MEMS micromirror and electromagnetic MEMS micromirror

Abstract

The embodiment of the invention discloses an MEMS micromirror and an electromagnetic MEMS micromirror. The electromagnetic MEMS micromirror comprises a substrate, an annular bearing part, a reflecting mirror, a coil, an x-axis torsion beam, a y-axis torsion beam, a piezoresistive feedback structure, an input terminal and an output terminal. Specifically, the substrate is provided with a hollow structure, the annular bearing part is rotatably arranged in the hollow structure, the reflector is connected with the annular bearing part, the coil is arranged on the annular bearing part, the x-axis torsion beam is connected with the substrate and the annular bearing part, the y-axis torsion beam is connected with the reflector and the annular bearing part, and the input terminal inputs an excitation signal to drive the coil. The output terminal outputs a piezoresistive feedback signal transmitted by the piezoresistive feedback structure, and the piezoresistive feedback structure comprises a first piezoresistive feedback structure located on the x-axis torsion beam and a second piezoresistive feedback structure located on the y-axis torsion beam. Wherein the input terminal and the output terminal are located on the same side of the MEMS micromirror.

Description

Technical Field

[0001] This invention relates to the field of microelectromechanical systems (MEMS) technology, and more particularly to a MEMS micromirror and an electromagnetic MEMS micromirror. Background Technology

[0002] Electromagnetic MEMS micromirrors are miniature, drivable mirror modules fabricated using Micro-Electro-Mechanical System (MEMS) technology. They are primarily used in laser scanning, optical communication, digital displays, medical imaging, augmented reality / virtual reality, drones, and autonomous driving. Existing electromagnetic MEMS micromirrors require additional wiring to signal relay components such as PCBs or FPCs, resulting in a larger overall size and limiting the mirror's surface size and rotation angle. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a MEMS micromirror and an electromagnetic MEMS micromirror, thereby reducing the overall size of the device and providing a larger mirror size and mirror rotation angle.

[0004] In a first aspect, embodiments of the present invention provide a MEMS micromirror, comprising: a substrate having a hollow structure; an annular support portion rotatably disposed within the hollow structure; a reflector connected to the annular support portion; a coil disposed on the annular support portion; an x-axis torsion beam connecting the substrate to the annular support portion; a y-axis torsion beam connecting the reflector to the annular support portion; a piezoresistive feedback structure including a first piezoresistive feedback structure and a second piezoresistive feedback structure, the piezoresistive feedback structure outputting a piezoresistive feedback signal, the first piezoresistive feedback structure being located on the x-axis torsion beam and the second piezoresistive feedback structure being located on the y-axis torsion beam; an input terminal receiving an excitation signal that drives the coil; and an output terminal outputting the piezoresistive feedback signal; wherein the input terminal and the output terminal are located on the same side of the MEMS micromirror.

[0005] In some embodiments, the first piezoresistive feedback structure includes a first resistor, a second resistor, a third resistor, and a fourth resistor, which are connected end-to-end to form a first Wheatstone bridge. The second piezoresistive feedback structure includes a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor, which are connected end-to-end to form a second Wheatstone bridge.

[0006] In some embodiments, the substrate includes a first substrate and a second substrate, and the substrate includes a stacked second wiring layer, an insulating layer and a first wiring layer.

[0007] In some embodiments, the input terminals include a first input terminal and a second input terminal, wherein the first input terminal is electrically connected to a first end of the coil through a first wiring layer, and the second input terminal is electrically connected to a second end of the coil through the first wiring layer.

[0008] In some embodiments, the first wiring layer portion connecting the first input terminal and the first end of the coil is located on the first x-axis torsion beam, and the first wiring layer portion connecting the second input terminal and the second end of the coil is located on the second x-axis torsion beam.

[0009] In some implementations, the first end of the coil and the second end of the coil are connected by a metal connection layer of the second wiring layer.

[0010] In some embodiments, the MEMS micromirror also includes a ground terminal, which is located on the same side as the input terminal and the output terminal, or on different sides.

