An ASIC-MEMS micromirror integrated device and a preparation method thereof

Abstract

This invention discloses an ASIC-MEMS micromirror integrated device and its fabrication method, which improves product performance. This invention achieves direct bonding and interconnection between the MEMS micromirror and the ASIC driver control chip pads by first bonding the ASIC driver control chip to a solid silicon wafer of the MEMS micromirror, then fabricating a fixed comb-tooth structure layer, and finally releasing the movable structure layer. This enables high-voltage direct drive. Simultaneously, the bonding pressure is applied to the rigid solid silicon wafer, completely solving the problem of bonding pressure damaging the movable microbeam in traditional solutions, and completely eliminating the drawbacks of the TSV transition layer, significantly improving product yield and performance.

Description

Technical Field

[0001] This invention relates to the field of MEMS sensor technology, and in particular to an integrated device and fabrication method of a MEMS micromirror and an ASIC driving control chip. Background Technology

[0002] Existing integration solutions for MEMS micromirrors and ASIC driver control chips are suitable for MEMS devices such as lidar and optical scanning that require high-voltage direct drive, miniaturization, and high reliability. They generally use TSV (Through Silicon Via) adapter layers to achieve signal output from MEMS micromirrors and interconnection with ASIC driver control chips. The typical structure, from top to bottom, consists of: a MEMS movable structure layer including moving comb teeth and micromirror beams, a MEMS fixed comb tooth layer, a TSV adapter layer, and an ASIC driver control chip.

[0003] The traditional approach requires the additional fabrication of a TSV interposer layer, employing multiple complex processes such as deep silicon etching, TSV insulation, seed layer deposition, electroplating filling, and back-side thinning. This process is cumbersome, makes it difficult to control product yield, and significantly increases production costs. Signal transmission must pass through comb teeth, wiring, and the TSV interposer layer before reaching the ASIC driver control chip. This long signal transmission path, coupled with parasitic inductance and resistance, leads to voltage drop in the high-voltage drive signal and deterioration in high-frequency response, thus limiting electrical performance and affecting the stability of micromirror scanning. Furthermore, the traditional approach involves fabricating the MEMS movable structure, such as the micromirror beam and comb teeth, before bonding. The bonding pressure can easily cause deformation, adhesion, or breakage of the movable structure, such as the micromirror beam, reducing device yield. The TSV interposer layer increases the overall thickness of the device, hindering miniaturization and making it unsuitable for size-sensitive applications such as automotive LiDAR. The TSV interposer layer itself is prone to failure modes such as voids, stress cracking, and leakage, and the additional bonding interface further increases the overall failure probability of the device.

[0004] In summary, there is an urgent need for a new integration solution for MEMS micromirrors and ASIC drive control chips that can improve performance and avoid damage to movable structures. Summary of the Invention

[0005] This invention provides an ASIC-MEMS micromirror integrated device and its fabrication method, which simplifies the structure of the ASIC-MEMS micromirror integrated device, improves its performance, and increases the yield.

