode 243 and the torsion pendulum arm 261 form a third variable capacitor, and the second detection electrode 244 and the torsion pendulum arm 261 form a fourth variable capacitor. The first variable capacitor and the second variable capacitor form a pair of differential capacitors. The third variable capacitor and the fourth variable capacitor form a pair of differential capacitors. When there is an acceleration perpendicular to the movable structure, the first movable torsion pendulum block 281 and the second movable torsion pendulum block 282 twist about the torsion pendulum 284, causing the differential capacitance of the first and second variable capacitors to change, and the differential capacitance of the third and fourth variable capacitors to change. By measuring the change from the first to the fourth variable capacitance, the acceleration value of the microelectromechanical sensor 200 can be obtained. The microelectromechanical sensor 200 includes four variable capacitors (two pairs of differential capacitors) and detects the acceleration value by changing the four variable capacitors (two pairs of differential capacitors), which improves the sensitivity of the microelectromechanical sensor 200.

[0096] Figures 5a to 5h sectional views of different stages of a method for manufacturing a micro-electromechanical sensor according to an embodiment of the present invention are shown. Figures 5a to 5h , the manufacturing method of the micro-electromechanical sensor 200 includes the following steps.

[0097] like Figure 5a As shown, a substrate 210 is provided, and a thin film material is formed on the substrate 210 by conventional semiconductor process methods such as thermal oxidation or low pressure chemical vapor deposition (LPCVD) or plasma enhanced chemical vapor deposition (PECVD). The material of the thin film includes silicon, silicon dioxide, polysilicon and silicon nitride. Then, the thin film material is patterned by conventional semiconductor process methods to form a second protrusion 221 and a second protrusion 222 on the substrate 210. The material of the substrate 210 includes: single crystal silicon, the crystal orientation of the single crystal silicon is <100> The thickness of the second protrusion 221 and the second protrusion 222 is 0.1 to 2 μm. Preferably, the thickness of the second protrusion 221 and the second protrusion 222 is 0.3 to 1 μm. It is easy to understand that the embodiment of the present invention can form the second protrusion 221 and the second protrusion 222 by patterning the substrate 210 using conventional semiconductor processing methods.

[0098] like Figure 5b As shown, a buried layer 230 is formed on the second protrusion 221 and the second protrusion 222 using conventional semiconductor processing methods such as thermal oxidation, low-pressure chemical vapor deposition (LPCVD), or plasma-enhanced chemical vapor deposition (PECVD). The buried layer 230 covers the second protrusion 221 to form the first protrusion 231, and covers the second protrusion 222 to form the first protrusion 232. The material of the buried layer 230 includes silicon dioxide, and the thickness of the buried layer 230 is between 0.5 and 5 μm. Preferably, the thickness of the buried layer 230 is between 1.5 and 2.5 μm. The material of the first protrusion 231 and the first protrusion 232 includes silicon dioxide, and the thickness of the first protrusion 231 and the first protrusion 232 is between 0.1 and 2 μm. Preferably, the thickness of the first protrusion 231 and the first protrusion 232 is between 0.3 and 1 μm.

[0099] It is easy to understand that forming the second protrusion 221 and the second protrusion 222 on the substrate 210 is an optional step. In the embodiment of the present invention, the buried layer 230 and the first protrusion 231 and the first protrusion 232 on the buried layer 230 can also be directly formed on the substrate. The specific steps may be: providing a substrate 210, forming a buried layer material on the substrate 210 by conventional semiconductor process methods such as thermal oxidation or low-pressure chemical vapor deposition (LPCVD) or plasma-enhanced chemical vapor deposition (PECVD), and then patterning the buried layer material by conventional semiconductor process methods to form the first protrusion 231 and the first protrusion 232 on the buried layer 230.

