MEMS controller and MEMS device
By designing a MEMS controller that includes a control unit, a cantilever beam structure, and a diaphragm, unidirectional fluid flow and high-frequency signal demodulation and conversion were achieved, overcoming the shortcomings of fluid control and signal conversion in existing technologies and improving the functionality and efficiency of the equipment.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- AAC KAITAI TECHNOLOGIES (WUHAN) CO LTD
- Filing Date
- 2024-12-24
- Publication Date
- 2026-07-02
AI Technical Summary
There is a lack of effective MEMS controllers in the current technology to realize unidirectional fluid movement and demodulation conversion of high-frequency signals.
A MEMS controller was designed, comprising a control unit, a cantilever beam structure, a diaphragm, and a packaging structure. Unidirectional flow control of fluid is achieved through the gaps between the cantilever beam structures, and demodulation and conversion of high-frequency signals are achieved through the diaphragm and packaging structure.
It achieves unidirectional flow control of fluids and efficient demodulation and conversion of high-frequency signals, making it suitable for heat sinks and speakers, and improving the functionality and efficiency of the equipment.
Smart Images
Figure CN2024141903_02072026_PF_FP_ABST
Abstract
Description
MEMS controllers and MEMS devices Technical Field
[0001] The present invention relates to the field of control devices, and particularly to a MEMS controller and a MEMS device. Background Technology
[0002] MEMS (Micro-Electro-Mechanical System), also known as micro-electromechanical system or microsystem, refers to high-tech devices with dimensions of a few millimeters or even smaller, whose internal structures are generally at the micrometer or even nanometer scale. MEMS is an independent intelligent system, developed based on microelectronics technology (semiconductor manufacturing technology), integrating technologies such as photolithography, etching, thin film, LIGA, silicon micromachining, non-silicon micromachining, and precision machining.
[0003] MEMS technology is widely used in various fields, including but not limited to: consumer electronics products, such as miniature speakers and MEMS microphones. These products are widely used in devices such as laptops and smartphones due to their advantages of small size, low power consumption and mass production.
[0004] There is a need to provide a MEMS controller for controlling unidirectional fluid movement. Summary of the Invention
[0005] This invention provides a MEMS controller and a MEMS device that can at least control the unidirectional movement of fluid.
[0006] According to some embodiments of the present invention, one aspect of the present invention provides a MEMS controller, comprising: at least one control unit, the control unit comprising: two first anchor point structures, adjacent first anchor point structures having a first gap, the first anchor point structures having opposing bottom surfaces and top surfaces; a cantilever beam structure corresponding to the first anchor point structures, the cantilever beam structure having opposing first ends and second ends, and the first end of each cantilever beam structure being located on the top surface of the corresponding first anchor point structure, the second ends of two adjacent cantilever beam structures of the same control unit being directly opposite each other and having a second gap; two second anchor point structures, one second anchor point structure contacting one first anchor point structure, and the other second anchor point structure being located on the top surface of the first anchor point structure. The two anchor point structures are located on the side away from the first anchor point structure; a diaphragm covers the top surfaces of the two second anchor point structures; an encapsulation structure includes a bottom plate, a side plate, and a top plate connected in sequence, the bottom plate and the top plate facing each other, and the side plate connecting the bottom plate and the top plate; wherein, the bottom plate is located on the bottom surface of the first anchor point structure and the second anchor point structure, and the bottom plate is provided with a first flow channel opening penetrating the bottom plate, the first flow channel opening corresponding to the control unit, and the first flow channel opening communicating with the first gap of the corresponding control unit; the top plate is spaced apart from the top surface of the cantilever beam structure and the diaphragm, and the top plate is provided with a second flow channel opening penetrating the top plate, the second flow channel opening corresponding to the control unit.
[0007] In some embodiments, within the same control unit, at least one of the cantilever beam structures has the same vibration frequency as the diaphragm, but the initial phase of the cantilever beam structure is different from the initial phase of the diaphragm.
[0008] In some embodiments, the distance between the center of the second flow channel and the second end of the cantilever beam structure near the second flow channel is 100 μm to 5000 μm.
[0009] In some embodiments, the height of the first anchor structure is the same as the height of the second anchor structure.
[0010] In some embodiments, the height of the second anchor structure is 100μm to 5000μm.
[0011] In some embodiments, the thickness of the cantilever beam structure is equal to the thickness of the diaphragm.
[0012] In some embodiments, the number of control units is greater than or equal to two, and the two second anchor point structures within the same control unit are in contact with the first anchor point structure of the adjacent control unit.
[0013] In some embodiments, the number of control units is greater than or equal to two, and one of the two second anchor point structures within the same control unit is in contact with the first anchor point structure, while the other is in contact with the second anchor point structure of another control unit.
[0014] According to some embodiments of the present invention, another aspect of the present invention also provides a MEMS device, including the MEMS controller as described above.
