Two-dimensional electrostatic scanning micromirror

Abstract

This invention discloses a two-dimensional electrostatic scanning micromirror, comprising an outer frame, an inner frame, and a mirror surface. The outer frame is machined with an outer frame isolation groove, dividing it into an outer frame measurement section, an outer frame driving section, and two outer frame connecting sections. An external feedback comb group is located between the outer frame measurement section and the inner frame, and an external driving comb group is located between the outer frame driving section and the inner frame. The mirror surface is machined with a mirror surface isolation groove, dividing it into a mirror surface feedback section, a mirror surface driving section, and a central section. An internal feedback comb group and an internal driving comb group are machined between the mirror surface feedback section and the inner frame, respectively. By setting isolation grooves with different structures on the outer frame and the mirror surface, the outer frame and the mirror surface are separated into different functional parts. The inner and outer comb groups are respectively set as driving comb groups and feedback comb groups, enabling the measurement of the mirror surface deflection angle in two directions. Real-time feedback of the mirror surface deflection angle in different directions can be achieved, improving the accuracy of mirror surface deflection angle control.

Description

Technical Field

[0001] This invention relates to the field of microelectromechanical systems (MEMS), and in particular to a two-dimensional electrostatic scanning micromirror fabricated using MEMS technology that can provide real-time angle feedback. Background Technology

[0002] MEMS stands for Micro-Electro-Mechanical System, a revolutionary new technology developed based on microelectronics. It integrates photolithography, etching, thin film processing, silicon micromachining, and precision machining to create high-tech electromechanical devices. MEMS devices are widely used in high-tech industries and are a key technology related to technological development, economic prosperity, and national defense security. Among them, scanning micromirrors are light-reflecting devices developed using MEMS technology. Through a torsional structure connecting the reflective mirror, the mirror is deflected under micro-driving force, achieving one-dimensional or two-dimensional reflection scanning of light beams. They have advantages such as low cost, high reliability, miniaturization, and easy mass production, and have a huge application market in fields such as optical communication, laser projection, lidar, and 3D imaging. When light is reflected by a micromirror, the mirror deflection angle needs to be monitored in real time. For electrostatically driven micromirrors, the electrostatic force between the comb teeth causes relative torsion, leading to a change in the capacitance between the comb teeth. By detecting the capacitance value between the comb teeth, the real-time deflection angle of the mirror can be obtained. For example, Chinese patent ZL201110191626.1—A torsional micromirror with a grooved isolation surface and its manufacturing method—targets a single-axis micromirror. By dividing the mirror surface into two regions to distinguish between the driving signal and the detection signal, it prevents signal superposition from affecting capacitance detection and achieves real-time measurement and feedback of the mirror deflection angle. A biaxial electrostatic micromirror, composed of inner and outer frames, two sets of mutually perpendicular torsional beams, and a mirror surface, allows the mirror surface to deflect simultaneously in two mutually perpendicular directions, achieving two-dimensional scanning of the light source. However, existing technologies cannot simultaneously measure the deflection angle of a two-dimensional electrostatic scanning micromirror in two directions, resulting in ineffective feedback and precise control of the mirror deflection angle in practical applications. Summary of the Invention

[0003] To address the problem in existing technologies that cannot monitor the deflection angle of a two-dimensional scanning micromirror in two directions in real time, the applicant provides a novel two-dimensional electrostatic scanning micromirror that can measure the capacitance changes of the inner and outer sets of feedback combs in real time, thereby obtaining the deflection angle of the mirror in two directions and enabling precise control of the mirror's deflection state.

[0004] The technical solution adopted in this invention is as follows:

[0005] A two-dimensional electrostatic scanning micromirror includes an outer frame, an inner frame, and a mirror surface. The outer frame and the inner frame are connected by an outer torsion beam, and the inner frame and the mirror surface are connected by an inner torsion beam. The directions of the inner torsion beam and the outer torsion beam are perpendicular to each other. An outer frame isolation groove is machined on the outer frame to divide the outer frame into an outer frame measuring part, an outer frame driving part, and two outer frame connecting parts. An outer feedback comb tooth group is provided between the outer frame measuring part and the inner frame, and an outer drive comb tooth group is provided between the outer frame driving part and the inner frame.