[0006] This invention provides a method for fabricating an ASIC-MEMS micromirror integrated device, comprising: ASIC driver control chip processing steps: A passivation protection layer is prepared on the surface of the ASIC driver control chip to achieve internal metal interconnection and device structure protection; windows and holes are opened on the passivation protection layer, and the areas of the windows and holes correspond to the positions of the high voltage lead-out pads and ground lead-out pads of the ASIC driver control chip. Metal thin film deposition and patterning processes are performed, and bonding connection anchors for the high voltage lead-out pads and ground lead-out pads of the ASIC driver control chip are prepared in the areas of the windows and holes; Solid silicon wafer processing steps for the fixed comb tooth structure layer: Metal thin film deposition and patterning process is performed on the solid silicon wafer of the fixed comb tooth structure layer. Corresponding electrode point bonding anchors and ground pad bonding anchors are prepared at the positions of the lead-out electrode points of each fixed comb tooth and the corresponding ASIC driver control chip ground lead-out pads, respectively, for conducting the drive signal of the ASIC driver control chip after gold-gold bonding. The first gold-to-gold bonding layer processing steps are as follows: the bonding anchor points of the high voltage lead-out pads and the bonding anchor points of the ground lead-out pads of the ASIC driver control chip are respectively bonded to the electrode point bonding anchor points and the ground pad bonding anchor points on the solid silicon wafer of the fixed comb structure layer to form the first gold-to-gold bonding layer. The steps for fabricating the fixed comb tooth structure layer are as follows: Remove the substrate layer and silicon dioxide insulating layer of the solid silicon wafer of the fixed comb tooth structure layer, retaining the device layer. Perform metal thin film deposition and photolithography patterning on the front side of the device layer, retaining the grounding metal anchor points for docking the moving comb teeth. Perform photolithography and silicon etching on the front side of the device layer to create fixed comb tooth electrode grooves and form the fixed comb tooth body structure. Fabricate ground interconnect silicon pillars to conduct the grounding pads of the first gold-to-gold bonding layer and the second gold-to-gold bonding layer, forming a complete fixed comb tooth structure layer. The fixed comb tooth electrodes extend downward along the electrode grooves to the first gold-to-gold bonding layer, and are connected to the ASIC driver control chip via electrode point bonding anchor points. The second gold-to-gold bonding layer processing steps are as follows: metal thin film deposition and patterning processes are performed on the solid silicon wafer of the moving comb tooth structure layer to prepare grounding metal anchor points that are connected to the fixed comb teeth. The grounding metal anchor points connected to the moving comb teeth and the grounding metal anchor points connected to the fixed comb teeth are then bonded together to prepare the second gold-to-gold bonding layer. The steps for fabricating the moving comb tooth structure layer are as follows: Remove the substrate layer and silicon dioxide insulating layer of the solid silicon wafer of the moving comb tooth structure layer, retain the device layer, perform photolithography and silicon etching on the device layer, fabricate the micromirror body, micromirror beam and moving comb teeth that match the fixed comb teeth, form the moving comb tooth structure layer, and complete the fabrication of the ASIC-MEMS micromirror integrated device.

[0007] In a preferred embodiment, a wafer containing multiple ASIC-MEMS micromirror integrated devices is diced to obtain a single ASIC-MEMS micromirror integrated device.

[0008] In a preferred embodiment, an annular metal bonding ring is prepared around the periphery of the first gold-gold bonding layer to enhance the bonding strength of the bonding interface; and / or, an annular metal bonding ring is prepared around the periphery of the second gold-gold bonding layer to enhance the bonding strength of the bonding interface.

[0009] In a preferred embodiment, annular metal bonding rings are fabricated around the periphery of the solid silicon wafers of the ASIC driver control chip and the fixed comb tooth structure layer, respectively, and gold-to-gold bonding is performed during the first gold-to-gold bonding layer treatment to fabricate the annular metal bonding ring of the first gold-to-gold bonding layer; and / or, annular metal bonding rings are fabricated around the periphery of the fixed comb tooth structure layer during the fabrication of the fixed comb tooth structure layer, and annular metal bonding rings are fabricated around the periphery of the solid silicon wafers of the moving comb tooth structure layer, and gold-to-gold bonding is performed during the second gold-to-gold bonding layer treatment to fabricate the annular metal bonding ring of the second gold-to-gold bonding layer.

[0010] In a preferred embodiment, the gold-to-gold bonding control conditions for preparing the first gold-to-gold bonding layer and the second gold-to-gold bonding layer are both: temperature controlled at 200-250℃, and ≤10℃. - A vacuum environment of 3Pa and pressure control between 7000mbar±500mbar ensure that the bonding interface is free of voids, achieving a tight bond, while avoiding high temperature damage to the ASIC driver control chip.