[0015] The technical solution provided by the embodiments of the present invention has at least the following advantages: When the MEMS device is part of a heat sink, the diaphragm vibrates to draw in cooling fluid from one of the first or second flow channels, then through the gap between the cantilever beam structures, and out through the other of the first or second flow channels to complete the unidirectional flow control of the gas. When the MEMS device is part of a loudspeaker, the diaphragm vibrates to generate a high-frequency signal. The sound channel formed by the encapsulation structure, the cantilever beam structure, the first anchor point structure, and the diaphragm can demodulate the high-frequency signal, thereby converting the high-frequency signal into a low-frequency signal to output the frequency of human-audible sound. The encapsulation structure serves as the protective shell of the control unit and forms a flow channel, thereby facilitating the output of cooling fluid or the demodulation of sound. Attached Figure Description
[0016] One or more embodiments are illustrated by way of example with corresponding pictures in the accompanying drawings. These illustrative descriptions do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 is a schematic diagram of the structure of a MEMS controller provided by the present invention;
[0018] Figure 2 is a graph showing the relationship between the height of the second anchor point structure and the flow rate per unit chip volume provided by the present invention.
[0019] Figure 3 is a graph showing the relationship between the first distance and the flow rate per unit chip volume provided by the present invention.
[0020] Figure 4 shows an arrangement of a control unit according to an embodiment of the present invention;
[0021] Figure 5 shows another arrangement of the control unit provided in an embodiment of the present invention;
[0022] Figure 6 shows another arrangement of the control unit provided in an embodiment of the present invention;
[0023] Figure 7 is a schematic diagram of the structure of the first flow channel as a fluid outlet;
[0024] Figure 8 is a schematic diagram of the structure of the second flow channel as a fluid outlet;
[0025] Figure 9 shows the displacement time-domain diagram of the diaphragm center;
[0026] Figure 10 is a flow rate time domain diagram of the fluid flowing out through the second flow channel;
[0027] Figure 11 is a schematic diagram of the structure of the second flow channel as a sound outlet;
[0028] Figure 12 is a schematic diagram of the structure of the first flow channel as a sound outlet;
[0029] Figure 13 shows the spectrum of the ultrasonic signal generated by the diaphragm;
[0030] Figure 14 is a spectrum of sound pressure at the sound outlet;
[0031] Figure 15 is a schematic diagram of the simulated sound-emitting process. Embodiments of the present invention
[0032] As can be seen from the background technology, there is a need to provide a MEMS controller to control unidirectional fluid flow.
[0033] This invention provides a MEMS controller and a MEMS device. When the MEMS device is part of a heat sink, the diaphragm vibrates to draw in cooling fluid from one of the first or second flow channels, then through the gap between the cantilever beam structures, and out through the other of the first or second flow channels to achieve unidirectional gas flow control. When the MEMS device is part of a loudspeaker, the diaphragm vibrates to generate a high-frequency signal. The sound channel formed by the encapsulation structure, the cantilever beam structure, the first anchor point structure, and the diaphragm can demodulate the high-frequency signal, thereby converting the high-frequency signal into a low-frequency signal to output the frequency of human-audible sound. The encapsulation structure serves as a protective shell for the control unit and encloses the flow channel, thereby facilitating the output of cooling fluid or the demodulation of sound.
[0034] In the description of the embodiments of this invention, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this invention, "multiple" means two or more, unless otherwise explicitly defined.
[0035] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0036] In the description of the embodiments of this invention, the term "and / or" is merely a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists, A and B exist simultaneously, and B exists. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.
[0037] In the description of the embodiments of the present invention, the term "multiple" refers to two or more (including two), similarly, "multiple groups" refers to two or more (including two groups), and "multiple pieces" refers to two or more (including two pieces).
[0038] In the description of the embodiments of the present invention, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention.
[0039] In the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances.
[0040] In the accompanying drawings corresponding to the embodiments of the present invention, the thickness and area of the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or lens body) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.
[0041] In the description of embodiments of the present invention, when a component "includes" another component, other components are not excluded unless otherwise stated, and may be further included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on / located" on another component, it can be "directly" on the other component (i.e., located on the surface of the other component with no other components between them), or another component may be present therein. Moreover, when a component such as a layer, film, region, or plate is "directly located" on another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it indicates that no other components are located therein.
[0042] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "component" is also intended to include the plural form unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.
[0043] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of the present invention to facilitate a better understanding of the invention. However, the technical solutions claimed in this invention can be implemented even without these technical details and various variations and modifications based on the following embodiments.
[0044] Referring to Figure 1, Figure 1 is a schematic diagram of the structure of a MEMS controller provided by the present invention.
