Peripheral clamped micro actuator based on piezoelectric film and application of peripheral clamped micro actuator

Abstract

The invention relates to the technical field of micro electro mechanical systems, in particular to a peripheral clamped micro actuator based on a piezoelectric film and application thereof, and the peripheral clamped micro actuator comprises an outer frame which is used for supporting and protecting the micro actuator; the driving assembly comprises a piezoelectric film and electrode layers arranged above and below the piezoelectric film; the mass block is connected to the driving assembly; the peripheral fixing and supporting assembly is used for fixing and supporting a vibration system formed by the driving assembly and the mass block; wherein the driving assembly is connected with the outer frame through the peripheral fixing and supporting assembly, so that a peripheral fixing and supporting structure is realized; according to the miniature actuator, the size range of 0.1 mm to 10 mm can be achieved, and the requirement of extremely-miniature equipment is met; a single-sided film or double-sided film structure is adopted, and a simple cantilever beam or cantilever bridge design is combined, so that the manufacturing process is greatly simplified, and the cost is reduced; the stability and the accuracy of the actuator are ensured by the peripheral clamped structure, the vibration characteristic is optimized, and the durability and the environment adaptability of the actuator are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of micro-electromechanical systems (MEMS), and in particular to a peripherally clamped micro-actuator based on a piezoelectric film and applications thereof. Background Art

[0002] With the rapid development of microelectronics technology and the Internet of Things, miniaturized and intelligent devices are increasingly used in various fields. The demand for microactuators in these devices has also increased, especially in the fields of AR / VR devices, smart wearable devices, microfluidic systems, and precision instruments. Traditional electromagnetic actuators are difficult to meet the needs of these emerging applications due to their size and power consumption limitations. Therefore, the development of new microactuators has become a current research hotspot.

[0003] Piezoelectric actuators are ideal for micro actuators due to their fast response, low energy consumption, and high precision. However, existing piezoelectric actuators still have some problems:

[0004] 1. Too large: Although many existing piezoelectric actuators are smaller than electromagnetic actuators, they still cannot meet the needs of certain extremely miniaturized devices, such as smart contact lenses or micro medical robots.

[0005] 2. Complex structure: In order to improve performance, some micro piezoelectric actuators use complex multi-layer structures or special piezoelectric materials, which not only increases the manufacturing difficulty and cost, but also may reduce the reliability of the equipment.

[0006] 3. Insufficient fixed support: In the process of miniaturization, the fixed support of the actuator often becomes a key issue. Inappropriate support methods may lead to vibration loss, reduced positioning accuracy, and even damage to the equipment.

[0007] 4. Packaging difficulties: Micro piezoelectric actuators usually require special packaging to protect the fragile piezoelectric elements, which increases the complexity and cost of the device.

[0008] 5. Low integration: Many existing microactuators are difficult to effectively integrate with other microelectronic components, limiting their application in complex systems.

[0009] 6. Reliability issues: Under long-term use or in harsh environments, some microactuators may face problems such as fatigue, fracture or performance degradation.

[0010] The industry has been seeking new solutions to these problems. For example, some researchers have proposed micro piezoelectric actuators based on MEMS technology, but their manufacturing process is complex and the cost is high. Other scholars have tried to use new piezoelectric materials to improve performance, but these materials often have stability or mass production issues. Summary of the invention

[0011] The purpose of the present invention is to provide a peripherally clamped microactuator based on piezoelectric film which is simple in structure, small in size, reliable in performance and easy to integrate.

[0012] To achieve the above object, the present invention adopts the following technical solution: a peripherally clamped microactuator based on a piezoelectric film, comprising:

[0013] An outer frame, used for supporting and protecting the microactuator;

[0014] A driving component, comprising a piezoelectric film and electrode layers disposed above and below the piezoelectric film;

[0015] A mass block connected to the drive assembly; and

[0016] A peripheral fixing assembly, used for fixing and supporting the vibration system formed by the driving assembly and the mass block;

[0017] Wherein, the driving component is connected to the outer frame through the peripheral fixing component, thereby realizing the peripheral fixing structure.

[0018] Specifically, the driving assembly further comprises:

[0019] A cantilever beam structure attached to the electrode layer;

[0020] a layer of thin film material attached to the outside of the cantilever beam structure;

[0021] Wherein, the cantilever beam structure is one of the following: a single-sided piezoelectric cantilever beam, a double-sided piezoelectric cantilever beam or a cantilever bridge structure, and the thin film material layer and / or the piezoelectric material layer constitute a single-sided film structure or a double-sided film structure.