[0011] In a preferred embodiment, the bonding metals for preparing the first gold-gold bonding layer and the second gold-gold bonding layer are any of Au, Cu, Pt, and Ti / Au composite materials; the bonding process is any of hot-pressing bonding, low-temperature plasma activation bonding, and Au-Sn eutectic bonding.

[0012] In a preferred embodiment, the moving comb teeth are driven by comb teeth, a planar capacitor, or a torsion beam.

[0013] In a preferred embodiment, a contact through-hole or shallow etched window is formed at the bottom of the comb teeth to reduce contact resistance.

[0014] In a preferred embodiment, the annular metal bonding ring employs a multilayer metal stack.

[0015] In a preferred embodiment, when fabricating the fixed comb tooth structure layer, the overall fixed comb tooth structure is divided into four independent fixed comb tooth functional regions. The high voltage lead-out bonding pads of the ASIC driver control chip are bonded to anchor points and are set one-to-one with the fixed comb tooth electrodes. Each fixed comb tooth functional region corresponds to a deflection direction of the micromirror and is used to drive the deflection angle of the micromirror in the corresponding direction.

[0016] This invention also provides an integrated device for an ASIC-MEMS micromirror manufactured using the above-described preparation method.

[0017] This invention employs a sequence of first bonding the ASIC driver control chip to the solid silicon wafer of the MEMS micromirror, then fabricating the fixed comb tooth structure layer, and finally releasing the movable structure layer. This sequence applies bonding pressure to the rigid solid silicon wafer, completely solving the problem of bonding pressure damaging the movable microbeam in traditional solutions and significantly improving product yield. The fixed comb tooth electrodes of the MEMS micromirror are directly interconnected with the pads of the ASIC driver control chip via gold-to-gold bonding, achieving high-voltage direct drive. This simplifies the device structure, reduces thickness, and completely overcomes the drawbacks of TSV adapter layers and adapter boards, wire bonding, or ball bonding processes. Through two gold-to-gold bonding operations, the electrical connection and mechanical fixation between the MEMS micromirror and the ASIC driver control chip are achieved in one step, simplifying the process flow. Furthermore, it directly applies high-voltage signals from the ASIC driver control chip to the fixed comb tooth through the gold-to-gold bonding layer, eliminating the need for intermediate adapter layers and long traces. This significantly reduces parasitic inductance and resistance, resulting in better high-frequency response and higher driving efficiency. Attached Figure Description

[0018] Figure 1 This is the fabrication method of the ASIC-MEMS micromirror integrated device according to Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the ASIC-MEMS micromirror integrated device according to Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the micromirrors in the ASIC-MEMS micromirror integration device according to Embodiment 2 of the present invention; Figure 4 This is a schematic diagram of the upper surface of the ASIC drive control chip of the ASIC-MEMS micromirror integrated device according to Embodiment 2 of the present invention. Detailed Implementation

[0019] The following is in conjunction with the appendix Figure 1 Appendix Figure 2 Appendix Figure 3 and attached Figure 4 The specific implementation method of the fabrication method of the ASIC-MEMS micromirror integrated device provided in Embodiment 1 of the present invention will be described in detail.

