A vertical comb-finger electrostatic biaxial MEMS micromirror structure

Abstract

The utility model relates to micro - nanometer technical field discloses a kind of vertical comb tooth electrostatic biaxial MEMS micro-mirror structure, comprising: first device structure layer, connecting layer, second device structure layer are stacked from bottom to top;First device structure layer includes first fixed comb tooth and second fixed comb tooth;Second device structure layer includes galvanometer frame and its two sides first torsion beam;First movable comb tooth is provided on first torsion beam;Galvanometer frame is annular;Galvanometer frame inside is provided with mirror body and its two sides second torsion beam;Second movable comb tooth is provided on second torsion beam;First torsion beam, galvanometer frame and second torsion beam are integral structure and electrically connected;First fixed comb tooth and first movable comb tooth are misaligned and correspond to set, second fixed comb tooth and second movable comb tooth are misaligned and correspond to set.The utility model can increase driving force and deflection angle, and then increase operating frequency and scanning angle, while reducing excitation response time.

Description

Technical Field

[0001] This utility model relates to the field of micro-nano technology, specifically to a vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure. Background Technology

[0002] In related technologies, the comb-tooth structure of planar comb-driven MEMS micromirror structures lies within a single plane and typically consists of alternating fixed and movable comb teeth. This structure extends planarly, making it easy to integrate with other planar MEMS devices. Its fabrication process is relatively simple and facilitates manufacturing using traditional planar micromachining techniques, making it a mainstream MEMS micromirror structure. However, because the comb teeth are in a plane, planar comb-driven structures are limited by the plane's dimensions, resulting in relatively small driving forces and difficulty in achieving large angles and displacements. At high frequencies, they may be affected by in-plane parasitic capacitance and resistance, leading to significant energy loss and performance degradation. Planar comb-tooth structures are gradually becoming unsuitable for applications requiring large-angle scanning, such as lidar systems, deformable mirrors in adaptive optics systems, and some microelectromechanical system sensors requiring large displacement actuation.

[0003] Vertical comb-driven systems can provide greater driving force and deflection angle. However, in current biaxial vertical comb micromirrors, the comb teeth are mostly fixed to the bottom surface. During Lissajous scanning, excessively large scanning angles can easily cause interference between the comb teeth. Furthermore, the electrical connections of vertical comb mirror structures are complex, making it difficult to precisely control the operation of the torsion beam and comb teeth, thus leading to higher fabrication difficulty and cost.

[0004] Therefore, a solution is needed to implement a biaxial micromirror that applies vertical comb teeth to the fast and slow axes, increasing the deflection angle, reducing interference between comb teeth, and simplifying the electrical connection structure between layers. Utility Model Content

[0005] In view of this, the present invention provides a vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure to solve the problems in related technologies, such as the small deflection angle of planar comb teeth, which makes it difficult to achieve large-angle and large-displacement driving, the complex electrical connection of vertical comb-tooth mirror structure, which makes it difficult to accurately control the movement of torsion beam and comb teeth, and the easy interference between comb teeth at large scanning angles.

[0006] In a first aspect, this utility model provides a vertical comb-tooth electrostatic biaxial MEMS micromirror structure, comprising: The first device structure layer, the connection layer, and the second device structure layer are stacked from bottom to top; The micro-mirror structure includes a mirror frame region distributed along a first direction and first driving regions on both sides in the vertical direction; the mirror frame region includes a mirror region distributed along a second direction and second driving regions on both sides; the first direction is perpendicular to the second direction. The first device structure layer includes a first fixed comb tooth located in the first driving region and a second fixed comb tooth located in the second driving region. The second device structure layer includes a galvanometer frame located in the galvanometer frame region and first torsion beams on both sides thereof; the first torsion beams are located in the first driving region; first movable comb teeth are provided on the first torsion beams; the galvanometer frame is annular; a reflector body located in the reflector region and second torsion beams on both sides thereof are provided inside the galvanometer frame; the second torsion beams are located in the second driving region; second movable comb teeth are provided on the second torsion beams; the first torsion beams, the galvanometer frame, and the second torsion beams are an integral structure and electrically connected; the first torsion beams are parallel to a first direction; the second torsion beams are parallel to a second direction; The first fixed comb tooth and the first movable comb tooth are offset and correspondingly arranged, and the first movable comb tooth is adapted to move along the first torsional direction between adjacent first fixed comb teeth; the second fixed comb tooth and the second movable comb tooth are offset and correspondingly arranged, and the second movable comb tooth is adapted to move along the second torsional direction between adjacent second fixed comb teeth.

[0007] The vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this utility model, on the one hand, sets a first fixed comb tooth and a second fixed comb tooth in the first device structure layer, and sets a first movable comb tooth and a second movable comb tooth in the second device structure layer; the first fixed comb tooth and the first movable comb tooth are staggered and corresponding to form a set of vertical comb teeth, and the second fixed comb tooth and the second movable comb tooth are staggered and corresponding to form another set of vertical comb teeth. By setting two sets of vertically driven vertical comb teeth, a vertical force can be provided for the mirror resonator, which is suitable for generating torsional isotropic motion, and can provide a large driving force and deflection angle, thereby realizing large-angle and large-displacement driving; at the same time, the large driving force can drive a torsion beam with higher stiffness, obtain a mirror with a higher operating frequency, and thus increase the scanning speed of the micromirror. On the other hand, the first torsion beam, the galvanometer frame, and the second torsion beam are integrated and electrically connected, which simplifies the electrical connection structure and improves the device integration. Simultaneously, when the first torsion beam undergoes torsional motion, the galvanometer frame and the second torsion beam move together, causing the second fixed comb teeth and the second movable comb teeth to move synchronously. This avoids collisions between the second fixed and movable comb teeth, improving the reliability and deflection angle of the micromirror. Therefore, the vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this invention can increase the driving force and deflection angle, thereby achieving a larger scanning angle and larger displacement. It can also increase the resonant frequency, thereby increasing the scanning speed and operating bandwidth of the micromirror, and further simplify the electrical connection structure, improving the device integration.