[0006] As a further improvement to the above technical solution:

[0007] The mirror surface is machined with a mirror isolation groove, dividing the mirror surface into a mirror feedback section, a mirror drive section, and a central section; the mirror feedback section and the mirror drive section are respectively machined with an inner feedback comb tooth group and an inner drive comb tooth group between them and the inner frame; the surface of the micromirror has an insulating layer, on which are machined inner drive wires and electrodes and inner feedback wires and electrodes, with the electrodes located at the outer frame connection section, and the ends of the inner drive wires and electrodes connected to the mirror drive section; the ends of the inner feedback wires and electrodes are connected to the mirror feedback section.

[0008] The outer frame measuring section and the outer frame driving section are respectively machined with a first electrode and a second electrode.

[0009] The inner drive wire and electrode wires pass sequentially through the outer frame connecting part, outer torsion beam, inner frame, inner torsion beam, and central surface, with their ends connected to the mirror drive part; the inner feedback wire and electrode wires pass through the outer frame connecting part, outer torsion beam, inner frame, inner torsion beam, and central surface, with their ends connected to the mirror feedback part.

[0010] The outer frame connecting part, inner frame, mirror, outer torsion beam and inner torsion beam surfaces are covered with an insulating layer.

[0011] The outer frame connecting part is provided with a third electrode that is in communication with the micromirror silicon substrate; the isolation groove on the mirror surface is located at the edge of the mirror surface near the comb teeth.

[0012] The outer frame has four outer frame isolation grooves; the mirror surface has two symmetrical mirror isolation grooves.

[0013] The outer frame isolation groove is located at the position of the stationary tooth on one side of the outer frame, dividing one side of the outer frame into an outer frame measuring part and an outer frame driving part; the stationary tooth on the inner side of the outer frame measuring part and the moving tooth corresponding to the inner frame form an external feedback comb tooth group, and the stationary tooth on the inner side of the outer frame driving part and the moving tooth corresponding to the inner frame form an external driving comb tooth group.

[0014] The mirror isolation groove consists of two parallel straight lines.

[0015] The mirror isolation groove on one side of the mirror divides the mirror into a mirror driving section and a central section; the mirror isolation groove on the other side divides one side of the mirror into a mirror driving section and a mirror feedback section. The moving teeth connected to the mirror driving section and the corresponding stationary teeth of the inner frame form an inner driving comb group, and the moving teeth connected to the mirror feedback section and the corresponding stationary teeth of the inner frame form an inner feedback comb group. The portion of the inner driving wire and electrode on the mirror surface is T-shaped and simultaneously connected to the mirror driving sections on both sides of the mirror to provide driving signals.

[0016] The mirror isolation groove on at least one side is T-shaped.

[0017] The mirror isolation groove on at least one side is double-T shaped.

[0018] The mirror-like isolation groove has a broken line structure or a curved structure.

[0019] The mirror surface is square, circular, or elliptical in shape; the outer torsion beam and the inner torsion beam are straight beams, folded beams, or other connecting structures.

[0020] The outer frame isolation groove and the mirror isolation groove are filled with insulating material.

[0021] The beneficial effects of this invention are as follows:

[0022] The two-dimensional electrostatic scanning micromirror of the present invention separates the outer frame and the mirror surface into different functional areas by setting isolation grooves with different structures on the outer frame and the mirror surface. Then, through specially shaped metal wires and electrodes, the inner and outer comb teeth are respectively set as driving comb tooth groups and feedback comb tooth groups, which can realize real-time measurement of the deflection angle of the mirror surface in two directions. Compared with the prior art, it can provide real-time feedback on the deflection angle of the mirror surface in different directions and improve the accuracy of mirror deflection angle control.