[0011] In some embodiments, the output terminals include a first type of output terminal and a second type of output terminal. The first type of output terminal includes a first output terminal, a second output terminal, a third output terminal, and a fourth output terminal. The second type of output terminal includes a fifth output terminal, a sixth output terminal, a seventh output terminal, and an eighth output terminal. The first, second, third, and fourth output terminals are electrically connected to a first resistor, a second resistor, a third resistor, and a fourth resistor in a first Wheatstone bridge through a second wiring layer. The fifth and sixth output terminals are electrically connected to a fifth and a sixth resistor in a second Wheatstone bridge through a first wiring layer, a contact hole, and a second wiring layer. The seventh and eighth output terminals are electrically connected to a seventh and a eighth resistor in a second Wheatstone bridge through a second wiring layer.

[0012] In some embodiments, the second wiring layer portion connecting the first type of output terminal and the first Wheatstone bridge is located on the first x-axis torsion beam; the second wiring layer portion connecting the fifth output terminal, the sixth output terminal and the fifth resistor, and the sixth resistor is located on the second x-axis torsion beam; the second wiring layer portion connecting the seventh output terminal, the eighth output terminal and the seventh resistor, and the eighth resistor is located on the first x-axis torsion beam.

[0013] Secondly, embodiments of the present invention also provide an electromagnetic MEMS micromirror, comprising: a base assembly having a receiving cavity; a magnetic component disposed within the receiving cavity; as in the first aspect, the MEMS micromirror being disposed on top of the base assembly; a cover plate located above the MEMS micromirror, covering the top of the base assembly, the cover plate having a window to expose the MEMS micromirror, and a through hole; and a probe structure disposed in the through hole and exposed on the surface of the cover plate, the probe structure being electrically connected to the MEMS micromirror.

[0014] In some embodiments, the probe structure includes: a housing, which is embedded in a cover plate through a through hole; an external interface disposed in the housing; and a telescopic probe, which is electrically connected to the external interface and the MEMS micromirror, respectively.

[0015] In some embodiments, the base assembly includes: a base plate on which a magnetic component is provided; and a frame disposed on the base plate and forming a receiving cavity with the base plate.

[0016] In some embodiments, the base plate has a magnetic post; wherein, the base assembly further includes: a magnetic shielding sleeve, which is fitted onto the magnetic post, and a magnetic component is provided on the outer side of the magnetic shielding sleeve.

[0017] In some embodiments, the magnetic component includes a first magnet and a second magnet, both of which are configured as L-shaped structures, and the first magnet and the second magnet surround the outside of the magnetic shielding sleeve.

[0018] In some embodiments, the magnetic component further includes a first magnetic sheet and a second magnetic sheet, the first magnetic sheet being matched with a first magnet and disposed on top of the first magnet, and the second magnetic sheet being matched with a second magnet and disposed on top of the second magnet.

[0019] In some embodiments, the base plate and the frame are fixedly connected by a first connector; the cover plate and the frame are fixedly connected by a second connector.

[0020] This invention provides a MEMS micromirror and an electromagnetic MEMS micromirror. The electromagnetic MEMS micromirror includes a substrate, an annular support portion, a reflector, a coil, an x-axis torsion beam, a y-axis torsion beam, a piezoresistive feedback structure, an input terminal, and an output terminal. Specifically, the substrate has a hollow structure, the annular support portion is rotatably disposed within the hollow structure, the reflector is connected to the annular support portion, the coil is disposed on the annular support portion, the x-axis torsion beam connects the substrate and the annular support portion, and the y-axis torsion beam connects the reflector and the annular support portion. The input terminal inputs an excitation signal to drive the coil, and the output terminal outputs a piezoresistive feedback signal from the piezoresistive feedback structure. The piezoresistive feedback structure includes a first piezoresistive feedback structure located on the x-axis torsion beam and a second piezoresistive feedback structure located on the y-axis torsion beam. The input and output terminals are located on the same side of the MEMS micromirror for convenient wiring.

[0021] Furthermore, the electromagnetic MEMS micromirror includes a base assembly, a magnetic assembly, a MEMS micromirror, a cover plate, and a probe structure. The base assembly forms a receiving cavity, the magnetic assembly is disposed within the receiving cavity, the MEMS micromirror is disposed on top of the base assembly, and the cover plate covers the top of the base assembly, with a window on the cover plate to expose the MEMS micromirror. The cover plate also has a through hole, and the probe structure is disposed in the through hole and exposed on the surface of the cover plate. The probe structure is electrically connected to the MEMS micromirror. Thus, the electromagnetic MEMS micromirror directly connects to the MEMS micromirror via a probe structure on the cover plate, facilitating measurement, reducing the overall size of the electromagnetic MEMS micromirror, and allowing for larger mirror surface sizes and rotation angles, thereby adapting to a wider range of applications. Attached Figure Description