[0008] In one optional embodiment, the micromirror structure further includes: a metal electrode layer that penetrates the second device structure layer from the thickness direction; The metal electrode layer includes a first electrode, a second electrode, and a third electrode; the third electrode is connected to the first torsion beam; the first electrode and the second electrode penetrate the second device structure and are connected to the connection layer; The connecting layer is a sandwich structure consisting of a lower insulating layer, a conductive metal layer, and an upper insulating layer stacked from bottom to top; the upper insulating layer includes a first conductive hole and a second conductive hole connected to the conductive metal layer; the lower insulating layer includes a third conductive hole and a fourth conductive hole connected to the conductive metal layer; the conductive metal layer includes at least a first conductive block; the first conductive block is electrically isolated from the surrounding conductive metal layer. The first conductive hole and the third conductive hole are connected through the first conductive block; the first electrode is connected to the first fixed comb tooth through the first conductive hole, the first conductive block and the third conductive hole; the second conductive hole penetrates the upper insulating layer and connects to the second electrode, the fourth conductive hole penetrates the lower insulating layer and connects to the second fixed comb tooth, and the second conductive hole and the fourth conductive hole are connected through the conductive metal layer. The first electrode is adapted to provide a potential to the first fixed comb tooth, and the second electrode is adapted to provide a potential to the second fixed comb tooth; the first electrode is adapted to provide a potential to the first torsion beam, the galvanometer frame, and the second torsion beam; the first electrode is adapted to drive the first movable comb tooth to move; the second electrode is adapted to drive the second movable comb tooth to move; and the third electrode is adapted to drive the first movable comb tooth and the second movable comb tooth to move.

[0009] The vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this invention has the following advantages: First, by using a sandwich structure consisting of a lower insulating layer, a conductive metal layer, and an upper insulating layer as a connecting layer, precise potential control can be achieved for the first fixed comb tooth, the second fixed comb tooth, the first torsion beam, and the second torsion beam, simplifying the electrical connection structure between the structural layers and improving the integration of the device. Second, the first and second fixed comb teeth can be independently activated by different signals, providing a greater driving force for mirror deflection. Third, the first electrode is connected to the first fixed comb tooth through a first conductive hole, and the second electrode is connected to the second fixed comb tooth through a second and a third conductive hole. Through the vertical interconnection structure, the excitation and detection signals can be extracted from one side, facilitating subsequent packaging processes for the micromirror structure.

[0010] In one optional embodiment, the first device structure layer further includes a first substrate located in the first driving region and a second substrate located in the galvanometer frame region; a first fixed comb tooth is disposed on the side of the first substrate; a second fixed comb tooth is located on the side inside the second substrate; the second substrate corresponds vertically to the galvanometer frame. The second device structure layer also includes a device frame located in the first driving region; the device frame corresponds vertically to the first substrate. The connecting layer includes a first connecting portion located in the first driving region and a second connecting portion located in the galvanometer frame region; the first connecting portion has the same shape as the first substrate and corresponds vertically; the first connecting portion is fixedly connected to the first substrate and the device frame; the second connecting portion has the same shape as the second substrate and corresponds vertically; the second connecting portion is fixedly connected to the second substrate and the galvanometer frame. A metal electrode layer penetrates the device frame; the side of the third electrode is connected to the first torsion beam; the first electrode is connected to the first substrate and the first fixed comb teeth through the first conductive hole, the first conductive block and the third conductive hole; the second electrode is connected to the second substrate and the second fixed comb teeth through the second conductive hole, the conductive metal layer and the fourth conductive hole; the first conductive hole penetrates the upper insulating layer of the first connection part; the third conductive hole penetrates the lower insulating layer of the first connection part; the second conductive hole penetrates the upper insulating layer of the first connection part; the fourth conductive hole penetrates the lower insulating layer of the second connection part.

[0011] In one optional embodiment, the first substrate includes a first sub-sub ... The second substrate includes a third sub-sub ...

[0012] In one optional embodiment, the first movable comb tooth includes a first movable comb tooth and a second movable comb tooth, which are located on both sides of the first torsion beam respectively; the first comb tooth corresponds to and is staggered with the first movable comb tooth; the second comb tooth corresponds to and is staggered with the second movable comb tooth; the first movable comb tooth is adapted to move along a first torsion direction between adjacent first comb teeth; the second movable comb tooth is adapted to move along a first torsion direction between adjacent second comb teeth. The second movable comb tooth includes a third movable comb tooth and a fourth movable comb tooth, which are located on both sides of the second torsion beam respectively; the third comb tooth corresponds to and is staggered with the third movable comb tooth; the fourth comb tooth corresponds to and is staggered with the fourth movable comb tooth; the third movable comb tooth is adapted to move along the second torsion direction between adjacent third comb teeth; the fourth movable comb tooth is adapted to move along the second torsion direction between adjacent fourth comb teeth. The first and second comb teeth are symmetrically distributed along the first torsion beam; the third and fourth comb teeth are symmetrically distributed along the second torsion beam. The first and second moving comb teeth are symmetrically distributed along the first torsion beam; the third and fourth moving comb teeth are symmetrically distributed along the second torsion beam.

[0013] In one optional embodiment, the first electrode includes a first sub-electrode and a second sub-electrode; the first sub-electrode is connected to a first sub-substrate and a first comb tooth through a first conductive hole and a third conductive hole; the second sub-electrode is connected to a second sub-substrate and a second comb tooth through a first conductive hole and a third conductive hole; the first sub-electrode is adapted to provide a potential to the first comb tooth and drive the first moving comb tooth to move; the second sub-electrode is adapted to provide a potential to the second comb tooth and drive the second moving comb tooth to move. The second electrode includes a third sub-electrode and a fourth sub-electrode; the third sub-electrode is connected to the third sub-subbody and the third comb tooth through the second conductive hole and the fourth conductive hole; the fourth sub-electrode is connected to the fourth sub-subbody and the fourth comb tooth through the second conductive hole and the fourth conductive hole; the third sub-electrode is adapted to provide a potential to the third comb tooth and drive the third moving comb tooth to move; the fourth sub-electrode is adapted to provide a potential to the fourth comb tooth and drive the fourth moving comb tooth to move.

[0014] In one optional embodiment, the connecting layer further includes a third connecting portion that connects the first connecting portion and the second connecting portion, the third connecting portion being disposed corresponding to the first torsion beam; The first connection includes an electrically isolated first sub-connection and a second sub-connection, which are located on both sides of the second torsion beam, respectively; the conductive metal layers of the first sub-connection and the second sub-connection are spaced apart. The second connection includes an electrically isolated third sub-connection and a fourth sub-connection, which are located on both sides of the second torsion beam respectively; the first sub-connection and the third sub-connection are connected by the third connection; the second sub-connection and the fourth sub-connection are connected by the third connection. The first sub-electrode is located at the corresponding positions of the first sub-base and the first sub-connector. The first sub-electrode is connected to the first sub-base and the first comb tooth through the first conductive hole and the third conductive hole below it. The second sub-electrode is located at the corresponding position of the second sub-base and the second sub-connection part. The second sub-electrode is connected to the second sub-base and the second comb tooth through the first conductive hole and the third conductive hole below it. The third sub-electrode is located at the corresponding position of the second sub-base and the first sub-connector. The third sub-electrode is connected to the third sub-base and the third comb tooth through the second conductive hole in the first sub-connector and the fourth conductive hole in the third sub-connector. The fourth sub-electrode is located at the corresponding position of the first sub-base and the second sub-connector. The fourth sub-electrode is connected to the fourth sub-base and the fourth comb tooth through the second conductive hole in the second sub-connector and the fourth conductive hole in the fourth sub-connector.