[0100] like Figure 5c As shown, a wiring layer material is deposited on buried layer 230 using conventional semiconductor processing methods such as low-pressure chemical vapor deposition (LPCVD). This wiring layer material is then patterned using processes such as photolithography and etching to form wiring layer 240. Wiring layer 240 includes a first detection electrode 243, a second detection electrode 244, a first wiring electrode 241, and a second wiring electrode 242. First wiring electrode 241 covers first protrusion 231 to form a protrusion, while second wiring electrode 242 covers first protrusion 232 to form a protrusion. Second protrusion 221, first protrusion 231, and first wiring electrode 241 form a first protrusion structure, while second protrusion 222, first protrusion 232, and second wiring electrode 242 form a second protrusion structure. The first and second protrusion structures serve as a second brake structure for microelectromechanical sensor 200, providing braking for the movable structure of microelectromechanical sensor 200 formed in a subsequent process in the downward direction. The wiring layer 240 is made of polysilicon, has a thickness of 0.1 to 1 μm, and a resistivity of less than 30 Ω·cm. Preferably, the wiring layer 240 has a thickness of 0.3 to 0.6 μm and a resistivity of less than 10 Ω·cm. It should be noted that the wiring layer 240 may have a roughened surface to prevent adhesion between the first and second wiring electrodes 241, 242 and the subsequently formed torsion arm 261.

[0101] like Figure 5d As shown, a first sacrificial layer material is deposited on the wiring layer 240 using conventional semiconductor processing methods such as thermal oxidation, low-pressure chemical vapor deposition (LPCVD), or plasma-enhanced chemical vapor deposition (PECVD). The first sacrificial layer material is planarized using a chemical mechanical polishing (CMP) process, and then patterned using processes such as photolithography and etching to form a first sacrificial layer 250. The first sacrificial layer 250 covers the first sensing electrode 243, the second sensing electrode 244, the first wiring electrode 241, the second wiring electrode 242, and the exposed buried layer 230. The first sacrificial layer 250 includes a third protrusion 251, a fourth protrusion 252, and a fourth protrusion 253. The fourth protrusions 252 and 253 control the distance between the torsion arm 261 formed in a subsequent process and the support wall 290. The third protrusion 251 controls the shape of the ends of the torsion arm 261 formed in a subsequent process. The first sacrificial layer 250 is made of silicon dioxide and has a thickness ranging from 0.5 to 2 μm. Optional materials for the first sacrificial layer 250 also include: SiO2 prepared from tetraethylorthosilicate (TEOS), low temperature chemical vapor deposition SiO2 (LTO). Preferably, the thickness of the first sacrificial layer 250 is 0.7 to 1.5 μm.

[0102] like Figure 5eAs shown, a first structural layer material is deposited on the first sacrificial layer 250 using conventional semiconductor processing methods such as low-pressure chemical vapor deposition (LPCVD). The first structural layer material is then patterned using processes such as photolithography and etching to form a first structural layer 260. The first structural layer 260 covers the first sacrificial layer 250 and exposes the fourth protrusions 252 and the fourth protrusions 253. The first structural layer 260 located inside the fourth protrusions 252 and the fourth protrusions 253 forms a first portion of the first structural layer 261. The first structural layer 260 located outside the fourth protrusions 252 and the fourth protrusions 253 forms a second portion of the first structural layer 262. The first portion of the first structural layer 261 covering the third protrusion 251 forms a first step 263 at a first end of the first portion of the first structural layer 261, and a second step 264 at a second end of the first portion of the first structural layer 261. In subsequent processes, a torsion arm 261, a first brake spring 263, and a second brake spring 264 will be formed. The material of the first structure layer 260 includes polysilicon, has a thickness of 0.5 to 5 μm, and a resistivity of less than 30 Ω·cm. Preferably, the thickness of the first structure layer 260 includes a thickness of 0.75 to 2 μm, and a resistivity of less than 10 Ω·cm.

[0103] It is easy to understand that in the embodiment of the present invention, a seed layer of the first structural layer material can be deposited on the first sacrificial layer 250 by conventional semiconductor process methods such as low-pressure chemical vapor deposition (LPCVD), the first structural layer material can be epitaxially grown, and then the first structural layer material can be patterned by processes such as lithography and etching to form the first structural layer 260.