[0022] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings, in which: Figure 1 This is a schematic diagram of the structure of the electromagnetic MEMS micromirror provided in an embodiment of the present invention; Figure 2 This is an exploded view of the electromagnetic MEMS micromirror provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the connection of the probe structure provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the MEMS micromirror provided in the embodiment of the present invention; Figure 5 yes Figure 4 A magnified view of a portion of region A in the middle; Figure 6 yes Figure 4 A magnified view of a portion of region B in the middle; Figure 7yes Figure 4 A magnified view of a portion of region C in the middle; Figure 8 This is a schematic diagram of the MEMS micromirror adhesive removal fixture provided in an embodiment of the present invention.

[0023] Explanation of reference numerals in the attached figures: 1-Base assembly; 11-Receiving cavity; 12-Base plate; 121-Magnetic guide post; 13-Frame; 131-Notch; 14-Magnetic shielding sleeve; 141-Matching hole; 2-Magnetic assembly; 21-First magnet; 22-Second magnet; 23-First magnetic guide sheet; 24-Second magnetic guide sheet; 3-MEMS micromirror; 31-Substrate; 311-Hollow structure; 32-Annular support; 33-Reflector; 34-Coil; 3511-First input terminal; 3512-Second input terminal; 3521-First output terminal; 3522-Second output terminal; 3523-Third output terminal; 3524-Fourth... Output terminals; 3525 - Fifth output terminal; 3526 - Sixth output terminal; 3527 - Seventh output terminal; 3528 - Eighth output terminal; 353 - Grounding terminal; 3611 - First x-axis torsion beam; 3612 - Second x-axis torsion beam; 362 - Y-axis torsion beam; 37 - Metal connecting layer; 4 - Cover plate; 41 - Window; 42 - Through hole; 5 - Probe structure; 51 - Housing; 52 - External interface; 53 - Telescopic probe; 6 - First connector; 7 - Second connector; 8 - De-adhesive fixture; 81 - Top cover; 82 - Base support; 83 - Third connector; 84 - Positioning post; 85 - Receiving groove. Detailed Implementation

[0024] The present application is described below based on embodiments, but it is not limited to these embodiments. In the detailed description of the present application below, certain specific details are described in detail. Those skilled in the art can fully understand the present application without these details. To avoid obscuring the substance of the present application, well-known methods, processes, flows, elements, and circuits are not described in detail.

[0025] Furthermore, those skilled in the art should understand that the accompanying drawings provided herein are for illustrative purposes only and are not necessarily drawn to scale.

[0026] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0027] For ease of explanation, spatially related terms such as “inside,” “outside,” “below,” “below,” “lower,” “above,” “upper,” etc., are used herein to describe the relationship between one element or feature illustrated in the figure and another. It will be understood that spatially related terms may be intended to encompass different orientations of the device in use or operation besides those depicted in the figure. For example, if the device in the figure is flipped, an element described as “below” or “below” another element or feature would then be positioned “above” that other element or feature. Thus, the exemplified term “below” can encompass both above and below orientations. The device may be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially related descriptive terms used herein should be interpreted accordingly.

[0028] Unless the context explicitly requires it, words such as "including" or "contains" throughout the application should be interpreted as including rather than exclusive or exhaustive; that is, meaning "including but not limited to".

