MEMS chip, manufacturing method thereof and electronic equipment

Abstract

The invention provides an MEMS chip, a manufacturing method thereof and electronic equipment. The MEMS chip comprises: a substrate; the supporting beam is fixed on the base plate; the comb tooth pair comprises a plurality of first comb teeth and a plurality of second comb teeth, the first comb teeth are fixed to the base plate, and the second comb teeth are fixed to the supporting beam; or, the plurality of first comb teeth are fixed on the supporting beam, and the plurality of second comb teeth are fixed on the base plate; the plurality of first comb teeth and the plurality of second comb teeth are arranged in the same direction and are alternately arranged; the first comb teeth comprise at least two conductive layers which are stacked in the thickness direction, the second comb teeth comprise at least one conductive layer, and the at least one conductive layer of the first comb teeth and the at least one conductive layer of the second comb teeth are arranged on the same layer. According to the invention, the MEMS chip adopting the different-plane comb tooth pair and the MEMS chip adopting the coplanar comb tooth pair can be manufactured on the basis of the same process platform.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a MEMS chip and a manufacturing method thereof and an electronic device. Background Art

[0002] Microelectromechanical systems (MEMS) chips are widely used in the fields of optical communications, consumer electronics, etc. MEMS chips may include comb teeth pairs, and their working principle is to use the potential difference loaded on the comb teeth pairs to generate electrostatic force and torque to drive the movement of components on the MEMS chip.

[0003] Comb tooth pairs can be divided into coplanar comb tooth pairs and skew comb tooth pairs. Coplanar comb tooth pairs refer to that the driving comb teeth and the driven comb teeth are arranged on the same layer. Skew comb tooth pairs refer to that the driving comb teeth and the driven comb teeth are arranged on different layers. In view of the different structures of coplanar comb tooth pairs and skew comb tooth pairs, they are usually manufactured based on different process platforms. Therefore, two different process platforms need to be set up to manufacture MEMS chips with coplanar comb tooth structures and MEMS chips with skew comb tooth structures, respectively. Summary of the invention

[0004] In order to solve the above technical problems, the present application provides a MEMS chip and a manufacturing method thereof and an electronic device, which can enable a MEMS chip using an eccentric comb tooth pair and a MEMS chip using a coplanar comb tooth pair to be manufactured based on the same process platform.

[0005] In a first aspect of the present application, a MEMS chip is provided, comprising: a substrate, a support beam and a comb tooth pair. The support beam is connected to the substrate and has a suspended portion.

[0006] The comb teeth pair includes a plurality of first comb teeth and a plurality of second comb teeth. In one possible implementation, the plurality of first comb teeth are fixed on the substrate, and the plurality of second comb teeth pairs are fixed on the suspended portion. In another possible implementation, the plurality of first comb teeth are fixed on the suspended portion, and the plurality of second comb teeth are fixed on the substrate.

[0007] The plurality of first comb teeth are arranged in a direction perpendicular to the thickness direction of the MEMS chip, the plurality of second comb teeth are arranged in a direction perpendicular to the thickness direction, the plurality of first comb teeth and the plurality of second comb teeth are arranged in the same direction and alternately. The first comb teeth include at least two conductive layers stacked in the thickness direction, the second comb teeth include at least one conductive layer, and the at least one conductive layer of the first comb teeth and the at least one conductive layer of the second comb teeth are arranged in the same layer.

[0008] Since the first comb teeth include at least two conductive layers, when manufacturing the first comb teeth, the at least two conductive layers can be manufactured separately by a process of first deposition and then etching. At least one conductive layer of the second comb teeth is arranged on the same layer as at least one conductive layer of the first comb teeth. Therefore, the second comb teeth can be manufactured at the same time as the first comb teeth. In other words, the first comb teeth and the second comb teeth can be manufactured on the same process platform and in the same process, thereby reducing the complexity of the manufacturing process of the MEMS chip and reducing the manufacturing cost.

[0009] In addition, when the MEMS chip is used, different voltage signals can be provided to at least two stacked conductive layers, so that the same MEMS chip can realize multiple different functions, thereby improving the integration of the MEMS chip.

[0010] In some possible implementations, the comb tooth pair is a coplanar comb tooth pair, then, the second comb tooth includes at least two conductive layers, the number of conductive layers of the first comb tooth is the same as the number of conductive layers of the second comb tooth, and the at least two conductive layers of the first comb tooth and the at least two conductive layers of the second comb tooth are respectively arranged in the same layer. Exemplarily, the number of conductive layers in the first comb tooth and the second comb tooth are both two, three or more layers. In this way, when making the comb tooth pair, at least two polysilicon layers and an insulating layer located between two adjacent polysilicon layers can be respectively made by deposition, and then the first comb tooth and the second comb tooth can be etched out by etching. Therefore, the first comb tooth and the second comb tooth can be made on the same process platform, and the first comb tooth and the second comb tooth can be made at the same time.

[0011] The second comb teeth may include a third conductive layer and a fourth conductive layer, wherein the first conductive layer and the third conductive layer are disposed in the same layer, and the second conductive layer and the fourth conductive layer are disposed in the same layer. The thickness of the third conductive layer may be the same as that of the first conductive layer, and the thickness of the fourth conductive layer may be the same as that of the second conductive layer.

[0012] In some other possible implementations, the comb tooth pair is a skew comb tooth pair, the second comb tooth includes a conductive layer, and the at least two conductive layers of the first comb tooth include a first conductive layer and a second conductive layer. The conductive layer of the second comb tooth is arranged on the same layer as the first conductive layer, or the conductive layer of the second comb tooth is arranged on the same layer as the second conductive layer. In this way, when making the comb tooth pair, at least two polysilicon layers and an insulating layer located between two adjacent polysilicon layers can be respectively made by deposition, and then the first comb tooth and the second comb tooth can be etched out by etching. Therefore, the first comb tooth and the second comb tooth can be made on the same process platform, and the first comb tooth and the second comb tooth can be made at the same time.

[0013] Regarding the relationship between the thickness of the first conductive layer and the thickness of the second conductive layer, in a possible implementation, the thickness of the first conductive layer is the same as the thickness of the second conductive layer. When the second comb teeth include a third conductive layer and a fourth conductive layer, the thickness of the third conductive layer is also the same as the thickness of the fourth conductive layer.

[0014] In another possible implementation, the thickness of the first conductive layer is different from the thickness of the second conductive layer. When the second comb teeth include a third conductive layer and a fourth conductive layer, the thickness of the third conductive layer is also different from the thickness of the fourth conductive layer.

[0015] The MEMS chip may further include a plurality of signal electrodes, each of which may receive a different voltage signal, and some of the signal electrodes may receive the same voltage signal.