[0104] like Figure 5fAs shown, a second sacrificial layer material is deposited on the first structural layer 260 using conventional semiconductor processing methods such as thermal oxidation, low-pressure chemical vapor deposition (LPCVD), or plasma-enhanced chemical vapor deposition (PECVD). The second sacrificial layer material is planarized using a chemical mechanical polishing (CMP) process, and then patterned using processes such as photolithography and etching to form a second sacrificial layer 270. The second sacrificial layer 270 covers the second portion of the first structural layer 262, the fourth protrusion 252, the fourth protrusion 253, and a portion of the first portion of the first structural layer 261. The second sacrificial layer 270 located on the first portion of the first structural layer 261 includes a first opening 271 and a second opening 272, which expose the first portion of the first structural layer 261. Specifically, the first opening 271 includes a plurality of sub-openings 273. The first and second movable torsion blocks 281 and 282 will be subsequently formed in the first and second openings 271 and 272. The second sacrificial layer 270 may be made of silicon dioxide with a thickness of 0.5 to 2 μm. Preferably, the second sacrificial layer 270 may be made of silicon dioxide with a thickness of 0.7 to 1.5 μm. Optional materials for the second sacrificial layer 270 include SiO2 prepared from tetraethylorthosilicate (TEOS) or low-temperature chemical vapor deposited SiO2 (LTO).

[0105] like Figure 5gAs shown, a second structural layer material is deposited on the second sacrificial layer 270 using conventional semiconductor processing methods such as low-pressure chemical vapor deposition (LPCVD). The second structural layer material is planarized using a chemical mechanical polishing (CMP) process, and then patterned using a conventional process such as a BOSCH etching process to form a second structural layer 280. The second structural layer 280 covering the first opening 271 and the second opening 272 forms a first movable pendulum block 281 and a second movable pendulum block 282, respectively. Specifically, the second structural layer 280 covering the plurality of sub-openings 273 forms a plurality of sub-movable pendulum blocks 283. The second structural layer 280 located inside the first opening 271 and the second opening 272 forms a pendulum 284, a first fixed electrode 285, and a second fixed electrode 286. The second structural layer 280 located outside the first opening 271 and the second opening 272 forms a protective wall 287. The first fixed electrode 285 and the second fixed electrode 286 are located on either side of the pendulum 284. A third opening 288 is provided between the first fixed electrode 285 and the pendulum 284, and a third opening 288 is provided between the second fixed electrode 286 and the pendulum 284. A fourth opening 289 is provided between the first fixed electrode 285 and the second movable pendulum block 282, and a fourth opening 289 is provided between the second fixed electrode 286 and the first movable pendulum block 281. A fifth opening 2810 is provided between the protective wall 287 and the first movable pendulum block 281, and a fifth opening 2810 is provided between the protective wall 287 and the second movable pendulum block 282. The first movable pendulum block 281 and the second movable pendulum block 282 have different masses. The material of the second structural layer 280 includes polycrystalline silicon, has a thickness ranging from 10 to 50 μm, and a resistivity less than 30 Ω·cm. Preferably, the thickness of the second structural layer 280 is ranging from 15 to 25 μm, and a resistivity less than 10 Ω·cm.

[0106] In some embodiments, the second structural layer 280 can also be formed by the following manufacturing method: a seed layer of the second structural layer material is deposited on the second sacrificial layer 270 by a conventional semiconductor process method such as low-pressure chemical vapor deposition (LPCVD). The material of the seed layer includes polycrystalline silicon, and the thickness of the seed layer is 0.2 to 0.6 μm. Preferably, the thickness of the seed layer is 0.2 to 0.5 μm. Then, the second structural layer material is epitaxially grown, the second structural layer material is planarized by a chemical mechanical polishing (CMP) process, and then the second structural layer material is patterned by a conventional process such as a BOSCH etching process to form the second structural layer 280.