[0029] In the description of this application, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, in the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0030] Figure 1 This is a schematic diagram of the structure of the electromagnetic MEMS micromirror provided in an embodiment of the present invention. Figure 2 This is an exploded view of the electromagnetic MEMS micromirror provided in an embodiment of the present invention, combined with... Figure 1 and Figure 2As shown, the electromagnetic MEMS micromirror includes a base assembly 1, a magnetic component 2, a MEMS micromirror 3, a cover plate 4, and a probe structure 5. Specifically, the base assembly 1 forms a receiving cavity 11 for accommodating the magnetic component 2, which provides a magnetic field for the MEMS micromirror 3. Further, the MEMS micromirror 3 is disposed on top of the base assembly 1, and the cover plate 4 is located above the MEMS micromirror 3. The cover plate 4 covers the top of the base assembly 1 so that the MEMS micromirror 3 is positioned between the base assembly 1 and the cover plate 4, and the cover plate 4 has a window 41 to expose the MEMS micromirror 3. Optionally, the MEMS micromirror 3 is fixed to the top of the base assembly 1 by dispensing adhesive. Further still, the cover plate 4 also has a through hole 42, and the probe structure 5 is disposed in the through hole 42 and exposed on the surface of the cover plate 4. It is readily understood that the probe structure 5 is electrically connected to the MEMS micromirror 3. Therefore, the electromagnetic MEMS micromirror is directly electrically connected to the MEMS micromirror 3 by setting a probe structure 5 on the cover plate 4. That is, the electrical signal on the MEMS micromirror 3 is led out through the probe structure 5 nested on the cover plate 4, without the need for additional wiring to signal relay accessories such as PCB / FPC. This reduces the overall size and helps to provide a larger mirror size and mirror angle, thus adapting to a wider range of application scenarios.

[0031] Figure 3 This is a connection diagram of the probe structure provided in an embodiment of the present invention, as shown below. Figure 3 As shown, in one embodiment, the probe structure 5 includes a housing 51, an external interface 52, and a telescopic probe 53. Specifically, the housing 51 is fitted onto the cover plate 4 through a through hole 42, and the external interface 52 is disposed within the housing 51. Optionally, the housing 51 can be fitted onto the cover plate 4 via a snap-fit ​​structure. Further, the telescopic probe 53 is electrically connected to both the external interface 52 and the MEMS micromirror 3.

[0032] like Figure 2 As shown, in one embodiment, the base assembly 1 includes a base plate 12 and a frame 13. Specifically, the base plate 12 is configured as a rectangular plate structure, the frame 13 is disposed on the base plate 12 and cooperates with the base plate 12 to form a receiving cavity 11, and the magnetic component 2 is disposed on the base plate 12 to be received within the receiving cavity 11. Further, a notch 131 is formed on the top of the frame 13, and the MEMS micromirror 3 is bonded to the frame 13 along the edge of the notch 131.

[0033] like Figure 2As shown, in one embodiment, the base plate 12 has a magnetic post 121. It should be noted that the magnetic post 121 is integrally formed with the base plate 12 and is made of a magnetically conductive material. Further, the base assembly 1 also includes a magnetic shielding sleeve 14. It should be noted that the magnetic shielding sleeve 14 is fitted onto the magnetic post 121, and the magnetic component 2 is disposed on the outside of the magnetic shielding sleeve 14. Optionally, the magnetic shielding sleeve 14 has a mating hole 141 at its center, which matches the magnetic post 121, and the magnetic shielding sleeve 14 is fitted onto the magnetic post 121 through the mating hole 141. It is readily understood that the function of the base assembly 1 is to fix the magnetic component 2 and constrain the magnetic field range.

[0034] like Figure 2 As shown, in one embodiment, the magnetic component 2 includes a first magnet 21 and a second magnet 22. Specifically, both the first magnet 21 and the second magnet 22 are configured with an L-shaped structure, and their arrangement is centrally symmetrical. Further, the first magnet 21 and the second magnet 22 surround the outer side of the magnetic shielding sleeve 14. It should be noted that the magnetic shielding sleeve 14 is used to separate the first magnet 21 and the second magnet 22 to prevent them from attracting and colliding with each other. Optionally, the magnetic shielding sleeve 14 is made of aluminum.

[0035] like Figure 2 As shown, in one embodiment, the magnetic component 2 further includes a first magnetically conductive sheet 23 and a second magnetically conductive sheet 24. Specifically, the first magnetically conductive sheet 23 is matched with the first magnet 21 and disposed on the top of the first magnet 21. Correspondingly, the second magnetically conductive sheet 24 is matched with the second magnet 22 and disposed on the top of the second magnet 22. That is, the first magnetically conductive sheet 23 and the second magnetically conductive sheet 24 are respectively configured as an L-shaped structure. It should be noted that the first magnetically conductive sheet 23 and the second magnetically conductive sheet 24 are respectively attached to the surfaces of the first magnet 21 and the second magnet 22, which can further constrain the magnetic field, thereby ensuring that the MEMS micromirror 3 works efficiently within a reasonable magnetic field range. It should also be noted that the two opposite sides of the frame 13 are hollowed out, so that a portion of the first magnet 21 and the first magnetically conductive sheet 23 can be exposed from one side of the frame 13, and a portion of the second magnet 22 and the second magnetically conductive sheet 24 can be exposed from the other side of the frame 13.