[0022] Specifically, the driving component is a single-sided membrane structure or a double-sided membrane structure;

[0023] When it is a single-sided membrane structure, it includes:

[0024] The piezoelectric film;

[0025] the electrode layer; and

[0026] A cantilever beam structure is attached below the electrode layer;

[0027] When it is a double-sided membrane structure, it includes:

[0028] An upper film, comprising the piezoelectric film and a first elastic film;

[0029] A lower film, which is a second elastic film; and

[0030] The mass block is arranged between the upper membrane and the lower membrane.

[0031] Specifically, the outer frame is a rectangular parallelepiped structure or a circular structure;

[0032] When the outer frame is a circular structure, the cantilever beams in the driving assembly are arranged in a rotationally symmetrical or mirror-symmetrical manner.

[0033] Specifically, the peripheral fixing component is made of one or more of the following materials: silicon, silicon dioxide, silicon nitride, aluminum, titanium, polyimide, stainless steel, polydimethylsiloxane, titanium dioxide, silicon carbide, quartz or ceramic material.

[0034] Specifically, the piezoelectric film is made of one or more of the following materials: lithium niobate, lead zirconium titanate or potassium sodium niobate.

[0035] Specifically, it also includes:

[0036] A packaging structure for protecting the piezoelectric film and the electrode layer and providing environmental isolation;

[0037] The packaging structure and the outer frame form a sealed cavity, and the driving component, the mass block and the peripheral fixing component are all arranged in the sealed cavity.

[0038] Specifically, when the cantilever beam structure is a single-sided piezoelectric cantilever beam, the mass block is fixed to the free end of the cantilever beam;

[0039] When the cantilever beam structure is a bilateral piezoelectric cantilever beam, the mass block is fixed at the middle position of two parallel cantilever beams;

[0040] When the cantilever beam structure is a cantilever bridge structure, the mass block is fixed at the center position of the cantilever bridge.

[0041] Specifically, the size of the microactuator is between 0.1 mm and 10 mm, and can generate a displacement of 0.1-10 μm within a frequency range of 1-100 Hz.

[0042] The microactuator is used in the following equipment:

[0043] Tactile feedback devices for AR / VR glasses; tactile output devices for smart rings; precise liquid control devices for microfluidic systems; micro-manipulation tools in the biomedical field; or fine-tuning mechanisms for precision instruments.

[0044] The present invention solves these problems ingeniously by adopting a peripheral clamping structure based on a piezoelectric film.

[0045] Its main beneficial effects include:

[0046] 1. Achieving a smaller size: The microactuator of the present invention can be sized in the range of 0.1 mm to 10 mm, meeting the needs of extremely miniaturized equipment.

[0047] 2. Simplified structural design: The use of single-sided membrane or double-sided membrane structure, combined with a simple cantilever beam or cantilever bridge design, greatly simplifies the manufacturing process and reduces costs.

[0048] 3. Provides effective fixed support: The peripheral fixed support structure ensures the stability and accuracy of the actuator and optimizes the vibration characteristics.

[0049] 4. Improved environmental adaptability: Through reasonable material selection and packaging design, the durability and environmental adaptability of the actuator are enhanced.

[0050] 5. Enhanced integration capability: The design of the present invention is easily compatible with existing microelectronic manufacturing processes and improves integration with other components.

[0051] 6. Achieved diversified movement modes: Through different structural designs, unidirectional, bidirectional and even complex three-dimensional movement can be achieved to meet various application requirements.

[0052] 7. Improved energy efficiency: A displacement of 0.1-10μm can be generated within a frequency range of 1-100Hz, demonstrating excellent low power consumption characteristics.

[0053] In summary, the peripherally clamped microactuator based on piezoelectric film provided by the present invention provides a new and efficient solution for the development of miniaturized devices, and is expected to play an important role in multiple fields such as AR / VR, wearable devices, microfluidic systems, and precision instruments. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a front view of the rectangular single-sided membrane single-sided piezoelectric cantilever arm peripherally fixed microactuator in Example 1 of the present invention.

[0055] Figure 2 This is a three-dimensional plan view of the rectangular single-sided membrane single cantilever arm peripherally fixed micro-actuator in Example 1 of the present invention.

[0056] Figure 3 This is a front view of the microactuator of Example 2 of the present invention, in which the microactuator has a single-sided membrane and double-sided piezoelectric cantilever arm and is fixed around the periphery.

[0057] Figure 4 This is a three-dimensional plan view of the microactuator of the microactuator with single-sided membrane and double-sided piezoelectric cantilever arms fixed around the periphery according to Example 2 of the present invention.

[0058] Figure 5Schematic diagram of the structure of the micro-actuator with a single-sided membrane cantilever bridge fixed around the periphery in Example 3 of the present invention.

