MEMS micromirror structure with vertical comb teeth and manufacturing method of MEMS micromirror structure

Abstract

The invention relates to the technical field of MEMS micromirrors. The invention particularly relates to an MEMS micromirror structure with vertical comb teeth and a manufacturing method thereof. The micro-mirror structure comprises a supporting layer and a micro-mirror layer, the supporting layer comprises a fixed comb electrode, and the micro-mirror layer comprises a micro-mirror platform and a movable comb electrode; the fixed comb electrodes and the movable comb electrodes are arranged in a staggered manner; the bonding layer is positioned between the supporting layer and the micro-mirror layer and is used for connecting the supporting layer and the micro-mirror layer; the connecting metal layer penetrates through the bonding layer in the thickness direction, is connected with the supporting layer and the micro-mirror layer and is electrically conducted with the movable comb tooth electrode; the fixed comb tooth electrode is suitable for leading out a signal to the lower part of the supporting layer through the fixed block connected with the fixed comb tooth electrode; the movable comb electrode is suitable for leading out signals to the lower portion of the supporting layer through the connecting metal layer and the connecting blocks. The MEMS micromirror structure provided by the invention is beneficial to miniaturized integrated packaging with other device structures, is simple in process and good in product consistency, and is suitable for batch production.

Description

Technical Field

[0001] The present application relates to the field of MEMS micromirror technology, and more particularly to a vertical comb-teeth MEMS micromirror structure and a manufacturing method thereof. Background Art

[0002] Electrostatically driven MEMS micromirrors can be categorized into two types: planar comb drive and vertical comb drive. Vertical comb drive involves dividing the driving comb electrodes into two groups, fixed and movable, alternating between upper and lower layers. Compared to planar comb drive, this drive structure eliminates the pull-to-pull effect between the comb electrodes and enables torsional plasmon motion, providing greater driving force.

[0003] Existing vertical comb-drive MEMS micromirror structures, with comb-tooth electrodes distributed across two layers, require two separate layers for signal connection to external control circuits, hindering compact integration with other device structures. Furthermore, the manufacturing process often requires precise alignment and bonding, introduces additional stress treatment, or requires high-temperature processing, resulting in poor device quality consistency, making mass production difficult and complex.

[0004] Therefore, a solution is needed to solve the problems that the electrostatically driven MEMS micromirror structure with vertical comb teeth is not conducive to miniaturized integrated packaging with other device structures, and the process is complex and the product consistency is poor and not suitable for mass production. Summary of the Invention

[0005] Therefore, the present application provides a vertical comb-tooth MEMS micromirror structure and a manufacturing method thereof to solve the problem that the vertical comb-tooth electrostatically driven MEMS micromirror structure is not conducive to miniaturized integrated packaging with other device structures, and the process is complex and the product consistency is poor and not suitable for mass production.

[0006] In one aspect of the present application, the present application provides a vertical comb-tooth MEMS micromirror structure, comprising: a supporting layer and a micromirror layer, the supporting layer comprising a fixed comb-tooth electrode, the micromirror layer comprising a micromirror platform and a movable comb-tooth electrode; the fixed comb-tooth electrode and the movable comb-tooth electrode are staggered; a bonding layer, located between the supporting layer and the micromirror layer, connecting the supporting layer and the micromirror layer; a connecting metal layer, penetrating the bonding layer in the thickness direction, the connecting metal layer connecting the supporting layer and the micromirror layer, and electrically conducting with the movable comb-tooth electrode; the MEMS micromirror structure further comprises a fixed block located on the supporting layer and a connecting block located on the supporting layer and the micromirror layer, the fixed comb-tooth electrode being suitable for leading out a signal to the bottom of the supporting layer through the fixed block connected to itself; the movable comb-tooth electrode being suitable for leading out a signal to the bottom of the supporting layer through the connecting block via the connecting metal layer.

[0007] The vertical comb-tooth MEMS micromirror structure provided by the present application has a connecting metal layer connecting the upper micromirror layer and the lower supporting layer embedded in the bonding layer between the supporting layer and the micromirror layer, so that the micromirror platform and the movable comb-tooth electrode are electrically connected to the supporting layer below, so that the signal can be extracted from below the supporting layer. Since the fixed comb-tooth electrode is originally located in the supporting layer below, the signal is usually extracted from below the supporting layer. As a result, the movable comb-tooth electrode, the micromirror platform and the fixed comb-tooth electrode can all be extracted from below the supporting layer, and then the signal circuit can be connected only below the supporting layer, without having to be extracted from two directions below the supporting layer and above the micromirror layer as in the traditional structure. This simplifies the circuit extraction path, and the single-sided extraction makes it easier to arrange the circuit, which is beneficial to the miniaturization and integrated packaging of the MEMS micromirror structure and other device structures. In addition, this structure needs to adopt a method of bonding first and then etching. Compared with the traditional method of etching separately first and then bonding, the process difficulty is lower, and no high-temperature treatment or introduction of additional stress is required. Therefore, the device quality consistency is good, suitable for mass production, and the process is simple.

[0008] In some embodiments of the present application, the supporting layer includes a lower frame, the micromirror layer includes an upper frame, and the lower frame and the upper frame are bonded to each other through a bonding layer; the fixed block is connected to the upper frame through a bonding layer and is spaced apart from the lower frame; the fixed comb electrode is fixedly connected to the fixed block; the connecting block includes an upper connecting block located on the micromirror layer and a lower connecting block located on the supporting layer; the lower connecting block and the fixed block are respectively connected to the upper frame and are not conductive to each other; the upper connecting block is spaced apart from the upper frame and is connected to the torsion beam; the torsion beam connects the micromirror platform and the movable comb electrode; the lower connecting block is respectively bonded to the upper connecting block and the upper frame through a bonding layer; the connecting metal layer is located in the bonding layer between the upper connecting block and the lower connecting block, and is respectively connected to the upper connecting block and the lower connecting block.

[0009] The vertical comb-tooth MEMS micromirror structure provided in the present application is connected by bonding the upper frame and the lower frame through a bonding layer, and the upper and lower connecting blocks are connected to the torsion beam to connect the micromirror platform and the movable comb-tooth electrode, and the fixed block is connected to the fixed comb-tooth electrode. The connecting block and the fixed block are not conductive to each other, so that the circuits of the micromirror platform and the movable comb-tooth electrode and the fixed comb-tooth electrode are completely separated, and the leads on the same side will not interfere with each other.

[0010] In some embodiments of the present application, the torsion beam extends along a first direction and is located at both ends of the micromirror platform in the first direction; the movable comb electrode is located on the side of the torsion beam on both sides of the micromirror platform along the first direction and extends in a second direction; the second direction is perpendicular to the first direction; the fixed comb electrode is located below the movable comb electrode and is staggered with the movable comb electrode along the first direction, and the fixed comb electrode is aligned with the gaps between adjacent teeth in the movable comb electrode; the fixed blocks are located on both sides below the torsion beam and are arranged at intervals along the second direction.

[0011] In some embodiments of the present application, the vertical comb-tooth MEMS micromirror structure also includes: a mirror reflection layer, located on the upper surface of the micromirror platform; a transfer layer, the transfer layer includes a transfer substrate and a connecting through-hole penetrating the transfer substrate in the thickness direction; the transfer layer also includes an insulating isolation layer covering the upper surface, the lower surface of the transfer layer and the inner wall of the connecting through-hole; the transfer layer also includes an upper connection layer on the upper surface of the insulating isolation layer and a lower connection layer of the insulating isolation layer; the connecting through-hole fills the remaining space with conductive metal, connecting the upper connection layer and the lower connection layer; a lead-out layer, the lead-out layer is located on the lower surface of the fixed block and the lower surface of the lower connecting block; the upper connection layer is electrically connected to the lead-out layer through a conductive connection structure, and the lower connection layer is connected to the ASIC chip through a conductive connection structure; the lower connection layer is also connected to the substrate through a conductive connection structure, and the ASIC chip is located between the conductive connection structures connecting the substrate.