[0036] like Figure 2As shown, in one embodiment, the base plate 12 and the frame 13 are fixedly connected by a first connector 6. Optionally, the first connector 6 is a screw. Further, there are four first connectors 6, which connect the base plate 12 to the bottom of the frame 13 from the four corners of the base plate 12 to ensure the connection strength between the base plate 12 and the frame 13. On the other hand, the cover plate 4 and the frame 13 are fixedly connected by a second connector 7. Optionally, the second connector 7 is a screw. Further, there are four second connectors 7, which connect the cover plate 4 to the top of the frame 13 from the four corners of the cover plate 4 to ensure the connection strength between the cover plate 4 and the frame 13.

[0037] Figure 4 This is a schematic diagram of the structure of the MEMS micromirror provided in the embodiment of the present invention, as shown below. Figure 4 As shown, in one embodiment, the MEMS micromirror 3 includes a substrate 31, an annular support portion 32, a reflector 33, and a coil 34. Specifically, the substrate 31 has a hollow structure 311, and the annular support portion 32 is rotatably disposed in the hollow structure 311. It should be noted that the substrate 31 includes a first substrate and a second substrate, and the first substrate and the second substrate are stacked. Further, the reflector 33 is connected to the annular support portion 32, and the coil 34 is disposed on the annular support portion 32. The position of the reflector 33 matches the window 41, and the shape and size of the reflector 33 match the cross-section of the magnetic post 121. For example, the cross-section of the reflector 33 and the magnetic post 121 are set to be elliptical with the same size. For example, the major axis dimension of the reflector 33 is 8 mm. It should be noted that the coil 34, located in the magnetic field generated by the magnetic component 2, applies a force to the annular support portion 32 after being energized, causing the annular support portion 32 to rotate and drive the reflector 33 to rotate. It should be further explained that setting a high-density multi-turn coil 34 on the MEMS micromirror 3 helps to increase the mirror rotation angle of the reflector 33 under the same magnetic field conditions, which will not increase the overall size of the device, and can simplify the process flow and help reduce production costs.

[0038] It should be noted that the high-density multi-turn coil 34 can be processed by nanoimprinting-electroplating-fixture removal, thereby taking advantage of the controllable morphology of photoresist in the nanoimprinting process to optimize the morphology of the coil 34, which helps to improve the performance of the MEMS micromirror 3.

[0039] like Figure 4As shown, in one embodiment, the MEMS micromirror 3 further includes an input terminal. Specifically, the input terminal is disposed on the substrate 31 and is electrically connected to the probe structure 5 and the coil 34, respectively. It should be noted that during the assembly of the MEMS micromirror 3, the telescopic probe 53 can be brought into contact with the input terminal through height control, thereby enabling the communication of electrical signals from the MEMS micromirror 3 to the external interface 52. It should be further noted that the input terminal receives an excitation signal, which is used to drive the coil 34. Because the overall packaging of the electromagnetic MEMS micromirror is secured with adhesive and screws, the contact between the telescopic probe 53 and the input terminal is less likely to loosen, preventing signal short circuits.

[0040] like Figure 4 As shown, in one embodiment, the MEMS micromirror 3 further includes an x-axis torsion beam and a y-axis torsion beam 362. Specifically, the x-axis torsion beam is connected to the substrate 31 and the annular support portion 32, and the y-axis torsion beam 362 is connected to the annular support portion 32 and the reflector 33. Further, there are two x-axis torsion beams located on opposite sides of the annular support portion 32, and two y-axis torsion beams 362 located on opposite sides of the reflector 33. Specifically, the x-axis torsion beam includes a first x-axis torsion beam 3611 and a second x-axis torsion beam 3612. When the coil 34 is energized, the reflector 33 can rotate based on the two x-axis torsion beams or the two y-axis torsion beams 362. Optionally, the cutout structure 311 of the substrate 31 extends toward the position of the x-axis torsion beam to provide sufficient torsion space for the x-axis torsion beam. It should be noted that the input terminal is located at a corner of the substrate 31, relatively far from the x-axis torsion beam. This avoids stress transmission during wire bonding or probe testing, thereby reducing the impact of abnormal stress near the input terminal on the x-axis torsion beam and improving the reliability of the MEMS micromirror 3. Furthermore, moving the input terminal helps reduce the size of the MEMS micromirror 3, thus lowering production costs.