[0023] All the isolation grooves in this invention are located on the outer frame and the mirror surface, eliminating the need to set isolation grooves on the narrow torsion beam and inner frame. The isolation grooves are filled with insulating material to serve as isolation, while effectively fixing different parts together. This effectively reduces stress and stiffness problems caused by the introduction of other insulating materials, thereby improving the reliability of the micromirror. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention.

[0025] Figure 2 for Figure 1 A schematic diagram of the structure of the central mirror section.

[0026] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the present invention.

[0027] Figure 4 This is an enlarged view of part A in Figure 3.

[0028] Figure 5 This is an enlarged view of part B in Figure 3.

[0029] Figure 6 This is a schematic diagram of the inner frame and mirror surface in Embodiment 3 of the present invention.

[0030] Figure 7 This is a schematic diagram of one structure of the isolation groove of the present invention.

[0031] Figure 8 This is a schematic diagram of another structure of the isolation groove of the present invention.

[0032] Figures 9A-9D This is a schematic diagram illustrating the steps involved in fabricating the scanning micromirror of this invention.

[0033] In the figure: 1. Outer frame; 1-1. Outer frame measuring part; 1-2. Outer frame driving part; 1-3. Outer frame connecting part; 2. Inner frame; 3. Mirror; 3-1. Mirror feedback part; 3-2. Mirror driving part; 3-3. Center part; 4. Outer torsion beam; 5. Inner torsion beam; 6. Outer frame isolation groove; 7-1. Outer feedback comb tooth group; 7-2. Outer driving comb tooth group; 8. Mirror isolation groove; 9-1. Inner feedback comb tooth group; 9-2. Inner driving comb tooth group; 10. First electrode; 11. Second electrode; 12. Third electrode; 13. Inner driving wire and electrode; 14. Inner feedback wire and electrode; 21. Photoresist; 22. SOI silicon wafer; 23. Insulating material; 24. Metal. Detailed Implementation

[0034] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0035] Example 1:

[0036] like Figure 1 and Figure 2 As shown, the two-dimensional electrostatic scanning micromirror of the present invention, based on silicon material, includes an outer frame 1, an inner frame 2, and a mirror 3, the mirror 3 being square. The outer frame 1 and the inner frame 2 are connected together by two outer torsion beams 4, and the inner frame 2 and the mirror 3 are connected together by two inner torsion beams 5, the inner torsion beams 5 and the outer torsion beams 4 being perpendicular in direction. The mirror 3 can be deflected about the inner torsion beams 5 as axes, and the inner frame 2 and the mirror 3 can be deflected about the outer torsion beams 4 as axes, thereby achieving deflection of the mirror 3 in two perpendicular directions.

[0037] Four outer frame isolation grooves 6 are machined on the outer frame 1, dividing the outer frame 1 into an outer frame measuring section 1-1, an outer frame driving section 1-2, and an outer frame connecting section 1-3. These three parts are electrically isolated and do not conduct electricity to each other. Between the outer frame 1 and the inner frame 2, where there is no torsion beam, there are external feedback comb teeth 7-1 and external driving comb teeth 7-2 respectively. The stationary teeth of the external feedback comb teeth 7-1 are located inside the outer frame measuring section 1-1, and the stationary teeth of the external driving comb teeth 7-2 are located inside the outer frame driving section 1-2. One end of the external torsion beam 4 is connected to the inner side of the outer frame connecting section 1-3. A first electrode 10 and a second electrode 11 are machined on the outer frame measuring section 1-1 and the outer frame driving section 1-2 respectively, for connection to external testing or driving devices.