[0016] Regarding the structure of the MEMS chip, in a possible implementation, the number of the fixing parts and the number of the comb tooth pairs are both two, the two fixing parts are respectively located on opposite sides of the support beam, and each comb tooth pair is correspondingly fixed between each fixing part and the support beam.

[0017] In another possible implementation, there are four fixing portions and four comb tooth pairs, the four fixing portions are arranged in a rectangular array on the periphery of the support beam, and a comb tooth pair is connected between each fixing portion and the support beam.

[0018] When the first comb teeth include the first conductive layer and the second conductive layer, and the second comb teeth include the third conductive layer and the fourth conductive layer, the first conductive layer and the fourth conductive layer are respectively connected to different signal electrodes, and the second conductive layer and the third conductive layer are respectively connected to different signal electrodes. In this way, the first conductive layer and the second conductive layer, the third conductive layer and the fourth conductive layer can receive different voltage signals through different signal electrodes respectively. For example, the first conductive layer can receive the first voltage, and the second conductive layer can receive the second voltage. The third conductive layer can receive the third voltage, and the fourth conductive layer can receive the fourth voltage. The first voltage is different from the fourth voltage, and the second voltage is different from the third voltage. And when the first voltage is greater than the fourth voltage, a potential difference can be formed between the first conductive layer and the fourth conductive layer. When the third voltage is also greater than the second voltage, a potential difference can also be formed between the third conductive layer and the second conductive layer, thereby generating an electrostatic force between the first comb teeth and the second comb teeth, thereby driving the second comb teeth to rotate. Since the second comb teeth are fixed to the suspended portion of the support beam, the second comb teeth can drive the support beam to rotate, and thus, the MEMS chip of the present application can be applied to devices that require a rotating pair, for example, it can be applied to a MEMS galvanometer.

[0019] The MEMS chip may also include a ground electrode. In a possible embodiment, at least two conductive layers of the first comb teeth are connected to the ground electrode, and at least two conductive layers of the second comb teeth are connected to the same signal electrode, or at least two conductive layers of the second comb teeth are connected to different signal electrodes. In this way, each conductive layer of the first comb teeth can form a capacitor with each conductive layer of the second comb teeth. Exemplarily, a first capacitor can be formed between the first conductive layer and the third conductive layer, and a second capacitor can be formed between the second conductive layer and the fourth conductive layer. Since the number of the first comb teeth and the number of the second comb teeth are both multiple, the comb teeth can form multiple first capacitors and multiple second capacitors, multiple first capacitors are connected in series, and multiple second capacitors are connected in series. The MEMS chip can be a MEMS accelerometer. When the MEMS accelerometer is used to detect the object to be detected, the electronic device including the MEMS chip can be fixed on the object to be detected. When the object to be detected moves, the suspended portion of the support beam also moves, thereby driving the second comb teeth to move. When the object to be detected moves in different directions, the change amount and change trend of the first capacitor and the second capacitor corresponding to each comb tooth pair may be different. Therefore, the acceleration magnitude and direction of the object to be detected can be calculated by the change amount and change trend of the first capacitor and the second capacitor corresponding to each comb tooth pair. Moreover, the present application can detect acceleration in three directions by the change amount and change trend of the first capacitor and the second capacitor corresponding to each comb tooth pair, thereby improving the integration of the MEMS chip.

[0020] In a possible implementation, at least two conductive layers of the second comb teeth of each comb tooth pair are connected to the ground electrode, that is, the third conductive layer and the fourth conductive layer are connected to the ground electrode. The first conductive layers of the first comb teeth of two oppositely arranged comb tooth pairs are respectively connected to different signal electrodes, and the second conductive layers of the first comb teeth of two oppositely arranged comb tooth pairs are respectively connected to different signal electrodes.

[0021] The first conductive layer and the second conductive layer of the same comb tooth pair are connected to the same signal electrode, the first conductive layer and the second conductive layer of one of the two comb tooth pairs arranged opposite to each other can receive a first voltage, and the first conductive layer and the second conductive layer of the other comb tooth pair can receive a second voltage, and the first voltage and the second voltage are of the same magnitude and opposite in direction. A potential difference is formed between the first conductive layer and the third conductive layer, and a potential difference is formed between the second conductive layer and the fourth conductive layer, thereby driving the mass block to resonate under the action of electrostatic force. Therefore, the present application can realize the driving mode of the MEMS gyroscope.

[0022] Moreover, the two relative comb teeth can form a plurality of first capacitors, a plurality of second capacitors, a plurality of third capacitors and a plurality of fourth capacitors. When the second comb teeth rotate in two different directions, the capacitance changes of the plurality of first capacitors, the plurality of second capacitors, the plurality of third capacitors and the plurality of fourth capacitors are different, and thus the magnitude and direction of the angular velocity can be calculated by the capacitance changes of these capacitors. Therefore, the present application can detect the magnitude of the angular velocity of the object to be detected in two different directions, thereby improving the integration of the MEMS gyroscope.

[0023] In other embodiments, the first conductive layer and the second conductive layer of the same comb-tooth pair are connected to different signal electrodes.

[0024] In another possible implementation, the first conductive layers of the first comb teeth of two relatively arranged comb tooth pairs are connected to the ground electrode, and the second conductive layers of the first comb teeth of two relatively arranged comb tooth pairs are connected to the same signal electrode. The second conductive layer and the third conductive layer of the second comb teeth are respectively connected to different signal electrodes, and the fourth conductive layer of the second comb teeth of each comb tooth pair is connected to the ground electrode. The first conductive layer of the first comb teeth of two relatively arranged comb tooth pairs is grounded, and the third conductive layer of the second comb teeth is grounded. The second conductive layer of the two relatively arranged comb tooth pairs is used to receive a first voltage, and the fourth conductive layer of the second comb teeth is used to receive a second voltage, and the first voltage is the same as the second voltage in magnitude and opposite in direction. A potential difference can be formed between the first conductive layer and the third conductive layer, and a potential difference can be formed between the second conductive layer and the fourth conductive layer, thereby driving the second comb teeth to resonate under the action of electrostatic force. Therefore, the present application can realize the driving mode of MEMS.

[0025] Moreover, the two relative comb teeth can form a plurality of first capacitors, a plurality of second capacitors, a plurality of third capacitors and a plurality of fourth capacitors. When the second comb teeth rotate in two different directions, the capacitance changes of the plurality of first capacitors, the plurality of second capacitors, the plurality of third capacitors and the plurality of fourth capacitors are different, and thus the magnitude and direction of the angular velocity can be calculated by the capacitance changes of these capacitors. Therefore, the present application can detect the magnitude of the angular velocity of the object to be detected in three different directions, thereby improving the integration of the MEMS gyroscope.