[0015] The vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this utility model, by setting electrically isolated first and second sub-sub ...

[0016] In one optional embodiment, the lower insulating layer is a silicon dioxide layer; the upper insulating layer is a silicon dioxide layer; The conductive metal layer is made of gold; the first conductive hole, the second conductive hole, the third conductive hole, and the fourth conductive hole are all made of gold. The upper surface of the reflector is provided with a reflective mirror layer; the reflective mirror layer is made of metal. The material of the first device structure layer is conductive silicon; The material of the second device structure layer is conductive silicon; The metal electrode layer is located near the two edges of the second device structure layer; A dielectric layer or gap groove is provided between the side of the metal electrode layer and the second device structure layer, and the side of the metal electrode layer is electrically isolated from the interior of the second device structure layer. One side of the third electrode is electrically connected to the first torsion beam; the bottom of the first electrode is electrically connected to the first conductive hole; and the bottom of the second electrode is electrically connected to the second conductive hole.

[0017] In one optional embodiment, the first torsion beam includes a first intermediate torsion beam distributed along a second direction and first side torsion beams on both sides thereon; there is a first gap parallel to the first direction between the first intermediate torsion beam and the first side torsion beams; the first movable comb teeth are located on the side of the first side torsion beam facing away from the first intermediate torsion beam. The second torsion beam includes a second intermediate torsion beam distributed along the first direction and second side torsion beams on both sides; there is a second gap between the second intermediate torsion beam and the second side torsion beams parallel to the second direction; the second movable comb teeth are located on the side of the second side torsion beam facing away from the second intermediate torsion beam; The first intermediate torsion beam is connected to the third electrode; the second intermediate torsion beam is connected to the galvanometer frame.

[0018] In one optional embodiment, when the first movable comb tooth moves along the first torsion direction with the first torsion beam as the axis, the galvanometer frame and the internal reflector body and the second torsion beam follow the movement of the first movable comb tooth, and the second base and the second fixed comb tooth follow the movement of the galvanometer frame. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of this utility model, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a top view schematic diagram of a vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure according to an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the main structure of a vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure according to an embodiment of the present invention.

[0022] Figure 3 This is a schematic diagram of the first device structure layer of a vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure according to an embodiment of the present invention.

[0023] Figure 4 This is a schematic diagram of the second device structure layer of a vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure according to an embodiment of the present invention.

[0024] Figure 5 This is a schematic diagram of the upper insulating layer of a vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to an embodiment of the present invention.

[0025] Figure 6 This is a schematic diagram of the conductive metal layer of a vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to an embodiment of the present invention.

[0026] Figure 7 This is a schematic diagram of the lower insulating layer of a vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to an embodiment of the present invention.

[0027] Figure 8 According to an embodiment of this utility model, a vertical comb-tooth electrostatic biaxial MEMS micromirror structure is provided along... Figure 1 A schematic diagram of the cross-section of surface AA.

[0028] Figure 9 According to an embodiment of this utility model, a vertical comb-tooth electrostatic biaxial MEMS micromirror structure is provided along... Figure 1 A schematic diagram of the cross-section of the BB surface.

[0029] Figure 10According to an embodiment of this utility model, a vertical comb-tooth electrostatic biaxial MEMS micromirror structure is provided along... Figure 1 A cross-sectional diagram of the C-plane.

[0030] Figure 11 This is a schematic diagram of the second device structure layer of another vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure according to an embodiment of the present invention.

[0031] Figure label: 10. First device structure layer; 11. First fixed comb tooth; 12. Second fixed comb tooth; 13. First substrate; 14. Second substrate; 111. First comb tooth; 112. Second comb tooth; 121. Third comb tooth; 122. Fourth comb tooth; 131. First sub-substrate; 132. Second sub-substrate; 141. Third sub-substrate; 142. Fourth sub-substrate; 20. Second device structure layer; 21. First movable comb tooth; 22. Second movable comb tooth; 23. First torsion beam; 24. Second torsion beam; 25. Galvanometer frame; 26. Reflector body; 27. Device frame; 211. First movable comb tooth; 212. Second movable comb tooth; 221. Third movable comb tooth; 222. Fourth movable comb tooth; 261. Reflector surface layer; 30. Connecting layer; 301. Lower insulating layer; 302. Conductive metal layer; 303. Upper insulating layer; 31. First connecting part; 32. Second connecting part; 33. Third connecting part; 311. First sub-connecting part; 312. Second sub-connecting part; 321. Third sub-connecting part; 322. Fourth sub-connecting part; 310. First conductive block; 40. Metal electrode layer; 41. First electrode; 42. Second electrode; 43. Third electrode; 411. First sub-electrode; 412. Second sub-electrode; 421. Third sub-electrode; 422. Fourth sub-electrode; 51. First conductive hole; 52. Second conductive hole; 53. Third conductive hole; 54. Fourth conductive hole. Detailed Implementation

[0032] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0033] Currently, MEMS technology has made significant progress. It integrates microelectronics and micromachining technologies, enabling the miniaturization and integration of mechanical structures, sensors, and actuators onto a single chip. This technological advancement has laid the foundation for the emergence of MEMS micromirrors, making the manufacture of high-precision, high-performance micromirrors possible. With the widespread application of optical technology in communication, imaging, and sensing, higher demands are being placed on the miniaturization, integration, and intelligence of optical systems. MEMS micromirrors, with their small size, low power consumption, and fast response, have become an ideal choice to meet these needs.

[0034] In related technologies, the comb-tooth structure of planar comb-driven MEMS micromirror structures lies within a single plane and typically consists of alternating fixed and movable comb teeth. This structure extends planarly, making it easy to integrate with other planar MEMS devices. Its fabrication process is relatively simple and facilitates manufacturing using traditional planar micromachining techniques, making it a mainstream MEMS micromirror structure. However, because the comb teeth are in a plane, planar comb-driven structures are limited by the plane's dimensions, resulting in relatively small driving forces and difficulty in achieving large angles and displacements. At high frequencies, they may be affected by in-plane parasitic capacitance and resistance, leading to significant energy loss and performance degradation. Planar comb-tooth structures are gradually becoming unsuitable for applications requiring large-angle scanning, such as lidar systems, deformable mirrors in adaptive optics systems, and some microelectromechanical system sensors requiring large displacement actuation.