[0059] Figure 6 This is a three-dimensional plan view of a microactuator with peripheral clamping of a single-sided membrane cantilever bridge according to Example 3 of the present invention.

[0060] Figure 7 This is a front view of a rotationally symmetrical microactuator with a circular single-sided membrane periphery fixed cantilever beam according to Example 4 of the present invention.

[0061] Figure 8 This is a three-dimensional front view of a rotationally symmetrical microactuator with a circular single-sided membrane periphery fixed cantilever beam according to Example 4 of the present invention.

[0062] Fig. 9 1. A top view of a rotationally symmetrical microactuator with a circular single-sided membrane periphery fixed cantilever beam according to Example 4 of the present invention.

[0063] Fig.10 This is a front view of a microactuator with a double-sided membrane and a single-sided piezoelectric cantilever arm with peripheral fixation according to Example 5 of the present invention.

[0064] Fig.11 This is a three-dimensional plan view of the micro-actuator with a double-sided membrane and a single-sided piezoelectric cantilever arm fixed around the periphery according to Example 5 of the present invention.

[0065] Fig.12 Schematic diagram of the structure of the micro-actuator with the periphery of the double-sided membrane cantilever bridge fixed according to Example 6 of the present invention.

[0066] Fig.13 This is a three-dimensional plan view of the micro-actuator with peripheral clamping of the double-sided membrane cantilever bridge according to Example 6 of the present invention.

[0067] Fig.14 This is a front view of the micro-actuator-1 with double-sided membrane and double cantilever beam arms fixed around the periphery according to Example 7 of the present invention.

[0068] Fig.15 This is a three-dimensional front view of the micro-actuator-1 with double-sided membrane and double cantilever beam arms fixed around the periphery according to Example 7 of the present invention.

[0069] Fig.16 This is a front view of the micro-actuator-2 with double-sided membrane and double cantilever arm peripherally fixed according to Example 7 of the present invention.

[0070] Fig.17 This is a three-dimensional front view of the micro-actuator-2 with double-sided membrane and double cantilever beam arms fixed around the periphery according to Example 7 of the present invention.

[0071] Fig.18 This is a schematic structural diagram of the rotationally symmetrical microactuator-1 with a cantilever beam fixed around a circular double-sided membrane according to Example 8 of the present invention.

[0072] Fig.19 This is a three-dimensional front view of the rotationally symmetrical microactuator-1 with a cantilever beam fixed around a circular double-sided membrane according to Example 8 of the present invention.

[0073] Fig. 20 This is a schematic structural diagram of the rotationally symmetrical microactuator-2 with a cantilever beam fixed around a circular double-sided membrane according to Example 8 of the present invention.

[0074] Fig.21 It is a three-dimensional front view of the rotationally symmetrical microactuator 2 with a cantilever beam fixed around a circular double-sided membrane according to Example 8 of the present invention. DETAILED DESCRIPTION

[0075] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0076] Specific implementation method The present invention provides a peripheral clamped microactuator based on piezoelectric film and its application and preparation method. The microactuator adopts piezoelectric film technology and combines the peripheral clamped structure to achieve high-precision and small-size actuation effect, and is particularly suitable for AR / VR devices, smart wearable devices and other fields that require miniaturized tactile feedback.

[0077] First, the microactuator of the present invention comprises an outer frame 1, a driving assembly 2, a mass block 3 and a peripheral fixed support assembly 4. The outer frame 1 is used to support and protect the entire actuator structure, and can be designed in a rectangular or circular shape. The driving assembly 2 is the core part of the actuator, and comprises a piezoelectric film 21 and an electrode layer 22 arranged above and below the piezoelectric film 21. The mass block 3 is connected to the driving assembly 2 to enhance the vibration effect. The peripheral fixed support assembly 4 fixes and supports the vibration system formed by the driving assembly 2 and the mass block 3, and connects it to the outer frame 1, thereby realizing the peripheral fixed support structure.

[0078] Preferably, in one embodiment of the present invention, the driving component 2 also includes a cantilever beam structure 23. The cantilever beam structure 23 is attached to the electrode layer 22, and can adopt a single-sided piezoelectric cantilever beam, a double-sided piezoelectric cantilever beam or a cantilever bridge structure. This design increases the flexibility and precision of the actuator. For example, in the application of AR glasses, a single-sided piezoelectric cantilever beam structure can provide precise unidirectional tactile feedback, while a double-sided piezoelectric cantilever beam structure can achieve a more complex vibration mode and enhance the user's sense of immersion; it also includes a thin film material layer 24 attached to the outside of the cantilever beam structure; the thin film material layer 24 and / or the piezoelectric material layer constitute a single-sided membrane structure or a double-sided membrane structure.