[0026] The third aspect of the present application also provides a method for manufacturing a MEMS chip, the manufacturing method comprising: providing a substrate. Manufacturing at least two conductive layers on the substrate. Etching the at least two conductive layers to form a support beam and a comb tooth pair, wherein the support beam has a suspended portion; the comb tooth pair comprises a plurality of first comb teeth and a plurality of second comb teeth, the plurality of first comb teeth are arranged in a direction perpendicular to the thickness direction of the MEMS chip, the plurality of second comb teeth are arranged in a direction perpendicular to the thickness direction, the plurality of first comb teeth and the plurality of second comb teeth have the same arrangement direction and are arranged alternately; the first comb teeth comprise at least two conductive layers stacked in the thickness direction, the second comb teeth comprise at least one conductive layer, and the at least one conductive layer of the first comb teeth and the at least one conductive layer of the second comb teeth are arranged in the same layer;

[0027] The substrate is etched to form a base plate.

[0028] Since the first comb teeth include at least two conductive layers, when manufacturing the first comb teeth, the at least two conductive layers can be manufactured separately by a process of first deposition and then etching. At least one conductive layer of the second comb teeth is arranged on the same layer as at least one conductive layer of the first comb teeth. Therefore, when manufacturing the first comb teeth, the second comb teeth can be manufactured. In other words, the first comb teeth and the second comb teeth can be manufactured on the same process platform and in the same process, thereby reducing the complexity of the manufacturing process of the MEMS chip and also reducing the manufacturing cost.

[0029] In addition, when the MEMS chip is used, different voltage signals can be provided to at least two stacked conductive layers, so that the same MEMS chip can realize multiple different functions, such as driving and sensing, thereby improving the integration of the MEMS chip.

[0030] The third aspect of the present application provides an electronic device, comprising a circuit board and a MEMS chip of any implementation of the first aspect or a MEMS chip manufactured by any implementation of the second aspect, wherein the circuit board is electrically connected to the MEMS chip. The electronic device can achieve all the effects of the MEMS chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0032] Figure 1a This is a schematic diagram of the structure of an electronic device in an embodiment of the present application;

[0033] Figure 1b This is a schematic diagram of the structure of an electronic device in another embodiment of the present application;

[0034] Figure 2a It is a schematic diagram of the planar structure of a comb tooth pair in the related art;

[0035] Figure 2b It is a schematic diagram of the cross-sectional structure of a coplanar comb tooth pair in the related art;

[0036] Figure 2c It is a schematic diagram of the cross-sectional structure of a comb tooth pair in the related art that is a comb tooth pair with different surfaces;

[0037] Figure 3a This is a structural schematic diagram of a MEMS chip in an embodiment of the present application when it is a MEMS galvanometer;

[0038] Figure 3b for Figure 3a A cross-sectional view of the first comb tooth pair at AA;

[0039] Figure 4 for Figure 3a A schematic diagram of a first cross-sectional structure;

[0040] Figure 5 for Figure 3a A schematic diagram of a second cross-sectional structure;

[0041] Figure 6 for Figure 3a A schematic diagram of the third cross-sectional structure;

[0042] Figure 7 for Figure 3a A schematic diagram of a fourth cross-sectional structure;

[0043] Figure 8 for Figure 3a A schematic diagram of the fifth cross-sectional structure;

[0044] Fig. 9 This is a structural schematic diagram of the MEMS chip in the embodiment of the present application being a MEMS accelerometer;

[0045] Fig.10a for Fig. 9 The cross-sectional view at BB in FIG.

[0046] Fig.10b for Fig.10a A schematic diagram of the structure after the second comb teeth move upward;

[0047] Fig.11 for Fig.10a and Fig.10b Equivalent circuit diagram of the structure shown;

[0048] Fig.12 This is a structural schematic diagram of a MEMS chip in an embodiment of the present application when it is a MEMS gyroscope;

[0049] Fig.13 for Fig.12 A local enlarged schematic diagram in FIG.

[0050] Fig.14 for Fig.13 The cross-sectional view at DD in ;

[0051] Fig.15 This is a structural schematic diagram of a MEMS chip in an embodiment of the present application when it is a MEMS gyroscope;

[0052] Fig.16a for Fig.13 The cross-sectional view of the MEMS chip at EE in the first sensing mode;

[0053] Fig.16b for Fig.13 The cross-sectional view of the MEMS chip at EE in the second sensing mode;

[0054] Fig.17 for Fig.16a and Fig.16b Equivalent circuit diagram of the structure shown;

[0055] Fig.18 for Fig.15 Cross-sectional view at FF;

[0056] Fig.19 A schematic diagram of a process for manufacturing a MEMS chip according to an embodiment of the present application;

[0057] Fig. 20 for Fig.19 The specific manufacturing schematic diagram of S71-S75 in the manufacturing method shown;

[0058] Fig.21 for Fig.19 The specific manufacturing schematic diagram of S76 and S77 in the manufacturing method shown.

[0059] Icons: 10-MEMS chip; 20-circuit; 21-controller; 22-power supply; 23-voltage adjustment circuit; 24-detection circuit; 25-processor; 30-comb teeth pair; 301-first comb teeth pair; 302-second comb teeth pair; 303-third comb teeth pair; 304-fourth comb teeth pair; 31-first comb teeth; 311-conductive layer; 3111-first conductive layer; 3112-second conductive layer; 3113-third conductive layer; 3114-fourth conductive layer Electrical layer; 312-interlayer insulating layer; 313-upper insulating layer; 314-lower insulating layer; 32-second comb teeth; 40-base plate; 41-hollow area; 42-support frame; 43-fixed part; 44-anchor point; 51-substrate; 52-first insulating layer; 53-first conductive layer; 54-second insulating layer; 55-second conductive layer; 56-third insulating layer; 61-support beam; 611-fixed end; 612-suspended part; 62-lens; 63-mass block. DETAILED DESCRIPTION

[0060] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0061] The term "and / or" herein is merely a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone, wherein A and B may be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one (item)" refers to one or more, and "more" refers to two or more. "At least one of the following (items)" or similar expressions refers to any combination of these items, including any combination of single (items) or plural (items). For example, at least one (item) of a, b or c may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or multiple.

[0062] The terms "first" and "second" in the description and claims of the embodiments of the present application are used to distinguish different objects rather than to describe a specific order of objects. For example, a first target object and a second target object are used to distinguish different target objects rather than to describe a specific order of target objects.

[0063] "Connected", "connected" and similar words are used to express the intercommunication or interaction between different components, which may include direct connection or indirect connection through other components. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, inclusion of a series of steps or units. Methods, systems, products or devices are not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. "Up", "down", "left", "right" and the like are only used relative to the orientation of the components in the drawings. These directional terms are relative concepts. They are used for description and clarification relative to the description, which may change accordingly according to the change of the orientation of the components in the drawings.

