Membrane actuation structure and its manufacturing process

Abstract

The application provides a MEMS actuating structure and a preparation process thereof, and relates to the technical field of micro-electro-mechanical systems. The MEMS actuating structure comprises a fixed part, a moving part and decoupling beams. The fixed part and the moving part are arranged in an integrated structure, the fixed part is arranged at the periphery of the moving part, and a certain gap is formed between the fixed part and the moving part. The moving part comprises an array structure for providing driving force. The decoupling beams are arranged in the gap between the fixed part and the moving part. Each decoupling beam is provided with at least one corner. The decoupling beams are of a layered structure. The decoupling beams are provided with conductive lines. The conductive lines connect the fixed part and the moving part. The technical scheme framework is less and the structure is integrated. The overall structural strength is higher, and there is no need for late assembly. The conductive lines are arranged in the decoupling beams, so that physical collision between the lines is avoided, damage is reduced, and the service life is longer.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of micro-electro-mechanical system (MEMS), and in particular to a MEMS actuating structure and a preparation process thereof. BACKGROUND

[0002] With the development of science and technology, many electronic devices nowadays have the functions of taking photos or recording videos. The use of these electronic devices is becoming more and more common, and they are developing towards the direction of convenience and thinness, so as to provide users with more choices. Sensor-shift is an optical anti-shake technology for driving the imaging chip to make anti-shake motion relative to the lens. When external excitation / interference causes image blur, the position between the imaging chip and the optical lens of the camera can be adjusted to maintain the imaging field of view, so as to obtain a clear image. The anti-shake effect is better.

[0003] The MEMS actuating structure usually includes components such as micro-motors, electrodes, and sensors. These components can be manufactured by micro-nano processing technology and can be integrated on a micro-chip, so as to realize miniaturization and integration. The MEMS actuating structure has a wide range of applications in various fields, such as biomedical, optical, mechanical control, etc.

[0004] However, the existing MEMS actuating structure is a frame structure with an outer frame and an inner frame. The frame structure is relatively complex, and it is not easy to install. In addition, the existing MEMS actuator usually uses conductive lines to connect and conduct the fixed part and the moving part. Interference and physical collision between the conductive lines are prone to occur, which causes unstable actuating force and poor anti-shake effect. SUMMARY

[0005] The purpose of the embodiments of the present application is to provide a MEMS actuating structure and a preparation process thereof, so as to solve the problems of the existing technology, such as the frame structure being too complex, the comb teeth being too few, and the interference and physical collision between the conductive lines.

[0006] To solve the above technical problems, the embodiments of the present application provide the following technical solutions:

[0007] The first aspect of the present application provides a MEMS actuating structure, comprising: a fixed part, a moving part, and a decoupling beam; the fixed part is arranged outside the moving part, and there is a certain gap between the two; the moving part includes an array structure for providing driving force; the decoupling beam is arranged in the gap between the fixed part and the moving part, the decoupling beam is a layered structure, and the decoupling beam is provided with conductive lines, and the conductive lines conduct the fixed part and the moving part;

[0008] The fixed part, the moving part, and the decoupling beam are integrally formed, with one end of the decoupling beam connected to the fixed part and the other end connected to the moving part.

[0009] Preferably, in the aforementioned MEMS actuation structure, the gap between each layer of the decoupling beam is the same, and an insulating layer is provided inside the decoupling beam. The insulating layer partially wraps the conductive lines to achieve electrical insulation between the conductive lines. Both the conductive lines and the insulating layer abut against the upper surface of the decoupling beam.

[0010] Wherein, the length of the insulating layer and the conductive line along the Z-axis is less than the length of the decoupling beam along the Z-axis.

[0011] Preferably, in the aforementioned MEMS actuation structure, the fixing part includes an outer frame, the outer frame is provided with an anti-collision structure and a first decoupling beam connection end, the anti-collision structure is located on the inner side of the outer frame, and the first decoupling beam connection end is connected and conductive to the first end of the decoupling beam.

[0012] Preferably, in the aforementioned MEMS actuation structure, the moving part includes: an inner frame, a cross-shaped frame, an L-shaped frame, and an array structure; a space is formed inside the inner frame, the cross-shaped frame and the array structure are both disposed within the space, the array structure is composed of several arrays, the inner frame is connected to the cross-shaped frame, dividing the space into four subspaces, each of the four subspaces is provided with the array, an L-shaped frame is provided between the inner frame and the array, and the L-shaped frame is electrically connected to the decoupling beam and the array.

[0013] Preferably, in the aforementioned MEMS actuation structure, the inner frame includes two opposing first plates and two opposing second plates, the first plates and the second plates having a hollow structure to reduce the mass of the moving part; gaps are reserved at the four corners formed between the first plates and the second plates, the first plates are used to fix the imaging chip, the ends of the cross-shaped frame are connected to the first plates or the second plates, and the first plates and the second plates are electrically connected to the imaging chip.