[0107] like Figure 5hAs shown, conventional semiconductor process techniques such as selective wet etching with HF acid, BOE solution, or vapor phase etching are used to etch the first sacrificial layer 250 and the second sacrificial layer 270 located inside the fourth protrusions 252 and 253 through the third opening 288, the fourth opening 289, and the fifth opening 2810 to form a cavity 291. The first portion of the first structural layer 261 forms a torsion arm 261, the first step 263 forms a first brake spring 263, and the second step 264 forms a second brake spring 264. The first sacrificial layer 250, the second sacrificial layer 270, and a portion of the first structural layer 260 (the second portion of the first structural layer 262) located outside the fourth protrusions 252 and 253 form a support wall 290. The first brake structure (the first brake spring 263 and the second brake spring 264) of the torsion arm 261 is located below the protective wall 287. The distance between the inner sidewall of protective wall 287 and the first movable pendulum 281 is greater than the distance between the first brake spring 263 and the inner sidewall of support wall 290. The distance between the inner sidewall of protective wall 287 and the second movable pendulum 282 is greater than the distance between the second brake spring 264 and the inner sidewall of support wall 290. The first movable pendulum 281, the second movable pendulum 282, and the pendulum arm 261 form the movable structure of the microelectromechanical sensor 200. The movable structure, pendulum 284, the first detection electrode 243, the second detection electrode 244, the first wiring electrode 241, the second wiring electrode 242, the first fixed electrode 285, and the second fixed electrode 286 are located within the cavity 291. The movable structure's range of motion is confined within the cavity. The protective wall 287 and support wall 290 isolate the movable structure from the outside world, thus protecting the device.

[0108] According to an embodiment of the present invention, a microelectromechanical sensor and a manufacturing method thereof are provided. A buried layer is provided with multiple detection electrodes and multiple wiring electrodes. A torsion pendulum arm is positioned above the multiple detection electrodes and multiple wiring electrodes, and the torsion pendulum arm, the multiple detection electrodes, and the multiple wiring electrodes do not contact each other. A torsion pendulum and multiple movable torsion pendulum blocks are positioned above the torsion pendulum arm. The multiple movable torsion pendulum blocks are connected to the torsion pendulum via the torsion pendulum arm, and the multiple movable torsion pendulum blocks and the torsion pendulum arm form a movable structure. Multiple fixed electrodes are positioned above the torsion pendulum arm. A support wall is positioned on the buried layer, and a protective wall is positioned on the support wall. The support wall and the protective wall enclose a cavity. The movable structure, the torsion pendulum, the multiple detection electrodes, the multiple wiring electrodes, and the multiple fixed electrodes are positioned within the cavity. The first fixed electrode and the torsion pendulum arm form a first variable capacitor, the second fixed electrode and the torsion pendulum arm form a second variable capacitor, the first detection electrode and the torsion pendulum arm form a third variable capacitor, and the second detection electrode and the torsion pendulum arm form a fourth variable capacitor. The first variable capacitor and the second variable capacitor form a differential capacitor pair. The third variable capacitor and the fourth variable capacitor form a differential capacitor pair. The acceleration value can be obtained by measuring the changes of two pairs of differential capacitors, thereby improving the sensitivity of the micro-electro-mechanical sensor without increasing the area of the micro-electro-mechanical sensor.

[0109] The plurality of second protrusions, the corresponding plurality of first protrusions, and the plurality of first wiring electrodes form a plurality of protrusion structures, and the plurality of protrusion structures form a second braking structure. The second braking structure is located below the torsion pendulum arm. When the movable structure moves downward, the second braking structure prevents the torsion pendulum arm from continuing to move downward, thereby limiting the downward movement range of the movable structure. The first braking structure of the torsion pendulum arm is located below the protective wall. When the movable structure moves upward, the first braking structure prevents the torsion pendulum arm from continuing to move upward, thereby limiting the upward movement range of the movable structure. The distance between the inner wall of the protective wall and the movable torsion pendulum block is greater than the distance between the first braking structure and the inner wall of the supporting wall. When the movable structure moves left or right, the first braking structure first hits the inner wall of the supporting wall, preventing the movable torsion pendulum block from hitting the inner wall of the protective wall. Thus, the first braking structure limits the leftward or rightward movement range of the movable structure. The first braking structure and the second braking structure serve as mechanical stops to limit the lateral and longitudinal movements of the movable structure within a certain range, thereby improving the problem of the movable structure being damaged under certain mechanical impacts and improving the reliability of the micro-electromechanical sensor.