[0012] The vertical comb-tooth MEMS micromirror structure provided in this application can be connected to an ASIC chip through a transfer layer, and the ASIC chip is placed under the overall structure and then connected to a substrate to achieve an integrated miniaturized packaging of the overall micromirror structure.

[0013] In some embodiments of the present application, the bonding layer includes a first insulating layer on the upper surface of the supporting layer and a second insulating layer on the lower surface of the micromirror layer, and a bonding metal layer between the first insulating layer and the second insulating layer; the bonding metal layer is a patterned metal layer; and the connecting metal layer is connected to the bonding metal layer.

[0014] In the vertical comb-tooth MEMS micromirror structure provided in the present application, a bonding connection between the support layer and the micromirror layer is achieved through a bonding metal layer in the bonding layer, while the first insulating layer and the second insulating layer ensure that there is no full direct electrical conduction between the bonding layer and the micromirror layer, and only the position of the bonding metal layer is electrically connected through the bonding metal layer.

[0015] In some embodiments of the present application, the material of the support layer and the micromirror layer includes silicon; the material of the bonding metal layer is gold; the material of the connecting metal layer includes gold or copper; the material of the first insulating layer includes silicon dioxide; the material of the second insulating layer includes silicon dioxide; the material of the mirror reflection layer includes gold; the material of the lead-out layer includes gold or copper; the material of the transfer substrate includes silicon; the material of the insulating isolation layer includes silicon dioxide; the material of the upper connection layer includes gold or copper; the material of the lower connection layer includes gold or copper; the material of the conductive metal includes gold or copper; and the conductive connection structure includes solder balls or conductive bumps.

[0016] In another aspect of the present application, the present application provides a method for manufacturing a vertical comb-tooth MEMS micromirror structure, comprising the following steps: providing an initial support layer and an initial micromirror layer; bonding the initial support layer and the initial micromirror layer through a bonding layer and a connecting metal layer, wherein the connecting metal layer penetrates the bonding layer in the thickness direction, and the connecting metal layer connects the support layer and the micromirror layer; etching the initial micromirror layer to complete the patterning of the initial micromirror layer to form a micromirror layer, which at least includes a micromirror platform and a movable comb-tooth electrode; electrically conducting the connecting metal layer with the movable comb-tooth electrode; etching the initial support layer to complete the patterning of the initial support layer to form a support layer, which at least includes a fixed comb-tooth electrode; removing part of the bonding layer to complete the release of the micromirror platform and the movable comb-tooth electrode, and making the structures connected to the fixed comb-tooth electrode and the movable comb-tooth electrode non-conductive with each other.

[0017] The manufacturing method of the vertical comb-tooth MEMS micromirror structure provided in the present application is suitable for manufacturing the vertical comb-tooth MEMS micromirror structure provided in the present application. In the bonding layer between the support layer and the micromirror layer, a connecting metal layer connecting the upper micromirror layer and the lower support layer is buried, so that the micromirror platform and the movable comb-tooth electrode are electrically connected to the support layer below, so that the signal can be extracted from below the support layer. Since the fixed comb-tooth electrode is originally located in the support layer below, the signal is usually extracted from below the support layer. As a result, the movable comb-tooth electrode, the micromirror platform and the fixed comb-tooth electrode can all be extracted from below the support layer, and then the signal circuit can be connected only below the support layer, without having to extract from two directions, namely from below the support layer and above the micromirror layer, as in the traditional structure. This simplifies the circuit extraction path, and the single-sided extraction makes it easier to arrange the circuit, which is beneficial to the miniaturized integrated packaging of the MEMS micromirror structure and other device structures. In addition, the present structure needs to adopt a method of bonding first and then etching. Compared with the traditional method of etching separately and then bonding, the process is less difficult and does not require high-temperature treatment or the introduction of additional stress. Therefore, the device quality is consistent, suitable for mass production, and the process is simple.

[0018] In some embodiments of the present application, the step of bonding the initial support layer and the initial micromirror layer through the bonding layer and the connecting metal layer includes: forming a first insulating layer on one side of the initial support layer; patterning the first insulating layer to form a first connecting opening, exposing a portion of the initial support layer; forming a first bonding metal layer, covering the first insulating layer, and filling the first connecting opening; forming a second insulating layer on one side of the initial micromirror layer; patterning the second insulating layer to form a second connecting opening, exposing a portion of the initial micromirror layer; the second connecting opening corresponds to the position of the first connecting opening; forming a second bonding metal layer, covering the second insulating layer, and filling the second connecting opening; bonding the initial support layer and the initial micromirror layer through the first bonding metal layer. The bonding metal layer and the second bonding metal layer are bonded to each other; the first bonding metal layer and the second bonding metal layer between the first insulating layer and the second insulating layer form a bonding metal layer; at the same time, the first bonding metal layer filling the first connection opening and the second bonding metal layer filling the second connection opening are correspondingly connected to form a connection metal layer; in the step of etching the initial micromirror layer, the first insulating layer and the bonding metal layer at the corresponding etching position are synchronously etched and removed; in the step of etching the initial support layer, the second insulating layer and the bonding metal layer at the corresponding etching position are synchronously etched and removed; in the step of releasing the micromirror platform and the movable comb tooth electrode, the portion of the remaining bonding layer located between the micromirror platform and the movable comb tooth and the support layer is removed.

[0019] The manufacturing method of the vertical comb-tooth MEMS micromirror structure provided in the present application adopts a bonding-first-then-etching method, using a bonding layer of a composite structure composed of a first insulating layer, a bonding metal layer, and a second insulating layer to provide support for the micromirror layer during etching and isolate the micromirror layer from the support layer. In this way, the two sides will not interfere with each other during etching, and the unnecessary connecting parts are finally removed to realize the release of the upper and lower layer structures. There is no need to introduce high temperature or other stress processes, and the process difficulty is greatly reduced.

[0020] In some embodiments of the present application, the step of bonding the initial support layer and the initial micromirror layer via the bonding layer and the connecting metal layer includes: forming a first insulating layer on one surface of the initial support layer; patterning the first insulating layer to form a first connecting opening to expose a portion of the initial support layer; forming a first bonding metal layer to cover the first insulating layer and fill the first connecting opening; patterning the first bonding metal layer to remove the first bonding metal layer corresponding to the portion of the final structure that is not connected between the support layer and the micromirror layer; forming a second insulating layer on one surface of the initial micromirror layer; patterning the second insulating layer to form a second connecting opening to expose a portion of the initial micromirror layer; the second connecting opening corresponds to the position of the first connecting opening; and A second bonding metal layer is formed in the connection opening; the initial support layer and the initial micromirror layer are bonded and connected through the first bonding metal layer and the second bonding metal layer; the remaining first bonding metal layer between the first insulating layer and the second insulating layer forms a bonding metal layer; at the same time, the first bonding metal layer filling the first connection opening and the second bonding metal layer filling the second connection opening are correspondingly connected to form a connection metal layer; in the step of etching the initial micromirror layer, the first insulating layer is exposed; in the step of etching the initial support layer, the second insulating layer is exposed; in the step of releasing the micromirror platform and the movable comb teeth electrode, the portions of the first insulating layer and the second insulating layer located between the micromirror platform and the movable comb teeth and the support layer, as well as the suspended portions, are removed.