[0041] In one embodiment, the MEMS micromirror 3 further includes a piezoresistive feedback structure and an output terminal. Specifically, the output terminal is disposed on the substrate 31 and is electrically connected to the probe structure 5. It should be noted that the input terminal and the output terminal are located on the same side of the MEMS micromirror 3, which helps to reduce the overall size of the electromagnetic MEMS micromirror and helps to provide a larger mirror surface size and mirror surface rotation angle, thereby adapting to a wider range of application scenarios. The piezoresistive feedback structure is used to characterize the rotation angle of the reflector 33. Specifically, the piezoresistive feedback structure outputs a piezoresistive feedback signal, which is then output through the output terminal. More specifically, the piezoresistive feedback structure includes a first piezoresistive feedback structure and a second piezoresistive feedback structure, the first piezoresistive feedback structure being located on the x-axis torsion beam and the second piezoresistive feedback structure being located on the y-axis torsion beam 362.

[0042] In one embodiment, the first piezoresistive feedback structure includes a first resistor, a second resistor, a third resistor, and a fourth resistor, which are connected end-to-end to form a first Wheatstone bridge. Similarly, the second piezoresistive feedback structure includes a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor, which are connected end-to-end to form a second Wheatstone bridge.

[0043] In one embodiment, the MEMS micromirror further includes a second wiring layer, an insulating layer, and a first wiring layer stacked on the substrate 31.

[0044] In one embodiment, the input terminals include a first input terminal 3511 and a second input terminal 3512. Specifically, the first input terminal 3511 is electrically connected to a first end of the coil 34 through a first wiring layer, and the second input terminal 3512 is electrically connected to a second end of the coil 34 through the first wiring layer. The portion of the first wiring layer connecting the first input terminal 3511 and the first end of the coil 34 is located on a first x-axis torsion beam 3611, and the portion of the first wiring layer connecting the second input terminal 3512 and the second end of the coil 34 is located on a second x-axis torsion beam 3612.

[0045] In one implementation, combined with Figure 4 and Figure 7 As shown, the first end and the second end of the coil 34 are connected by the metal connection layer 37 of the second wiring layer.

[0046] In one embodiment, the output terminals include a first output terminal 3521, a second output terminal 3522, a third output terminal 3523, a fourth output terminal 3524, a fifth output terminal 3525, a sixth output terminal 3526, a seventh output terminal 3527, and an eighth output terminal 3528. Specifically, in conjunction with... Figure 4 and Figure 5 As shown, the first output terminal 3521, the second output terminal 3522, the third output terminal 3523, and the fourth output terminal 3524 are electrically connected to the first resistor, the second resistor, the third resistor, and the fourth resistor in the first Wheatstone bridge via the second wiring layer. Further, in conjunction with... Figure 4 and Figure 6 As shown, the fifth output terminal 3525 and the sixth output terminal 3526 are electrically connected to the fifth and sixth resistors in the second Wheatstone bridge through the first wiring layer, contact holes, and the second wiring layer. It should be noted that the contact holes connect the first substrate and the second substrate. Furthermore, in conjunction with... Figure 4 and Figure 6As shown, the seventh output terminal 3527 and the eighth output terminal 3528 are electrically connected to the seventh and eighth resistors in the second Wheatstone bridge via the second wiring layer. The portion of the second wiring layer connecting the first type of output terminals and the first Wheatstone bridge is located on the first x-axis torsion beam 3611; the portion of the second wiring layer connecting the fifth output terminal 3525, the sixth output terminal 3526, and the fifth and sixth resistors is located on the second x-axis torsion beam 3612; and the portion of the second wiring layer connecting the seventh output terminal 3527, the eighth output terminal 3528, and the seventh and eighth resistors is located on the first x-axis torsion beam 3611. Optionally, the MEMS micromirror 3 also includes a ground terminal 353, which may be located on the same side as the input and output terminals or on different sides; that is, the ground terminal 353 can be located anywhere on the substrate.