[0014] Preferably, in the aforementioned MEMS actuation structure, the L-shaped frame includes a long side, a short side, and an L-shaped corner. The short side is disposed within the gaps reserved at the four corners of the first plate and the second plate. One end of the short side is provided with a second decoupling beam connection end, which is connected and conductive to the second end of the decoupling beam. The other end of the short side is connected to the long side, and the L-shaped corner is formed at the connection. The long side is adjacent to the first plate or the second plate and is electrically connected to the array.

[0015] Preferably, in the aforementioned MEMS actuation structure, each of the arrays includes a curved beam and several ridges. Each array contains two curved beams, one end of which is located at the L-shaped corner and the end of the long side away from the L-shaped corner, and the other end of which is located on the bridge of the cross-shaped frame. The several ridges include several ridges a and several ridges b. One end of ridge a is connected to the long side of the L-shaped frame, and the other end extends to the bridge of the cross-shaped frame with a gap between them. One end of ridge b is connected to the bridge of the cross-shaped frame, and the other end extends to the long side of the L-shaped frame with a gap between them. Ridges a and ridge b are respectively provided with comb teeth, and the comb teeth on ridge a and ridge b are staggered and intersecting each other. The comb teeth are conductive and form a capacitor to provide driving force.

[0016] The curved beam has a layered structure with equal gaps between each layer. Each curved beam contains conductive lines that connect the L-shaped frame and the cross-shaped frame.

[0017] Preferably, in the aforementioned MEMS actuation structure, the ridges a and b are arranged adjacent to each other, the ridges a and b extend in opposite directions, and the number of ridges a is N and the number of ridges b is N-1, or the number of ridges a is N-1 and the number of ridges b is N.

[0018] Preferably, in the aforementioned MEMS actuation structure, the comb tooth row includes comb tooth row a and comb tooth row b. Comb tooth row a is disposed on the ridge a and is kept energized or grounded; comb tooth row b is disposed on the ridge b and is kept grounded or energized; comb tooth row a includes comb teeth a and inter-tooth gap a, comb tooth row b includes comb teeth b and inter-tooth gap b, comb teeth a correspond to the inter-tooth gap b and each comb tooth a has a portion extending into the inter-tooth gap b, and comb teeth b correspond to the inter-tooth gap a and each comb tooth b has a portion extending into the inter-tooth gap a.

[0019] Preferably, in the aforementioned MEMS actuation structure, each of the decoupling beams has at least one corner, and the decoupling beams are V-shaped, N-shaped, or M-shaped structures.

[0020] A second aspect of this application provides a fabrication process for a MEMS actuation structure, the fabrication process comprising:

[0021] (1) Select an insulating silicon wafer; wherein the insulating silicon wafer includes a substrate layer, a structural layer and a buried layer;

[0022] (2) Deep reactive ion etching process, etching the first trench on the structural layer;

[0023] (3) Apply a first insulating layer to the exposed surface of the structural layer after etching the first trench in step (2);

[0024] (4) Fill the first trench in step (3) with conductive material and flatten the surface to complete the fabrication of all conductive lines;

[0025] (5) Etching a second trench on the structural layer;

[0026] (6) Fill the second groove with insulating material and apply a second insulating layer to the surface of the entire structural layer to complete the electrical insulation of the comb teeth from other structures;

[0027] (7) Etch away the second insulating layer;

[0028] (8) Apply a conductive layer to the surface of the structural layer in step (7);

[0029] (9) Etch away part of the deposited conductive layer to complete the connection between the comb teeth and the drive conductive circuit and the corresponding signal conductive circuit;

[0030] (10) A protective layer is deposited on the surface of step (9), and the surface is planarized;

[0031] (11) Flip the silicon insulator wafer processed in step (10) and process the base layer to etch away the patterned base layer;

[0032] (12) Etch away the part of the buried layer corresponding to the part of the substrate layer etched away in step (11) to complete the processing of the back side of the MEMS braking structure;

[0033] (13) Take another silicon wafer as a support wafer, etch away the silicon wafer corresponding to the pattern; coat the entire wafer with adhesive;

[0034] (14) Bond the insulating silicon wafer from step (11) to the support sheet from step (13);

[0035] (15) Etch away the protective layer material corresponding to the pattern;

[0036] (16) Etch away all the hollowed-out parts in the structure of step (16);

[0037] (17) Etch away the buried silicon dioxide layer so that the etched part is separated from the overall structure to form the MEMS actuation structure as described above.

[0038] Compared to the existing MEMS actuators with an external fixed frame, a middle moving frame, and a drive array, this actuation structure combines the middle moving frame and the drive array into a single moving part, which is integrated with the fixed part. This results in fewer frame components, higher overall structural strength, no need for post-assembly, easier installation, and a more robust structure. It also allows for the arrangement of more comb teeth, enabling the generation of greater driving force under the same voltage.

[0039] The decoupling beam in this structure adopts a layered structure, which facilitates the extraction of more sensor signal lines; at the same time, while keeping the soft elastic coefficient unchanged, the elastic coefficients in the hard and Z directions are increased several times, reducing unnecessary disturbances in the hard and Z directions.