[0079] In order to adapt to different application requirements, the driving component 2 of the present invention can adopt a single-sided membrane structure or a double-sided membrane structure. The single-sided membrane structure includes a piezoelectric film 21, an electrode layer 22, and a cantilever beam structure 23 attached to the bottom of the electrode layer 22. This structure is simple and easy to manufacture, and is particularly suitable for cost-sensitive application scenarios, such as mass-produced smart bracelets. The double-sided membrane structure includes an upper membrane (including a piezoelectric film 21 and a first elastic film), a lower membrane (which is a second elastic film), and a mass block 3 arranged between the upper membrane and the lower membrane. The double-sided membrane structure provides better mechanical stability and vibration characteristics, and is suitable for scenarios requiring high reliability, such as micro-manipulation tools in medical equipment.

[0080] In view of the diversity of application environments, the outer frame 1 of the present invention can adopt a rectangular parallelepiped structure or a circular structure. In particular, when the outer frame 1 is a circular structure, the cantilever beams in the driving assembly 2 are arranged in rotational symmetry or mirror symmetry. This design performs well in circular devices such as smart rings and can provide all-round tactile feedback.

[0081] In order to ensure the performance and reliability of the microactuator, the material selection of the peripheral fixed support component 4 is crucial. The material used in the present invention can be one or more of silicon, silicon dioxide, silicon nitride, aluminum, titanium, polyimide, stainless steel, polydimethylsiloxane, titanium dioxide, silicon carbide, quartz or ceramic materials. These materials have good mechanical properties and thermal stability, and can provide stable support at a micro scale. For example, in the application of microfluidic systems, the peripheral fixed support component 4 made of silicon material can be compatible with existing MEMS processes, which is convenient for system integration.

[0082] The piezoelectric film 21 is the core component of the present invention, and the material selection directly affects the performance of the actuator. The piezoelectric material used in the present invention can be one or more of lithium niobate, lead zirconium titanate or potassium sodium niobate. These materials have excellent piezoelectric properties and can achieve high-precision displacement control at low voltage. In the fine-tuning mechanism of precision instruments, the piezoelectric film 21 made of lead zirconium titanate can provide nanometer-level precision adjustment capabilities.

[0083] In order to protect the microactuator from environmental influences, the present invention further includes a packaging structure 5. The packaging structure 5 and the outer frame 1 form a sealed cavity, and the drive component 2, the mass block 3 and the peripheral fixed support component 4 are all arranged in the sealed cavity. This design not only protects the piezoelectric film 21 and the electrode layer 22, but also provides good environmental isolation to ensure the stable operation of the actuator in various complex environments. For example, in biomedical applications, the packaging structure 5 can prevent the biological fluid from corroding the actuator.

[0084] The position of the mass block 3 of the microactuator of the present invention is different under different cantilever beam structures. When the cantilever beam structure 23 is a single-sided piezoelectric cantilever beam, the mass block 3 is fixed at the free end of the cantilever beam. This design can maximize the vibration amplitude and is suitable for applications that require strong tactile feedback. When it is a double-sided piezoelectric cantilever beam, the mass block 3 is fixed in the middle position of the two parallel cantilever beams, providing a more balanced vibration characteristic. In the cantilever bridge structure, the mass block 3 is fixed in the center position of the cantilever bridge, which can achieve complex vibration modes.

[0085] Based on the design of the present invention, the size of the microactuator can be controlled between 0.1mm and 10mm, and can produce a displacement of 0.1-10μm in the frequency range of 1-100Hz. This tiny size and precise displacement control make the present invention particularly suitable for application scenarios such as tactile feedback devices for AR / VR glasses, tactile output devices for smart rings, precise liquid control devices for microfluidic systems, micro-manipulation tools in the biomedical field, and fine-tuning mechanisms for precision instruments.

[0086] The preparation method of the present invention comprises the following steps: first, a piezoelectric film 21 is deposited on a substrate, which can be done by sputtering or sol-gel method. Then, an electrode layer 22 is deposited on the upper and lower surfaces of the piezoelectric film 21, usually by metal evaporation or electroplating technology. Next, a cantilever beam structure 23 is formed by micromachining technology (such as photolithography and etching). After that, a mass block 3 is fixed at the end of the cantilever beam, and micro-welding or bonding technology can be used. Finally, a peripheral fixture component 4 is used to fix and support the entire structure, and then encapsulate it.

[0087] In summary, the peripherally clamped microactuator based on piezoelectric film provided by the present invention has the advantages of simple structure, small size, high precision, good reliability, etc. Through flexible selection of materials and structural design, it can meet the needs of various application scenarios and provide a new solution for tactile feedback and precision control of miniaturized devices.