[0038] The mirror surface 3 is machined with two symmetrical mirror isolation grooves 8, preferably two parallel mirror isolation grooves 8, which divide the mirror surface 3 into mutually isolated mirror feedback part 3-1, mirror drive part 3-2 and center part 3-3. The outer edges of the mirror feedback part 3-1 and the mirror drive part 3-2 are respectively machined with moving teeth of inner feedback comb tooth group 9-1 and inner drive comb tooth group 9-2, and the inner sides of the opposite inner frame 2 are machined with corresponding stationary teeth. The outer frame connecting part 1-3, inner frame 2, mirror 3, outer torsion beam 4, and inner torsion beam 5 are covered with an insulating layer. An inner drive wire and electrode 13 and an inner feedback wire and electrode 14 are machined on the insulating layer. All electrodes are located on the outer frame connecting part 1-3. The inner drive wire and electrode 13 passes sequentially through the outer frame connecting part 1-3, outer torsion beam 4, inner frame 2, inner torsion beam 5, and center part 3-3, with its end connected to the mirror drive part 3-2, providing a drive signal to the inner drive comb tooth assembly 9-2. The inner feedback wire and electrode 14 passes through the outer frame connecting part 1-3, outer torsion beam 4, inner frame 2, inner torsion beam 5, and center part 3-3, with its end connected to the mirror feedback part 3-1, used to measure the capacitance of the inner feedback comb tooth assembly 9-1. A third electrode 12 is also machined on the outer frame connecting part 1-3, connected to the substrate silicon material, for providing a drive signal to the comb teeth of the inner frame 2.

[0039] In this embodiment, the two-dimensional electrostatic scanning micromirror provides drive signals to the outer frame 1, inner frame 2, and the comb teeth assembly on the mirror surface 3 via the second electrode 11, the third electrode 12, and the inner drive wire and electrode 13, respectively. Under the action of electrostatic force, the inner frame 2 drives the mirror surface 3 to deflect around the outer torsion beam 4, while the mirror surface 3 deflects around the inner torsion beam 5 in another direction. As the moving and stationary teeth of the driving comb teeth assembly separate under the electrostatic force, the moving and stationary teeth of the corresponding feedback comb teeth assembly also form a certain angle and have a certain capacitance value. At this time, by testing the capacitance of the outer feedback comb teeth assembly 7-1, the angle of rotation of the inner frame 2 and the mirror surface 3 in one direction can be obtained; simultaneously, by testing the capacitance of the inner feedback comb teeth assembly 9-1, the angle of rotation of the mirror surface 3 in the other direction can be obtained. Through the structure of this invention, the angle of deflection of the mirror surface 3 in two mutually perpendicular directions can be effectively measured in real time.

[0040] To achieve the above technical effects, this invention divides the outer frame 1 into four parts with different functions by setting multiple outer frame isolation slots 6 on the outer frame 1, simultaneously realizing internal and external driving and internal and external capacitive feedback functions. Furthermore, the mirror surface 3 is effectively divided into three regions by the mirror isolation slots 8, and with the special arrangement of the wires, driving and capacitive feedback functions are simultaneously realized on the same mirror surface. This invention sets the outer frame 1 and mirror surface 3 as multiple functional regions, realizing simultaneous internal and external driving and capacitive feedback, and real-time measurement of the deflection angle of the mirror surface 3.

[0041] Furthermore, all the isolation grooves in this invention are located on the outer frame 1 and the mirror surface 3. In particular, the isolation grooves on the mirror surface 3 are located on the edge of the mirror surface 3 near the comb teeth, away from the center of the mirror surface. The isolation grooves are insulated by insulating material, which effectively fixes the different parts together, eliminating the need to set isolation grooves on the narrow torsion beam and inner frame 2. This effectively reduces stress and stiffness problems caused by the introduction of other insulating materials, and improves the reliability of the micromirror.

[0042] Example 2:

[0043] like Figure 3 As shown, in this embodiment, the outer frame 1 is divided into an outer frame measuring section 1-1, an outer frame driving section 1-2, and an outer frame connecting section 1-3 by multiple outer frame isolation grooves 6. Unlike Embodiment 1, as... Figure 5As shown, in this embodiment, an outer frame isolation groove 6 is located at the position of the stationary teeth on one side of the outer frame 1. The outer frame isolation groove 6 divides one side of the outer frame 1 into an outer frame measuring part 1-1 and an outer frame driving part 1-2. The inner side of the outer frame measuring part 1-1 is connected to a portion of the stationary teeth, which together with the moving teeth corresponding to the inner frame 2 form an external feedback comb tooth group 7-1. The inner side of the outer frame driving part 1-2 is connected to another portion of the stationary teeth, which together with the moving teeth corresponding to the inner frame 2 form an external driving comb tooth group 7-2. At the same time, the comb tooth group under the entire micromirror is also an external driving comb tooth group 7-2.