[0064] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0065] In the description of the embodiments of the present application, unless otherwise specified, the meaning of "multiple" refers to two or more than two. For example, multiple processing units refer to two or more processing units; multiple systems refer to two or more systems.

[0066] Electronic devices such as mobile phones, electronic watches, televisions, etc., may generally include a MEMS chip, a circuit board electrically connected to the MEMS chip, and a circuit electrically connected to the MEMS chip. The MEMS chip may be a MEMS driver, such as a MEMS resonator, a MEMS micro-mirror, a MEMS optical image stabilization device, a MEMS speaker, or a MEMS switch, etc. The MEMS chip may also be a MEMS sensor, such as a MEMS crystal oscillator, a MEMS accelerometer, a MEMS gyroscope, or a MEMS clock device, etc.

[0067] When the MEMS chip is a MEMS driver, such as Figure 1a As shown, the circuit 20 in the electronic device may include a controller 21, a power supply 22, and a voltage adjustment circuit 23. The power supply 22 may be electrically connected to the voltage adjustment circuit 23. The controller 21 may be electrically connected to the voltage adjustment circuit 23. The voltage adjustment circuit 23 may be electrically connected to the MEMS chip 10, so that the power supply 22 may send a voltage signal to the MEMS chip 10 through the voltage adjustment circuit 23, and the controller 21 may control the voltage magnitude and phase of the voltage signal sent by the voltage adjustment circuit 23 to the MEMS chip 10, so as to realize the driving function of the MEMS driver.

[0068] When the MEMS chip 10 is a MEMS sensor, Figure 1b As shown, the circuit 20 in the electronic device may include a detection circuit 24 and a processor 25 in addition to the controller 21, the power supply 22 and the voltage adjustment circuit 23. The detection circuit 24 may be electrically connected to the processor 25, and the detection circuit 24 may also be electrically connected to the MEMS chip 10, so that the detection circuit 24 may detect the capacitance signal in the MEMS chip 10 and send it to the processor 25, and the processor 25 may calculate parameters such as acceleration and angular velocity according to the capacitance signal.

[0069] The MEMS chip 10 includes Figure 2a The comb teeth pair 30 shown. The comb teeth pair 30 includes a plurality of first comb teeth 31 and a plurality of second comb teeth 32, wherein the first comb teeth 31 may be driving comb teeth and the second comb teeth 32 may be driven comb teeth. Different voltage signals may be provided to the first comb teeth 31 and the second comb teeth 32 so that a potential difference is formed between the first comb teeth 31 and the second comb teeth 32, thereby generating an electrostatic force to drive the second comb teeth 32 to generate displacement. Moreover, a capacitor may be formed between the first comb teeth 31 and the second comb teeth 32. As the displacement of the second comb teeth 32 changes, the gap or overlapping area of ​​the capacitor formed between the first comb teeth 31 and the second comb teeth 32 will change, and the capacitance of the capacitor will also change accordingly, thereby calculating parameters such as acceleration and angular velocity based on the capacitance change of the capacitor, so as to realize the electrostatic induction of the MEMS sensor.

[0070] According to whether the driving comb teeth and the driven comb teeth are in the same plane, the comb teeth pair 30 can be divided into a coplanar comb teeth pair and a non-planar comb teeth pair. Figure 2b As shown, the coplanar comb teeth pair means that the first comb teeth 31 and the second comb teeth 32 are arranged on the same surface, that is, arranged in the same layer. Figure 2c As shown, the skew comb teeth pair means that the first comb teeth 31 and the second comb teeth 32 are arranged on different surfaces, that is, the first comb teeth 31 and the second comb teeth 32 are arranged on different layers. The coplanar comb teeth pair can be applied to the drive and feedback of in-plane motion. For example, when the first comb teeth 31 and the second comb teeth 32 need to produce a displacement away from or close to each other, the comb teeth pair 30 can adopt a coplanar comb teeth pair. The skew comb teeth pair can be applied to the drive and feedback of out-of-plane motion. For example, when the first comb teeth 31 and the second comb teeth 32 need to produce relative rotation, the comb teeth pair 30 can adopt a skew comb teeth pair. Of course, the coplanar comb teeth pair can also be applied to the drive and feedback of out-of-plane motion.

[0071] In related technologies, such as Figure 2b and 2cAs shown, the first comb teeth 31 and the second comb teeth 32 each include a conductive layer 311. For the MEMS chip 10 using the coplanar comb teeth pair, it can be manufactured on the same process platform. For the MEMS chip 10 using the skew comb teeth pair, since the first comb teeth 31 and the second comb teeth 32 are alternated along their arrangement direction and staggered along the thickness direction, that is, Figure 2a As shown, the first comb teeth 31 and the second comb teeth 32 are alternated along the Y direction and are misaligned along the Z direction. Therefore, when manufacturing the MEMS chip 10, it is necessary to manufacture the first comb teeth 31 on the first substrate, manufacture the second comb teeth 32 on the second substrate, then fix the second comb teeth 32 and the second substrate to the first comb teeth 31 and the first substrate by bonding, and etch away the second substrate to obtain the MEMS chip 10.

[0072] It can be seen that in the related art, the MEMS chip 10 using the coplanar comb teeth pair and the MEMS chip 10 using the skew comb teeth pair have different manufacturing processes and cannot be manufactured on the same process platform.

[0073] Based on this, an embodiment of the present application provides a MEMS chip 10, and a MEMS chip 10 using a coplanar comb tooth pair and a MEMS chip 10 using a skew comb tooth pair can be manufactured on the same process platform.

[0074] For the convenience of description, three directions may be defined, namely a first direction (X direction), a second direction (Y direction) and a third direction (Z direction), wherein the X direction represents the length direction of the MEMS chip 10, the Y direction represents the width direction of the MEMS chip 10, and the Z direction represents the thickness direction of the MEMS chip 10. The X direction, the Y direction and the Z direction are perpendicular to each other.

[0075] like Figure 3a As shown, the MEMS chip 10 of this embodiment may be a MEMS galvanometer. The MEMS chip 10 may include: a substrate 40 , a support beam 61 , a lens 62 and a comb tooth pair 30 .

[0076] like Figure 3a As shown, the substrate 40 may include a support frame 42 and a fixing portion 43. The support frame 42 may be a frame-type structure. The support frame 42 may form a hollow area 41 in the middle thereof.

[0077] like Figure 3a As shown, the support beam 61 includes two fixed ends 611 and a suspended portion 612 between the two fixed ends 611. The two fixed ends 611 are respectively connected to the substrate 40 in a rotatable manner, and the suspended portion 612 is suspended above the hollow area 41 of the substrate 40. The support beam 61 rotates around its own axis when subjected to external force.