[0045] In some embodiments, the MEMS controller may include: at least one control unit 100, the control unit 100 including: two first anchor structures 110, adjacent first anchor structures 110 having a first gap 120, the first anchor structures 110 having opposing bottom surfaces and top surfaces; a cantilever beam structure 130 corresponding to the first anchor structures 110, the cantilever beam structure 130 having opposing first ends and second ends, and the first end of each cantilever beam structure 130 being located on the top surface of the corresponding first anchor structure 110, the second ends of two adjacent cantilever beam structures 130 of the same control unit 100 being directly opposite each other and having a second gap 140; two second anchor structures 150, one second anchor structure 150 contacting one first anchor structure 110, the other second anchor structure 150 being located on the side of the second anchor structure 150 away from the first anchor structure 110; and a diaphragm 160 covering the top surfaces of the two second anchor structures 150.
[0046] The MEMS controller may further include: a packaging structure 101, which includes a base plate 111, a side plate 121, and a top plate 131 connected in sequence. The base plate 111 and the top plate 131 face each other, and the side plate 121 connects the base plate 111 and the top plate 131. The base plate 111 is located on the bottom surface of the first anchor point structure 110 and the second anchor point structure 150, and the base plate 111 is provided with a first flow channel 141 penetrating the base plate 111. The first flow channel 141 corresponds to the control unit 100 and is connected to the first gap 120 of the corresponding control unit 100. The top plate 131 is spaced apart from the top surface of the cantilever beam structure 130 and the diaphragm 160, and the top plate 131 is provided with a second flow channel 151 penetrating the top plate 131. The second flow channel 151 corresponds to the control unit 100.
[0047] This invention provides a MEMS controller. When the MEMS device is part of a heat sink, the diaphragm 160 vibrates to draw in cooling fluid from either the first flow channel 141 or the second flow channel 151. The fluid then flows through the gap between the cantilever beam structures 130 and out through the other of the first flow channel 141 or the second flow channel 151, thus achieving unidirectional gas flow control. When the MEMS device is part of a loudspeaker, the diaphragm 160 vibrates to generate a high-frequency signal. The sound channel formed by the encapsulation structure 101, the cantilever beam structure 130, the first anchor point structure 110, and the diaphragm 160 can demodulate the high-frequency signal, thereby converting the high-frequency signal into a low-frequency signal to output a frequency that is audible to humans. The encapsulation structure 101 serves as a protective shell for the control unit 100 and forms a flow channel, thereby facilitating the output of cooling fluid or the demodulation of sound.
[0048] The control unit can be fabricated using MEMS technology or other precision technologies.
[0049] The first anchor point structure 110 can be used to support the cantilever beam structure 130. The top surface of the first anchor point structure 110 is fixedly connected to the first end of the cantilever beam structure 130. The first anchor point structure 110, the cantilever beam structure 130 and the encapsulation structure 101 together form a flow channel so that fluid flows through the flow channel and flows out from the second flow channel port 151 or the first flow channel port 141.
[0050] In some embodiments, the cantilever beam structure 130 may also vibrate during the operation of the MEMS controller, thereby assisting in the movement of fluid or in sound demodulation. For example, if the MEMS controller needs to perform heat dissipation, the vibration of the cantilever beam structure 130 can cooperate with the diaphragm 160 to increase the flow rate of the fluid.
[0051] The first anchor point structure 110 can drive the cantilever beam structure 130 in the following ways: piezoelectric drive, electrostatic drive, thermoelectric drive, or electromagnetic drive, etc. Taking piezoelectric drive as an example, the inverse piezoelectric effect of piezoelectric materials is used to convert electrical energy into mechanical energy to drive the cantilever beam structure 130 to vibrate.
[0052] In some embodiments, the first anchor structure 110 may be a control layer for an SOI (Silicon-On-Insulator) chip. The first anchor structure 110 may also be a control layer for other types of chips, which can be used in conjunction with the drive cantilever beam structure 130.
[0053] In some embodiments, during the operation of the MEMS controller, the two first anchor point structures 110 can be selected to control one of them to control the vibration of the corresponding cantilever beam structure 130, or both first anchor point structures 110 can control the vibration of the cantilever beam structure 130. The working time or working state of the first anchor point structure 110 can be selected according to different working requirements.
[0054] In some embodiments, within the same control unit 100, at least one cantilever beam structure 130 has the same vibration frequency as the diaphragm 160, but the initial phase of the cantilever beam structure 130 is different from that of the diaphragm 160. It is understood that, taking the second flow channel 151 as the fluid inlet as an example, when fluid is drawn into the MEMS controller due to the vibration of the diaphragm 160, the fluid movement requires a certain amount of time. Therefore, when the fluid reaches above the cantilever beam structure 130, a certain amount of time is needed. Thus, by controlling the initial phase of the cantilever beam structure 130 to be different from the initial phase of the diaphragm 160, the fluid above the second gap 140 can be drawn back into the cantilever beam structure 130 through the cooperation of the cantilever beam structure 130 and the diaphragm 160, thereby accelerating the fluid and enhancing the heat dissipation effect. When the MEMS controller needs to perform sound dissipation, the vibration of the diaphragm 160, the channel structure, and the cantilever beam structure 130 can be used to demodulate the sound, realizing the sound dissipation function of the MEMS controller.