[0040] The structure incorporates conductive lines within each layer of decoupling beams, enabling simultaneous connection and conduction between the fixed and moving parts. This eliminates the need for additional conductive lines, reduces mutual interference and physical collisions between lines, minimizes damage, extends service life, and enhances structural reliability. Attached Figure Description

[0041] The above and other objects, features, and advantages of exemplary embodiments of this application will become readily understood by reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of this application are illustrated by way of example and not limitation, with the same or corresponding reference numerals denoteing the same or corresponding parts, wherein:

[0042] Figure 1 A schematic diagram of the MEMS actuation structure in this invention is shown.

[0043] Figure 2 A schematic top view of the MEMS actuation structure in this invention is shown.

[0044] Figure 3 A schematic diagram of the fixing part in this invention is shown.

[0045] Figure 4 A schematic diagram of the structure of the moving part in this invention is shown.

[0046] Figure 5 A schematic diagram of the bent-bend beam connection in this invention is shown.

[0047] Figure 6 A schematic diagram of the array structure in this invention is shown.

[0048] Figure 7 A schematic diagram of the comb tooth row structure in this invention is shown.

[0049] Figure 8 A schematic diagram of the decoupling beam connection in this invention is shown.

[0050] Figure 9 A schematic diagram of the internal structure of the decoupling beam in this invention is shown.

[0051] Figure 10 An electrical schematic diagram of the first array in this invention is shown schematically;

[0052] Figure 11 An electrical schematic diagram of the second array in this invention is shown schematically;

[0053] Figure 12 An electrical schematic diagram of the third array in this invention is shown schematically;

[0054] Figure 13 An electrical schematic diagram of the fourth array in this invention is shown schematically;

[0055] Figure 14 A schematic diagram of the grounding of the MEMS actuation structure of the present invention is shown.

[0056] Figures 15 to 31 The fabrication process flow of the MEMS actuation structure of the present invention is illustrated schematically.

[0057] Explanation of icon numbers:

[0058] 1 is the fixed part, 11 is the outer frame, 111 is the anti-collision structure, 112 is the connection end of the first decoupling beam, and 113 is the clearance groove; 2 is the moving part, 21 is the inner frame, 211 is the first plate, 212 is the second plate, 22 is the cross-shaped frame, 221 is the bridge, 23 is the array structure, 23-1 is the first array, 23-2 is the second array, 23-3 is the third array, 23-4 is the fourth array, 231 is the curved beam, 232 is the ridge, 232a is ridge a, 232b is ridge b, 233 is the comb tooth row, 233a is comb tooth row a, 233a-1 is comb tooth a, 233a-2 is inter-tooth gap a, 233b is comb tooth row b, and 233b-1 is comb tooth b, 233b-2 is the inter-tooth gap b; 24 is the L-shaped frame, 241 is the long side, 242 is the short side, 2421 is the connection end of the second decoupling beam, 243 is the L-corner; 3 is the decoupling beam, 31 is the conductive line, 32 is the insulating layer, 33 is the corner, 34 is the gap between the decoupling beams; 4 is the insulator silicon wafer, 41 is the structural layer, 411 is the first trench, 412 is the first insulating layer, 413 is the conductive material, 414 is the second trench, 415 is the insulating material, 416 is the second insulating layer, 417 is the conductive layer, 418 is the protective layer, 42 is the buried layer, 43 is the base layer, 431 is the chamber, 432 is the separation trench; 5 is the support piece, 51 is the air groove. Implementation

[0059] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0060] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application pertains. Example

[0061] like Figure 1 , Figure 2 As shown, this embodiment provides a MEMS actuation structure, which is a microelectromechanical system actuation structure, including: a fixed part 1, a moving part 2, and a decoupling beam 3; the fixed part 1 is disposed around the moving part 2, with a certain gap between them and no direct contact point between them, the fixed part 1 and the moving part 2 are integrally structured, and play a role in limiting and fixing; the moving part 2 is provided with an array structure to provide driving force; the decoupling beam 3 is disposed in the gap between the fixed part 1 and the moving part 2, and is used to elastically connect the fixed part 1 and the moving part 2. The decoupling beam 3 is electrically connected to the fixed part 1 at one end and to the moving part 2 at the other end. The decoupling beam 3 has a layered structure, and the number of layers is determined according to the working conditions. The purpose is to increase the surface area of ​​the decoupling beam and better adjust the elastic coefficient (K value) of the decoupling beam. Each layer of the decoupling beam 3 is provided with a conductive line 31, which connects the fixed part 1 and the moving part 2. A certain gap is reserved between the decoupling beam 3 and the fixed part 1 and the moving part 2 to prevent friction, impact and other occurrences between the decoupling beam 3 and the moving part 2 and the fixed part 1 during the movement.