[0088] Next, we will describe the microactuator of the present invention in more detail with reference to specific embodiments.

[0089] Example 1: Rectangular single-sided membrane single-sided piezoelectric cantilever arm peripheral clamped microactuator

[0090] like Figure 1-2As shown, the rectangular single-sided membrane single-sided piezoelectric cantilever arm peripheral fixed support microactuator includes an outer frame 1, a driving component 2, a mass block 3 and a peripheral fixed support component 4. The driving component 2 includes a piezoelectric film 21, an electrode layer 22 and a single-sided piezoelectric cantilever beam 23. In this embodiment, the microactuator adopts a rectangular outer frame 1, and its size is 5mm×3mm×1mm. The driving component 2 adopts a single-sided membrane structure, including a piezoelectric film 21, an electrode layer 22 and a single-sided piezoelectric cantilever beam 23. The piezoelectric film 21 is made of lead zirconium titanate (PZT) material with a thickness of 2μm. The electrode layer 22 is made of gold material with a thickness of 100nm. The single-sided piezoelectric cantilever beam 23 is 3mm long, 0.5mm wide, 10μm thick, and made of silicon material. The mass block 3 is in the shape of a cube with a side length of 0.5mm, and is made of tungsten material to increase the mass. The peripheral fixed support component 4 is made of silicon material with a thickness of 0.5mm.

[0091] Preferably, in one embodiment of the present invention, the operating voltage range of the piezoelectric film 21 is 0-5V, within which the free end of the cantilever beam 23 can produce a displacement of 0-5μm. This design is particularly suitable for tactile feedback of the temples of AR glasses because it can provide sufficient tactile stimulation in a limited space while maintaining low power consumption.

[0092] In order to improve the reliability of the actuator, the packaging structure 5 uses epoxy resin material to seal the entire actuator in a protective layer with a thickness of 0.2 mm. This packaging not only protects the fragile piezoelectric film 21 and electrode layer 22, but also improves the impact resistance of the entire device.

[0093] Example 2: Microactuator with single-sided membrane and bilateral piezoelectric cantilever arms with peripheral clamping

[0094] like Figure 3 and Figure 4 As shown, the micro-actuator with a single-sided membrane and bilateral piezoelectric cantilever arm fixed around the periphery adopts two parallel cantilever beams 23, and the mass block 3 is located in the middle of the two cantilever beams. Figure 2 Shows the main view, Figure 3 A 3D plan view is shown, clearly showing the double cantilever structure.

[0095] Based on the design of Example 1, this embodiment changes the single-sided cantilever beam into a double-sided cantilever beam structure. The two parallel cantilever beams 23 are each 2.5 mm long, 0.4 mm wide, 8 μm thick, and made of silicon. The mass block 3 is located in the middle of the two cantilever beams and has a size of 0.8 mm×0.4 mm×0.4 mm.

[0096] Due to the use of a bilateral cantilever beam design, this structure has better stability and symmetry. Therefore, under the same driving voltage, the actuator of this embodiment can produce more precise and consistent vibrations. For example, under a driving voltage of 2.5V, the displacement of the mass 3 can be accurately controlled within the range of 2.5±0.1μm. This high-precision control makes the actuator particularly suitable for smart ring devices that require precise tactile feedback.

[0097] Example 3: Microactuator with peripheral clamping of single-sided membrane cantilever bridge

[0098] like Figure 4 , Figure 5 and Figure 6 As shown, the microactuator with a single-sided membrane cantilever bridge and peripheral clamping adopts a cantilever bridge structure. Figure 4 As a main view, the overall layout of the cantilever bridge 23 is shown. Figure 5 It is a three-dimensional plan view, showing the connection relationship between the cantilever bridge 23 and the mass block 3.

[0099] This embodiment adopts a cantilever bridge structure, the outer frame 1 is circular, with a diameter of 6mm and a height of 1.2mm. The cantilever bridge 23 has a length of 4mm, a width of 0.6mm and a thickness of 12μm. The mass block 3 is located at the center of the cantilever bridge, is cylindrical, has a diameter of 0.8mm and a height of 0.5mm.

[0100] Preferably, in one embodiment of the present invention, the cantilever bridge structure 23 is designed with a composite material, including a 10 μm thick silicon substrate and a 2 μm thick aluminum nitride piezoelectric layer. This composite structure improves the stiffness of the cantilever bridge while maintaining good piezoelectric properties. Within the driving voltage range of 0-10V, the mass block 3 can generate a vertical displacement of 0-8 μm.

[0101] This design is particularly suitable for precise liquid control in microfluidic systems. Because the cantilever bridge structure provides stable vertical motion, it can accurately control the dispensing of trace amounts of liquid. For example, at a 5V driving voltage, the actuator can accurately control the dispensing volume of 5nL of liquid with an error of no more than 0.1nL.