[0055] In some embodiments, the initial phase of the cantilever beam structure 130 and the initial phase of the diaphragm 160 may differ by 5° or 10°, etc. It is understood that the optimal combination and cooperation between the cantilever beam structure 130 and the diaphragm 160 can be determined by calculation and simulation to determine the optimal difference between the initial phase of the cantilever beam structure 130 and the initial phase of the diaphragm 160.
[0056] In some embodiments, within the same control unit 100, the vibration frequency of the cantilever beam structure 130 is the same as the vibration frequency of the diaphragm 160, and the initial phase of the cantilever beam structure 130 is the same as the initial phase of the diaphragm 160. In this way, the control difficulty of the MEMS controller can be reduced, and the vibration of the cantilever beam structure 130 and the diaphragm 160 can be controlled simultaneously by the same control signal.
[0057] In some embodiments, the initial phase of the cantilever beam structure 130 can also be adjusted to control the flow rate of the fluid flowing out via the MEMS controller. For example, when the fluid flow rate is too fast, the initial phase of the cantilever beam structure 130 can be adjusted to interfere with the diaphragm 160 drawing in fluid, thereby reducing the rate at which the fluid flows out via the MEMS controller.
[0058] The two cantilever beam structures 130 can be controlled individually or simultaneously. During the operation of the MEMS controller, only one of the cantilever beam structures 130 can be controlled, or the vibration of both cantilever beam structures 130 can be controlled simultaneously.
[0059] In some embodiments, the vibrations of the two cantilever beam structures 130 can satisfy the same initial phase, vibration frequency, and amplitude; in other embodiments, the vibration frequencies and amplitudes of the two cantilever beam structures 130 are the same, but the initial phases are different.
[0060] In some embodiments, the cantilever beam structure 130 can also have the opposite effect to the diaphragm 160, for example, by reducing the flow rate of the fluid passing through the second gap 140 through the cantilever beam structure 130, thereby achieving control of the fluid flow rate.
[0061] The cantilever beam structure 130 and the first anchor point structure 110 can also be non-functional support layers, used only to construct channels for fluid flow or to construct sound channels.
[0062] The second anchor structure 150 can be used to support the diaphragm 160. The second anchor structure 150, the first anchor structure 110, the cantilever beam structure 130 and the encapsulation structure 101 together form a flow channel so that fluid enters the flow channel and flows out from the second flow channel port 151 or the first flow channel port 141.
[0063] The second anchor structure 150 can drive the diaphragm 160 in the following ways: piezoelectric drive, electrostatic drive, thermoelectric drive, or electromagnetic drive, etc. Taking piezoelectric drive as an example, the inverse piezoelectric effect of piezoelectric materials is used to convert electrical energy into mechanical energy to drive the diaphragm 160 to vibrate.
[0064] The second anchor structure 150 can be a control layer for an SOI (Silicon-On-Insulator) chip. The second anchor structure 150 can also be a control layer for other types of chips, which can be used in conjunction with the drive diaphragm 160.
[0065] In some embodiments, the height of the first anchor structure 110 is the same as the height of the second anchor structure 150. That is, the distance between the cantilever beam structure 130 and the top plate 131 is equal to the distance between the diaphragm 160 and the top plate 131, so that the state of the fluid does not change when fluid flows from the space between the diaphragm 160 and the top plate 131 into the space between the cantilever beam structure 130 and the top plate 131.
[0066] In some embodiments, the height of the first anchor structure 110 may also be less than the height of the second anchor structure 150. Since the second flow channel 151 is directly opposite the diaphragm 160 and is relatively close to it, when the second flow channel 151 serves as the fluid inlet, the flow velocity of the fluid entering the MEMS controller through the second flow channel 151 will be relatively high. Therefore, setting the height of the first anchor structure 110 to be less than the height of the second anchor structure 150 allows the fluid velocity to decrease when flowing from the space between the diaphragm 160 and the top plate 131 into the space between the cantilever beam structure 130 and the top plate 131. This facilitates controlling the fluid to flow at a suitable speed from the first flow channel 141. When the second flow channel 151 serves as the fluid outlet, the flow velocity of the fluid entering the MEMS controller through the first flow channel 141 will be relatively low due to the greater distance between the first flow channel 141 and the diaphragm 160. By setting the height of the first anchor structure 110 to be less than the height of the second anchor structure 150, the fluid velocity can be increased when the fluid enters the space between the diaphragm 160 and the top plate 131 from the space between the cantilever beam structure 130 and the top plate 131, thereby facilitating the control of the fluid to flow out of the second flow channel 151 at a suitable speed.