[0062] like Figure 9 As shown, in the specific implementation, the gaps between each layer of decoupling beams 3 (the gaps 34 between decoupling beams) are all the same. Each layer of decoupling beam 3 is provided with conductive lines 31 and an insulating layer 32. The insulating layer 32 partially wraps the conductive lines 31 to achieve electrical insulation between the conductive lines 31. Both the conductive lines 31 and the insulating layer 32 abut against the upper surface of the decoupling beam 3. The purpose of the conductive lines 31 is to provide a conductive connection between the imaging chip and the array structure 23, and the purpose of the insulating layer 32 is to prevent crosstalk between the conductive lines 31. The conductive lines 31 are metallic conductive lines. Figure 9 In the diagram, A represents the length of conductive line 31 along the Z-axis, and B represents the length of decoupling beam 3 along the Z-axis. <B。

[0063] like Figures 1 to 3As shown, in a specific implementation, the fixing part 1 includes an outer frame 11. The outer frame 11 is provided with an anti-collision structure 111 and a first decoupling beam connection end 112. The first decoupling beam connection end 112 electrically connects the fixing part 1 and the decoupling beam 3. The anti-collision structure 111 is located at the four inner corners of the outer frame 11, or it can be located at the inner edge of the four sides of the outer frame 11. It is used to reduce the impact of the collision between the moving part and the fixing part and to protect the moving part. The first decoupling beam connection end 112 is used to connect and conduct the fixing part 1 and the decoupling beam 3. The four inner sides of the outer frame 11 can also be provided with clearance grooves 113. Part of the decoupling beam 3 is located in the clearance grooves 113, and the first decoupling beam connection end 112 is located in the clearance grooves 113. The outer frame 11 can be of any shape, preferably a rectangular frame.

[0064] like Figure 1 , Figure 2 and Figure 4 As shown, in a specific implementation, the moving part 2 includes: an inner frame 21, a cross-shaped frame 22, an L-shaped frame 24, and an array structure 23; the inner frame 21 has a space inside, and the cross-shaped frame 22 and the array structure 23 are arranged in the space. The array structure 23 is divided into a first array 23-1, a second array 23-2, a third array 23-3, and a fourth array 23-4. The four arrays have the same structure, only the arrangement direction is different. The ridges 232 in the diagonal arrays are arranged in the same direction, and the ridges 232 in adjacent arrays along the X and Y axes are arranged in different directions. That is, the first array 23-1 and the third array 23-3 are arranged in the same direction, and the second array 23-2 and the fourth array 23-4 are arranged in the same direction. The inner frame 21 is connected to the cross-shaped frame 22, dividing the space into four subspaces. Each of the four subspaces is equipped with an array. The L-shaped frame 24 is located between the inner frame 21 and the arrays. The L-shaped frame 24 is electrically connected to the decoupling beam 3 and the arrays. The inner frame 21 can be an arbitrary shape of non-closed frame, preferably a rectangular non-closed frame.

[0065] like Figure 1 , Figure 2 , Figure 4As shown, in a specific implementation, the inner frame 21 includes two opposing first plates 211 and two opposing second plates 212. Both the first plates 211 and the second plates 212 have hollow structures to reduce the mass of the moving part 2. The first plates 211 and the second plates 212 can be a wide plate and a narrow plate, or they can be four plates without distinction between wide and narrow. The four corners formed between the first plates 211 and the second plates 212 are reserved with gaps, and a space is formed in the middle part. The first plate 211 is provided with a dispensing groove for fixing the glue and fixing the imaging chip. The first plates 211 and the second plates 212 are electrically connected to the imaging chip. The cross frame 22 is set in the space. The four sides of the cross frame 22 are four bridges 221. The ends of the cross frame 22 are integrally connected to the first plate 211 or the second plate 212, dividing the space into four sub-spaces.

[0066] like Figure 1 , Figure 4 As shown, in a specific implementation, the L-shaped frame 24 includes a long side 241, a short side 242, and an L-shaped corner 243. The short side 242 is located in the gaps reserved at the four corners of the first plate 211 and the second plate 212. The long side 241 is adjacent to the first plate 211 or the second plate 212 and has a small gap between it and the first plate 211 or the second plate 212. One end of the short side 242 is provided with a second decoupling beam connection end 2421, which is used to connect and conduct the moving part 2 and the decoupling beam 3. The second decoupling beam connection end 2421 electrically connects the L-shaped frame 24 and the decoupling beam 3. The other end of the short side 242 is connected to the long side 241 and forms an L-shaped corner 243 at the connection. The long side 241 is electrically connected to the array.