[0102] Example 4: A microactuator with a rotationally symmetric cantilever beam fixed around a circular single-sided membrane

[0103] like Figure 7 , Figure 8 and Fig. 9 As shown, the rotationally symmetric microactuator with a circular single-sided membrane periphery-fixed cantilever beam adopts a circular design. Figure 7 For the main view, Figure 8 The 3D front view shows the rotationally symmetric cantilever beam layout. Fig. 9 It is a top view, which clearly shows the rotationally symmetrical arrangement of the cantilever beams 23 .

[0104] This embodiment adopts a circular design, the outer frame 1 has a diameter of 8 mm and a height of 1.5 mm. The driving assembly 2 includes four cantilever beams 23 arranged in a cross shape, each cantilever beam is 2 mm long, 0.3 mm wide and 7 μm thick. The mass block 3 is located at the center of the cross and is spherical with a diameter of 0.6 mm.

[0105] In order to achieve a rotationally symmetrical design, the four cantilever beams 23 are made of exactly the same material and size. The piezoelectric film 21 is made of lithium niobate material with a thickness of 1.5 μm. The electrode layer 22 is made of platinum material with a thickness of 80 nm. This symmetrical design ensures that the actuator has consistent performance in all directions.

[0106] Preferably, in one embodiment of the present invention, the four cantilever beams 23 can be independently controlled to achieve complex vibration modes. For example, by applying drive signals of different phases to the four cantilever beams, rotational tactile feedback can be generated. In the frequency range of 20-100 Hz, the mass block 3 can generate a displacement amplitude of 2-10 μm. This multi-degree-of-freedom control makes the actuator particularly suitable for the tactile feedback system of the VR handle, which can simulate various complex touches.

[0107] Example 5: Microactuator with double-sided membrane and single-sided piezoelectric cantilever arm and peripheral clamping

[0108] like Fig.10 and Fig.11 As shown, the microactuator with double-sided membrane and single-sided piezoelectric cantilever arm fixed around the periphery includes an upper membrane 24 and a lower membrane 26 . Fig.10 For the main view, Fig.11 It is a three-dimensional plan view, showing how the mass block 3 is sandwiched between the upper membrane 24 and the lower membrane 26.

[0109] This embodiment adopts a double-sided film structure, and the outer frame 1 is a rectangular parallelepiped with a size of 6mm×4mm×1.5mm. The upper film 24 includes a 2μm thick PZT piezoelectric film 21 and a 5μm thick polyimide first elastic film 25. The lower film 26 is an 8μm thick polyimide second elastic film. The mass block 3 is sandwiched between the upper film 24 and the lower film 26, with a size of 1mm×0.8mm×0.3mm.

[0110] Preferably, in one embodiment of the present invention, the upper membrane 24 and the lower membrane 26 are made of polyimide materials of different thicknesses. This asymmetric design can produce complex vibration modes. For example, when a 3V driving voltage is applied to the upper membrane 24, the mass block 3 not only produces vertical displacement, but also produces a slight tilting motion. This composite motion can produce a richer touch in the tactile feedback system of the smart watch.

[0111] Example 6: Microactuator with double-sided membrane cantilever bridge and fixed support

[0112] like Fig.12 and Fig.13 As shown, the micro-actuator with the periphery of the double-sided membrane cantilever bridge fixedly supported adopts an elliptical outer frame 1. Fig.12 For the main view, Fig.13 It is a three-dimensional plan view showing the "sandwich" structure of the upper membrane 24 and the lower membrane 26, and how the cantilever bridge 23 is fixed to the two ends of the outer frame 1 through the peripheral fixing components 4.

[0113] This embodiment adopts a double-sided film cantilever bridge structure, and the outer frame 1 is elliptical, with a major axis of 7mm, a minor axis of 5mm, and a height of 1.8mm. The upper film 24 and the lower film 26 both adopt a "sandwich" structure, including a 1.5μm thick potassium sodium niobate piezoelectric film 21, sandwiched between two layers of 100nm thick gold electrode layers 22, and the outer layer is a 6μm thick polydimethylsiloxane (PDMS) elastic film 25. The cantilever bridge 23 is 4.5mm long and 0.7mm wide, and is fixed to the two ends of the outer frame 1 through the peripheral fixing component 4.

[0114] The mass block 3 is located at the center of the cantilever bridge 23, and is made of titanium alloy, and is in the shape of a flat cylinder, with a diameter of 1.2 mm and a height of 0.4 mm. Preferably, in one embodiment of the present invention, the surface of the mass block 3 is specially treated to have a micron-level roughness, and this design can increase the friction between the mass block 3 and the upper and lower membranes, and improve the stability of the overall structure.