[0067] In some embodiments, the height of the second anchor structure 150 is 100μm to 5000μm, for example, 300μm, 500μm, 1000μm, 1800μm, 2500μm, 3000μm, 4000μm, or 4600μm, etc. Referring to Figure 2, which is a graph showing the relationship between the height of the second anchor structure and the flow rate per unit chip volume provided by the present invention, for the second anchor structure 150, the height of the second anchor structure 150 is positively correlated with the net flow rate of the driving fluid of the MEMS controller. That is, the greater the height of the second anchor structure 150, the greater the net flow rate of the fluid that the MEMS controller can pass through. However, a greater height of the second anchor structure 150 will make the overall size of the MEMS controller larger, and a greater height of the second anchor structure 150 will also result in a lower net flow rate per unit chip volume, leading to the... The second anchor structure 150 suffers from performance waste. Although the net flow rate of the fluid that the MEMS controller can pass through decreases as the height of the second anchor structure 150 decreases, the net flow rate per unit chip volume increases. In other words, the performance utilization rate of the second anchor structure 150 increases. However, as the height of the second anchor structure 150 decreases, the fabrication process of the MEMS controller becomes more difficult. Therefore, the height of the second anchor structure 150 is set to 100μm~5000μm, which improves the net flow rate per unit chip volume while taking into account the fabrication process difficulty of the MEMS controller.
[0068] It should be noted that the flow rate per unit chip volume here refers to the total flow rate of fluid output through the MEMS controller per unit time divided by the planar area of the MEMS controller.
[0069] In some embodiments, the first anchor structure 110 and the second anchor structure 150 are made of the same material and have the same structure, and can be formed in the same process step, thereby reducing the process steps in forming the MEMS controller and reducing the cost of the MEMS controller.
[0070] The vibration frequency of the diaphragm 160 is greater than or equal to 20KHz, such as 30KHz, 50KHz or 100KHz, etc. The vibration frequency of the diaphragm 160 is greater than or equal to 20KHz, which can increase the flow rate of the fluid flowing in or out through the first flow channel 141.
[0071] The diaphragm 160 can be a rectangle, a circle, or a hexagon, etc.
[0072] In some embodiments, the thickness of the cantilever beam structure 130 is equal to the thickness of the diaphragm 160. This allows the cantilever beam structure 130 and the diaphragm 160 to be formed in the same process step, thereby reducing the number of process steps required to form the MEMS controller and lowering its cost.
[0073] When the first anchor structure 110 and the second anchor structure 150 have the same height, by controlling the thickness of the cantilever beam structure 130 to be equal to the thickness of the diaphragm 160, the distance between the cantilever beam structure 130 and the top plate 131 can be controlled to be equal to the distance between the diaphragm 160 and the top plate 131.
[0074] The encapsulation structure 101 can be used to protect the control unit 100, to extract signals, or to transmit control signals to the control unit 100, thereby completing signal transmission. The encapsulation structure 101 can also be used to construct fluid channels, for example, to construct gas channels to control gas to enter from the first channel port 141 and exit from the second channel port 151, or to control gas to enter from the second channel port 151 and exit from the first channel port 141.
[0075] In some embodiments, the packaging structure 101 may be a metal plate or a PCB, etc.
[0076] In some embodiments, the second flow channel 151 may be directly opposite the diaphragm 160 and offset from the second gap 140; in other embodiments, the second flow channel 151 may be offset from the diaphragm and directly opposite the second gap 140.
[0077] In some embodiments, the distance between the center of the second flow channel 151 and the second end of the cantilever beam structure 130 near the second flow channel 151 is 100 μm to 5000 μm. The distance between the center of the second flow channel 151 and the second end of the cantilever beam structure 130 near the second flow channel 151 is defined as the first distance L1. Referring to Figure 3, which is a graph showing the relationship between the first distance and the flow rate per unit chip volume provided by the present invention, for a MEMS controller, the first distance L1 is positively correlated with the net flow rate of the driving fluid through the MEMS control area. That is, the longer the first distance L1, the greater the net flow rate of the fluid that the MEMS controller can pass through. However, a longer first distance L1 will result in a larger overall size of the MEMS controller. Furthermore, the first distance L... The longer the first distance L1 is, the lower the net flow rate per unit chip volume will be, resulting in wasted MEMS controller size. The shorter the first distance L1 is, the lower the net flow rate of the fluid that the MEMS controller can pass through will be, but the net flow rate per unit chip volume will be increased. In other words, the volume utilization rate of the MEMS controller will be increased. Similarly, as the first distance L1 decreases, the manufacturing process difficulty of the MEMS controller will increase. Therefore, the first distance L1 is set to 100μm~5000μm, which improves the net flow rate per unit chip volume while taking into account the manufacturing process difficulty of the MEMS controller.
[0078] It should be noted that the center of the second flow channel 151 mentioned here can refer to the geometric center of the second flow channel 151. If the second flow channel 151 is circular, then the center mentioned here is the center of the circle. If the second flow channel 151 is square, then the center mentioned here is the center of axial symmetry of the square.