[0020] Embodiment 1 of the present invention provides a method for fabricating an ASIC-MEMS micromirror integrated device, comprising: ASIC driver control chip processing steps: A passivation protection layer S2 is prepared on the surface of the ASIC driver control chip S1 to realize internal metal interconnection and device structure protection; windows and holes are opened on the passivation protection layer S2, and the areas of the windows and holes correspond to the positions of the high voltage lead-out pads and ground lead-out pads of the ASIC driver control chip S1. Metal thin film deposition and patterning processes are performed; bonding connection anchors S51 for the high voltage lead-out pads and bonding connection anchors S31 for the ground lead-out pads of the ASIC driver control chip S1 are prepared in the areas of the windows and holes. The solid silicon wafer processing steps for the fixed comb tooth structure layer are as follows: Metal thin film deposition and patterning processes are performed on the solid silicon wafer of the fixed comb tooth structure layer. Corresponding electrode bonding anchors S52 and grounding pad bonding anchors S32 are prepared at the lead-out electrode points of each fixed comb tooth and the corresponding ASIC driver control chip ground lead-out pads, respectively, for conducting the drive signal of the ASIC driver control chip after gold-gold bonding; this forms the lead-out electrode bonding pads of the fixed comb tooth and the grounding pads of the fixed comb tooth layer. The first gold-to-gold bonding layer processing steps are as follows: The bonding anchor points S51 of the high-voltage lead-out pad and S31 of the ground lead-out pad of the ASIC driver control chip S1 are bonded to the electrode point bonding anchor points S52 and the ground pad bonding anchor points S32 on the solid silicon wafer of the fixed comb structure layer, respectively, to form the first gold-to-gold bonding layer; in this way, the first gold-to-gold bonding layer forms the electrode pads of the fixed comb and the ground pads of the fixed comb layer, which respectively realize the power supply drive connection and ground pin connection of the ASIC driver control chip S1. The steps for fabricating the fixed comb tooth structure layer are as follows: Remove the substrate layer and silicon dioxide insulating layer of the solid silicon wafer of the fixed comb tooth structure layer, retaining the device layer. Perform metal thin film deposition and photolithography patterning on the front side of the device layer, retaining the grounding metal anchor point S91 for docking the moving comb tooth; perform photolithography and silicon etching on the front side of the device layer, groove to prepare the fixed comb tooth electrode groove and form the fixed comb tooth S7 body structure, and prepare the ground interconnect silicon pillar S6 to conduct the grounding pad of the first gold bonding layer and the second gold bonding layer, forming a complete fixed comb tooth structure layer; the fixed comb tooth electrode extends downward along the electrode groove to the first gold bonding layer, and is connected to the ASIC driver control chip S1 via the electrode point bonding anchor point S52. The second gold-to-gold bonding layer processing steps are as follows: a metal thin film deposition and patterning process is performed on the solid silicon wafer of the moving comb tooth structure layer to prepare the grounding metal anchor point S92 that is connected to the fixed comb tooth. The grounding metal anchor point S91 connected to the moving comb tooth and the grounding metal anchor point S92 connected to the fixed comb tooth are gold-to-gold bonded to prepare the second gold-to-gold bonding layer. The steps for fabricating the moving comb tooth structure layer are as follows: Remove the substrate layer and silicon dioxide insulating layer of the solid silicon wafer containing the moving comb tooth structure layer, retaining the device layer. Perform photolithography and silicon etching on this device layer to fabricate the micromirror body S11, the micromirror beam, and the moving comb teeth S10 that match the fixed comb teeth, forming the moving comb tooth structure layer and completing the fabrication of the ASIC-MEMS micromirror integrated device. The fabrication of the moving comb tooth structure layer is as follows: Figure 3 As shown.

[0021] Of course, when the final wafer contains multiple individual ASIC-MEMS micromirror integrated devices, it needs to be diced to obtain a single ASIC-MEMS micromirror integrated device.

[0022] To enhance the bonding strength of the bonding interface between the ASIC driver control chip S1 and the fixed comb structure layer, an annular metal bonding ring is fabricated around the periphery of the first gold-gold bonding layer. Specifically, the fabrication method is as follows: a lower half of the annular metal bonding ring S41 is fabricated around the periphery of the ASIC driver control chip S1, and an upper half of the annular metal bonding ring S42 is fabricated around the periphery of the solid silicon wafer of the fixed comb structure layer. During the processing of the first gold-gold bonding layer, the upper and lower half of the annular metal bonding rings S42 and S41 are bonded together to form the annular metal bonding ring of the first gold-gold bonding layer. Similarly, to enhance the bonding strength at the bonding interface between the fixed comb tooth structure layer and the moving comb tooth structure layer, an annular metal bonding ring is fabricated around the periphery of the second gold-gold bonding layer. Specifically, during the fabrication of the fixed comb tooth structure layer, a lower half of the annular metal bonding ring S81 is fabricated around its periphery, and an upper half of the annular metal bonding ring S82 is fabricated around the periphery of the solid silicon wafer of the moving comb tooth structure layer. During the processing of the second gold-gold bonding layer, the upper and lower halves of the annular metal bonding rings S82 and S81 are gold-bonded to fabricate the annular metal bonding ring of the second gold-gold bonding layer. The annular metal bonding ring is fabricated using multilayer metal stacking.