[0044] The outer frame isolation groove 6, with its special structure, allows for the rational allocation of the number of drive teeth and feedback teeth. In actual design and manufacturing, the outer frame isolation groove 6 can be positioned appropriately based on the required driving force and feedback capacitance of the micromirror, thereby obtaining a reasonable number of drive teeth and feedback teeth to meet both driving and feedback requirements.

[0045] like Figure 4 As shown, the isolation groove on the mirror 3 in this embodiment is different from that in Embodiment 1. The mirror isolation groove 8 on the left divides the mirror 3 into a mirror driving part 3-2 and a central part 3-3. The outer side of the mirror driving part 3-2 is the inner driving comb tooth group 9-2. The mirror isolation groove 8 on the right is T-shaped, dividing the right side of the mirror 3 into the upper mirror driving part 3-2 and the lower mirror feedback part 3-1. The mirror driving part 3-2 is connected to a portion of the comb teeth on the right side of the mirror 3. This portion of the comb teeth, as moving teeth, forms the inner driving comb tooth group 9-2 with the stationary teeth corresponding to the inner frame 2. The mirror feedback part 3-1 is connected to other comb teeth, and forms the inner feedback comb tooth group 9-1 with the stationary teeth corresponding to the inner frame 2. The inner feedback wire and electrode 14 are the same as in Embodiment 1, connecting to the mirror feedback part 3-1 for detecting capacitance signals. The portion of the inner driving wire and electrode 13 on the mirror 3 is T-shaped, connecting to the mirror driving parts 3-2 on both the left and right sides of the mirror, for providing driving signals. Of course, the mirror isolation grooves 8 on both sides can also be set as T-shaped structures, dividing the mirrors on both sides into the upper mirror driving part 3-2 and the lower mirror feedback part 3-1, and then using corresponding feedback wires.

[0046] The mirror isolation groove 8 with this special structure can effectively distribute the number of drive teeth and feedback teeth. In the actual design and manufacturing process, the mirror isolation groove 8 of a suitable shape can be set according to the required driving force and the required feedback capacitance value to meet the needs of both driving and feedback.

[0047] Example 3:

[0048] like Figure 6As shown, in this embodiment, the mirror isolation groove 8 on the left side of the mirror 3 is the same as in Embodiment 1, dividing the mirror 3 into a mirror driving section 3-2 and a central section 3-3. The mirror isolation groove 8 on the right side extends through the entire mirror surface and includes two branch isolation grooves in a double-T shape, dividing the right side of the mirror 3 into three parts: the upper mirror driving section 3-2, the middle mirror feedback section 3-1, and the lower mirror driving section 3-2. The two mirror driving sections 3-2 are connected to a portion of the comb teeth on the right side of the mirror 3. This portion of the comb teeth, as moving teeth, forms an inner driving comb tooth group 9-2 with the stationary teeth corresponding to the inner frame 2. The mirror feedback section 3-1 is connected to the middle comb teeth and forms an inner feedback comb tooth group 9-1 with the stationary teeth corresponding to the inner frame 2. The inner feedback wire and electrode 14 are the same as in Embodiment 1, connecting to the mirror feedback section 3-1 for detecting capacitance signals. The inner drive wire and electrode 13 are divided into two branches on the inner frame, which enter the mirror 3 from the upper and lower inner torsion beams 5 respectively, forming multiple contact ends, which are all connected to the multiple mirror drive parts 3-2 on the mirror 3 to provide drive signals.