[0079] In some embodiments, the first flow channel 141 is directly opposite the second gap 140. In this way, the fluid flowing from the second gap 140 to the first flow channel 141, or from the first flow channel 141 to the second gap 140, will experience reduced losses during the flow process, and the noise during fluid flow will also be reduced, thereby improving the performance of the MEMS controller.
[0080] In some embodiments, in the direction in which the first anchor structure 110 is arranged, the width of the first flow channel 141 is greater than or equal to the width of the second gap 140. That is, within the same control unit 100, the width of the first flow channel 141 is greater than or equal to the distance between the two cantilever beam structures 130. Thus, if the fluid enters from the second gap 140 and exits from the first flow channel 141, fluid loss can be reduced. If the fluid enters from the first flow channel 141 and exits from the second gap 140, the reduction in the outlet size will increase the kinetic energy of the fluid, thereby increasing the fluid velocity.
[0081] In some embodiments, in the arrangement direction of the first anchor point structure 110, the width of the second flow channel 151 is less than the width of the second gap 140, and the distance between the top plate 131 and the cantilever beam structure 130 is less than the distance between the bottom plate 111 and the cantilever beam structure 130. If the second flow channel 151 is used as a fluid outlet, a smaller width for the second flow channel 151 can increase the velocity of the fluid flowing out of the second flow channel 151. Similarly, setting the distance between the top plate 131 and the cantilever beam structure 130 to be smaller than the distance between the bottom plate 111 and the cantilever beam structure 130 reduces the fluid outlet diameter, thus increasing the velocity of the fluid flowing out of the second flow channel 151. If the second flow channel 151 is used as a fluid inlet, a smaller width for the second flow channel 151 allows the fluid to have a better initial velocity when entering the MEMS device and reduces noise generated by the fluid within the MEMS device. Furthermore, setting the distance between the top plate 131 and the cantilever beam structure 130 to be smaller than the distance between the bottom plate 111 and the cantilever beam structure 130 increases the fluid outlet diameter, reducing fluid loss and noise within the MEMS device.
[0082] Referring to Figures 1 and 4, Figure 4 shows an arrangement of a control unit according to an embodiment of the present invention.
[0083] In some embodiments, the number of control units 100 is greater than or equal to two, and the two second anchor structures 150 within the same control unit 100 are in contact with the first anchor structure 110 of the adjacent control unit 100. In other words, the arrangement direction of the first anchor structure 110 and the second anchor structure within each control unit 100 is the same. For example, the first anchor structure 110 within each control unit 100 is located on the same side of the second anchor structure 150. By controlling the two second anchor structures 150 within the same control unit 100 to be in contact with the first anchor structure 110 of the adjacent control unit 100, the process difficulty of forming the MEMS controller can be reduced.
[0084] Referring to Figures 1, 5 and 6, Figure 5 shows another arrangement of the control unit provided in an embodiment of the present invention, and Figure 6 shows yet another arrangement of the control unit provided in an embodiment of the present invention.
[0085] In some embodiments, the number of control units 100 is greater than or equal to two. Within the same control unit 100, one of the two second anchor structures 150 contacts the first anchor structure 110, and the other contacts the second anchor structure 150 of another control unit 100. In other words, the arrangement directions of the first anchor structures 110 and second anchor structures 150 within adjacent control units 100 are different. For example, in two adjacent control units 100, the first anchor structure 110 in one control unit 100 is located on one side of the second anchor structure 150, and the first anchor structure 110 in the other control unit 100 is located on the other side of the second anchor structure 150. For a MEMS controller with multiple control units 100, setting one of the two second anchor structures 150 within the same control unit 100 to contact the first anchor structure 110 and the other to contact the second anchor structure 150 of another control unit 100 can improve the control effect of the MEMS controller. For example, it can improve the reliability of MEMS control of unidirectional airflow or improve the reliability of MEMS sound demodulation.
[0086] Referring to Figure 5, in some embodiments, the number of control units 100 is greater than or equal to two. The diaphragm 160 of the control unit 100 that contacts the side plate 121 is located on the side of the cantilever beam structure 130 away from the side plate 121. In this way, the fluid inlet or outlet can be set in the part of the MEMS controller near the center, which can improve the stress resistance of the packaging structure 101 and improve the reliability of the MEMS controller.
[0087] Referring to Figure 6, in some embodiments, the number of control units 100 is greater than or equal to two. The diaphragm 160 of the control unit 100 that contacts the side plate 121 is located on the side of the cantilever beam structure 130 near the side plate 121. In this way, the fluid inlet or outlet can be set at different positions of the MEMS controller. Taking the fluid flowing out from the second flow channel 151 as an example, the dead zone of the fluid flowing out of the MEMS controller can be reduced.