[0110] While embodiments of the present invention have been described above, these embodiments do not exhaustively describe all details and do not limit the invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the above description. These embodiments are selected and described in detail in this specification in order to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better utilize the present invention and its modifications. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A micro-electromechanical sensor, wherein: include: substrate; a buried layer, located on the substrate, on which a plurality of detection electrodes and a plurality of wiring electrodes are arranged; a torsion swing arm, the torsion swing arm being located above the plurality of detection electrodes and the plurality of wiring electrodes, the torsion swing arm not being in contact with the plurality of detection electrodes and the plurality of wiring electrodes; a pendulum and a plurality of movable pendulum blocks, wherein the pendulum and the plurality of movable pendulum blocks are located above the pendulum arm, the plurality of movable pendulum blocks are connected to the pendulum via the pendulum arm, and the plurality of movable pendulum blocks and the pendulum arm form a movable structure; a plurality of fixed electrodes, wherein the plurality of fixed electrodes are located above the torsion swing arm; A supporting wall and a protective wall, wherein the supporting wall is located on the buried layer, the protective wall is located on the supporting wall, the supporting wall and the protective wall form a cavity, and the movable structure, the torsion, the multiple detection electrodes, the multiple wiring electrodes and the multiple fixed electrodes are located in the cavity.

2. The micro-electromechanical sensor according to claim 1, wherein: The torsion swing arm includes a first braking structure, which provides left-right braking for the movable structure.

3. The micro-electromechanical sensor according to claim 1, wherein: The torsion swing arm includes a first braking structure, which provides upward braking for the movable structure.

4. The micro-electromechanical sensor according to claim 1, wherein: The torsion swing arm includes a first braking structure, which provides braking for the movable structure in left and right directions and upward directions.

5. The micro-electromechanical sensor according to claim 1, wherein: The micro-electromechanical sensor further comprises: A second braking structure is located on the substrate, and the second braking structure provides downward braking for the movable structure. The micro-electromechanical sensor according to claim 1 , wherein: The torsion swing arm includes: a first braking structure, and the micro-electromechanical sensor further includes: a second braking structure located on the substrate, The first braking structure and the second braking structure provide braking for the movable structure in up, down, left and right directions.

7. The micro-electromechanical sensor according to any one of claims 2, 3, 4 and 6, wherein: The first braking structure includes a first braking spring located at a first end of the torsion swing arm and a second braking spring located at a second end of the torsion swing arm.

8. The micro-electromechanical sensor according to claim 5 or 6, wherein: The buried layer includes a plurality of first protrusions, and the plurality of wiring electrodes respectively cover the plurality of first protrusions.

9. The micro-electromechanical sensor according to claim 8, wherein: The micro-electromechanical sensor further includes: a plurality of second protrusions located on the substrate, and the plurality of first protrusions respectively cover the plurality of second protrusions.

10. The micro-electromechanical sensor according to claim 9, wherein: The second braking structure includes a plurality of protrusion structures including the plurality of second protrusions, the plurality of first protrusions corresponding to the plurality of second protrusions, and the plurality of wiring electrodes.

11. The micro-electromechanical sensor according to claim 1, wherein: The plurality of detection electrodes include: a first detection electrode and a second detection electrode; the plurality of fixed electrodes include: a first fixed electrode and a second fixed electrode located on both sides of the torsion pendulum; The first detection electrode and the second detection electrode respectively form differential capacitances with the torsion swing arm, and the first fixed electrode and the second fixed electrode respectively form differential capacitances with the torsion swing arm.

12. The micro-electromechanical sensor according to claim 1, wherein: The plurality of movable torsion pendulum blocks include a first movable torsion pendulum block and a second movable torsion pendulum block located on both sides of the torsion pendulum, and the masses of the first movable torsion pendulum block and the second movable torsion pendulum block are different.

13. The micro-electromechanical sensor according to claim 12, wherein: The first movable torsion pendulum block includes a plurality of sub-movable torsion pendulum blocks.