[0047] It should be noted that, considering the difficulty in removing adhesive from the high-density coil 34 and the fragility of the mirror surface of the reflector 33, the adhesive removal method can be improved by using a matching adhesive removal fixture 8, thereby effectively removing residual adhesive from the gaps of the coil 34 and ensuring that the coil 34 can work normally in subsequent tests. Figure 8 This is a schematic diagram of the MEMS micromirror adhesive removal fixture provided in an embodiment of the present invention, as shown below. Figure 8 As shown, the adhesive removal fixture 8 includes an upper cover 81 and a base 82. Specifically, the MEMS micromirror 3 is positioned between the upper cover 81 and the base 82 during adhesive removal. Further, the upper cover 81 and the base 82 are connected by a third connector 83. Optionally, the third connector 83 can be a screw or other connecting component. It should be noted that there are two third connectors 83, distributed on opposite sides of the upper cover 81, to ensure the connection strength between the upper cover 81 and the base 82. Further still, the base 82 is provided with positioning posts 84, which are used to engage with holes on the upper cover 81 to achieve positioning between the upper cover 81 and the base 82. It should be noted that there are two positioning posts 84, distributed on opposite sides of the base 82, to ensure the positioning accuracy between the upper cover 81 and the base 82. Optionally, the positioning posts 84 and the third connector 83 are staggered. In one embodiment, the base is provided with multiple receiving slots 85. Furthermore, during the adhesive removal process, either static immersion or ultrasonic immersion can be used. Even further, after the MEMS micromirror 3 is thoroughly cleaned, it will fall into the pre-reserved receiving groove 85 on the base 82, thus preventing the MEMS micromirror 3 from moving and causing damage.

[0048] This invention provides a MEMS micromirror and an electromagnetic MEMS micromirror. The electromagnetic MEMS micromirror includes a substrate, an annular support portion, a reflector, a coil, an x-axis torsion beam, a y-axis torsion beam, a piezoresistive feedback structure, an input terminal, and an output terminal. Specifically, the substrate has a hollow structure, the annular support portion is rotatably disposed within the hollow structure, the reflector is connected to the annular support portion, the coil is disposed on the annular support portion, the x-axis torsion beam connects the substrate and the annular support portion, and the y-axis torsion beam connects the reflector and the annular support portion. The input terminal inputs an excitation signal to drive the coil, and the output terminal outputs a piezoresistive feedback signal from the piezoresistive feedback structure. The piezoresistive feedback structure includes a first piezoresistive feedback structure located on the x-axis torsion beam and a second piezoresistive feedback structure located on the y-axis torsion beam. The input and output terminals are located on the same side of the MEMS micromirror, which helps to reduce the overall size of the electromagnetic MEMS micromirror and allows for a larger mirror surface size and mirror rotation angle, thus adapting to a wider range of applications.

[0049] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A MEMS micromirror, characterized in that, include: A substrate having a hollow structure; An annular support portion, which is rotatably disposed within the hollow structure; A reflector, wherein the reflector is connected to the annular support portion; A coil, the coil being disposed on the annular support portion; The base plate is connected to the annular support portion via the x-axis torsion beam. A torsion beam along the y-axis, through which the reflector is connected to the annular support portion; A piezoresistive feedback structure, comprising a first piezoresistive feedback structure and a second piezoresistive feedback structure, wherein the piezoresistive feedback structure outputs a piezoresistive feedback signal, the first piezoresistive feedback structure is located on the x-axis torsion beam, and the second piezoresistive feedback structure is located on the y-axis torsion beam; An input terminal is provided, wherein an excitation signal is input to the input terminal, and the excitation signal drives the coil. as well as The piezoresistive feedback signal is output through the output terminal. The input terminal and the output terminal are located on the same side of the MEMS micromirror.

2. The MEMS micromirror according to claim 1, characterized in that, The first piezoresistive feedback structure includes a first resistor, a second resistor, a third resistor, and a fourth resistor. The first resistor, the second resistor, the third resistor, and the fourth resistor are connected end to end to form a first Wheatstone bridge. The second piezoresistive feedback structure includes a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor. The fifth resistor, the sixth resistor, the seventh resistor, and the eighth resistor are connected end to end to form a second Wheatstone bridge.

3. The MEMS micromirror according to claim 2, characterized in that, The substrate includes a first substrate and a second substrate, and the substrate includes a stacked second wiring layer, an insulating layer and a first wiring layer.