[0035] Vertical comb-driven systems can provide greater driving force and deflection angle. However, in current biaxial vertical comb micromirrors, the comb teeth are mostly fixed to the bottom surface. During Lissajous scanning, excessively large scanning angles can easily cause interference between the comb teeth. Furthermore, the electrical connections of vertical comb mirror structures are complex, making it difficult to precisely control the operation of the torsion beam and comb teeth, thus leading to higher fabrication difficulty and cost.

[0036] Therefore, a solution is needed to implement a biaxial micromirror that applies vertical comb teeth to the fast and slow axes, increasing the deflection angle, reducing interference between comb teeth, and simplifying the electrical connection structure between layers.

[0037] like Figure 1 and Figure 2 As shown, this embodiment provides a vertical comb-tooth electrostatic biaxial MEMS micromirror structure, including: The first device structure layer 10, the connection layer 30, and the second device structure layer 20 are stacked from bottom to top; The micro-mirror structure includes a mirror frame region distributed along a first direction and first driving regions on both sides in the vertical direction; the mirror frame region includes a mirror region distributed along a second direction and second driving regions on both sides; the first direction is perpendicular to the second direction. The first device structure layer 10 includes a first fixed comb tooth 11 located in the first driving region and a second fixed comb tooth 12 located in the second driving region. The second device structure layer 20 includes a galvanometer frame 25 located in the galvanometer frame region and first torsion beams 23 on both sides thereon; the first torsion beams 23 are located in the first driving region; first movable comb teeth 21 are provided on the first torsion beams 23; the galvanometer frame 25 is annular; a reflector body 26 located in the reflector region and second torsion beams 24 on both sides thereon are provided inside the galvanometer frame 25; the second torsion beams 24 are located in the second driving region; second movable comb teeth 22 are provided on the second torsion beams 24; the first torsion beams 23, the galvanometer frame 25 and the second torsion beams 24 are an integral structure and electrically connected; the first torsion beams 23 are parallel to the first direction; the second torsion beams 24 are parallel to the second direction; The first fixed comb tooth 11 and the first movable comb tooth 21 are offset and correspondingly arranged. The first movable comb tooth 21 is adapted to move along the first torsional direction between adjacent first fixed comb teeth 11. The second fixed comb tooth 12 and the second movable comb tooth 22 are offset and correspondingly arranged. The second movable comb tooth 22 is adapted to move along the second torsional direction between adjacent second fixed comb teeth 12.

[0038] In practice, the first torsion beam 23, the galvanometer frame 25, the second torsion beam 24, and the reflector body 26 are integrated into one structure.

[0039] The vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this utility model, on the one hand, sets a first fixed comb tooth and a second fixed comb tooth in the first device structure layer, and sets a first movable comb tooth and a second movable comb tooth in the second device structure layer; the first fixed comb tooth and the first movable comb tooth are staggered and corresponding to form a set of vertical comb teeth, and the second fixed comb tooth and the second movable comb tooth are staggered and corresponding to form another set of vertical comb teeth. By setting two sets of vertically driven vertical comb teeth, a vertical force can be provided for the mirror resonator, which is suitable for generating torsional isotropic motion, and can provide a large driving force and deflection angle, thereby realizing large-angle and large-displacement driving; at the same time, the large driving force can drive a torsion beam with higher stiffness, obtain a mirror with a higher operating frequency, and thus increase the scanning speed of the micromirror. On the other hand, the first torsion beam, the galvanometer frame, and the second torsion beam are integrated and electrically connected, which simplifies the electrical connection structure and improves the device integration. Simultaneously, when the first torsion beam undergoes torsional motion, the galvanometer frame and the second torsion beam move together with it, and the second fixed comb teeth and the second movable comb teeth also move synchronously, avoiding collisions and improving the reliability and deflection angle of the micromirror. Therefore, the vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this invention can increase the driving force and deflection angle, thereby achieving a larger scanning angle and larger displacement. It can also increase the resonant frequency, thereby increasing the scanning speed and operating bandwidth of the micromirror, and further simplify the electrical connection structure, improving the device integration.

[0040] In some alternative embodiments, the torsional frequency of the first torsion beam 23 is different from that of the second torsion beam 24.

[0041] In some alternative embodiments, the torsional frequency of the first torsion beam 23 is greater than the torsional frequency of the second torsion beam 24; The first torsion beam 23 is the fast axis, and the second torsion beam 24 is the slow axis; The first movable comb tooth 21 is a fast-axis movable comb tooth; the second movable comb tooth 22 is a slow-axis movable comb tooth; the first fixed comb tooth 11 is a fast-axis fixed comb tooth; and the second fixed comb tooth 12 is a slow-axis fixed comb tooth.

[0042] In some alternative implementations, such as Figure 1 As shown, the micromirror structure also includes: a metal electrode layer 40 that penetrates the second device structure layer 20 from the thickness direction; The metal electrode layer 40 includes a first electrode 41, a second electrode 42, and a third electrode 43; the third electrode 43 is connected to the first torsion beam 23; the first electrode 41 and the second electrode 42 penetrate the second device structure and are connected to the connection layer 30, such as... Figure 8 , Figure 9 and Figure 10 As shown; The connecting layer 30 is a sandwich structure consisting of a lower insulating layer 301, a conductive metal layer 302, and an upper insulating layer 303 stacked from bottom to top; the upper insulating layer 303 includes a first conductive hole 51 and a second conductive hole 52 connected to the conductive metal layer 302; the lower insulating layer 301 includes a third conductive hole 53 and a fourth conductive hole 54 connected to the conductive metal layer 302; the conductive metal layer 302 includes at least a first conductive block 310; the first conductive block 310 is electrically isolated from the surrounding conductive metal layer 302; The first conductive hole 51 and the third conductive hole 53 are connected by the first conductive block 310; the first electrode 41 is connected to the first fixed comb tooth 11 through the first conductive hole 51, the first conductive block 310 and the third conductive hole 53; the second conductive hole 52 penetrates the upper insulating layer 303 and connects to the second electrode 42; the fourth conductive hole 54 penetrates the lower insulating layer 301 and connects to the second fixed comb tooth 12; the second conductive hole 52 and the fourth conductive hole 54 are connected by the conductive metal layer 302. Wherein, the first electrode 41 is adapted to provide a potential to the first fixed comb tooth 11, and the second electrode 42 is adapted to provide a potential to the second fixed comb tooth 12; the first electrode 41 is adapted to provide a potential to the first torsion beam 23, the galvanometer frame 25, and the second torsion beam 24; the first electrode 41 is adapted to drive the first movable comb tooth 21 to move; the second electrode 42 is adapted to drive the second movable comb tooth 22 to move; and the third electrode 43 is adapted to drive the first movable comb tooth 21 and the second movable comb tooth 22 to move.