[0078] like Figure 3aAs shown, the lens 62 is fixed on the support beam 61. In this way, when the support beam 61 rotates around its own axis, it will drive the lens 62 to rotate together, thereby adjusting the incident angle of the light received by the lens 62.

[0079] like Figure 3a As shown, in this embodiment, the number of the fixing parts 43 can be two. Both fixing parts 43 are fixed on the substrate 40. Moreover, the two fixing parts 43 are respectively arranged on two opposite sides of the support beam 61. When the MEMS galvanometer is used, the fixing part 43 always keeps a fixed position.

[0080] like Figure 3a As shown, the number of comb tooth pairs 30 can be two, and the two comb tooth pairs 30 are respectively fixed between the two fixing portions 43 and the support beam 61. Each comb tooth pair 30 can include a plurality of first comb teeth 31 and a plurality of second comb teeth 32. The plurality of first comb teeth 31 are fixed on the fixing portion 43, and are arranged along the Y direction and extend along the X direction. There is a gap between each two adjacent first comb teeth 31.

[0081] like Figure 3b As shown, the first comb tooth 31 includes at least two conductive layers 311 stacked along the Z direction, an interlayer insulating layer 312 located between two adjacent conductive layers 311, an upper insulating layer 313 located above the at least two conductive layers 311, and a lower insulating layer 314 located below the at least two conductive layers 311.

[0082] It can be understood that “above” and “below” are both directions determined by taking the substrate 40 as the bottom of the MEMS chip 10 .

[0083] like Figure 3a As shown, the plurality of second comb teeth 32 are fixed on the suspended portion 612, and are arranged along the Y direction and extend along the X direction. There is a gap between each two adjacent second comb teeth 32. It is understandable that in other embodiments, the plurality of first comb teeth 31 can be fixed on the suspended portion 612, and the plurality of second comb teeth 32 can be fixed on the substrate 40.

[0084] like Figure 3b As shown, the second comb teeth 32 include at least two conductive layers 311 stacked along the Z direction, an interlayer insulating layer 312 located between two adjacent conductive layers 311, an upper insulating layer 313 located above the at least two conductive layers 311, and a lower insulating layer 314 located below the at least two conductive layers 311.

[0085] The plurality of first comb teeth 31 and the plurality of second comb teeth 32 are arranged in the same direction and are arranged alternately. Figure 3aAs shown, the plurality of first comb teeth 31 and the plurality of second comb teeth 32 are arranged along the Y direction. Moreover, a second comb tooth 32 is disposed before each two adjacent first comb teeth 31 , and a first comb tooth 31 is disposed between each two adjacent second comb teeth 32 .

[0086] At least one conductive layer 311 of the first comb teeth 31 is disposed on the same layer as at least one conductive layer 311 of the second comb teeth 32. In a possible implementation manner, Figure 3b As shown, the comb teeth pair 30 is a coplanar comb teeth pair. In another possible embodiment, as Figure 7 As shown, the comb teeth pair 30 is a skew-coplanar comb teeth pair.

[0087] like Figure 3b As shown, when the comb tooth pair 30 is a coplanar comb tooth pair, the first comb tooth 31 and the second comb tooth 32 both include at least two conductive layers 311, and the number of the conductive layers 311 of the first comb tooth 31 is the same as the number of the conductive layers 311 of the second comb tooth 32. The at least two conductive layers 311 of the first comb tooth 31 and the at least two conductive layers 311 of the second comb tooth 32 are respectively and correspondingly arranged in the same layer. The thickness of the at least two conductive layers 311 of the first comb tooth 31 and the at least two conductive layers 311 of the second comb tooth 32 are respectively and correspondingly the same.

[0088] For example, in this embodiment, Figure 3b As shown, the first comb teeth 31 include two conductive layers 311, which are the first conductive layer 3111 and the second conductive layer 3112 from top to bottom. The second comb teeth 32 include two conductive layers 311, which are the third conductive layer 3113 and the fourth conductive layer 3114 from top to bottom. The first conductive layer 3111 and the third conductive layer 3113 are arranged in the same layer, and the second conductive layer 3112 and the fourth conductive layer 3114 are arranged in the same layer. The thickness of the first conductive layer 3111 is the same as that of the third conductive layer 3113, and the thickness of the second conductive layer 3112 is the same as that of the fourth conductive layer 3114. In this way, when manufacturing the comb tooth pair 30, at least two polysilicon layers, an insulating layer located between two adjacent polysilicon layers, and insulating layers located above and below the two polysilicon layers can be respectively manufactured by deposition, and then the two polysilicon layers and the three insulating layers are etched by etching to form the first comb teeth 31 and the second comb teeth 32. Therefore, the first comb teeth 31 and the second comb teeth 32 can be manufactured on the same process platform, and the first comb teeth 31 and the second comb teeth 32 can be manufactured at the same time.

[0089] Moreover, in the related art, the first comb teeth 31 and the second comb teeth 32 are made separately, and then the MEMS chip 10 is made by bonding. In view of the large processing error of the bonding process, the matching accuracy between the first comb teeth 31 and the second comb teeth 32 of the MEMS chip 10 in the related art is poor, and the yield is low. In the present embodiment, the first comb teeth 31 and the second comb teeth 32 can be made on the same process platform, and the first comb teeth 31 and the second comb teeth 32 can be made at the same time, thereby improving the manufacturing accuracy and further improving the yield. For example, the gap between the first comb teeth 31 and the second comb teeth 32 can be less than 1 μm, so that after the voltage signal is provided to the first comb teeth 31 and the second comb teeth 32 respectively, the electrostatic force generated between the first comb teeth 31 and the second comb teeth 32 can be increased.

[0090] The first conductive layer 3111 and the second conductive layer 3112 are provided with conductive bodies ( Figure 3b The MEMS galvanometer may also include a plurality of signal electrodes ( Figure 3b The first conductive layer 3111 and the second conductive layer 3112 are connected to different signal electrodes through respective conductors. The signal electrodes may be connected to Figure 2b The circuit 20 shown in the figure is connected, and the circuit 20 can send a voltage signal to the signal electrode. As a result, the first conductive layer 3111 and the second conductive layer 3112 can receive the voltage signal through the signal electrode. For example, in this embodiment, the first conductive layer 3111 of the first comb tooth 31 can receive the first voltage signal, and the second conductive layer 3112 can receive the second voltage signal.