[0067] like Figures 4 to 6As shown, in a specific implementation, each array includes a bent beam 231 and several ridges 232. Each array contains two bent beams 231, positioned between the long side 241 and the bridge 221 of the cross-shaped frame 22. One end of each bent beam 231 is located at the L-corner 243, away from the long side 241. The other end of each bent beam 231 is positioned on the bridge 221 of the cross-shaped frame 11. The ridges 232 include several ridges a232a and several ridges b232b. One end of ridge a232a is connected to the long side 241 of the L-shaped frame 24, and the other end extends along the X or Y direction to the bridge 221 of the cross-shaped frame 22, leaving a gap between them. One end of ridge b232b is connected to the bridge of the cross-shaped frame 22. The other end extends along the X or Y direction to the long side 241 of the L-shaped frame 24, with a gap between it and the long side 241. Ridges a232a and b232b are respectively provided with comb teeth 233, and the comb teeth 233 on ridge a232a and the comb teeth 233 on ridge b232b are staggered and intersecting each other. The comb teeth 233 can conduct electricity and form a capacitor to provide driving force. The extension directions of two adjacent ridges 232 are different, and the number of ridges a232a is N and the number of ridges b232b is N-1. Alternatively, the number of ridges a232a can be N-1 and the number of ridges b232b can be N. A comb teeth 233 is provided between adjacent ridges a232a and ridge b232b. The comb teeth 233 are used for conducting electricity. The number of ridges a232a and b232b is selected according to the working conditions.

[0068] Among them, the bent beam 231 is a layered structure with a gap of the same distance between each layer. Each layer of the bent beam 231 is equipped with a conductive line 31, which connects the L-shaped frame 24 and the cross-shaped frame 22. The purpose of the bent beam 231 is to increase the surface area of ​​the decoupling beam 3, so as to better adjust the elastic coefficient (K value) of the decoupling beam 3.

[0069] like Figure 4 , Figure 6 , Figure 7 As shown, in a specific implementation, the comb tooth row 233 includes comb tooth row a233a and comb tooth row b233b. Comb tooth row a233a is disposed on ridge a232a extending from the long side 241 of the L-shaped frame 24 to the bridge 221 of the cross-shaped frame 22, and is kept energized with adjustable voltage. Comb tooth row b233b is disposed on ridge b242b extending from the bridge 221 of the cross-shaped frame 22 to the long side 241 of the L-shaped frame 24, and is kept grounded. When grounded, the electrical signal transmission is as follows: Figure 14As shown; the comb tooth row a233a includes comb teeth a233a-1 and inter-tooth gaps a233a-2, and the comb tooth row b233b includes comb teeth b233b-1 and inter-tooth gaps b233b-2. The comb teeth a233a-1 correspond to the inter-tooth gaps b233b-2, and a portion of each comb tooth a233a-1 extends into the inter-tooth gaps b233b-2. The comb teeth b233b-1 correspond to the inter-tooth gaps a233a-2, and a portion of each comb tooth b233b-1 extends into the inter-tooth gaps a233a-2.

[0070] like Figure 1 , Figure 8 As shown, in specific implementation, each decoupling beam 3 has at least one corner 33. The decoupling beam can be a V-shaped structure, an N-shaped structure, an M-shaped structure, or other structures, preferably an N-shaped structure.

[0071] In this invention, the number of decoupling beams 3, L-shaped frames 24, and arrays are all the same, all being four.

[0072] Working principle and working method of the present invention

[0073] The first type is linear displacement anti-jitter along the X and Y axes; the second type is rotational displacement anti-jitter with the Z axis as the pivot point, such as... Figures 1 to 14 As shown.

[0074] 1. Linear displacement anti-shaking along the X and Y axes: the X-axis movement is completed by the first and third arrays together, and the Y-axis movement is completed by the second and fourth arrays together.

[0075] (1) Moving to the left along the X-axis, the external electrical signal is transmitted to the L-shaped frame through the decoupling beam, and then transmitted to the spines a1, a2... aN respectively by the L-shaped frame. The spine a transmits the received electrical signal to the comb tooth row a on the right side of the spine a, so that the comb tooth row a on the right side of the spine a has a certain potential, which generates a certain attraction on the comb tooth row b corresponding to the comb tooth row a on the right side of the spine a, causing the moving part to move to the left along the X-axis, thereby realizing the image chip anti-shake. After the anti-shake is completed, the external electrical signal is disconnected, and the moving part can return to the initial position of the driver by relying on the reset force of the decoupling beam and the bending beam.

[0076] (2) Moving to the right along the X-axis, the external electrical signal is transmitted to the L-shaped frame through the decoupling beam, and then transmitted to the spines a1, a2... aN respectively by the L-shaped frame. The spine a transmits the received electrical signal to the comb tooth row a on the left side of the spine a, so that the comb tooth row a on the left side of the spine a has a certain potential, which generates a certain attraction on the comb tooth row b corresponding to the comb tooth row a on the left side of the spine a, causing the moving part to move to the right along the X-axis, thereby realizing the image chip anti-shake. After the anti-shake is completed, the external electrical signal is disconnected, and the moving part can return to the initial position of the driver by relying on the reset force of the decoupling beam and the bending beam.