[0043] In some alternative implementations, such as Figure 6 As shown, an insulating region is provided on the side of the first conductive block 310 to electrically isolate the first conductive block 310 from the surrounding conductive metal layer 302. The insulating region can be a gap or a dielectric layer. In some embodiments, such as Figure 10 As shown, the first conductive hole 51, the first conductive block 310, and the third conductive hole 53 are all located directly below the first electrode 41.

[0044] The vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this utility model has the following advantages: First, by using a sandwich structure consisting of a lower insulating layer, a conductive metal layer, and an upper insulating layer as a connecting layer, precise potential control can be achieved for the first fixed comb tooth, the second fixed comb tooth, the first torsion beam, and the second torsion beam, simplifying the electrical connection structure between the structural layers and improving the integration of the device. Second, the first and second fixed comb teeth can be independently activated by different signals, providing a greater driving force for mirror deflection. Third, the first electrode is connected to the first fixed comb tooth through a first conductive hole, and the second electrode is connected to the second fixed comb tooth through a second and a third conductive hole. Through the vertical interconnection structure, the excitation and detection signals can be extracted from one side, facilitating subsequent packaging processes for the micromirror structure.

[0045] In some alternative implementations, such as Figure 3 As shown, the first device structure layer 10 also includes a first substrate 13 located in the first driving region and a second substrate 14 located in the galvanometer frame region; the first fixed comb teeth 11 are disposed on the side of the first substrate 13; the second fixed comb teeth 12 are located on the side of the inner side of the second substrate 14; the second substrate 14 corresponds vertically to the galvanometer frame 25. The second device structure layer 20 also includes a device frame 27 located in the first driving region; the device frame 27 corresponds vertically to the first substrate 13, such as... Figure 4 As shown; The connecting layer 30 includes a first connecting portion 31 located in the first driving region and a second connecting portion 32 located in the galvanometer frame region; the first connecting portion 31 has the same shape as the first substrate 13 and corresponds vertically; the first connecting portion 31 is fixedly connected to the first substrate 13 and the device frame 27; the second connecting portion 32 has the same shape as the second substrate 14 and corresponds vertically; the second connecting portion 32 is fixedly connected to the second substrate 14 and the galvanometer frame 25, such as... Figure 5 , Figure 6 and Figure 7 As shown; The metal electrode layer 40 penetrates the device frame 27, such as Figure 4 As shown; the side of the third electrode 43 is connected to the first torsion beam 23; the first electrode 41 is connected to the first substrate 13 and the first fixed comb tooth 11 through the first conductive hole 51, the first conductive block 310 and the third conductive hole 53; the second electrode 42 is connected to the second substrate 14 and the second fixed comb tooth 12 through the second conductive hole 52, the conductive metal layer and the fourth conductive hole 54; the first conductive hole 51 penetrates the upper insulating layer 303 of the first connecting part 31; the third conductive hole 53 penetrates the lower insulating layer 301 of the first connecting part 31; the second conductive hole 52 penetrates the upper insulating layer 303 of the first connecting part 31; the fourth conductive hole 54 penetrates the lower insulating layer 301 of the second connecting part 32, as shown. Figure 5 and Figure 7 As shown.

[0046] In specific implementation, such as Figure 1 and Figure 8 As shown, one side surface of the third electrode 43 is directly connected to the first torsion beam 23. (As indicated...) Figure 10 As shown, the first electrode 41 is connected to the corresponding first substrate 13 directly below it through the first conductive hole 51, the first conductive block 310, and the third conductive hole 53, and then connected to the first fixed comb tooth 11; the second electrode 42 is first connected to the conductive metal layer 302 through the second conductive hole 52, and then through the fourth conductive hole 54 (actually not in the CC section, indicated by a dashed line; the actual position of the fourth conductive hole 54 is referenced). Figure 7 ) is connected to the second substrate 14 directly below the galvanometer frame, and then to the second fixed comb tooth 12, as shown. Figure 3 As shown.

[0047] In some optional embodiments, the first substrate 13 includes a first sub-sub ... The second substrate 14 includes a third sub-sub ...

[0048] In some optional embodiments, the first movable comb tooth 21 includes a first movable comb tooth 211 and a second movable comb tooth 212, respectively located on both sides of the first torsion beam 23; the first comb tooth 111 corresponds to and is staggered with the first movable comb tooth 211; the second comb tooth 112 corresponds to and is staggered with the second movable comb tooth 212; the first movable comb tooth 211 is adapted to move along a first torsion direction between adjacent first comb teeth 111; the second movable comb tooth 212 is adapted to move along a first torsion direction between adjacent second comb teeth 112. The second movable comb tooth 22 includes a third movable comb tooth 221 and a fourth movable comb tooth 222, which are located on both sides of the second torsion beam 24, respectively; the third comb tooth 121 corresponds to and is staggered with the third movable comb tooth 221; the fourth comb tooth 122 corresponds to and is staggered with the fourth movable comb tooth 222; the third movable comb tooth 221 is adapted to move along the second torsion direction between adjacent third comb teeth 121; the fourth movable comb tooth 222 is adapted to move along the second torsion direction between adjacent fourth comb teeth 122. The first comb tooth 111 and the second comb tooth 112 are symmetrically distributed along the first torsion beam 23; the third comb tooth 121 and the fourth comb tooth 122 are symmetrically distributed along the second torsion beam 24. The first moving comb tooth 211 and the second moving comb tooth 212 are symmetrically distributed along the first torsion beam 23; the third moving comb tooth 221 and the fourth moving comb tooth 222 are symmetrically distributed along the second torsion beam 24.

[0049] In some alternative implementations, such as Figure 4As shown, the first electrode 41 includes a first sub-electrode 411 and a second sub-electrode 412; the first sub-electrode 411 is connected to the first sub-substrate 131 and the first comb tooth 111 through a first conductive hole 51 and a third conductive hole 53; the second sub-electrode 412 is connected to the second sub-substrate 132 and the second comb tooth 112 through the first conductive hole 51 and the third conductive hole 53; the first sub-electrode 411 is adapted to provide a potential to the first comb tooth 111 and drive the first movable comb tooth 211 to move; the second sub-electrode 412 is adapted to provide a potential to the second comb tooth 112 and drive the second movable comb tooth 212 to move. The second electrode 42 includes a third sub-electrode 421 and a fourth sub-electrode 422; the third sub-electrode 421 is connected to the third sub-subbase 141 and the third comb tooth 121 through the second conductive hole 52 and the fourth conductive hole 54; the fourth sub-electrode 422 is connected to the fourth sub-subbase 142 and the fourth comb tooth 122 through the second conductive hole 52 and the fourth conductive hole 54; the third sub-electrode 421 is adapted to provide a potential to the third comb tooth 121 and drive the third moving comb tooth 221 to move; the fourth sub-electrode 422 is adapted to provide a potential to the fourth comb tooth 122 and drive the fourth moving comb tooth 222 to move.