[0088] It should be noted that the aforementioned dead zone refers to the area that cannot be covered after the fluid flows out.
[0089] In some embodiments, the diaphragms 160 within different control units 100 have the same initial vibration phase and the same vibration frequency. In other embodiments, the initial vibration phase, vibration frequency, and / or amplitude of the diaphragms 160 within different control units 100 may also be different, and the vibration of the diaphragms 160 within different control units 100 can be adjusted according to actual needs.
[0090] The following will describe in detail the working process of the MEMS controller when it provides heat dissipation capability, with reference to Figures 7 to 10. Figure 7 is a schematic diagram of the structure of the first flow channel as the fluid outlet, Figure 8 is a schematic diagram of the structure of the second flow channel as the fluid outlet, Figure 9 is a time-domain diagram of the displacement of the diaphragm center, and Figure 10 is a time-domain diagram of the flow rate of the fluid flowing out through the second flow channel.
[0091] Referring to Figures 7, 9 and 10, when the MEMS controller needs to provide heat dissipation, it controls the diaphragm 160 to vibrate. The cold fluid flows in from the second flow channel 151, passes through the second gap 140 and the first gap 120 in sequence, and flows out through the first flow channel 141. The first flow channel 141 can be directly opposite the structure that needs to be cooled, so that the cold fluid impacts the surface of the structure that needs to be cooled, thereby completing the heat dissipation and cooling process.
[0092] In some embodiments, the vibration of the diaphragm 160 within the control unit 100 satisfies: d s =d1Sin(2πf0t), where d1 represents the amplitude of the diaphragm 160 vibration and f0 represents the operating frequency of the MEMS controller.
[0093] In some embodiments, during the operation of the MEMS controller, the vibration of the cantilever beam structure 130 can also be controlled, and the vibration of the cantilever beam structure 130 satisfies: d s =d1Sin(2πf0t+∆φ),∆φ represents the initial phase difference between the cantilever beam structure 130 and the diaphragm 160 vibrating within the same control unit 100.
[0094] Referring to Figure 10, when the cantilever beam structure 130 is not vibrating, the flow rate time-domain diagram of the fluid flowing into the second flow channel 151 can be shown in Figure 10a. Alternatively, when the vibration of the cantilever beam structure 130 does not interfere with the vibration effect of the diaphragm 160, the flow rate time-domain diagram of the fluid flowing into the second flow channel 151 can be shown in Figure 10a. When the cantilever beam structure 130 vibrates and interferes with the vibration effect of the diaphragm 160, the flow rate time-domain diagram of the fluid flowing into the second flow channel 151 can be shown in Figure 10b.
[0095] The present invention can control the unidirectional flow of fluid through a MEMS controller, and the velocity of the fluid flowing into the second flow channel 151 can be no less than 20m / s.
[0096] Referring to Figures 8 to 10, when the MEMS controller needs to provide heat dissipation, it controls the diaphragm 160 to vibrate. Cold fluid flows in from the first flow channel 141, passes through the second gap 140 and the first gap 120 in sequence, and flows out through the second flow channel 151. The second flow channel 151 can be directly opposite the structure that needs to be cooled, so that the cold fluid impacts the surface of the structure that needs to be cooled, thereby completing the heat dissipation and cooling process.
[0097] In some embodiments, the vibration of the diaphragm 160 within the control unit 100 satisfies: d s =d1Sin(2πf0t), where d1 represents the amplitude of the diaphragm 160 vibration and f0 represents the operating frequency of the MEMS controller.
[0098] In some embodiments, during the operation of the MEMS controller, the vibration of the cantilever beam structure 130 can also be controlled, and the vibration of the cantilever beam structure 130 satisfies: d s =d1Sin(2πf0t+∆φ),∆φ represents the initial phase difference between the cantilever beam structure 130 and the diaphragm 160 vibrating within the same control unit 100.
[0099] Referring to Figure 10, when the cantilever beam structure 130 is not vibrating, the flow rate time-domain diagram of the fluid flowing out of the second flow channel 151 can be shown in Figure 10c. Alternatively, when the vibration of the cantilever beam structure 130 does not interfere with the vibration effect of the diaphragm 160, the flow rate time-domain diagram of the fluid flowing out of the second flow channel 151 can be shown in Figure 10c. When the cantilever beam structure 130 vibrates and interferes with the vibration effect of the diaphragm 160, the flow rate time-domain diagram of the fluid flowing into the second flow channel 151 can be shown in Figure 10d.
[0100] The present invention can control the unidirectional flow of fluid through a MEMS controller, and the velocity of the fluid flowing into the second flow channel 151 can be no less than 20m / s.
[0101] This invention does not limit the fluid; the fluid can be liquid, gas, sound waves, etc.