[0115] Due to the double-sided membrane design, the actuator has excellent bidirectional driving capability. When a positive voltage is applied to the upper membrane 24 and a negative voltage is applied to the lower membrane 26, the mass block 3 moves upward; otherwise, it moves downward. Within the driving voltage range of ±5V, the mass block 3 can achieve a vertical displacement of ±7μm. This bidirectional driving characteristic makes the actuator particularly suitable for micro-robot joint control that requires precise force feedback. For example, in the end effector of a minimally invasive surgical robot, the actuator can provide precise tactile feedback to help doctors perceive the soft tissue characteristics of the surgical site.

[0116] Example 7: Microactuator with double-sided membrane and double cantilever arm with peripheral fixation

[0117] like Fig.14 , Fig.15 , Fig.16 and Fig.17 As shown, there are two variations of the double-sided membrane dual cantilever arm perimeter-fixed microactuator. Fig.14 and Fig.15 The first variant is shown in the front and 3D views. Fig.16 and Fig.17 The front and 3D front views of the second variant are shown, clearly showing the double cantilever beam structure and double-sided membrane design.

[0118] This embodiment adopts a double-sided film double cantilever arm structure, and the outer frame 1 is square, with a side length of 6mm and a height of 2mm. The upper film 24 and the lower film 26 have the same structure, both including a 2μm thick lead zirconium titanate (PZT) piezoelectric film 21, an 80nm thick platinum electrode layer 22 on the upper and lower sides, and an 8μm thick polyimide elastic film 25 on the outermost layer. The two parallel cantilever beams 23 are 3.5mm long, 0.5mm wide, and 1.5mm apart.

[0119] The mass block 3 is located at the center between the two suspension beams 23, is made of tungsten alloy, is in the shape of a cuboid, and has a size of 1.5 mm×1 mm×0.6 mm. Preferably, in one embodiment of the present invention, a tiny cavity is provided inside the mass block 3, which can be filled with materials of different densities according to different application requirements, thereby adjusting the natural frequency of the actuator.

[0120] This double-sided membrane and double cantilever beam structure provides extremely high flexibility and stability. By independently controlling the upper and lower membranes and the two cantilever beams, complex three-dimensional motion can be achieved. For example, in the frequency range of 10-200Hz, the actuator can produce a displacement of 2-8μm in the XY plane and a displacement of 1-5μm in the Z axis. This multi-degree-of-freedom motion is particularly suitable for lens focusing mechanisms in high-precision optical systems. In the automatic focusing system of an astronomical telescope, the actuator can simultaneously achieve translation and tilt adjustment of the lens, greatly improving the imaging quality.

[0121] Example 8: A microactuator with a rotationally symmetric cantilever beam fixed around a circular double-sided membrane

[0122] like Fig.18 , Fig.19 , Fig. 20 and Fig.21 As shown, the micro-actuator with a circular double-sided membrane and a cantilever beam fixed around the periphery and rotationally symmetric uses a cantilever beam 23 arranged in a hexagonal star shape. Fig.18 For the main view, Fig.19 This is a three-dimensional main view, showing the complex rotationally symmetrical structure and the position of mass block 3 at the center of the star-shaped structure. Fig. 20 and Fig.21 Another variant is the main view and the 3D main view.

[0123] This embodiment adopts a circular double-sided membrane structure, and the outer frame 1 is a cylinder with a diameter of 9 mm and a height of 2.2 mm. The upper membrane 24 and the lower membrane 26 both adopt a composite structure, including a 1.8 μm thick lithium niobate piezoelectric film 21, a 90 nm thick gold electrode layer 22, and a 7 μm thick silicon nitride elastic film 25. The cantilever beams 23 are arranged in a hexagonal star shape, with a total of 6, each 2.5 mm long and 0.4 mm wide.

[0124] The mass block 3 is located at the center of the star-shaped structure, and is made of nickel-iron alloy material, in the shape of a hexagonal prism, with a diameter of 1.5 mm and a height of 0.8 mm. Preferably, in one embodiment of the present invention, each of the six sides of the mass block 3 is attached with a micro permanent magnet, which can realize additional electromagnetic drive in cooperation with an external coil, thereby enhancing the output force of the actuator.

[0125] This rotationally symmetric design not only provides excellent all-round control capabilities, but also has extremely high structural stability. Complex spatial motion can be achieved by precisely controlling the driving voltage and phase of the six cantilever beams. For example, in the frequency range of 0-300Hz, the actuator can produce a radial displacement of 0-15μm in the plane, a rotation angle of 0-30°, and a displacement of 0-10μm in the vertical direction. This all-round control feature makes the actuator very suitable for use in miniature optical scanning systems. In portable spectrometers, the actuator can drive micro-mirrors to achieve fast and accurate two-dimensional scanning, greatly improving the efficiency and accuracy of spectral acquisition.