[0091] Conductors are respectively provided on the third conductive layer 3113 and the fourth conductive layer 3114 of the second comb teeth 32, and the third conductive layer 3113 and the second and fourth conductive layers are respectively connected to different signal electrodes through their respective conductors. Thus, voltage signals can be received through the signal electrodes. For example, the third conductive layer 3113 can receive a third voltage signal, and the fourth conductive layer 3114 can receive a fourth voltage signal.

[0092] Figure 3bThe first voltage V1 in the first voltage signal is different from the fourth voltage V4 in the fourth voltage signal, and the second voltage V2 in the second voltage signal is different from the third voltage V3 in the third voltage signal. In this way, the first conductive layer 3111 and the second conductive layer 3112, the third conductive layer 3113 and the fourth conductive layer 3114 can respectively receive different voltage signals through different signal electrodes, and the second conductive layer 3112 and the third conductive layer 3113 can also respectively receive different voltage signals through different signal electrodes. And when the first voltage V1 is greater than the fourth voltage V4, a potential difference can be formed between the first conductive layer 3111 and the fourth conductive layer 3114. When the third voltage V3 is also greater than the second voltage V2, a potential difference can also be formed between the third conductive layer 3113 and the second conductive layer 3112, thereby generating an electrostatic force between the first comb teeth 31 and the second comb teeth 32, thereby driving the second comb teeth 32 to rotate. As Figure 3a As shown, since the second comb teeth 32 are fixed to the suspended portion 612 of the support beam 61 , the second comb teeth 32 can drive the support beam 61 to rotate clockwise and counterclockwise, thereby driving the lens 62 fixed on the support beam 61 to rotate. Figure 2b The voltage signal sent by the circuit 20 shown can be an AC voltage signal, so that as the voltage signal changes, the support beam 61 can realize counterclockwise and clockwise rotation. Therefore, different voltage signals can be provided to at least two stacked conductive layers 311 to realize relative rotation between the first comb tooth 31 and the second comb tooth 32, thereby realizing out-of-plane motion driving.

[0093] Regarding the relationship between the thickness of the first conductive layer 3111 and the second conductive layer 3112, in one example, Figure 4 As shown, the thickness of the first conductive layer 3111 is the same as the thickness of the second conductive layer 3112. In this way, the structural parameters of the first conductive layer 3111 and the second conductive layer 3112 are completely the same, and the structure is suitable for the MEMS chip 10 in which the lower insulating layer 314, the second conductive layer 3112, the interlayer insulating layer 312, the first conductive layer 3111 and the upper insulating layer 313 are in a vertically symmetrical structure. In another example, as Figure 5 As shown, the thickness of the first conductive layer 3111 is different from the thickness of the second conductive layer 3112. Exemplarily, the thickness of the first conductive layer 3111 is greater than the thickness of the second conductive layer 3112, and correspondingly, the thickness of the third conductive layer 3113 is greater than the thickness of the fourth conductive layer 3114.

[0094] In other embodiments, Figure 6 As shown, the first comb teeth 31 and the second comb teeth 32 each include three conductive layers 311, and each conductive layer 311 of the first comb teeth 31 is disposed on the same layer and has the same thickness as each conductive layer 311 of the second comb teeth 32. In this way, different voltages can be configured for each conductive layer 311.

[0095] When the comb teeth pair 30 is a skew comb teeth pair, illustratively, the first comb teeth 31 include at least two conductive layers 311, and the second comb teeth 32 include one conductive layer 311. In one example, Figure 7 As shown, the first comb teeth 31 include a first conductive layer 3111 and a second conductive layer 3112, and the conductive layer 311 of the second comb teeth 32 is disposed on the same layer as the first conductive layer 3111. Figure 8 As shown, the conductive layer 311 of the second comb teeth 32 is arranged in the same layer as the second conductive layer 3112. In this way, when manufacturing the comb tooth pair 30, at least two layers of polysilicon layers, an insulating layer located between two adjacent polysilicon layers, and an insulating layer located above and below the two polysilicon layers can be respectively manufactured by deposition, and then the two polysilicon layers and the three insulating layers are etched by etching to form the first comb teeth 31 and the second comb teeth 32. Therefore, the first comb teeth 31 and the second comb teeth 32 can be manufactured on the same process platform, and the first comb teeth 31 and the second comb teeth 32 can be manufactured at the same time. Therefore, when the comb tooth pair 30 is a coplanar comb tooth pair or an eccentric comb tooth pair, the comb tooth pair 30 can be manufactured by deposition and etching, so that the MEMS chip 10 using the coplanar comb tooth pair and the MEMS chip 10 using the eccentric comb tooth pair are manufactured based on the same process platform.

[0096] It can be understood that, in this embodiment, Figure 3a As shown, the structures of the two comb tooth pairs 30 in the MEMS galvanometer are the same, and both comb tooth pairs 30 are coplanar comb tooth pairs. In other embodiments, both comb tooth pairs 30 can be skew comb tooth pairs. Alternatively, the structures of the two comb tooth pairs 30 in the MEMS galvanometer can be different. Exemplarily, one of the comb tooth pairs 30 is a coplanar comb tooth pair, and the other comb tooth pair 30 is a skew comb tooth pair.

[0097] In other embodiments of the present application, Fig. 9 As shown, the MEMS chip 10 may be a MEMS accelerometer. Fig. 9 As shown, the MEMS chip 10 may include a substrate 40, a mass block 63, a support beam 61, a comb tooth pair 30, a ground electrode ( Fig. 9 ) and a plurality of signal electrodes ( Fig. 9(not shown in the figure). The substrate 40 includes a fixing portion 43 and an anchor point 44. The number of the fixing portions 43 may be four, the number of the support beams 61 may be four, and the number of the comb tooth pairs 30 may also be four. The number of the mass block 63 may be one, and the number of the anchor points 44 may be four. The four fixing portions 43 are arranged on the periphery of the mass block 63 in a rectangular array. Each comb tooth pair 30 is connected between each fixing portion 43 and the mass block 63. The four anchor points 44 are arranged on the periphery of the mass block 63 in a rectangular array and are located at the four corners of the mass block 63. A support beam 61 is connected between each anchor point 44 and the plurality of second comb teeth 32 of each comb tooth pair 30, and the support beam 61 is in a rectangular wave shape. The support beam 61 has a certain flexibility, and the mass block 63 is fixed to the suspended portion 612 of the support beam 61. When the mass block 63 is subjected to force, the mass block 63 is displaced, driving the support beam 61 to produce a certain deformation.