[0102] The following will describe in detail the working process of the MEMS controller when it is used for sound dissemination, with reference to Figures 11 to 15. Figure 11 is a schematic diagram of the structure of the second flow channel as the sound outlet, Figure 12 is a schematic diagram of the structure of the first flow channel as the sound outlet, Figure 13 is a spectrum diagram of the ultrasonic signal generated by the diaphragm, Figure 14 is a spectrum diagram of the sound pressure at the sound outlet, and Figure 15 is a schematic diagram of the simulated structure of the sound dissemination process.
[0103] When the sound-generating capability is required, the driving signal generated by the second anchoring structure drives the diaphragm 160 to shift, and the displacement of the center of the diaphragm 160 satisfies: d s =d1Sin(2πf0t)Sin(2πf a t), where d1 represents the amplitude of the diaphragm 160 vibration, f0 represents the ultrasonic frequency, and f a This represents the audible sound frequency. When the diaphragm vibrates at 160°, it generates ultrasound, as shown in Figure 13. The sound pressure of ultrasound satisfies u... s =u1Sin(2πf0t)Sin(2πf at), where u1 is the amplitude of the sound pressure. The sound channel formed by this invention will demodulate the sound, that is, amplitude modulation. The amplitude modulation satisfies: u mod =u2Sin(2πf0t), where u2 is the amplitude of the sound pressure, when the ultrasonic signal u s The output sound pressure level u is modulated by the amplitude of this channel. out The output sound pressure satisfies u out= u sX u mod= u1Sin(2πf0t)Sin(2πf a t)Xu2Sin(2πf0t), where X is the multiplication sign, can be used to obtain the audible frequency f. a The frequency spectrum of the output sound pressure is shown in Figure 14. The MEMS provided by this invention can demodulate sound when used for loudspeaker, thereby converting ultrasonic frequencies into audible sound frequencies.
[0104] Another embodiment of the present invention provides a MEMS device, which may include the MEMS controller in some or all of the above embodiments. The MEMS device provided in another embodiment of the present invention will be described below. It should be noted that the same or corresponding parts as those in the foregoing embodiments can be referred to the corresponding descriptions in the foregoing embodiments, and will not be repeated below.
[0105] The MEMS device provided by this invention can be used for heat dissipation or for sound generation.
[0106] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of the embodiments of the present invention. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the embodiments of the present invention; therefore, the scope of protection of the embodiments of the present invention should be determined by the scope defined in the claims.
Claims
1. A MEMS controller, comprising: At least one control unit, the control unit comprising: two first anchor point structures, adjacent first anchor point structures having a first gap, the first anchor point structures having opposing bottom and top surfaces; a cantilever beam structure corresponding to the first anchor point structures, the cantilever beam structure having opposing first and second ends, and the first end of each cantilever beam structure being located on the top surface of the corresponding first anchor point structure, the second ends of two adjacent cantilever beam structures of the same control unit being directly opposite each other and having a second gap; two second anchor point structures, one second anchor point structure contacting one first anchor point structure, the other second anchor point structure being located on the side of the second anchor point structure away from the first anchor point structure; and a diaphragm covering the top surfaces of the two second anchor point structures; The encapsulation structure includes a bottom plate, a side plate, and a top plate connected in sequence, wherein the bottom plate and the top plate face each other, and the side plate connects the bottom plate and the top plate; The base plate is located on the bottom surface of the first anchor point structure and the second anchor point structure, and the base plate is provided with a first flow channel opening that penetrates the base plate. The first flow channel opening corresponds to the control unit and is connected to the first gap of the corresponding control unit. The top plate is spaced apart from the top surface of the cantilever beam structure and the diaphragm, and the top plate is provided with a second flow channel opening that penetrates the top plate. The second flow channel opening corresponds to the control unit.
2. The MEMS controller according to claim 1, wherein, Within the same control unit, at least one of the cantilever beam structures has the same vibration frequency as the diaphragm, but the initial phase of the cantilever beam structure is different from the initial phase of the diaphragm.
3. The MEMS controller according to claim 1, wherein, The distance between the center of the second flow channel opening and the second end of the cantilever beam structure near the second flow channel opening is 100μm~5000μm.
4. The MEMS controller according to claim 1, wherein, The height of the first anchor point structure is the same as the height of the second anchor point structure.
5. The MEMS controller according to claim 1 or 4, wherein, The height of the second anchor point structure is 100μm~5000μm.
6. The MEMS controller according to claim 1, wherein, The thickness of the cantilever beam structure is equal to the thickness of the diaphragm.
7. The MEMS controller according to claim 1, wherein, The number of control units is greater than or equal to two, and the two second anchor point structures within the same control unit are in contact with the first anchor point structure of the adjacent control unit.
8. The MEMS controller according to claim 1, wherein, The number of control units is greater than or equal to two, and one of the two second anchor point structures within the same control unit is in contact with the first anchor point structure, while the other is in contact with the second anchor point structure of another control unit.
9. A MEMS device, comprising: The MEMS controller as described in claim 1.