[0126] Through the above 8 embodiments, we have described in detail various implementations of the peripheral clamped microactuator based on piezoelectric film of the present invention. These embodiments cover single-sided membrane and double-sided membrane structures, single cantilever, double cantilever and cantilever bridge structures, as well as various shapes and material combinations. Each design is optimized for a specific application scenario, demonstrating the flexibility and wide applicability of the present invention.

[0127] The common feature of these micro actuators is that they use piezoelectric film as the core driving element, combined with a peripheral fixed support structure to achieve a stable and reliable miniaturized design. Through the carefully designed structure and material combination, these actuators can achieve precise displacement control in a very small size, with a wide frequency response range, low energy consumption and high reliability.

[0128] The microactuator of the present invention can be widely used in AR / VR devices, smart wearable devices, microfluidic systems, biomedical devices, precision optical systems and other fields, providing new solutions for these rapidly developing technical fields. With the continuous progress of microelectronics technology and materials science, the microactuator of the present invention has room for further optimization and development, and is expected to play an important role in more emerging fields.

[0129] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A peripherally clamped microactuator based on a piezoelectric film, characterized in that: include: An outer frame, used for supporting and protecting the microactuator; A driving component, comprising a piezoelectric film and electrode layers disposed above and below the piezoelectric film; A mass block connected to the driving assembly; as well as A peripheral fixing assembly, used for fixing and supporting the vibration system formed by the driving assembly and the mass block; Wherein, the driving component is connected to the outer frame through the peripheral fixing component, thereby realizing the peripheral fixing structure.

2. The microactuator according to claim 1, characterized in that: The drive assembly further comprises: A cantilever beam structure attached to the electrode layer; a layer of thin film material attached to the outside of the cantilever beam structure; Wherein, the cantilever beam structure is one of the following: a single-sided piezoelectric cantilever beam, a double-sided piezoelectric cantilever beam or a cantilever bridge structure, and the thin film material layer and / or the piezoelectric material layer constitute a single-sided film structure or a double-sided film structure.

3. The microactuator according to claim 1, characterized in that: The driving component is a single-sided membrane structure or a double-sided membrane structure; When it is a single-sided membrane structure, it includes: The piezoelectric film; the electrode layer; and A cantilever beam structure is attached below the electrode layer; When it is a double-sided membrane structure, it includes: An upper film, comprising the piezoelectric film and a first elastic film; A lower film, which is a second elastic film; and The mass block is arranged between the upper membrane and the lower membrane.

4. The microactuator according to claim 1, characterized in that: The outer frame is a rectangular parallelepiped structure or a circular structure; When the outer frame is a circular structure, the cantilever beams in the driving assembly are arranged in a rotationally symmetrical or mirror-symmetrical manner.

5. The microactuator according to claim 1, characterized in that: The peripheral fixing component is made of one or more of the following materials: silicon, silicon dioxide, silicon nitride, aluminum, titanium, polyimide, stainless steel, polydimethylsiloxane, titanium dioxide, silicon carbide, quartz or ceramic material.

6. The microactuator according to claim 1, characterized in that: The piezoelectric film is made of one or more of the following materials: lithium niobate, lead zirconium titanate or potassium sodium niobate.

7. The microactuator according to any one of claims 1 to 6, characterized in that: Also includes: A packaging structure for protecting the piezoelectric film and the electrode layer and providing environmental isolation; The packaging structure and the outer frame form a sealed cavity, and the driving component, the mass block and the peripheral fixing component are all arranged in the sealed cavity.

8. The microactuator according to claim 2, characterized in that: When the cantilever beam structure is a single-sided piezoelectric cantilever beam, the mass block is fixed to the free end of the cantilever beam; When the cantilever beam structure is a bilateral piezoelectric cantilever beam, the mass block is fixed at the middle position of two parallel cantilever beams; When the cantilever beam structure is a cantilever bridge structure, the mass block is fixed at the center position of the cantilever bridge.

9. The microactuator according to claim 1, characterized in that: The size of the microactuator is between 0.1 mm and 10 mm, and can generate a displacement of 0.1-10 μm in a frequency range of 1-100 Hz.

10. Use of the microactuator according to any one of claims 1 to 9 in the following equipment: Tactile feedback devices for AR / VR glasses; tactile output devices for smart rings; precise liquid control devices for microfluidic systems; micro-manipulation tools in the biomedical field; or fine-tuning mechanisms for precision instruments.

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