[0021] The present application provides a method for manufacturing a vertical comb-tooth MEMS micromirror structure. In this method, the bonding metal layer in the bonding layer is first patterned, and then etched until the insulating layer is exposed. This can further reduce the difficulty of etching. During the etching process, the insulating layer continues to provide support and isolation barriers for the upper and lower layers respectively, and finally removes the parts that need to be disconnected and blocked together. In this way, the two sides will not interfere with each other when etching. Although the process steps are slightly increased, only the step of patterning the metal layer is added first, the process difficulty is further reduced. There is no need to etch multiple layers in one step, which is beneficial for controlling the etching range, promoting the consistency of the device of the finished process, and facilitating mass production.

[0022] In some embodiments of the present application, the method for manufacturing a vertical comb-tooth MEMS micromirror structure further includes the following steps: forming a transfer layer, including: providing an initial transfer substrate, forming a connecting through hole at a portion of the surface of one side of the initial transfer substrate; forming a third insulating layer on the surface of the initial transfer substrate on the side of the connecting through hole opening, the third insulating layer also covering the inner wall of the connecting through hole; filling the remaining space in the connecting through hole with a conductive metal; forming a patterned upper connecting layer on the surface of the third insulating layer; blocking one side of the upper connecting layer, thinning the opposite side of the upper connecting layer of the initial transfer substrate until the connecting through hole is exposed and slightly lower than the first insulating layer and the conductive metal in the conductive through hole; and forming a patterned upper connecting layer on the surface of the initial transfer substrate. A fourth insulating layer is formed on the opposite surface, and the fourth insulating layer is integrally connected with the third insulating layer to form an isolation insulating layer; a patterned lower connection layer is formed on the surface of the fourth insulating layer; the manufacturing method of the vertical comb-tooth MEMS micromirror structure also includes the following steps: bonding the ASIC chip to the lower connection layer via a conductive connection structure; bonding the transfer substrate to the substrate via the conductive connection structure; forming a patterned lead-out layer on the surface of the support layer facing away from the micromirror layer, the lead-out layer being located on the surface of the portion conductive to the movable comb-tooth electrode and the surface of the portion conductive to the fixed comb-tooth electrode; bonding the bonded support layer and micromirror layer to the transfer layer via the lead-out layer and the conductive connection structure, and connecting to the upper connection layer.

[0023] The manufacturing method of the vertical comb-tooth MEMS micromirror structure provided in the present application connects the ASIC chip on one side by forming a transfer substrate and integrally packages it to the substrate, thereby realizing the integrated miniaturized integrated packaging of the vertical comb-tooth MEMS micromirror structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0025] Figure 1 A schematic perspective view of a core structural portion of a vertical comb-tooth MEMS micromirror structure according to an embodiment of the present application;

[0026] Figure 2 A schematic perspective view of the core structure of the vertical comb-tooth MEMS micromirror structure according to an embodiment of the present application from another angle;

[0027] Figure 3 for Figure 1 The cross-sectional view of the AA section line;

[0028] Figure 4 for Figure 1 The cross-sectional view of the BB section line;

[0029] Figure 5 This is a flow chart of a method for manufacturing a vertical comb-tooth MEMS micromirror structure according to an embodiment of the present application;

[0030] Figure 6-Figure 1 5 is a schematic diagram of the states in each step of a method for manufacturing a vertical comb-teeth MEMS micromirror structure according to an embodiment of the present application;

[0031] Figure 16-Figure 2 4 is a schematic diagram of the states in each step of a method for manufacturing a vertical comb-teeth MEMS micromirror structure according to another embodiment of the present application;

[0032] Figures 25-30 Schematic diagram of the states of each step in the process of integrating the core structure part with the ASIC chip and the substrate in the manufacturing method of the vertical comb-tooth MEMS micromirror structure according to one embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to solve the problems that the electrostatically driven MEMS micromirror structure with vertical comb teeth is not conducive to miniaturized integrated packaging with other device structures, and the process is complex and the product consistency is poor and not suitable for mass production, the inventors of this application have conducted careful research and proposed a MEMS micromirror structure with vertical comb teeth and its manufacturing method.

[0034] The present application provides a MEMS micromirror structure with vertical comb teeth, comprising: a supporting layer and a micromirror layer, wherein the supporting layer comprises a fixed comb tooth electrode, and the micromirror layer comprises a micromirror platform and a movable comb tooth electrode; the fixed comb tooth electrode and the movable comb tooth electrode are arranged in a staggered manner; a bonding layer, located between the supporting layer and the micromirror layer, connecting the supporting layer and the micromirror layer; a connecting metal layer, penetrating the bonding layer in a thickness direction, connecting the supporting layer and the micromirror layer, and being electrically conductive with the movable comb tooth electrode; the MEMS micromirror structure further comprises a fixed block located on the supporting layer and a connecting block located on the supporting layer and the micromirror layer, the fixed comb tooth electrode being adapted to lead out a signal to a lower portion of the supporting layer via the fixed block connected thereto; and the movable comb tooth electrode being adapted to lead out a signal to a lower portion of the supporting layer via the connecting block via the connecting metal layer.

[0035] The present application also provides a method for manufacturing a vertical comb-tooth MEMS micromirror structure, comprising the following steps: providing an initial support layer and an initial micromirror layer; bonding the initial support layer and the initial micromirror layer via a bonding layer and a connecting metal layer, wherein the connecting metal layer penetrates the bonding layer in the thickness direction, and the connecting metal layer connects the support layer and the micromirror layer; etching the initial micromirror layer to complete the patterning of the initial micromirror layer to form a micromirror layer, which at least includes a micromirror platform and a movable comb-tooth electrode; electrically conducting the connecting metal layer with the movable comb-tooth electrode; etching the initial support layer to complete the patterning of the initial support layer to form a support layer, which at least includes a fixed comb-tooth electrode; removing part of the bonding layer to complete the release of the micromirror platform and the movable comb-tooth electrode, and making the structures connected to the fixed comb-tooth electrode and the movable comb-tooth electrode non-conductive with each other.

[0036] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. In the description of the present application, it should be noted that the terms "first", "second" and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0037] Example 1

[0038] refer to Figure 1-Figure 4 This embodiment provides a vertical comb-teeth MEMS micromirror structure, comprising:

[0039] The support layer 100 and the micromirror layer 200 include a fixed comb-tooth electrode 121, and the micromirror layer 200 includes a micromirror platform 240 and a movable comb-tooth electrode 221; the fixed comb-tooth electrode 121 and the movable comb-tooth electrode 221 are arranged in a staggered manner;

[0040] The bonding layer 300 is located between the support layer 100 and the micromirror layer 200 and connects the support layer 100 and the micromirror layer 200;

[0041] The connecting metal layer 400 penetrates the bonding layer 300 in the thickness direction, connects the supporting layer 100 and the micromirror layer 200 , and is electrically connected to the movable comb-tooth electrode 221 ;

[0042] The MEMS micromirror structure also includes a fixed block 110 located on the support layer 100 and a connecting block located between the support layer 100 and the micromirror layer 200. The fixed comb-tooth electrode 121 is suitable for leading out signals to the bottom of the support layer 100 through the fixed block 120 connected to itself; the movable comb-tooth electrode 221 is suitable for leading out signals to the bottom of the support layer 100 through the connecting block via the connecting metal layer 400.