14. The micro-electromechanical sensor according to any one of claims 2, 3, 4 and 6, wherein: The first braking structure of the torsion swing arm is located below the protective wall.

15. The micro-electromechanical sensor according to any one of claims 2, 3, 4 and 6, wherein: The distance between the inner side wall of the protection wall and the plurality of movable torsion blocks is greater than the distance between the first braking structure and the inner side wall of the support wall.

16. The micro-electromechanical sensor according to claim 1, wherein: The supporting wall includes: a first sacrificial layer, a second sacrificial layer and a portion of a first structural layer.

17. The micro-electromechanical sensor according to claim 16, wherein: The material of the first sacrificial layer includes silicon dioxide.

18. The micro-electromechanical sensor according to claim 16, wherein: The thickness of the first sacrificial layer is 0.5 to 2 μm.

19. The micro-electromechanical sensor according to claim 16, wherein: The material of the second sacrificial layer includes silicon dioxide.

20. The micro-electromechanical sensor according to claim 16, wherein: The thickness of the second sacrificial layer is 0.5 to 2 μm.

21. The micro-electromechanical sensor according to claim 7, wherein: The materials of the first brake spring and the second brake spring include: soft materials.

22. The micro-electromechanical sensor according to claim 1, wherein: The micro-electromechanical sensor includes a torsion pendulum accelerometer.

23. A method for manufacturing a micro-electromechanical sensor, wherein: include: forming a buried layer on the substrate; forming a plurality of detection electrodes and a plurality of wiring electrodes on the buried layer; forming a support wall on the buried layer; forming a torsion swing arm in the support wall; forming a protective wall, a pendulum, a plurality of fixed electrodes and a plurality of movable pendulum blocks on the supporting wall; A cavity is formed in the supporting wall and the protective wall, the multiple movable torsion pendulum blocks are connected to the torsion pendulum through the torsion pendulum arm, the multiple movable torsion pendulum blocks and the torsion pendulum arm form a movable structure, and the movable structure, the torsion pendulum, the multiple detection electrodes, the multiple wiring electrodes and the multiple fixed electrodes are located in the cavity.

24. The manufacturing method according to claim 23, wherein: The forming of a torsion swing arm in the supporting wall comprises: The torsion swing arm is formed, and the torsion swing arm includes: a first braking structure, and the first braking structure provides left and right braking for the movable structure.

25. The manufacturing method according to claim 23, wherein: The forming of a torsion swing arm in the supporting wall comprises: The torsion swing arm is formed, and the torsion swing arm includes: a first braking structure, and the first braking structure provides upward braking for the movable structure.

26. The manufacturing method according to claim 23, wherein: The forming of a torsion swing arm in the supporting wall comprises: The torsion swing arm is formed and includes a first braking structure, which provides braking for the movable structure in left and right directions and upward directions.

27. The manufacturing method according to claim 23, wherein: The manufacturing method further includes forming a second braking structure on the substrate, wherein the second braking structure provides downward braking for the movable structure.

28. The manufacturing method according to claim 23, wherein: The forming of the torsion swing arm in the supporting wall comprises: forming the torsion swing arm, the torsion swing arm comprising: a first braking structure; The manufacturing method further includes: forming a second braking structure on the substrate; The first braking structure and the second braking structure provide braking for the movable structure in up, down, left and right directions.

29. The manufacturing method according to any one of claims 24, 25, 26 and 28, wherein: The first braking structure includes a first braking spring located at a first end of the torsion swing arm and a second braking spring located at a second end of the torsion swing arm.

30. The manufacturing method according to claim 27 or 28, wherein: The forming of the second braking structure on the substrate includes: forming a plurality of first protrusions on the buried layer, and the plurality of wiring electrodes respectively cover the plurality of first protrusions.

31. The manufacturing method according to claim 30, wherein: Before forming a plurality of first protrusions on the buried layer, the method further includes: A plurality of second protrusions are formed on the substrate, and the plurality of first protrusions respectively cover the plurality of second protrusions.