[0077] (3) Moving upward along the Y-axis, the external electrical signal is transmitted to the L-shaped frame through the decoupling beam, and then transmitted to the spines a1, a2... aN respectively by the L-shaped frame. The spine a transmits the received electrical signal to the comb tooth row a below the spine a, so that the comb tooth row a below the spine a has a certain potential, which generates a certain attraction on the comb tooth row b corresponding to the comb tooth row a below the spine a, causing the moving part to generate an upward displacement along the Y-axis, thereby realizing image chip anti-shake. After the anti-shake is completed, the external electrical signal is disconnected, and the moving part can return to the initial position of the driver by relying on the reset force of the decoupling beam and the bending beam.

[0078] (4) Moving downward along the Y-axis, the external electrical signal is transmitted to the L-shaped frame through the decoupling beam, and then transmitted to the spines a1, a2... aN respectively by the L-shaped frame. The spine a transmits the received electrical signal to the comb tooth row a above the spine a, so that the comb tooth row a above the spine a has a certain potential, which generates a certain attraction on the comb tooth row b corresponding to the comb tooth row a above the spine a, causing the moving part to generate a downward displacement along the Y-axis, thereby realizing image chip anti-shake. After the anti-shake is completed, the external electrical signal is disconnected, and the moving part can return to the initial position of the driver by relying on the reset force of the decoupling beam and the bending beam.

[0079] 2. Rotational displacement anti-shake based on the Z-axis.

[0080] (1) An external electrical signal is supplied to the decoupling beam, causing the first array to move to the left along the X-axis, the second array to move downward along the Y-axis, the third array to move to the right along the X-axis, and the fourth array to move upward along the Y-axis. The four trends occur together in the same time period, which can complete the anti-shaking in the counterclockwise direction with the Z-axis as the rotation axis.

[0081] (2) An external electrical signal is supplied to the decoupling beam, causing the first array to move to the right along the X-axis, the second array to move upward along the Y-axis, the third array to move to the left along the X-axis, and the fourth array to move downward along the Y-axis. The four trends occur simultaneously within the same time period, thus completing the anti-shake in the clockwise direction with the Z-axis as the rotation axis. Example

[0082] like Figures 15 to 31 As shown in the figure, this embodiment 2 provides a fabrication process for a MEMS actuation structure. The MEMS actuation structure is a microelectromechanical system actuation structure, and the fabrication process includes:

[0083] (1) such as Figure 15 As shown, silicon insulator wafer 4 (SOI wafer) is selected; photoresist is spin-coated on SOI wafer 4, exposed by ultraviolet lithography machine, and etched to pattern it, which marks the position and shape of the etched trenches;

[0084] The insulating silicon wafer 4 includes a substrate layer 43, a buried layer 42 and a structural layer 41. The substrate layer 43 has a thickness of 5um to 50um, the structural layer 41 has a thickness of 50um to 400um, and the buried layer 42 has a thickness of 1um to 10um.

[0085] (1.1) Use mask No. 1, which includes pads, lines and glue tanks.

[0086] The circuitry includes sensor circuitry and comb drive circuitry. The circuitry is divided into wide lines and narrow lines. Narrow lines are on the beams, while wide lines are used in other non-beam areas. The width of the thinner conductors is the width of the narrow lines, ranging from 0.5µm to 3µm. The width of the pads and wider conductors is the width of the wide lines, which is approximately 3µm to 15µm, the width of the insulation layer. The width of the adhesive groove is 20µm to 200µm. The shape of the mask pads is square, and the side length of the square is the width of the wide lines.

[0087] (2) such as Figure 16 As shown, the first trench 411 is etched on the SOI wafer 4 processed in step (1) using a deep reactive ion etching (DIRE) process. The photoresist spin-coated during the processing of the SOI wafer 4 in step (1) is then removed (most positive photoresists can be developed using alkaline solvents such as KOH (potassium hydroxide), TMAH (tetramethylammonium hydroxide), acetone, or acetate).

[0088] The deepest part of the first trench 411 is the wide line area and the adhesive groove, reaching the depth of the entire structural layer 41. The etching time is controlled to be 20 minutes to 60 minutes to ensure that the etching stops immediately when the buried layer 42 (oxide layer) of the SOI wafer 4 is reached.

[0089] (3) such as Figure 17 As shown, a first insulating layer 412 is applied to the exposed surface of the structure layer 41 in the SOI wafer 4 after etching the first trench 411 in step (2).

[0090] The first insulating layer 412 can be a silicon dioxide insulating layer generated by thermal oxidation in a high-temperature furnace, or other insulating layer application processes.

[0091] (4) such as Figure 18 As shown, the first trench 411 in the SOI wafer 4 processed in step (3) is filled with conductive material 413. The first trench 411 is filled by a reliable deposition process to ensure that the first trench 411 is completely filled with conductive material 413 and the surface is planarized.

[0092] The conductive material 413 can be aluminum or other materials with high conductivity, high strength and low cost; the top boundary of the first trench 411 will be the position where the opening of the first trench 411 is flush with the substrate.

[0093] (5) such as Figure 19 As shown, the SOI wafer 4 processed in step (4) is spin-coated with photoresist, exposed by ultraviolet lithography, and etched into a pattern. Using the DIRE process, the second trench 414 is etched, and the trench depth of the second trench 414 reaches the entire structural layer depth. The photoresist spin-coated during the processing of SOI wafer 4 in step (5) is removed.