[0049] Of course, the double-T-shaped mirror isolation groove 8 can divide the right mirror 3 into the central mirror driving section 3-2 and the two end mirror feedback sections 3-1. Similar to Embodiment 2, the mirror isolation groove 8 with this special structure can effectively distribute the number of driving teeth and feedback teeth. In actual design and manufacturing, a mirror isolation groove 8 of appropriate shape can be set according to the required driving force and the required feedback capacitance value to meet the needs of both driving and feedback.

[0050] Example 4:

[0051] In embodiments one through three, the mirror isolation groove 8 is a straight line structure. In this embodiment, as... Figure 7 As shown, the mirror isolation groove 8 has a zigzag structure. (As...) Figure 8 As shown, the mirror isolation groove 8 has a curved structure. The complex structure of the mirror isolation groove 8 increases the contact area between the filling material and the substrate material, thereby improving the overall reliability of the mirror structure.

[0052] Example 5:

[0053] In this embodiment, the mirror 3 can be made into a circular or elliptical geometric shape according to actual needs.

[0054] Internal and external torsion beams can be processed into straight beams, folded beams, or other structures.

[0055] Example 6:

[0056] Figure 9 shows a simplified flowchart of the fabrication of the micromirror of the present invention. This diagram is only used to briefly explain the manufacturing process of some of the isolation grooves, metal wires and electrodes of the present invention, and is not intended to limit the structure of the micromirror of the present invention.

[0057] Step 1: As Figure 9A As shown, photoresist 21 is coated on SOI silicon wafer 22, and the required isolation trenches are etched through photolithography, etching and other processes.

[0058] Step 2: As Figure 9B As shown, insulating material 23 is deposited on the front side of SOI silicon wafer 22 to fill the isolation trench, and then the micromirror surface is flattened by chemical mechanical polishing process, while the silicon wafer surface still retains a layer of insulating material 23.

[0059] The insulating material 23 filling the isolation groove is SiN, SiO2 or other semiconductor insulating materials.

[0060] Step 3: As Figure 9C As shown, contact holes are etched on the insulating material 23 on the front side of the SOI silicon wafer 22 through photolithography and etching processes; then metal 24 is deposited and metal electrodes and wires with specified patterns are etched to form a mirror, metal electrodes and wires.

[0061] Metal 24 is made of conductive materials such as gold, copper, aluminum, and silver.

[0062] Step 4: As Figure 9D As shown, the comb teeth, inner and outer frames, and mirror surface are fabricated through photolithography and etching processes on the front and back sides. As shown in the cross-sectional view of the mirror surface, it can be seen that the mirror isolation groove 8, composed of insulating material 23, divides the mirror surface 3 into a mirror feedback part 3-1, a mirror driving part 3-2, and a central part 3-3 that are isolated from each other.

[0063] The above description is an explanation of the present invention and not a limitation thereof. The present invention can be modified in any form without departing from its spirit.