[0043] The figure does not clearly show the positions of the fixed block 120 and the connecting block for leading out the signals downward. Those skilled in the art can select the positions for opening holes and filling metal wires for leading out according to actual needs, or directly set a metal layer at the required position as a lead-out layer for leading out.

[0044] In the vertical comb-tooth MEMS micromirror structure provided in this embodiment, a connecting metal layer 400 is embedded in the bonding layer 300 between the support layer 100 and the micromirror layer 200, connecting the upper micromirror layer 200 and the lower support layer 100. This allows the micromirror platform 240 and the movable comb-tooth electrode 221 to be electrically connected to the lower support layer 100, thereby enabling signal extraction from below the support layer 100. Since the fixed comb-tooth electrode 121 is originally located on the lower support layer 100, the signal is usually extracted from below the support layer 100. As a result, the movable comb-tooth electrode 221, the micromirror platform 240, and the fixed comb-tooth electrode 121 can all be extracted from below the support layer 100. This allows signal circuits to be connected only below the support layer 100, rather than from both below the support layer 100 and above the micromirror layer 200 as in traditional structures. This simplifies the circuit extraction path, and single-sided extraction facilitates circuit layout, facilitating the miniaturized integrated packaging of the MEMS micromirror structure and other device structures. Furthermore, this structure requires a bonding-then-etching approach. Compared to the traditional method of etching first and then bonding, this process is less complex and does not require high-temperature treatment or the introduction of additional stress. This results in consistent device quality, making it suitable for mass production and a simple process.

[0045] Furthermore, in some embodiments of the present application:

[0046] The support layer 100 includes a lower frame 130 , and the micromirror layer 200 includes an upper frame 230 . The lower frame 130 and the upper frame 230 are bonded together via a bonding layer 300 .

[0047] The fixed block 120 is connected to the upper frame 230 via a bonding layer 300 and is spaced apart from the lower frame; the fixed comb electrode 121 is fixedly connected to the fixed block 120;

[0048] The connection blocks include an upper connection block 210 located on the micromirror layer 200 and a lower connection block 110 located on the support layer 100;

[0049] The lower connecting block 110 and the fixing block 120 are respectively connected to the upper frame 230 and are not electrically connected to each other;

[0050] The upper connecting block 210 is spaced apart from the upper frame 230 and connected to the torsion beam 220 ; the torsion beam 220 connects the micromirror platform 240 and the movable comb electrode 221 ;

[0051] The lower connecting block 110 is bonded to the upper connecting block 210 and the upper frame 230 through the bonding layer 300;

[0052] The connection metal layer 400 is located in the bonding layer 300 between the upper connection block 210 and the lower connection block 110 , and connects the upper connection block 210 and the lower connection block 110 , respectively.

[0053] The vertical comb-tooth MEMS micromirror structure provided in this embodiment is bonded to the upper frame 230 and the lower frame 130 via a bonding layer 300. The upper and lower connecting blocks 110 are connected to the torsion beam 220 and further connected to the micromirror platform 240 and the movable comb-tooth electrode 221, and the fixed block 120 and the fixed comb-tooth electrode 121. The connecting block and the fixed block 120 are not electrically connected to each other, so that the circuits of the micromirror platform 240 and the movable comb-tooth electrode 221 and the fixed comb-tooth electrode 121 are completely separated, and the leads on the same side will not interfere with each other.

[0054] Specifically, in some embodiments of the present application:

[0055] The torsion beam 220 extends along the first direction and is located at both ends of the micromirror platform 240 in the first direction;

[0056] The movable comb-tooth electrodes 221 are located on the sides of the torsion beam 220 on both sides of the micromirror platform 240 along the first direction and extend in the second direction;

[0057] The second direction is perpendicular to the first direction;

[0058] The fixed comb-tooth electrode 121 is located below the movable comb-tooth electrode 221 and is staggered with the movable comb-tooth electrode 221 along the first direction. The fixed comb-tooth electrode 121 is aligned with the gaps between adjacent teeth of the movable comb-tooth electrode 221.

[0059] The fixing blocks 120 are arranged at intervals along the second direction on both sides below the torsion beam 220 .

[0060] Furthermore, in some embodiments of the present application, the vertical comb-teeth MEMS micromirror structure further includes:

[0061] The mirror reflection layer 500 is located on the upper surface of the micromirror platform 240 (refer to Figure 30 );

[0062] The transfer layer 700 includes a transfer substrate 710 and a connecting through-hole 730 that passes through the transfer substrate 710 in the thickness direction; the transfer layer 700 also includes an insulating isolation layer 720 covering the upper surface, lower surface and inner wall of the connecting through-hole 730 of the transfer layer 700; the transfer layer 700 also includes an upper connection layer 740 on the upper surface of the insulating isolation layer 720 and a lower connection layer 750 of the insulating isolation layer 720; the remaining space filled with conductive metal in the connecting through-hole 730 connects the upper connection layer 740 and the lower connection layer 750; the lead-out layer 600 is located on the lower surface of the fixed block and the lower surface of the lower connecting block 110; the upper connection layer 740 is electrically connected to the lead-out layer 600 through the conductive connection structure M, and the lower connection layer 750 is connected to the ASIC chip 800 through the conductive connection structure M; the lower connection layer 750 is also connected to the substrate through the conductive connection structure M, and the ASIC chip 800 is located between the conductive connection structure M connected to the substrate.

[0063] The vertical comb-teeth MEMS micromirror structure provided in this embodiment can be connected to the ASIC chip 800 through the transfer layer 700. The ASIC chip 800 is placed under the overall structure and then connected to the substrate to achieve an integrated miniaturized packaging of the overall micromirror structure.

[0064] In some embodiments of the present application, the bonding layer 300 includes a first insulating layer 310 on the upper surface of the support layer 100 and a second insulating layer 320 on the lower surface of the micromirror layer 200, and a bonding metal layer 330 between the first insulating layer 310 and the second insulating layer 320; the bonding metal layer 330 is a patterned metal layer; the connecting metal layer 400 is connected to the bonding metal layer 330; the material of the support layer 100 and the micromirror layer 200 includes silicon; the material of the bonding metal layer 330 includes gold or copper; the connecting metal layer 400 is connected to the bonding metal layer 330; 0 includes gold or copper; the material of the first insulating layer 310 includes silicon dioxide; the material of the second insulating layer 320 includes silicon dioxide; the material of the mirror reflection layer 500 includes gold; the material of the lead-out layer 600 includes gold or copper; the material of the transfer substrate 710 includes silicon; the material of the insulating isolation layer 720 includes silicon dioxide; the material of the upper connection layer 740 includes gold or copper; the material of the lower connection layer 750 includes gold or copper; the material of the conductive metal includes gold or copper; and the conductive connection structure M includes a solder ball or a conductive bump.

[0065] Example 2

[0066] This embodiment provides a method for manufacturing a vertical comb-tooth MEMS micromirror structure. Figure 5 , including the following steps:

[0067] Providing an initial support layer 100 and an initial micromirror layer 200;

[0068] The initial support layer 100 and the initial micromirror layer 200 are bonded together via the bonding layer 300 and the connecting metal layer 400, wherein the bonding metal layer 330 penetrates the bonding layer 300 in the thickness direction, and the connecting metal layer 400 connects the support layer 100 and the micromirror layer 200;

[0069] Etching the initial micromirror layer 200 to complete patterning of the initial micromirror layer 200 to form the micromirror layer 200, which at least includes the micromirror platform 240 and the movable comb-tooth electrode 221; and electrically connecting the metal layer 400 and the movable comb-tooth electrode 221;

[0070] Etching the initial support layer 100 to complete patterning of the initial support layer 100 to form the support layer 100, which at least includes the fixed comb-tooth electrode 121;

[0071] Part of the bonding layer 300 is removed to complete the release of the micromirror platform 240 and the movable comb-tooth electrode 221 , and to prevent the connected structures of the fixed comb-tooth electrode 121 and the movable comb-tooth electrode 221 from being electrically connected to each other.