[0098] For ease of description, Fig. 9 As shown, the four comb tooth pairs 30 can be respectively named as the first comb tooth pair 301, the second comb tooth pair 302, the third comb tooth pair 303 and the fourth comb tooth pair 304. The first comb tooth pair 301 and the third comb tooth pair 303 are arranged opposite to each other, and the second comb tooth pair 302 and the fourth comb tooth pair 304 are arranged opposite to each other. The first comb teeth 31 and the second comb teeth 32 in the first comb tooth pair 301 and the third comb tooth pair 303 are arranged along the Y direction, and the first comb teeth 31 and the second comb teeth 32 in the second comb tooth pair 302 and the fourth comb tooth pair 304 are arranged along the X direction.

[0099] like Fig.10a As shown, at least two conductive layers 311 of the first comb teeth 31 are connected to the ground electrode. In this embodiment, at least two conductive layers 311 of the second comb teeth 32 are connected to the same signal electrode, so that at least two conductive layers 311 of the second comb teeth 32 can receive the same voltage signal. Figure 2b In the circuit 20 shown, a voltage adjustment circuit 23 may be provided for at least two conductive layers 311 to output a voltage signal. In other embodiments, at least two conductive layers 311 of the second comb teeth 32 are respectively connected to different signal electrodes. In this way, at least two conductive layers 311 of the second comb teeth 32 may receive different voltage signals respectively. Therefore, a plurality of different voltage adjustment circuits 23 may be provided for at least two conductive layers 311 in the circuit 20, and the plurality of voltage adjustment circuits 23 are respectively electrically connected to at least two conductive layers 311 of the second comb teeth 32.

[0100] like Fig.10a As shown, since the first conductive layer 3111 of the first comb tooth 31 is connected to the ground electrode, the third conductive layer 3113 of the second comb tooth 32 is connected to the signal electrode, and when the third conductive layer 3113 receives a voltage signal, the first conductive layer 3111 and the third conductive layer 3113 can form Fig.11 The second conductive layer 3112 is connected to the ground electrode, and the fourth conductive layer 3114 of the second comb 32 is connected to the signal electrode. When the fourth conductive layer 3114 receives a voltage signal, the second conductive layer 3112 and the fourth conductive layer 3114 can form a Fig.11 Since the number of the first comb teeth 31 and the number of the second comb teeth 32 are both multiple, the comb tooth pair 30 can form multiple first capacitors C1 and multiple second capacitors C2, and the multiple first capacitors C1 are connected in series, and the multiple second capacitors C2 are connected in series. Each comb tooth pair 30 corresponds to multiple first capacitors and multiple second capacitors, Figure 1b The detection circuit 24 shown can detect the capacitance signal of each capacitor, that is, in this embodiment, the capacitance signal of the first capacitor C1 of the four comb tooth pairs 30 and the capacitance signal of the second capacitor C2 of the four comb tooth pairs 30 can be detected, so as to calculate the acceleration of the object to be detected based on the capacitance signal.

[0101] In the application of MEMS accelerometer, the MEMS accelerometer is fixed on the object to be detected, or the electronic device containing the MEMS accelerometer is fixed on the object to be detected. Fig. 9 The mass block 63 in the support beam 61 also moves, and the suspended portion 612 of the support beam 61 also moves, thereby driving the second comb teeth 32 to move.

[0102] For example, when the object to be detected moves along the X direction, since the mass block 63 is arranged on the suspended portion 612 of the support beam 61, the mass block 63 also moves along the X direction. The second comb teeth 32 in the four comb tooth pairs 30 all move along the X direction. In this way, the overlapping area between the first comb teeth 31 and the second comb teeth 32 of the first comb tooth pair 301 and the overlapping area between the first comb teeth 31 and the second comb teeth 32 of the third comb tooth pair 303 both change, so the overlapping area of ​​the first capacitor C1 and the second capacitor C2 formed by the first comb tooth pair 301 and the third comb tooth pair 303 changes, so the capacitance of the first capacitor C1 and the second capacitor C2 formed by the first comb tooth pair 301 and the second comb tooth pair 302 both changes, and the change amount is large and changes linearly. For the second comb tooth pair 302 and the fourth comb tooth pair 304, the movement of the second comb tooth 32 along the X direction will cause the gap between the first comb tooth 31 and the second comb tooth 32 to change, thereby the first capacitor C1 and the second capacitor C2 formed by the second comb tooth pair 302 and the fourth comb tooth pair 304 also change, but the change is small and presents a nonlinear change.

[0103] When the object to be detected moves along the Y direction, the mass block 63 also moves along the Y direction. In contrast to the case where the object to be detected moves along the X direction, the capacitance changes of the first capacitor C1 and the second capacitor C2 corresponding to the first comb tooth pair 301 and the third comb tooth pair 303 are small and change nonlinearly; the capacitance changes of the first capacitor C1 and the second capacitor C2 corresponding to the second comb tooth pair 302 and the fourth comb tooth pair 304 are large and change linearly.

[0104] Moreover, when the object to be detected moves along the X direction and / or the Y direction, the capacitance changes of the first capacitor C1 and the second capacitor C2 are the same.

[0105] When the object to be detected moves along the Z direction, the mass block 63 also moves along the Z direction. For example, when the object to be detected moves upward, Fig.10b As shown, the second comb teeth 32 move upwards. Since the overlapping area between the first conductive layer 3111 and the third conductive layer 3113 changes greatly, Fig.11 The capacitance change of the first capacitor C1 shown is relatively large. Since the second conductive layer 3112 overlaps with part of the third conductive layer 3113 and part of the fourth conductive layer 3114, and the second conductive layer 3112 also overlaps with the insulating layer between the third conductive layer 3113 and the fourth conductive layer 3114, the influence of the overlapping area on the second capacitor C2C1 is relatively small and can be ignored. Therefore, the capacitance change of the second capacitor C2 is relatively small. When the object to be detected moves downward, the capacitance change of the first capacitor C1 and the second capacitor C2 is opposite to that when the object to be detected moves upward, that is, the capacitance change of the first capacitor C1 is relatively small, and the capacitance change of the second capacitor C2 is relatively large.

[0106] It can be seen that when the object to be detected moves along the Z direction, the capacitance changes of the first capacitor C1 and the second capacitor C2 are different. However, the capacitance changes of the first capacitor C1 and the second capacitor C2 corresponding to each comb tooth pair 30 are the same.