[0023] The ASIC-MEMS micromirror integrated device of Embodiment 2 of the present invention was fabricated using the fabrication method of the ASIC-MEMS micromirror integrated device provided in Embodiment 1 of the present invention. Figure 2 As shown, a four-layer integrated structure is formed from top to bottom, with two gold-to-gold bonding layers at the core and three functional layers. The TSV direct connection has been removed, as detailed below: Micromirror moving comb structure layer: including moving comb S10, micromirror beam, and micromirror body S11. This structure layer is a movable structure formed at the end of the fabrication process, realizing one-dimensional or two-dimensional scanning motion under electrostatic drive. The second gold-to-gold bonding layer is a grounding pad formed by grounding metal anchor points connecting the moving comb structure layer and the fixed comb structure layer of the micromirror, realizing electrical conduction between the moving comb structure layer and the ASIC driver control chip S1; it also has an annular metal bonding ring around the periphery of the second gold-to-gold bonding layer to enhance the bonding strength of the bonding interface between the fixed comb structure layer and the moving comb structure layer. Micromirror fixed comb tooth structure layer: including fixed comb tooth S7, fixed comb tooth electrode, and ground interconnect silicon pillar S6; the fixed comb tooth electrode extends downward and directly contacts the first gold bonding layer to achieve direct connection with the electrode of ASIC driver control chip S1; The first gold-to-gold bonding layer has a ground pad for connecting the ground interconnect silicon pillar S6 of the micromirror comb structure layer and the ground pin of the ASIC driver control chip S1; an electrode pad connecting the comb electrode of the micromirror comb structure layer and the high-voltage output pad of the ASIC driver control chip S1, and the ground pad and the electrode pad realize the electrical conduction between the micromirror and the ASIC driver control chip S1; and an annular metal bonding ring around the periphery of the first gold-to-gold bonding layer to enhance the bonding strength of the bonding interface between the comb structure layer and the ASIC driver control chip S1. The ASIC driver control chip features a high-voltage drive circuit, high-voltage output pads, a ground pin, and a passivation protection layer S3. The high-voltage output pads correspond one-to-one with the fixed comb electrode, and the high-voltage drive signal is directly applied through the first gold-to-gold bonding layer. The final fabricated ASIC driver control chip of the ASIC-MEMS micromirror integrated device of Embodiment 2 of this invention has the following upper surface... Figure 4 As shown.

[0024] The gold-to-gold bonding control conditions for preparing the first and second gold-to-gold bonding layers are as follows: temperature controlled at 200-250℃, ≤10 ℃. - A vacuum environment of 3Pa and pressure control between 7000mbar±500mbar ensures a void-free bonding interface and a tight bond. This also effectively prevents high-temperature damage to the ASIC driver control chip. The bonding metal is preferably any of Au, Cu, Pt, and Ti / Au composite materials; the bonding process can be any of hot-press bonding, low-temperature plasma activation bonding, and Au-Sn eutectic bonding.

[0025] When fabricating the fixed comb tooth structure layer, the overall fixed comb tooth structure is divided into four independent fixed comb tooth functional regions. The high-voltage lead-out pads of the ASIC driver control chip are bonded to anchor points that correspond one-to-one with the fixed comb tooth electrodes. Each fixed comb tooth functional region corresponds to a deflection direction of the micromirror, driving the micromirror in the corresponding direction to achieve the deflection angle. For example... Figure 4As shown, after power is supplied through the power supply connection point on the outside of the ASIC driver control chip, the ASIC driver control chip provides the corresponding voltage to the stationary comb electrode in the corresponding direction according to the required direction and angle of micromirror deflection, thereby realizing the angle deflection of the micromirror.