[0072] The method for manufacturing a vertical comb-tooth MEMS micromirror structure provided in this embodiment is suitable for manufacturing the vertical comb-tooth MEMS micromirror structure provided in this application. A connecting metal layer 400 is embedded in the bonding layer 300 between the support layer 100 and the micromirror layer 200, connecting the upper micromirror layer 200 and the lower support layer 100. This allows the micromirror platform 240 and the movable comb-tooth electrode 221 to be electrically connected to the lower support layer 100, thereby enabling signal extraction from below the support layer 100. Since the fixed comb-tooth electrode 121 is originally located on the supporting layer 100 below, the signal is usually led out from below the supporting layer 100. As a result, the movable comb-tooth electrode 221 and the micromirror platform 240 and the fixed comb-tooth electrode 121 can all be led out from below the supporting layer 100, and then the signal circuit can be connected only below the supporting layer 100, without having to lead out from two directions, namely, from below the supporting layer 100 and above the micromirror layer 200, as in the traditional structure. This simplifies the circuit lead-out path, and the single-sided lead-out makes it easier to arrange the circuit, which is conducive to the miniaturization and integrated packaging of the MEMS micromirror structure and other device structures. In addition, this structure requires a method of bonding first and then etching. Compared with the traditional method of etching separately first and then bonding, the process is less difficult and does not require high-temperature treatment or the introduction of additional stress. Therefore, the device quality is consistent, suitable for mass production, and the process is simple.

[0073] For further reference, Figure 6-15a and Figure 15b In some embodiments of the present application, the step of bonding the initial support layer 100 and the initial micromirror layer 200 via the bonding layer 300 and the connecting metal layer 400 includes:

[0074] Forming a first insulating layer 310 on one side of the initial supporting layer 100;

[0075] Patterning the first insulating layer 310 to form a first connection opening, exposing a portion of the initial supporting layer 100;

[0076] forming a first bonding metal layer 331 to cover the first insulating layer 310 and fill the first connection opening;

[0077] Forming a second insulating layer 320 on one side of the initial micromirror layer 200;

[0078] The second insulating layer 320 is patterned to form a second connection opening, exposing a portion of the initial micromirror layer 200; the second connection opening corresponds to the position of the first connection opening;

[0079] forming a second bonding metal layer 332 to cover the second insulating layer 320 and fill the second connection opening;

[0080] Bonding the initial support layer 100 and the initial micromirror layer 200 via the first bonding metal layer 331 and the second bonding metal layer 332;

[0081] The first bonding metal layer 331 and the second bonding metal layer 332 between the first insulating layer 310 and the second insulating layer 320 form a bonding metal layer 330 ;

[0082] At the same time, the first bonding metal layer 331 filling the first connection opening and the second bonding metal layer 332 filling the second connection opening are connected to form a connection metal layer 400;

[0083] In the step of etching the initial micromirror layer 200 , the first insulating layer 310 and the bonding metal layer 330 at corresponding positions are simultaneously etched and removed;

[0084] In the step of etching the initial support layer 100 , the second insulating layer 320 and the bonding metal layer 330 at corresponding positions are simultaneously etched and removed;

[0085] In the step of releasing the micromirror platform 240 and the movable comb-teeth electrode 221 , the portion of the remaining bonding layer 300 between the micromirror platform 240 and the movable comb-teeth and the supporting layer 100 is removed.

[0086] The method for manufacturing a vertical comb-tooth MEMS micromirror structure provided in this embodiment uses a bonding-first-then-etching approach, using a bonding layer 300 having a composite structure consisting of a first insulating layer 310, a bonding metal layer 330, and a second insulating layer 320 to provide support for the micromirror layer 200 during etching and isolate the micromirror layer 200 from the support layer 100. This prevents mutual interference during etching, ultimately removing unnecessary connecting portions to release the upper and lower layers. This eliminates the need for high-temperature or other stress-inducing processes, significantly reducing process difficulty.

[0087] A specific process is as follows:

[0088] Refer to the attached Figure 6 As shown:

[0089] 6-inch silicon (Si) was used as the initial support layer 100 and the initial micromirror layer 200. RCA standard cleaning was used. The substrate was placed in deionized water for cleaning and then dried to remove residual particles on the surface.

[0090] A first insulating layer 310 and a second insulating layer 320 are formed respectively, and SiO2 is deposited on the upper surfaces of the initial support layer 100 and the initial micromirror layer 200 respectively, with a thickness of 50-200 nm.

[0091] Refer to the attached Figure 7 As shown:

[0092] Using the spin coating process, the photoresist is dripped onto the silicon substrate surface, the photoresist is cured, the photomask array pattern is transferred to the silicon substrate, and then developed and cleaned. The photoresist opening size is adjusted according to the structural requirements.

[0093] The first insulating layer 310 and the second insulating layer 320 are patterned respectively, and SiO2 is etched to expose the underlying silicon.

[0094] A first bonding metal layer 331 and a second bonding metal layer 332 are formed respectively, and a metal layer is deposited to a thickness of 0.5 μm to 1 μm.

[0095] Refer to the attached Figure 8 As shown:

[0096] The initial support layer 100 and the initial micromirror layer 200 are bonded together via a first bonding metal layer 331 and a second bonding metal layer 332. The first bonding metal layer 331 and the second bonding metal layer 332 are then bonded together to form a bonding metal layer 330 and a connecting metal layer 400 by gold-gold hot-compression bonding. The temperature is 300-400°C and the pressure is 10 MPa-50 MPa.

[0097] Refer to the attached Figure 9 As shown:

[0098] A photoresist is spin-coated and patterned to serve as a mask for forming the mirror reflection layer 500 (the photoresist layer is not shown in the figure).

[0099] A metal layer is deposited on the upper surface of the top silicon layer using the patterned photoresist layer as a mask, with a thickness of 50nm to 200nm.

[0100] The photoresist layer and the metal layer on its surface are removed, and the remaining metal layer serves as the mirror reflection layer 500 .

[0101] Refer to the attached Figure 10 As shown:

[0102] The upper and lower surfaces are cleaned according to the RCA standard, and SiO2 and Si3N4 are grown on the upper and lower surfaces by PECVD as the hard mask base layer (D1) and hard mask surface layer (D2), respectively. The thickness of SiO2 is 200nm~500nm, and the thickness of Si3N4 is 2μm~5μm, which serve as the initial layer of deep silicon etching hard mask.

[0103] Refer to the attached Figure 11a and Figure 11b As shown:

[0104] A photoresist is spin-coated on the upper surface and patterned to serve as a mask for etching the hard mask on the upper surface (the photoresist layer is not shown in the figure).

[0105] Etch Si3N4 and SiO2 to make a deep silicon etching hard mask.

[0106] At this time corresponding Figure 1 The state at the AA section is as follows Figure 11a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 11b shown.

[0107] Refer to the attached Figure 12a and Figure 12b As shown:

[0108] Using the previously etched deep silicon etching hard mask (D1 and D2 on the upper side) as an etching mask, a deep silicon etching technique is used to etch the top silicon layer (i.e., the initial micromirror layer 200), completing the structure of the micromirror layer 200, including the movable comb electrode 221, the torsion beam 220, and the micromirror platform 240.