4. The MEMS micromirror according to claim 3, characterized in that, The input terminals include a first input terminal and a second input terminal. The first input terminal is electrically connected to a first end of the coil through the first wiring layer, and the second input terminal is electrically connected to a second end of the coil through the first wiring layer.

5. The MEMS micromirror according to claim 4, characterized in that, The first wiring layer portion connecting the first input terminal and the first end of the coil is located on the first x-axis torsion beam, and the first wiring layer portion connecting the second input terminal and the second end of the coil is located on the second x-axis torsion beam.

6. The MEMS micromirror according to claim 5, characterized in that, The first end and the second end of the coil are connected through the metal connection layer of the second wiring layer.

7. The MEMS micromirror according to claim 1, characterized in that, The MEMS micromirror also includes a grounding terminal, which is located on the same side as the input terminal and the output terminal, or on different sides.

8. The MEMS micromirror according to claim 3, characterized in that, The output terminals include a first type of output terminals and a second type of output terminals. The first type of output terminals includes: a first output terminal, a second output terminal, a third output terminal, and a fourth output terminal; the second type of output terminals includes: a fifth output terminal, a sixth output terminal, a seventh output terminal, and an eighth output terminal. The first output terminal, the second output terminal, the third output terminal, and the fourth output terminal are electrically connected to the first resistor, the second resistor, the third resistor, and the fourth resistor in the first Wheatstone bridge through the second wiring layer; The fifth output terminal and the sixth output terminal are electrically connected to the fifth resistor and the sixth resistor in the second Wheatstone bridge through the first wiring layer, the contact hole, and the second wiring layer. The seventh output terminal and the eighth output terminal are electrically connected to the seventh resistor and the eighth resistor in the second Wheatstone bridge through the second wiring layer.

9. The MEMS micromirror according to claim 8, characterized in that, The second wiring layer portion connecting the first type of output terminal and the first Wheatstone bridge is located on the first x-axis torsion beam; the second wiring layer portion connecting the fifth output terminal, the sixth output terminal and the fifth resistor, and the sixth resistor is located on the second x-axis torsion beam; the second wiring layer portion connecting the seventh output terminal, the eighth output terminal and the seventh resistor, and the eighth resistor is located on the first x-axis torsion beam.

10. An electromagnetic MEMS micromirror, characterized in that, The electromagnetic MEMS micromirror includes: A base assembly having a receiving cavity; A magnetic component, wherein the magnetic component is disposed within the receiving cavity; The MEMS micromirror as described in any one of claims 1-9, wherein the MEMS micromirror is disposed on the top of the base assembly; A cover plate, located above the MEMS micromirror, covering the top of the base assembly, having a window to expose the MEMS micromirror, and also having a through hole; and A probe structure is disposed in the through hole and exposed on the surface of the cover plate, and the probe structure is electrically connected to the MEMS micromirror.

11. The electromagnetic MEMS micromirror according to claim 10, characterized in that, The probe structure includes: The outer casing is fitted into the cover plate through the through-hole; External interface, the external interface being disposed within the housing; and A telescopic probe, which is electrically connected to both the external interface and the MEMS micromirror.

12. The electromagnetic MEMS micromirror according to claim 10, characterized in that, The base assembly includes: A base plate, wherein the magnetic component is disposed on the base plate; and A frame is disposed on the base plate and forms the receiving cavity with the base plate.

13. The electromagnetic MEMS micromirror according to claim 12, characterized in that, The base plate has magnetic posts; The base assembly further includes: A magnetic shielding sleeve is fitted onto the magnetic post, and the magnetic component is provided on the outer side of the magnetic shielding sleeve.

14. The electromagnetic MEMS micromirror according to claim 13, characterized in that, The magnetic component includes a first magnet and a second magnet, both of which are configured as L-shaped structures and surround the outer side of the magnetic shielding sleeve.

15. The electromagnetic MEMS micromirror according to claim 14, characterized in that, The magnetic component further includes a first magnetic conductive sheet and a second magnetic conductive sheet. The first magnetic conductive sheet is matched with the first magnet and disposed on the top of the first magnet, and the second magnetic conductive sheet is matched with the second magnet and disposed on the top of the second magnet.

16. The electromagnetic MEMS micromirror according to claim 12, characterized in that, The base plate and the frame are fixedly connected by a first connector; The cover plate and the frame are fixedly connected by a second connector.

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