Claims

1. A two-dimensional electrostatic scanning micromirror, comprising an outer frame (1), an inner frame (2), and a mirror (3), wherein the outer frame (1) and the inner frame (2) are connected by an outer torsion beam (4), and the inner frame (2) and the mirror (3) are connected by an inner torsion beam (5), wherein the directions of the inner torsion beam (5) and the outer torsion beam (4) are perpendicular to each other, characterized in that: The outer frame (1) is provided with an outer frame isolation groove (6), which divides the outer frame (1) into an outer frame measuring part (1-1), an outer frame driving part (1-2), and two outer frame connecting parts (1-3); an outer feedback comb tooth group (7-1) is provided between the outer frame measuring part (1-1) and the inner frame (2), and an outer drive comb tooth group (7-2) is provided between the outer frame driving part (1-2) and the inner frame (2); the mirror (3) is provided with a mirror isolation groove (8), which divides the mirror (3) into a mirror feedback part (3-1), a mirror driving part (3-2), and a center part (3-3); an inner feedback comb tooth group (9-1) and an inner drive comb tooth group (9-2) are provided between the mirror feedback part (3-1) and the mirror driving part (3-2) and the inner frame (2), respectively. The micromirror has an insulating layer on its surface, on which an internal driving wire and electrode (13) and an internal feedback wire and electrode (14) are processed. The electrodes are located on the outer frame connecting part (1-3). The ends of the wires of the internal driving wire and electrode (13) are connected to the mirror driving part (3-2). The ends of the wires of the internal feedback wire and electrode (14) are connected to the mirror feedback part (3-1). The outer frame measuring part (1-1) and the outer frame driving part (1-2) are respectively processed with a first electrode (10) and a second electrode (11). The outer frame connecting part (1-3) is processed with a third electrode (12) that is connected to the silicon substrate of the micromirror. The outer frame (1) is processed with four outer frame isolation grooves (6). The mirror (3) is processed with two symmetrical mirror isolation grooves (8). It also includes at least one of the following: a) and b) a) The outer frame isolation groove (6) is located at the position of the stationary tooth on one side of the outer frame (1), dividing one side of the outer frame (1) into an outer frame measuring part (1-1) and an outer frame driving part (1-2); the stationary tooth on the inner side of the outer frame measuring part (1-1) and the moving tooth corresponding to the inner frame (2) form an external feedback comb tooth group (7-1), and the stationary tooth on the inner side of the outer frame driving part (1-2) and the moving tooth corresponding to the inner frame (2) form an external driving comb tooth group (7-2). b) The mirror isolation groove (8) on at least one side of the mirror (3) divides the mirror (3) into a mirror driving part (3-2) and a central part (3-3); the mirror isolation groove (8) on the other side divides one side of the mirror (3) into a mirror driving part (3-2) and a mirror feedback part (3-1). The moving teeth connected to the mirror driving part (3-2) and the stationary teeth corresponding to the inner frame (2) form an inner driving comb group (9-2). The moving teeth connected to the mirror feedback part (3-1) and the stationary teeth corresponding to the inner frame (2) form an inner feedback comb group (9-1).

2. The two-dimensional electrostatic scanning micromirror according to claim 1, characterized in that: The inner drive wire and electrode (13) passes through the outer frame connecting part (1-3), outer torsion beam (4), inner frame (2), inner torsion beam (5), and center part (3-3) in sequence, and the end is connected to the mirror drive part (3-2); the inner feedback wire and electrode (14) passes through the outer frame connecting part (1-3), outer torsion beam (4), inner frame (2), inner torsion beam (5), and center part (3-3) in sequence, and the end is connected to the mirror feedback part (3-1).

3. The two-dimensional electrostatic scanning micromirror according to claim 1, characterized in that: The isolation groove on the mirror (3) is located at the edge of the mirror (3) near the comb teeth.

4. The two-dimensional electrostatic scanning micromirror according to claim 1, characterized in that: The mirror isolation groove (8) consists of two parallel straight lines.

5. The two-dimensional electrostatic scanning micromirror according to claim 1, characterized in that: The portion of the internal driving wire and electrode (13) on the mirror (3) is T-shaped and simultaneously connected to the mirror driving part (3-2) on both sides of the mirror (3) to provide driving signals.

6. The two-dimensional electrostatic scanning micromirror according to claim 5, characterized in that: The mirror isolation groove (8) on at least one side is T-shaped.

7. The two-dimensional electrostatic scanning micromirror according to claim 5, characterized in that: The mirror isolation groove (8) on at least one side is double-T shaped.

8. The two-dimensional electrostatic scanning micromirror according to claim 1, characterized in that: The mirror isolation groove (8) has a broken line structure or a curved structure.

9. The two-dimensional electrostatic scanning micromirror according to claim 1, characterized in that: The mirror (3) is square, circular or elliptical in shape; the outer torsion beam (4) and the inner torsion beam (5) are straight beams or folded beams.

10. The two-dimensional electrostatic scanning micromirror according to claim 1, characterized in that: The outer frame isolation groove (6) and the mirror isolation groove (8) are filled with insulating material.

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