[0109] The exposed first insulating layer 310 and the bonding metal layer 330 thereunder are etched.

[0110] At this time corresponding Figure 1 The state at the AA section is as follows Figure 12a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 12b shown.

[0111] Refer to the attached Figure 13a and Figure 13b As shown:

[0112] The photoresist is spin-coated on the lower surface and patterned to serve as a mask for etching the hard mask on the lower surface (the photoresist layer is not shown in the figure).

[0113] Etch Si3N4 and SiO2 to make a deep silicon etching hard mask.

[0114] At this time corresponding Figure 1 The state at the AA section is as follows Figure 13a As shown, corresponding to Figure 1The state at the middle BB section is as follows Figure 13b shown.

[0115] Refer to the attached Figure 14a and Figure 14b As shown:

[0116] The aforementioned deep silicon etching hard mask (D1 and D2 on the lower side) is used as an etching mask, and the bottom silicon (ie, the initial support layer 100) is etched using deep silicon etching technology to complete the etching of structures such as the back cavity and the fixed comb electrode 121.

[0117] The exposed second insulating layer 320 and the bonding metal layer 330 thereunder are etched.

[0118] At this time corresponding Figure 1 The state at the AA section is as follows Figure 14a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 14b shown.

[0119] Refer to the attached Figure 15a and Figure 15b As shown:

[0120] The remaining exposed first insulating layer 310 and second insulating layer 320 are removed, and the portions above and below the insulating layer 320 shielded by silicon are not removed and are retained as the bonding layer 300. The exposed Si3N4 is removed and the micromirror layer 200 is released using VHF.

[0121] At this time corresponding Figure 1 The state at the AA section is as follows Figure 15a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 15b shown.

[0122] For further reference, Figure 16-24a and Figure 24b In some embodiments of the present application, the step of bonding the initial support layer 100 and the initial micromirror layer 200 via the bonding layer 300 and the connecting metal layer 400 includes:

[0123] Forming a first insulating layer 310 on one side of the initial supporting layer 100;

[0124] Patterning the first insulating layer 310 to form a first connection opening, exposing a portion of the initial supporting layer 100;

[0125] forming a first bonding metal layer 331 to cover the first insulating layer 310 and fill the first connection opening;

[0126] Patterning the first bonding metal layer 331 and removing the first bonding metal layer 331 corresponding to the portion of the first bonding metal layer 331 that is not connected between the support layer 100 and the micromirror layer 200 in the final structure;

[0127] Forming a second insulating layer 320 on one side of the initial micromirror layer 200;

[0128] Patterning the second insulating layer 320 to form a second connection opening to expose a portion of the initial micromirror layer 200;

[0129] The second connecting opening corresponds to the position of the first connecting opening;

[0130] forming a second bonding metal layer 332 to cover the second insulating layer 320 and fill the second connection opening;

[0131] The initial support layer 100 and the initial micromirror layer 200 are bonded together via the first bonding metal layer 331 and the second bonding metal layer 332. The remaining first bonding metal layer 331 between the first insulating layer 310 and the second insulating layer 320 forms the bonding metal layer 330. Meanwhile, the first bonding metal layer 331 filling the first connection opening and the second bonding metal layer 332 filling the second connection opening are correspondingly connected to form a connection metal layer 400.

[0132] In the step of etching the initial micromirror layer 200 , until the first insulating layer 310 is exposed;

[0133] In the step of etching the initial support layer 100 , until the second insulating layer 320 is exposed;

[0134] In the step of releasing the micromirror platform 240 and the movable comb-teeth electrodes 221 , the portions of the first insulating layer 310 and the second insulating layer 320 located between the micromirror platform 240 and the movable comb-teeth and the support layer 100 as well as the suspended portions are removed.

[0135] In the manufacturing method of a vertical comb-tooth MEMS micromirror structure provided in this embodiment, the bonding metal layer 330 in the bonding layer 300 is first patterned, and then etched until the insulating layer is exposed. This can further reduce the difficulty of etching. During the etching process, the insulating layer continues to provide support and isolation barriers for the upper and lower layers respectively, and finally removes the parts that need to be disconnected and blocked together. In this way, the two sides will not interfere with each other when etching. Although the process steps are slightly increased, only the step of patterning the metal layer is added first, the process difficulty is further reduced. There is no need to etch multiple layers in one step, which is beneficial for controlling the etching range, promoting the consistency of the device of the finished process, and facilitating mass production.

[0136] A specific process is as follows:

[0137] Refer to the attached Figure 6 As shown:

[0138] 6-inch silicon (Si) was used as the initial support layer 100 and the initial micromirror layer 200. RCA standard cleaning was used. The substrate was placed in deionized water for cleaning and then dried to remove residual particles on the surface.

[0139] A first insulating layer 310 and a second insulating layer 320 are formed respectively, and SiO2 is deposited on the upper surfaces of the initial support layer 100 and the initial micromirror layer 200 respectively, with a thickness of 50-200 nm.

[0140] Refer to the attached Figure 7 As shown:

[0141] Using the spin coating process, the photoresist is dripped onto the silicon substrate surface, the photoresist is cured, the photomask array pattern is transferred to the silicon substrate, and then developed and cleaned. The photoresist opening size is adjusted according to the structural requirements.

[0142] The first insulating layer 310 and the second insulating layer 320 are patterned respectively, and SiO2 is etched to expose the underlying silicon.

[0143] A first bonding metal layer 331 and a second bonding metal layer 332 are formed respectively, and a metal layer is deposited to a thickness of 0.5 μm to 1 μm.

[0144] Refer to the attached Figure 16 As shown:

[0145] The photoresist is spin-coated and patterned to serve as a mask for patterning the first bonding metal layer 331 and the second bonding metal layer 332 (the photoresist layer is not shown in the figure).

[0146] Using the patterned photoresist layer as a mask, the metal layers serving as the first bonding metal layer 331 and the second bonding metal layer 332 are etched to complete the patterning of the first bonding metal layer 331 and the second bonding metal layer 332 (a lift-off process may also be used to prepare patterned metal).

[0147] Refer to the attached Figure 17 As shown:

[0148] The initial support layer 100 and the initial micromirror layer 200 are bonded together via a first bonding metal layer 331 and a second bonding metal layer 332. Through gold-gold hot-compression bonding (gold-gold bonding requires the preparation of a flow guide groove if necessary), the first bonding metal layer 331 and the second bonding metal layer 332 together form a bonding metal layer 330 and a connecting metal layer 400. The temperature is 300-400°C and the pressure is 10 MPa-50 MPa. At this point, the bonding metal layer 330 is patterned. The patterned removal portion corresponds to the portion that will ultimately be removed at the corresponding location.

[0149] Refer to the attached Figure 18 As shown:

[0150] A photoresist is spin-coated and patterned to serve as a mask for forming the mirror reflection layer 500 (the photoresist layer is not shown in the figure).

[0151] A metal layer is deposited on the upper surface of the top silicon layer using the patterned photoresist layer as a mask, with a thickness of 50nm-200nm.

[0152] The photoresist layer and the metal layer on its surface are removed, and the remaining metal layer serves as the mirror reflection layer 500 .

[0153] Refer to the attached Figure 19 As shown:

[0154] The upper and lower surfaces are cleaned according to the RCA standard, and SiO2 and Si3N4 are grown on the upper and lower surfaces by PECVD as the hard mask base layer (D1) and hard mask surface layer (D2), respectively. The thickness of SiO2 is 200nm~500nm, and the thickness of Si3N4 is 2μm~5μm, which serve as the initial layer of deep silicon etching hard mask.