[0050] In some optional embodiments, the connecting layer 30 further includes a third connecting portion 33 that connects the first connecting portion 31 and the second connecting portion 32, and the third connecting portion 33 is disposed corresponding to the first torsion beam 23; The first connection portion 31 includes an electrically isolated first sub-connection portion 311 and a second sub-connection portion 312, which are located on both sides of the second torsion beam 24, respectively; the conductive metal layers 302 of the first sub-connection portion 311 and the second sub-connection portion 312 are spaced apart. The second connecting part 32 includes an electrically isolated third sub-connecting part 321 and a fourth sub-connecting part 322, which are located on both sides of the second torsion beam 24 respectively; the first sub-connecting part 311 and the third sub-connecting part 321 are connected by the third connecting part 33; the second sub-connecting part 312 and the fourth sub-connecting part 322 are connected by the third connecting part 33. The first sub-electrode 411 is located at the corresponding positions of the first sub-base 131 and the first sub-connection portion 311. The first sub-electrode 411 is connected to the first sub-base 131 and the first comb tooth 111 through the first conductive hole 51 and the third conductive hole 53 below it. The second sub-electrode 412 is located at the corresponding position of the second sub-base 132 and the second sub-connection portion 312. The second sub-electrode 412 is connected to the second sub-base 132 and the second comb tooth 112 through the first conductive hole 51 and the third conductive hole 53 below it. The third sub-electrode 421 is located at the corresponding positions of the second sub-base 132 and the first sub-connection portion 311. The third sub-electrode 421 is connected to the third sub-base 141 and the third comb tooth 121 through the second conductive hole 52 in the first sub-connection portion 311 and the fourth conductive hole 54 in the third sub-connection portion 321. The fourth sub-electrode 422 is located at the corresponding position of the first sub-base 131 and the second sub-connection portion 312. The fourth sub-electrode 422 is connected to the fourth sub-base 142 and the fourth comb tooth 122 through the second conductive hole 52 in the second sub-connection portion 312 and the fourth conductive hole 54 in the fourth sub-connection portion 322.

[0051] The vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this utility model, by setting electrically isolated first and second sub-sub ...

[0052] In some alternative embodiments, the lower insulating layer 301 is a silicon dioxide layer; the upper insulating layer 303 is a silicon dioxide layer; The conductive metal layer 302 is made of gold; the first conductive hole 51, the second conductive hole 52, the third conductive hole 53 and the fourth conductive hole 54 are all made of gold. The upper surface of the reflector body 26 is provided with a reflector surface layer 261; the material of the reflector surface layer 261 is metal; The material of the first device structure layer 10 is conductive silicon; The material of the second device structure layer 20 is conductive silicon.

[0053] In some alternative embodiments, the metal electrode layer 40 is located near the two side edges of the second device structure layer 20; A dielectric layer or gap trench (not shown in the figure) is provided between the side of the metal electrode layer 40 and the second device structure layer 20, and the side of the metal electrode layer 40 is electrically isolated from the interior of the second device structure layer 20. One side of the third electrode 43 is electrically connected to the first torsion beam 23; the bottom of the first electrode 41 is electrically connected to the first conductive hole 51; and the bottom of the second electrode 42 is electrically connected to the second conductive hole 52.

[0054] In some alternative embodiments, the metal electrode layer 40 extends through the device frame 27; the metal electrode layer 40 is located near the two side edges of the device frame 27.

[0055] In some alternative implementations, such as Figure 11 As shown, the first torsion beam 23 includes a first intermediate torsion beam 230 distributed along the second direction and first side torsion beams 231 on both sides; there is a first gap parallel to the first direction between the first intermediate torsion beam 230 and the first side torsion beams 231; the first movable comb tooth 21 is located on the side of the first side torsion beam 231 facing away from the first intermediate torsion beam 230. The second torsion beam 24 includes a second intermediate torsion beam 240 distributed along a first direction and second side torsion beams 241 on both sides; there is a second gap parallel to the second direction between the second intermediate torsion beam 240 and the second side torsion beams 241; the second movable comb tooth 22 is located on the side of the second side torsion beam 241 facing away from the second intermediate torsion beam 240. The first intermediate torsion beam 230 is connected to the third electrode 43; the second intermediate torsion beam 240 is connected to the galvanometer frame 25.

[0056] In specific implementation, such as Figure 11 As shown, the first intermediate torsion beam 230 and the first side torsion beam 231 are parallel and each has one end connected to the galvanometer frame 25; the other end of the first intermediate torsion beam 230 is connected to the third electrode 43; the first side torsion beam 231 is not connected to any other structure. The second intermediate torsion beam 240 and the second side torsion beam 241 are parallel and each has one end connected to the mirror body; the other end of the second intermediate torsion beam 240 is connected to the galvanometer frame 25; the second end of the second side torsion beam 241 is not connected to any other structure.

[0057] When the micromirror is working, the first intermediate torsion beam 230 serves as the torsion axis, and the first movable comb tooth 21 and the first side torsion beam 231 move together about the first intermediate torsion beam 230 along the first torsion direction. The second intermediate torsion beam 240 serves as the torsion axis, and the second movable comb tooth 22 and the second side torsion beam 241 move together about the second intermediate torsion beam 240 along the second torsion direction.

[0058] In some alternative embodiments, when the first movable comb tooth 21 moves along the first torsion direction with the first torsion beam 23 as the axis, the galvanometer frame 25 and its internal reflector body 26 and the second torsion beam 24 move with the first movable comb tooth 21, and the second base 14 and the second fixed comb tooth 12 move with the galvanometer frame 25.

[0059] The vertical comb-tooth electrostatic biaxial MEMS micromirror structure provided by this utility model has an integral structure consisting of a first torsion beam, a mirror frame, a second torsion beam, and a reflector body. Furthermore, the second connecting part is fixedly connected to the second substrate and the mirror frame. Therefore, when the first movable comb tooth moves along the first torsion direction with the first torsion beam as the axis, the mirror frame and its internal reflector body and the second torsion beam move with the first movable comb tooth. The second substrate and the second fixed comb tooth also move synchronously with the mirror frame. This makes the movement of the second movable comb tooth and the relative stillness of the second fixed comb tooth relatively stable, which can prevent the movement of the second movable comb tooth and the second fixed comb tooth from colliding, thereby improving the reliability and accuracy of the micromirror.