[0026] When preparing the moving comb tooth structure layer, the driving form of the moving comb tooth can be made into a comb tooth drive, a planar capacitor drive, or a torsion beam drive, depending on the needs of different products.

[0027] To prepare a fixed comb tooth structure layer, contact through holes or shallow etched windows are opened at the bottom of the fixed comb teeth to better reduce contact resistance.

[0028] The integrated device of ASIC-MEMS micromirror manufactured according to the preparation method of Embodiment 1 of the present invention is also within the scope of the present invention.

[0029] The embodiments of this invention employ a sequence of first bonding the ASIC driver control chip and the MEMS micromirror solid silicon wafer, then fabricating the fixed comb tooth structure layer, and finally releasing the movable structure layer, resulting in significant technical advantages: Simplified process and reduced cost: Completely eliminates TSV interposer layer and interposer board, wire bonding or ball bonding processes, reduces the number of wafer layers and bonding times, reduces the number of processes by more than 30%, reduces production costs by 20%-40%, and increases product yield by more than 15%. No damage to movable structures: The bonding process is completed before the movable structure is fabricated. The bonding pressure is applied to the solid silicon wafer, which completely avoids the deformation and breakage of the movable microbeams and comb teeth, solving the core yield pain point of traditional solutions. Excellent electrical performance: The shortest high-voltage direct drive path, no parasitic loss, and more stable signal transmission enable higher micromirror scanning frequency and faster response, making it better suited for high-frequency and high-voltage drive scenarios. Miniaturization: By removing the TSV adapter layer, the overall thickness of the integrated device is reduced by 30%-50%, making it more suitable for size-sensitive applications such as automotive LiDAR and small optical scanning modules. Improved reliability: By abandoning the TSV through-hole structure, the potential for through-hole failure is completely avoided. At the same time, the overall bonding process is reduced, which greatly improves the long-term reliability and operational stability of the device.

[0030] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for fabricating an ASIC-MEMS micromirror integrated device, characterized in that: ASIC driver control chip processing steps: A passivation protection layer is prepared on the surface of the ASIC driver control chip to realize internal metal interconnection and device structure protection; windows and holes are opened on the passivation protection layer, and the areas of the windows and holes correspond to the positions of the high voltage lead-out pads and ground lead-out pads of the ASIC driver control chip. Metal thin film deposition and patterning processes are performed, and bonding connection anchors for the high voltage lead-out pads and ground lead-out pads of the ASIC driver control chip are prepared in the areas of the windows and holes; Solid silicon wafer processing steps for the fixed comb tooth structure layer: Metal thin film deposition and patterning process is performed on the solid silicon wafer of the fixed comb tooth structure layer. Corresponding electrode point bonding anchors and ground pad bonding anchors are prepared at the lead-out electrode points of each fixed comb tooth and the corresponding ground lead-out pads of the ASIC driver control chip, respectively, for conducting the drive signal of the ASIC driver control chip after gold bonding. First gold-to-gold bonding layer processing steps: The bonding connection anchor points of the high voltage lead-out pad and the bonding connection anchor points of the ground lead-out pad of the ASIC driver control chip are respectively bonded to the electrode point bonding connection anchor points and the ground pad bonding connection anchor points on the solid silicon wafer of the fixed comb structure layer to form the first gold-to-gold bonding layer. The steps for fabricating the fixed comb tooth structure layer are as follows: The substrate layer and silicon dioxide insulating layer of the solid silicon wafer of the fixed comb tooth structure layer are removed, leaving the device layer. Metal thin film deposition and photolithography patterning are performed on the front side of the device layer, retaining the grounding metal anchor points for connecting the moving comb teeth. Photolithography and silicon etching are performed on the front side of the device layer to create fixed comb tooth electrode grooves and form the fixed comb tooth body structure. Ground interconnect silicon pillars are fabricated to connect the grounding pads of the first gold-to-gold bonding layer and the second gold-to-gold bonding layer, forming a complete fixed comb tooth structure layer. The fixed comb tooth electrodes extend downwards along the electrode grooves to the first gold-to-gold bonding layer, and are connected to the ASIC driver control chip via the electrode point bonding anchor points. The second gold-to-gold bonding layer processing steps are as follows: a metal thin film deposition and patterning process is performed on a solid silicon wafer of the moving comb tooth structure layer to prepare grounding metal anchor points that are connected to the fixed comb teeth. The grounding metal anchor points of the moving comb teeth and the grounding metal anchor points of the fixed comb teeth are then bonded together to prepare the second gold-to-gold bonding layer. The steps for fabricating the moving comb tooth structure layer are as follows: remove the substrate layer and silicon dioxide insulating layer of the solid silicon wafer of the moving comb tooth structure layer, retain the device layer, perform photolithography and silicon etching on the device layer, fabricate the micromirror body, micromirror beam and moving comb teeth that match the fixed comb teeth, form the moving comb tooth structure layer, and complete the fabrication of the ASIC-MEMS micromirror integrated device.