[0094] (5.1) Use mask No. 2, which includes an insulating layer.

[0095] The insulating layer has a wide linewidth, ranging from 3µm to 15µm. The etching time is controlled to ensure that the etching stops immediately when the insulating layer channel reaches the oxide layer 42 of the SOI wafer 4.

[0096] (6) For example Figure 20 As shown, the second trench 414 in the SOI wafer 4 processed in step (5) is filled with insulating material 415, which can be silicon nitride or oxide, and the surface is planarized. A second insulating layer 416 is left on the entire surface of the structural layer 41.

[0097] (7) For example Figure 21 As shown, the SOI wafer 4 processed in step (6) is spin-coated with photoresist, exposed with ultraviolet lithography, and etched to create a pattern. The second insulating layer 416 is etched away. The photoresist spin-coated during the processing of the SOI wafer 4 in step (7) is removed.

[0098] (7.1) Use mask No. 3. The parts to be removed include the exposed pads of the outer fixed frame and the inner moving frame, the end of the comb drive line and the comb area (to be bridged and energized in the back), the deep reactive etching part in the back (to form a structural layer), the hollowed-out weight reduction part, and the dispensing groove.

[0099] (8) such as Figure 22 As shown, a conductive layer 417 is deposited on the surface of the SOI wafer 4 processed in step (7). Its function is to form an electrical connection between the end of the comb drive line and the comb area, including high potential comb teeth and grounded comb teeth.

[0100] (9) For example Figure 23 As shown, the SOI wafer 4 processed in step (8) is spin-coated with photoresist, exposed by ultraviolet lithography, etched and patterned, and the part corresponding to the removal of mask 4 is etched away. The photoresist spin-coated during the processing of SOI wafer 4 in step (9) is removed.

[0101] (9.1) Use mask No. 4, which leaves exposed pads on the outer fixed frame and inner moving frame, the ends of the comb drive lines and the comb area connection lines, including high potential comb teeth and ground comb teeth.

[0102] (10) such as Figure 24As shown, a protective layer 418 is deposited on the surface of the SOI wafer 4 processed in step (9) and planarized. The material of the protective layer 418 is selected to be easy to etch and cannot be positive photoresist, silicon dioxide, or silicon, to prevent the previous layer and structure from being damaged in the subsequent process.

[0103] (11) such as Figure 25 As shown, the SOI wafer processed in step (10) is flipped over, and the substrate layer 43 is processed. The flipped SOI wafer 4 is spin-coated with photoresist, photolithographically etched, and patterned using an ultraviolet lithography machine. The silicon layer of the substrate layer 43 corresponding to the pattern is etched away. The photoresist spin-coated in step (11) of processing the SOI wafer 4 is removed.

[0104] (11.1) Use mask No. 5, which removes the chamber 431 and the separation groove 432.

[0105] (12) such as Figure 26 As shown, the silicon dioxide in the buried layer 42 of the SOI wafer 4 processed in step (11) is etched away.

[0106] (13) such as Figure 27 As shown, the SOI wafer processed in step (12) is spin-coated with photoresist, exposed with ultraviolet lithography, and etched to form a pattern. The silicon corresponding to the pattern is etched away. The photoresist spin-coated during the processing of SOI wafer 4 in step (13) is removed. The entire support sheet 5 is coated with photoresist.

[0107] (13.1) Take another silicon wafer as support sheet 5. The thickness of support sheet 5 is 300-1000um.

[0108] (13.2) Use mask No. 5, the part of which to be removed includes air groove 51, the width of which is 20um to 400um and the depth of which is 40um to 250um.

[0109] (13.3) Apply adhesive to the entire support sheet 5 for subsequent bonding. The adhesive thickness is 1µm to 10µm.

[0110] (14) such as Figure 28 As shown, the substrate layer 43 of the SOI wafer 4 processed in step (12) and the support sheet 5 processed in step (13) are bonded together.

[0111] (15) such as Figure 29 As shown, the wafer bonded in step (14) is spin-coated with photoresist, exposed with ultraviolet lithography, and etched to create a pattern. The protective layer material corresponding to the pattern is etched away. The photoresist spin-coated during wafer processing in step (15) is removed.

[0112] (15.1) Use mask No. 6, which only leaves the outer raised platform of the glue groove.

[0113] (16) such as Figure 30 As shown, the wafer processed in step (15) is spin-coated with photoresist, exposed using an ultraviolet lithography machine, and etched to create a pattern. DRIE etching is then used to remove the spin-coated photoresist from the wafer processing in step (16).

[0114] (16.1) Use mask #7 to remove all cutouts of the structure.

[0115] (16.2) Etch away the silicon material corresponding to the pattern of mask No. 7, and completely cut it out.

[0116] (16.3) Remove all adhesive between the support sheet 5 and the SOI wafer 4, and remove all adhesive from the upper surface of the SOI wafer 4.