[0155] Refer to the attached Figure 20a and Figure 20b As shown:

[0156] A photoresist is spin-coated on the upper surface and patterned to serve as a mask for etching the hard mask on the upper surface (the photoresist layer is not shown in the figure).

[0157] Etch Si3N4 and SiO2 to make a deep silicon etching hard mask.

[0158] At this time corresponding Figure 1 The state at the AA section is as follows Figure 20a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 20b shown.

[0159] Refer to the attached Figure 21a and Figure 21b As shown:

[0160] Using the previously etched deep silicon etching hard mask (D1 and D2 on the upper side) as an etching mask, a deep silicon etching technique is used to etch the top silicon layer (i.e., the initial micromirror layer 200), completing the structure of the micromirror layer 200, including the movable comb electrode 221, the torsion beam 220, and the micromirror platform 240.

[0161] The etching is performed until the first insulating layer 310 is exposed.

[0162] At this time corresponding Figure 1 The state at the AA section is as follows Figure 21a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 21b shown.

[0163] Refer to the attached Figure 22a and Figure 22b As shown:

[0164] The photoresist is spin-coated on the lower surface and patterned to serve as a mask for etching the hard mask on the lower surface (the photoresist layer is not shown in the figure).

[0165] Etch Si3N4 and SiO2 to make a deep silicon etching hard mask.

[0166] At this time corresponding Figure 1 The state at the AA section is as follows Figure 22a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 22b shown.

[0167] Referring to Figure 23:

[0168] The aforementioned deep silicon etching hard mask (D1 and D2 on the lower side) is used as an etching mask, and the bottom silicon (ie, the initial support layer 100) is etched using deep silicon etching technology to complete the etching of structures such as the back cavity and the fixed comb electrode 121.

[0169] The etching is performed until the second insulating layer 320 is exposed.

[0170] At this time corresponding Figure 1 The state at the AA section is as follows Figure 23a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 23b shown.

[0171] Referring to Figure 24:

[0172] The remaining exposed first insulating layer 310 and second insulating layer 320 are removed, and the portions above and below the insulating layer 320 shielded by silicon are not removed and are retained as the bonding layer 300. The exposed Si3N4 is removed and the micromirror layer 200 is released using VHF.

[0173] At this time corresponding Figure 1 The state at the AA section is as follows Figure 24a As shown, corresponding to Figure 1 The state at the middle BB section is as follows Figure 24b shown.

[0174] Furthermore, in some embodiments of the present application, the method for manufacturing a vertical comb-teeth MEMS micromirror structure further includes the following steps:

[0175] refer to Figure 25, forming the transfer layer 700, including: providing an initial transfer substrate 710, forming a connection through hole 730 at a portion of a surface of one side of the initial transfer substrate 710; forming a third insulating layer on a surface of the initial transfer substrate 710 on a side where the connection through hole 730 opens, the third insulating layer also covering the inner wall of the connection through hole 730; filling the remaining space in the connection through hole 730 with a conductive metal; and forming a patterned upper connection layer 740 on a surface of the third insulating layer;

[0176] refer to Figure 26 , shielding one side of the upper connection layer 740 , thinning the side of the initial transfer substrate 710 opposite to the upper connection layer 740 to expose the connecting via 730 and slightly lower than the first insulating layer 310 and the conductive metal in the conductive via;

[0177] refer to Figure 27 A fourth insulating layer is formed on the surface of the initial transfer substrate 710 opposite to the upper connection layer 740, and the fourth insulating layer is connected to the third insulating layer to form an isolation insulating layer; a patterned lower connection layer 750 is formed on the surface of the fourth insulating layer;

[0178] The method for manufacturing a vertical comb-teeth MEMS micromirror structure further includes the following steps:

[0179] refer to Figure 28 , bonding the ASIC chip 800 to the lower connection layer 750 through the conductive connection structure M;

[0180] refer to Figure 29 , bonding the transfer substrate 710 to the substrate via the conductive connection structure M;

[0181] refer to Figure 30 A patterned lead-out layer 600 is formed on the surface of the support layer 100 facing away from the micromirror layer 200 , and the lead-out layer 600 is located on the surface of the portion conductive to the movable comb-tooth electrode 221 and the surface of the portion conductive to the fixed comb-tooth electrode 121 ;

[0182] The bonded support layer 100 and micromirror layer 200 are bonded to the transfer layer 700 through the lead-out layer 600 and the conductive connection structure M, and connected to the upper connection layer 740 .

[0183] The manufacturing method of the vertical comb-tooth MEMS micromirror structure provided in this embodiment connects the ASIC chip 800 on one side by forming a transfer layer 700 and integrally packages it to the substrate, thereby realizing an integrated miniaturized packaging of the vertical comb-tooth MEMS micromirror structure.

[0184] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of this application.

Claims

1. A vertical comb-teeth MEMS micromirror structure, characterized in that: include: A support layer and a micromirror layer, wherein the support layer includes a fixed comb-tooth electrode, and the micromirror layer includes a micromirror platform and a movable comb-tooth electrode; The fixed comb-tooth electrode and the movable comb-tooth electrode are arranged in a staggered manner; a bonding layer, located between the support layer and the micromirror layer, connecting the support layer and the micromirror layer; a connecting metal layer, penetrating the bonding layer in a thickness direction, the connecting metal layer connecting the supporting layer and the micromirror layer, and being electrically conductive with the movable comb-tooth electrode; The MEMS micromirror structure also includes a fixed block located on the supporting layer and a connecting block located on the supporting layer and the micromirror layer. The fixed comb-tooth electrode is suitable for leading out signals to the bottom of the supporting layer through the fixed block connected to itself; the movable comb-tooth electrode is suitable for leading out signals to the bottom of the supporting layer through the connecting metal layer and the connecting block.

2. The vertical comb-teeth MEMS micromirror structure according to claim 1, characterized in that: The support layer includes a lower frame, the micromirror layer includes an upper frame, and the lower frame and the upper frame are bonded to each other via the bonding layer; The fixed block is connected to the upper frame through the bonding layer and is spaced apart from the frame; the fixed comb-tooth electrode is fixedly connected to the fixed block; The connecting blocks include an upper connecting block located on the micromirror layer and a lower connecting block located on the support layer; The lower connecting block and the fixing block are respectively connected to the upper frame and are not electrically connected to each other; The upper connecting block is spaced apart from the upper frame and connected to a torsion beam; the torsion beam connects the micromirror platform and the movable comb electrode; The lower connecting block is bonded to the upper connecting block and the upper frame through the bonding layer respectively; the connecting metal layer is located in the bonding layer between the upper connecting block and the lower connecting block, and connects the upper connecting block and the lower connecting block respectively.

3. The vertical comb-teeth MEMS micromirror structure according to claim 2, characterized in that: The torsion beam extends along a first direction and is located at both ends of the micromirror platform in the first direction; The movable comb-tooth electrodes are located on the sides of the torsion beam on both sides of the micromirror platform along the first direction and extend in the second direction; The second direction is perpendicular to the first direction; The fixed comb-tooth electrode is located below the movable comb-tooth electrode and is staggered with the movable comb-tooth electrode along the first direction, and the fixed comb-tooth electrode is aligned with the gaps between adjacent teeth of the movable comb-tooth electrode; The fixing blocks are located on both sides below the torsion beam and are arranged at intervals along the second direction.