32. The manufacturing method according to claim 31, wherein The second braking structure includes a plurality of protrusion structures, and the plurality of protrusion structures include: the plurality of second protrusions, the plurality of first protrusions corresponding to the plurality of second protrusions, and the plurality of wiring electrodes.

33. The manufacturing method according to claim 23, wherein: The supporting wall includes: a first sacrificial layer, a second sacrificial layer and a portion of the first structural layer, and forming the supporting wall on the buried layer includes: forming a first sacrificial layer on the buried layer, the first sacrificial layer covering the plurality of detection electrodes, the plurality of wiring electrodes and the exposed buried layer, and planarizing and patterning the first sacrificial layer to form a plurality of fourth protrusions; forming the first structural layer on the first sacrificial layer, patterning the first structural layer so that the first structural layer covers the first sacrificial layer and exposes the plurality of fourth protrusions, wherein the first structural layer located inside the plurality of fourth protrusions forms a first portion of the first structural layer, and the first structural layer located outside the plurality of fourth protrusions forms a second portion of the first structural layer; A second sacrificial layer is formed on the first structural layer, and the second sacrificial layer is planarized and patterned so that a first opening and a second opening are formed in the second sacrificial layer to expose the first structural layer.

34. The manufacturing method according to claim 33, wherein: The forming of the protective wall, the pendulum, the plurality of fixed electrodes and the plurality of movable pendulum blocks on the supporting wall comprises: A second structural layer is formed on the second sacrificial layer, and the second structural layer is flattened and patterned so that the second structural layer covering the first opening and the second opening forms the multiple movable torsion pendulum blocks, the second structural layer located inside the first opening and the second opening forms the torsion pendulum and the multiple fixed electrodes, and the second structural layer located outside the first opening and the second opening forms the protective wall.

35. The manufacturing method according to claim 33, wherein: Forming a cavity in the support wall and the protective wall includes: The first sacrificial layer and the second sacrificial layer located on the inner side of the multiple fourth protrusions are corroded to form the cavity, so that the first part of the first structural layer forms the torsion arm, and the first sacrificial layer, the second sacrificial layer and the second part of the first structural layer located on the outer side of the multiple fourth protrusions form the support wall.

36. The manufacturing method according to claim 34, wherein: The plurality of detection electrodes include a first detection electrode and a second detection electrode; The plurality of fixed electrodes include a first fixed electrode and a second fixed electrode located on both sides of the torsion wobble; The plurality of movable torsion pendulum blocks include a first movable torsion pendulum block and a second movable torsion pendulum block located on both sides of the torsion pendulum; The first detection electrode and the second detection electrode respectively form differential capacitances with the torsion pendulum arm, the first fixed electrode and the second fixed electrode respectively form differential capacitances with the torsion pendulum arm, and the masses of the first movable torsion pendulum block and the second movable torsion pendulum block are different.

37. The manufacturing method according to any one of claims 24, 25, 26 and 28, wherein The first braking structure of the torsion swing arm is located below the protective wall.

38. The manufacturing method according to any one of claims 24, 25, 26 and 28, wherein: The distance between the inner side wall of the protection wall and the plurality of movable torsion blocks is greater than the distance between the first braking structure and the inner side wall of the support wall.

39. The manufacturing method according to claim 36, wherein: The first opening includes a plurality of sub-openings, and the first movable torsion pendulum block includes a plurality of sub-movable torsion pendulum blocks.

40. The manufacturing method according to claim 33, wherein: The material of the first sacrificial layer includes silicon dioxide.

41. The manufacturing method according to claim 33, wherein The thickness of the first sacrificial layer is 0.5 to 2 um.

42. The manufacturing method according to claim 33, wherein: The material of the second sacrificial layer includes silicon dioxide.

43. The manufacturing method according to claim 33, wherein: The thickness of the second sacrificial layer is 0.5 to 2 um.

44. The manufacturing method according to claim 29, wherein The materials of the first brake spring and the second brake spring include: soft materials.

45. The manufacturing method according to claim 23, wherein The micro-electromechanical sensor includes a torsion pendulum accelerometer.

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