[0117] (17) such as Figure 31 As shown, the silicon dioxide in the buried layer 42 of the wafer processed in step (16) is etched away, the structure is separated, and the MEMS actuation structure is obtained.

[0118] Specifically, the planarization process can be performed using a blanket etching process, or through IE, CMP, or a combination of both.

[0119] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A MEMS actuation structure, characterized in that, include: The device comprises a fixed part, a moving part, and a decoupling beam; the fixed part is disposed around the moving part, and there is a certain gap between them; the moving part includes an array structure for providing driving force; the decoupling beam is disposed in the gap between the fixed part and the moving part, the decoupling beam has a layered structure, and conductive lines are provided inside the decoupling beam, the conductive lines connecting the fixed part and the moving part; The gaps between each layer of the decoupling beams are the same. An insulating layer is also provided inside the decoupling beam. The insulating layer partially wraps the conductive lines to achieve electrical insulation between the conductive lines. Both the conductive lines and the insulating layer abut against the upper surface of the decoupling beam. The moving part includes: an inner frame, a cross-shaped frame, an L-shaped frame, and an array structure; the inner frame has a space inside, the cross-shaped frame and the array structure are both disposed in the space, the array structure is composed of several arrays, the inner frame is connected to the cross-shaped frame, dividing the space into four subspaces, each of the four subspaces is provided with the array, the inner frame and the arrays are provided with an L-shaped frame, and the L-shaped frame is electrically connected to the decoupling beam and the arrays; The fixed part, the moving part, and the decoupling beam are integrally formed. One end of the decoupling beam is connected to the fixed part, and the other end is connected to the moving part. The length of the insulating layer and the conductive line along the Z-axis is less than the length of the decoupling beam along the Z-axis.

2. The MEMS actuation structure as described in claim 1, characterized in that, The fixing part includes an outer frame, on which an anti-collision structure and a first decoupling beam connection end are provided. The anti-collision structure is located on the inner side of the outer frame, and the first decoupling beam connection end is connected and conductive to the first end of the decoupling beam.

3. The MEMS actuation structure as described in claim 1, characterized in that, The inner frame includes two opposing first plates and two opposing second plates. The first plates and the second plates have a hollow structure to reduce the mass of the moving parts. Gaps are reserved at the four corners formed between the first plates and the second plates. The first plates are used to fix the imaging chip. The ends of the cross-shaped frame are connected to the first plates or the second plates. The first plates and the second plates are electrically connected to the imaging chip.

4. The MEMS actuation structure as described in claim 3, characterized in that, The L-shaped frame includes a long side, a short side, and an L-shaped corner. The short side is located within the gaps reserved at the four corners of the first plate and the second plate. One end of the short side is provided with a second decoupling beam connection end, which is connected to and conducts through the second end of the decoupling beam. The other end of the short side is connected to the long side, forming the L-shaped corner at the connection. The long side is adjacent to the first plate or the second plate and is electrically connected to the array.

5. The MEMS actuation structure as described in claim 4, characterized in that, Each array includes a curved beam and several ridges. Each array contains two curved beams, one end of which is located at the L-shaped corner and the end of the long side away from the L-shaped corner. The other end of each curved beam is located on the bridge of the cross-shaped frame. The ridges include several ridges a and several ridges b. One end of ridge a is connected to the long side of the L-shaped frame, and the other end extends to the bridge of the cross-shaped frame with a gap between them. One end of ridge b is connected to the bridge of the cross-shaped frame, and the other end extends to the long side of the L-shaped frame with a gap between them. Ridges a and ridge b are each provided with comb teeth, and the comb teeth on ridge a and ridge b are staggered and intersecting each other. The comb teeth are conductive and form a capacitor to provide driving force. The curved beam has a layered structure with equal gaps between each layer. Each curved beam contains conductive lines that connect the L-shaped frame and the cross-shaped frame.

6. The MEMS actuation structure as described in claim 5, characterized in that, The ridges a and b are arranged adjacent to each other, and the ridges a and b extend in opposite directions. The number of ridges a is N and the number of ridges b is N-1, or the number of ridges a is N-1 and the number of ridges b is N.

7. The MEMS actuation structure as described in claim 5, characterized in that, The comb teeth row includes comb teeth row a and comb teeth row b. Comb teeth row a is disposed on the ridge a and is kept energized or grounded. Comb teeth row b is disposed on the ridge b and is kept grounded or energized. Comb teeth row a includes comb teeth a and inter-tooth gaps a. Comb teeth row b includes comb teeth b and inter-tooth gaps b. Comb teeth a correspond to inter-tooth gaps b, and a portion of each comb tooth a extends into the inter-tooth gap b. Comb teeth b correspond to inter-tooth gaps a, and a portion of each comb tooth b extends into the inter-tooth gap a.

8. The MEMS actuation structure as described in claim 1, characterized in that, Each of the decoupling beams has at least one corner, and the decoupling beams are V-shaped, N-shaped, or M-shaped structures.

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