2. The method according to claim 1, characterized in that, A wafer containing multiple ASIC-MEMS micromirror integrated devices is diced to obtain a single ASIC-MEMS micromirror integrated device.

3. The method according to claim 1, characterized in that, A ring-shaped metal bonding ring is fabricated around the periphery of the first gold-gold bonding layer to enhance the bonding strength at the bonding interface; and / or A ring-shaped metal bonding ring is prepared around the periphery of the second gold-gold bonding layer to enhance the bonding strength of the bonding interface.

4. The method according to claim 3, characterized in that, Annular metal bonding rings are fabricated around the periphery of the solid silicon wafers of the ASIC driver control chip and the fixed comb tooth structure layer, respectively. Gold-to-gold bonding is performed during the first gold-to-gold bonding layer treatment to fabricate the annular metal bonding rings of the first gold-to-gold bonding layer; and / or When preparing the fixed comb tooth structure layer, an annular metal bonding ring is prepared around the periphery of the fixed comb tooth structure layer. An annular metal bonding ring is prepared around the periphery of the solid silicon wafer of the moving comb tooth structure layer. During the second gold-gold bonding layer treatment, gold-gold bonding is performed to prepare the annular metal bonding ring of the second gold-gold bonding layer.

5. The method according to claim 1, 3, or 4, characterized in that, The gold-gold bonding control conditions for preparing the first gold-gold bonding layer and the second gold-gold bonding layer are as follows: temperature controlled at 200-250℃, less than or equal to 10℃. - A vacuum environment of 3Pa and pressure control between 7000mbar±500mbar ensure a void-free bonding interface, achieving a tight bond, while avoiding high-temperature damage to the ASIC driver control chip.

6. The method according to claim 1, characterized in that, The bonding metals used to prepare the first gold-gold bonding layer and the second gold-gold bonding layer are any of Au, Cu, Pt, and Ti / Au composite materials; the bonding process is any of hot-pressing bonding, low-temperature plasma activation bonding, and Au-Sn eutectic bonding.

7. The method according to claim 1, characterized in that, The driving form of the manufactured moving comb teeth is comb tooth drive, planar capacitor drive, or torsion beam drive.

8. The method according to claim 1, characterized in that, Contact through holes or shallow etched windows are opened at the bottom of the fixed comb teeth to reduce contact resistance.

9. The method according to claim 3 or 4, characterized in that, The annular metal bonding ring is constructed using a multi-layer metal stack.

10. The method according to claim 1, characterized in that: When preparing the fixed comb tooth structure layer, the overall fixed comb tooth structure is divided into four independent fixed comb tooth functional areas, which are used to drive the micro-mirror deflection angle in the corresponding direction.

Images