[0060] In some optional embodiments, when the first movable comb tooth 21 is twisted about the first torsion beam along the first torsion direction, if the first movable comb tooth 211 moves downward, the second movable comb tooth 212 moves upward; if the first movable comb tooth 211 moves upward, the second movable comb tooth 212 moves downward. When the second movable comb tooth 22 is twisted along the second torsion direction with the first torsion beam as the axis, if the third movable comb tooth 221 moves downward, then the fourth movable comb tooth 222 moves upward; if the third movable comb tooth 221 moves upward, then the fourth movable comb tooth 222 moves downward.

[0061] In some alternative embodiments, the thickness of the first substrate 13 is greater than the thickness of the second substrate 14; the first device structure layer 10 also includes a downwardly opening groove; the groove is located in the second substrate 14; The first substrate 13 can serve as the support for the entire micromirror structure. The groove can provide space for the first movable comb tooth 21 when it is along the first torsion direction with the first torsion beam 23 as the axis, and provide space for the second movable comb tooth 22 when it is along the second torsion direction with the second torsion beam 24 as the axis.

[0062] The vertical comb-tooth electrostatic biaxial MEMS micro-mirror structure provided by this utility model, by setting the thickness of the first substrate to be greater than the thickness of the second substrate, can form a groove under the two sets of vertical comb tooth structures and the mirror frame, providing sufficient space for the torsional movement of the first movable comb tooth and the second movable comb tooth. At the same time, it can provide sufficient space for the overall structure of the second torsion beam, the mirror body, the second substrate and the second fixed comb tooth to follow the movement of the first torsion beam, which can ensure that the micro-mirror structure can achieve a large deflection angle, while improving the stability and reliability of the device.

[0063] In some alternative embodiments, the torsional frequency of the first torsion beam 23 is greater than the torsional frequency of the second torsion beam 24; The first torsion beam 23 is the fast axis, and the second torsion beam 24 is the slow axis; The first movable comb tooth 21 is a fast-axis movable comb tooth; the second movable comb tooth 22 is a slow-axis movable comb tooth; the first fixed comb tooth 11 is a fast-axis fixed comb tooth; and the second fixed comb tooth 12 is a slow-axis fixed comb tooth.

[0064] In the description of this specification, the terms "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0065] The above description does not provide detailed explanations of the technical aspects of each layer's patterning, etching, etc. However, those skilled in the art should understand that various technical means can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.

[0066] The above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described above, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention. The protection scope of the present invention is determined by the scope of the appended claims.

Claims

1. A vertical comb-tooth electrostatic biaxial MEMS micromirror structure, characterized in that, include: The first device structure layer, the connection layer, and the second device structure layer are stacked from bottom to top; The micro-mirror structure includes a mirror frame region distributed along a first direction and first driving regions on both sides in the vertical direction; the mirror frame region includes a mirror region distributed along a second direction and second driving regions on both sides; the first direction is perpendicular to the second direction. The first device structure layer includes a first fixed comb tooth located in the first driving region and a second fixed comb tooth located in the second driving region; The second device structure layer includes a galvanometer frame located in the galvanometer frame region and first torsion beams on both sides thereof; the first torsion beams are located in the first driving region; the first torsion beams are provided with first movable comb teeth; the galvanometer frame is annular; a reflector body located in the reflector region and second torsion beams on both sides thereof are provided inside the galvanometer frame; the second torsion beams are located in the second driving region; the second torsion beams are provided with second movable comb teeth; the first torsion beams, the galvanometer frame, and the second torsion beams are an integral structure and electrically connected; the first torsion beams are parallel to a first direction; the second torsion beams are parallel to a second direction; The first fixed comb tooth and the first movable comb tooth are offset and correspondingly arranged, and the first movable comb tooth is adapted to move along a first torsional direction between adjacent first fixed comb teeth; the second fixed comb tooth and the second movable comb tooth are offset and correspondingly arranged, and the second movable comb tooth is adapted to move along a second torsional direction between adjacent second fixed comb teeth.

2. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 1, characterized in that, The micromirror structure further includes: a metal electrode layer that penetrates the second device structure layer from the thickness direction; The metal electrode layer includes a first electrode, a second electrode, and a third electrode; the third electrode is connected to the first torsion beam; the first electrode and the second electrode penetrate the second device structure and are connected to the connection layer; The connecting layer is a sandwich structure consisting of a lower insulating layer, a conductive metal layer, and an upper insulating layer stacked from bottom to top; the upper insulating layer includes a first conductive hole and a second conductive hole connected to the conductive metal layer; the lower insulating layer includes a third conductive hole and a fourth conductive hole connected to the conductive metal layer; the conductive metal layer includes at least a first conductive block; the first conductive block is electrically isolated from the surrounding conductive metal layer; The first conductive hole and the third conductive hole are connected through the first conductive block; the first electrode is connected to the first fixed comb tooth through the first conductive hole, the first conductive block and the third conductive hole; the second conductive hole penetrates the upper insulating layer and connects to the second electrode, the fourth conductive hole penetrates the lower insulating layer and connects to the second fixed comb tooth, and the second conductive hole and the fourth conductive hole are connected through a conductive metal layer; Wherein, the first electrode is adapted to provide a potential to the first fixed comb tooth, and the second electrode is adapted to provide a potential to the second fixed comb tooth; the first electrode is adapted to provide a potential to the first torsion beam, the galvanometer frame, and the second torsion beam; the first electrode is adapted to drive the first movable comb tooth to move; the second electrode is adapted to drive the second movable comb tooth to move; and the third electrode is adapted to drive the first movable comb tooth and the second movable comb tooth to move.

3. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 2, characterized in that, The first device structure layer further includes a first substrate located in the first driving region and a second substrate located in the galvanometer frame region; the first fixed comb teeth are disposed on the side of the first substrate; the second fixed comb teeth are located on the side inside the second substrate; the second substrate corresponds vertically to the galvanometer frame. The second device structure layer also includes a device frame located in the first driving region; the device frame corresponds vertically to the first substrate; The connecting layer includes a first connecting portion located in the first driving region and a second connecting portion located in the galvanometer frame region; the first connecting portion has the same shape as the first substrate and is vertically corresponding; the first connecting portion is fixedly connected to the first substrate and the device frame; the second connecting portion has the same shape as the second substrate and is vertically corresponding; the second connecting portion is fixedly connected to the second substrate and the galvanometer frame. The metal electrode layer penetrates the device frame; the side of the third electrode is connected to the first torsion beam; the first electrode is connected to the first substrate and the first fixed comb teeth through the first conductive hole, the first conductive block and the third conductive hole; the second electrode is connected to the second substrate and the second fixed comb teeth through the second conductive hole, the conductive metal layer and the fourth conductive hole; the first conductive hole penetrates the upper insulating layer of the first connecting part; the third conductive hole penetrates the lower insulating layer of the first connecting part; the second conductive hole penetrates the upper insulating layer of the first connecting part; the fourth conductive hole penetrates the lower insulating layer of the second connecting part.

4. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 3, characterized in that, The first substrate includes a first sub-sub ... The second substrate includes a third sub-sub ...

5. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 4, characterized in that, The first movable comb tooth includes a first movable comb tooth and a second movable comb tooth, which are located on both sides of the first torsion beam respectively; the first comb tooth corresponds to and is staggered with the first movable comb tooth; the second comb tooth corresponds to and is staggered with the second movable comb tooth; the first movable comb tooth is adapted to move along a first torsion direction between adjacent first comb teeth; the second movable comb tooth is adapted to move along a first torsion direction between adjacent second comb teeth. The second movable comb tooth includes a third movable comb tooth and a fourth movable comb tooth, which are located on both sides of the second torsion beam respectively; the third comb tooth corresponds to and is staggered with the third movable comb tooth; the fourth comb tooth corresponds to and is staggered with the fourth movable comb tooth; the third movable comb tooth is adapted to move along the second torsion direction between adjacent third comb teeth; the fourth movable comb tooth is adapted to move along the second torsion direction between adjacent fourth comb teeth. The first comb teeth and the second comb teeth are symmetrically distributed along the first torsion beam; the third comb teeth and the fourth comb teeth are symmetrically distributed along the second torsion beam; The first and second moving comb teeth are symmetrically distributed along the first torsion beam; the third and fourth moving comb teeth are symmetrically distributed along the second torsion beam.

6. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 5, characterized in that, The first electrode includes a first sub-electrode and a second sub-electrode; the first sub-electrode is connected to a first sub-sub-base and a first comb tooth through a first conductive hole and a third conductive hole; the second sub-electrode is connected to a second sub-sub-base and a second comb tooth through a first conductive hole and a third conductive hole; the first sub-electrode is adapted to provide a potential to the first comb tooth and drive the first moving comb tooth to move; the second sub-electrode is adapted to provide a potential to the second comb tooth and drive the second moving comb tooth to move. The second electrode includes a third sub-electrode and a fourth sub-electrode; the third sub-electrode is connected to the third sub-sub-base and the third comb tooth through the second conductive hole and the fourth conductive hole; the fourth sub-electrode is connected to the fourth sub-sub-base and the fourth comb tooth through the second conductive hole and the fourth conductive hole; the third sub-electrode is adapted to provide a potential to the third comb tooth and drive the third moving comb tooth to move; the fourth sub-electrode is adapted to provide a potential to the fourth comb tooth and drive the fourth moving comb tooth to move.

7. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 6, characterized in that, The connecting layer further includes a third connecting portion that connects the first connecting portion and the second connecting portion, and the third connecting portion is disposed corresponding to the first torsion beam; The first connection portion includes an electrically isolated first sub-connection portion and a second sub-connection portion, which are located on both sides of the second torsion beam, respectively; the conductive metal layers of the first sub-connection portion and the second sub-connection portion are spaced apart. The second connection part includes an electrically isolated third sub-connection part and a fourth sub-connection part, which are located on both sides of the second torsion beam respectively; the first sub-connection part and the third sub-connection part are connected by the third connection part; the second sub-connection part and the fourth sub-connection part are connected by the third connection part. The first sub-electrode is located at the corresponding positions of the first sub-base and the first sub-connector. The first sub-electrode is connected to the first sub-base and the first comb tooth through the first conductive hole and the third conductive hole below it. The second sub-electrode is located at the corresponding position of the second sub-base and the second sub-connector. The second sub-electrode is connected to the second sub-base and the second comb tooth through the first conductive hole and the third conductive hole below it. The third sub-electrode is located at the corresponding positions of the second sub-base and the first sub-connector. The third sub-electrode is connected to the third sub-base and the third comb tooth through the second conductive hole in the first sub-connector and the fourth conductive hole in the third sub-connector. The fourth sub-electrode is located at the corresponding position of the first sub-base and the second sub-connector. The fourth sub-electrode is connected to the fourth sub-base and the fourth comb tooth through the second conductive hole in the second sub-connector and the fourth conductive hole in the fourth sub-connector.

8. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 2, characterized in that, The lower insulating layer is a silicon dioxide layer; the upper insulating layer is a silicon dioxide layer; The conductive metal layer is made of gold; the first conductive hole, the second conductive hole, the third conductive hole, and the fourth conductive hole are all made of gold. The upper surface of the reflector is provided with a reflector surface layer; the material of the reflector surface layer is metal. The material of the first device structure layer is conductive silicon; The material of the second device structure layer is conductive silicon; The metal electrode layer is located near the two side edges of the second device structure layer; A dielectric layer or gap groove is provided between the side of the metal electrode layer and the second device structure layer, and the side of the metal electrode layer is electrically isolated from the interior of the second device structure layer. One side of the third electrode is electrically connected to the first torsion beam; the bottom of the first electrode is electrically connected to the first conductive hole; and the bottom of the second electrode is electrically connected to the second conductive hole.

9. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 2, characterized in that, The first torsion beam includes a first intermediate torsion beam distributed along a second direction and first side torsion beams on both sides; there is a first gap between the first intermediate torsion beam and the first side torsion beams parallel to the first direction; the first movable comb teeth are located on the side of the first side torsion beam facing away from the first intermediate torsion beam; The second torsion beam includes a second intermediate torsion beam distributed along a first direction and second side torsion beams on both sides; there is a second gap between the second intermediate torsion beam and the second side torsion beams parallel to the second direction; the second movable comb tooth is located on the side of the second side torsion beam opposite to the second intermediate torsion beam; The first intermediate torsion beam is connected to the third electrode; the second intermediate torsion beam is connected to the galvanometer frame.

10. The vertical comb-tooth electrostatic biaxial MEMS micromirror structure according to claim 5, characterized in that, When the first movable comb tooth moves along the first torsion direction with the first torsion beam as the axis, the galvanometer frame and the internal mirror body and the second torsion beam follow the movement of the first movable comb tooth, and the second base and the second fixed comb tooth follow the movement of the galvanometer frame.

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