4. The vertical comb-teeth MEMS micromirror structure according to claim 3, characterized in that: Also includes: A mirror reflection layer is located on the upper surface of the micromirror platform; A transfer layer, the transfer layer comprising a transfer substrate and a connecting through-hole penetrating the transfer substrate in a thickness direction; The transfer layer further includes an insulating isolation layer covering the upper surface and lower surface of the transfer layer and the inner wall of the connecting through hole; the transfer layer further includes an upper connection layer on the upper surface of the insulating isolation layer and a lower connection layer of the insulating isolation layer; the connecting through hole is filled with a conductive metal to connect the upper connection layer and the lower connection layer; a lead-out layer, the lead-out layer being located on the lower surface of the fixing block and the lower surface of the lower connecting block; The upper connection layer is electrically connected to the lead-out layer via a conductive connection structure, and the lower connection layer is connected to the ASIC chip via a conductive connection structure; The lower connection layer is further connected to the substrate via a conductive connection structure, and the ASIC chip is located between the conductive connection structures connected to the substrate.

5. The vertical comb-teeth MEMS micromirror structure according to claim 4, characterized in that: The bonding layer includes a first insulating layer on the upper surface of the supporting layer and a second insulating layer on the lower surface of the micromirror layer, and a bonding metal layer between the first insulating layer and the second insulating layer; the bonding metal layer is a patterned metal layer; and the connecting metal layer is connected to the bonding metal layer.

6. The vertical comb-teeth MEMS micromirror structure according to claim 5, characterized in that: The materials of the support layer and the micromirror layer include silicon; The material of the bonding metal layer is gold, and the material of the connecting metal layer includes gold or copper; The material of the first insulating layer includes silicon dioxide; the material of the second insulating layer includes silicon dioxide; The material of the mirror reflection layer includes gold; the material of the lead-out layer includes gold or copper; The material of the transfer substrate includes silicon; the material of the insulating isolation layer includes silicon dioxide; the material of the upper connection layer includes gold or copper; the material of the lower connection layer includes gold or copper; the material of the conductive metal includes gold or copper; The conductive connection structure includes a solder ball or a conductive bump.

7. A method for manufacturing a vertical comb-teeth MEMS micromirror structure, characterized in that: The following steps are involved: providing an initial support layer and an initial micromirror layer; Bonding the initial support layer and the initial micromirror layer via a bonding layer and a connecting metal layer, wherein the connecting metal layer penetrates the bonding layer in a thickness direction, and the connecting metal layer connects the support layer and the micromirror layer; Etching the initial micromirror layer to complete patterning of the initial micromirror layer to form a micromirror layer, which at least includes a micromirror platform and a movable comb-tooth electrode; the connecting metal layer is electrically connected to the movable comb-tooth electrode; Etching the initial support layer to complete patterning of the initial support layer to form a support layer comprising at least a fixed comb-tooth electrode; Part of the bonding layer is removed to complete the release of the micromirror platform and the movable comb-tooth electrode, and to prevent the structures connected to the fixed comb-tooth electrode and the movable comb-tooth electrode from being electrically connected to each other.

8. The method for manufacturing a vertical comb-teeth MEMS micromirror structure according to claim 7, characterized in that: The step of bonding the initial support layer and the initial micromirror layer via a bonding layer and a connecting metal layer comprises: forming a first insulating layer on a surface of one side of the initial supporting layer; Patterning the first insulating layer to form a first connection opening, exposing a portion of the initial supporting layer; forming a first bonding metal layer to cover the first insulating layer and fill the first connection opening; forming a second insulating layer on a surface of one side of the initial micromirror layer; Patterning the second insulating layer to form a second connection opening to expose a portion of the initial micromirror layer; the second connection opening corresponds to a position of the first connection opening; forming a second bonding metal layer to cover the second insulating layer and fill the second connection opening; The initial support layer and the initial micromirror layer are bonded together via the first bonding metal layer and the second bonding metal layer; the first bonding metal layer and the second bonding metal layer between the first insulating layer and the second insulating layer form a bonding metal layer; and the first bonding metal layer filling the first connection opening and the second bonding metal layer filling the second connection opening are correspondingly connected to form the connection metal layer; In the step of etching the initial micromirror layer, the first insulating layer and the bonding metal layer at corresponding positions are simultaneously etched and removed; In the step of etching the initial support layer, the second insulating layer and the bonding metal layer at corresponding positions are simultaneously etched and removed; In the step of releasing the micromirror platform and the movable comb-teeth electrodes, the remaining bonding layer portion between the micromirror platform and the movable comb-teeth and the supporting layer is removed.

9. The method for manufacturing a vertical comb-teeth MEMS micromirror structure according to claim 7, characterized in that: The step of bonding the initial support layer and the initial micromirror layer via a bonding layer and a connecting metal layer comprises: forming a first insulating layer on a surface of one side of the initial supporting layer; Patterning the first insulating layer to form a first connection opening, exposing a portion of the initial supporting layer; forming a first bonding metal layer to cover the first insulating layer and fill the first connection opening; Patterning the first bonding metal layer, and removing the first bonding metal layer corresponding to the portion of the final structure that is not connected between the support layer and the micromirror layer; forming a second insulating layer on a surface of one side of the initial micromirror layer; Patterning the second insulating layer to form a second connection opening to expose a portion of the initial micromirror layer; the second connection opening corresponds to a position of the first connection opening; forming a second bonding metal layer in the second connection opening; The initial support layer and the initial micromirror layer are bonded together via the first bonding metal layer and the second bonding metal layer; the first bonding metal layer remaining between the first insulating layer and the second insulating layer forms a bonding metal layer; and the first bonding metal layer filling the first connection opening and the second bonding metal layer filling the second connection opening are correspondingly connected to form the connection metal layer; In the step of etching the initial micromirror layer, the first insulating layer is exposed; In the step of etching the initial support layer, the second insulating layer is exposed; In the step of releasing the micromirror platform and the movable comb-teeth electrodes, portions of the first insulating layer and the second insulating layer located between the micromirror platform and the movable comb-teeth and the supporting layer, as well as suspended portions, are removed.

10. The method for manufacturing a vertical comb-teeth MEMS micromirror structure according to claim 7, wherein: The following steps are also included: Forming the transfer layer includes: providing an initial transfer substrate, and forming a connecting through hole at a portion of a surface of one side of the initial transfer substrate; forming a third insulating layer on a surface of one side of the opening of the initial transfer substrate connecting through hole, wherein the third insulating layer also covers the inner wall of the connecting through hole; Filling the remaining space in the connecting through hole with a conductive metal; forming a patterned upper connection layer on the surface of the third insulating layer; Thinning the side of the initial transfer substrate opposite to the upper connection layer until the connection through hole is exposed; forming a fourth insulating layer on the surface of the initial transfer substrate opposite to the upper connection layer, wherein the fourth insulating layer is integrally connected with the third insulating layer to form an isolation insulating layer; forming a patterned lower connection layer on the surface of the fourth insulating layer; The method for manufacturing the vertical comb-teeth MEMS micromirror structure further comprises the following steps: bonding the ASIC chip to the lower connection layer via a conductive connection structure; Bonding the transfer substrate to the substrate via a conductive connection structure; A patterned lead-out layer is formed on a surface of the support layer facing away from the micromirror layer, wherein the lead-out layer is located on a surface of a portion conductive to the movable comb-tooth electrode and a surface of a portion conductive to the fixed comb-tooth electrode; The bonded support layer and the micromirror layer are bonded to the transfer layer through the lead-out layer and the conductive connection structure, and connected to the upper connection layer.

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