[0107] Therefore, after obtaining the capacitance signal of the first capacitor C1 and the capacitance signal of the second capacitor C2 corresponding to each comb tooth pair 30, if the capacitance change of the first capacitor C1 corresponding to each comb tooth pair 30 is the same, and the capacitance change of the second capacitor C2 corresponding to each comb tooth pair 30 is the same, it indicates that the acceleration of the object to be detected is in the Z direction. And further, according to the magnitude relationship between the capacitance change of the first capacitor C1 and the capacitance change of the second capacitor C2, it is determined whether the direction of the acceleration is upward or downward, and the magnitude of the acceleration is calculated according to the capacitance change of the first capacitor C1 and the capacitance change of the second capacitor C2. If the capacitance change of the first capacitor C1 corresponding to some of the four comb tooth pairs 30 is different, and the capacitance change of the first capacitor C1 corresponding to some of the comb tooth pairs 30 is different, it indicates that the acceleration direction of the object to be detected is in the X direction or the Y direction. Then, the direction of the acceleration of the object to be detected can be determined according to the capacitance change of the first capacitor C1 and the second capacitor C2 corresponding to different comb teeth pairs 30 and whether it is a linear change, and the magnitude of the acceleration can be calculated according to the capacitance change of the first capacitor C1 and the second capacitor C2. Therefore, in this embodiment, the MEMS accelerometer can detect the acceleration of the object to be detected along the X direction, along the Y direction, and along the Z direction at the same time. Figure 2b In the related art shown, the first comb teeth 31 and the second comb teeth 32 both include a conductive layer 311 , so they can only detect acceleration in two directions. Therefore, the embodiment of the present application can improve the integration of the MEMS accelerometer.

[0108] In other embodiments of the present application, the MEMS chip 10 may be a MEMS gyroscope. Fig.12 As shown, Fig. 9 The difference between the illustrated embodiments lies in the number of anchor points 44 and the structure of the support beam 61. In the present embodiment, the number of anchor points 44 is two.

[0109] like Fig.13 As shown, the operating modes of the MEMS gyroscope may include a first sensing mode, a second sensing mode, and a driving mode. With respect to the directions of the modes of the MEMS gyroscope, in a possible implementation, as Fig.13 As shown, the direction of the driving mode is the X direction, the direction of the first sensing mode is the Y direction, and the direction of the second sensing mode is the Z direction.

[0110] At least two conductive layers 311 of the second comb teeth 32 of the first comb tooth pair 301 and the third comb tooth pair 303 are connected to the ground electrode, that is, Fig.14The third conductive layer 3113 and the fourth conductive layer 3114 are both connected to the ground electrode. The first conductive layers 3111 of the first comb tooth pair 301 and the third comb tooth pair 303 are respectively connected to different signal electrodes, and the second conductive layers 3112 of the first comb tooth pair 301 and the third comb tooth pair 303 are respectively connected to different signal electrodes. Fig.14 As shown, the first conductive layer 3111 of the first comb tooth pair 301 and the first conductive layer 3111 of the third comb tooth pair 303 are connected to different signal electrodes, so that the first conductive layer 3111 of the first comb tooth pair 301 and the first conductive layer 3111 of the third comb tooth pair 303 can receive different voltage signals.

[0111] The first conductive layer 3111 and the second conductive layer 3112 of the first comb tooth pair 301 can be connected to the same signal electrode, that is, the first conductive layer 3111 and the second conductive layer 3112 of the first comb tooth pair 301 can receive the first voltage signal through the signal electrode. The first conductive layer 3111 and the second conductive layer 3112 of the third comb tooth pair 303 can be connected to the same signal electrode, that is, the first conductive layer 3111 and the second conductive layer 3112 of the third comb tooth pair 303 can receive the second voltage signal through the signal electrode, and the first voltage signal and the second voltage signal are a pair of differential signals, that is, the first voltage V1 in the first voltage signal and the second voltage V2 in the second voltage signal are the same in magnitude and opposite in direction. In this way, Fig.14 As shown, a first voltage V1 is applied to both the first conductive layer 3111 and the second conductive layer 3112 of the first comb-tooth pair 301 , and a second voltage V2 is applied to both the first conductive layer 3111 and the second conductive layer 3112 of the third comb-tooth pair 303 .

[0112] Therefore, if Fig.14 As shown, a potential difference is formed between the first conductive layer 3111 and the third conductive layer 3113 of the first comb tooth pair 301, and a potential difference is formed between the third conductive layer 3113 and the first conductive layer 3111 of the third comb tooth pair 303. Moreover, a potential difference is formed between the second conductive layer 3112 and the fourth conductive layer 3114 of the first comb tooth pair 301, and a potential difference is formed between the fourth conductive layer 3114 and the second conductive layer 3112 of the third comb tooth pair 303. An electrostatic force is generated between the first comb tooth 31 and the second comb tooth 32 of the first comb tooth pair 301, and an electrostatic force is generated between the first comb tooth 31 and the second comb tooth 32 of the third comb tooth pair 303, thereby driving the mass block 63 to generate resonance, thereby realizing the driving mode.

[0113] In the first sensing mode and the second sensing mode, Fig.16aThe third conductive layer 3113 and the fourth conductive layer 3114 of the second comb teeth 32 of the second comb tooth pair 302 and the fourth comb tooth pair 304 are both connected to the ground electrode, the first conductive layer 3111 of the second comb tooth pair 302 and the fourth comb tooth pair 304 are respectively connected to different signal electrodes, the second conductive layer 3112 of the second comb tooth pair 302 and the fourth comb tooth pair 304 are respectively connected to different signal electrodes, the first conductive layer 3111 and the second conductive layer 3112 of the second comb tooth pair 302 are connected to the same signal electrode, and the first conductive layer 3111 and the second conductive layer 3112 of the fourth comb tooth pair 304 are connected to the same signal electrode. In this way, the third conductive layer 3113 and the fourth conductive layer 3114 of the second comb tooth pair 302 and the fourth comb tooth pair 304 are both grounded. The first conductive layer 3111 and the second conductive layer 3112 of the second comb tooth pair 302 can receive the first voltage V1, and the first conductive layer 3111 and the second conductive layer 3112 of the fourth comb tooth pair 304 can receive the second voltage V2. The first voltage V1 and the second voltage V2 are of the same magnitude and opposite in direction.

[0114] The first conductive layer 3111 and the third conductive layer 3113 of the second comb tooth pair 302 form Fig.17 The first capacitor C1 shown in the figure, the second conductive layer 3112 of the second comb tooth pair 302 and the fourth conductive layer 3114 form Fig.17 The second capacitor C2 shown in FIG. 1 is formed by the third conductive layer 3113 of the fourth comb tooth pair 304 and the first semiconductor Fig.17 The third capacitor C3 shown in the figure, the fourth conductive layer 3114 of the fourth comb tooth pair 304 and the second semiconductor form Fig.17 The fourth capacitor C4 is shown.

[0115] In the first sensing mode, when the object to be detected rotates around the axis along the X direction, the mass block 63 also rotates around the axis along the X direction, and the Coriolis force is along the Y direction. Exemplarily, when the object to be detected rotates clockwise around the axis along the X direction, the overlapping area of ​​the first capacitor C1 and the fourth capacitor C4 remains substantially unchanged, and therefore, the capacitance change of the first capacitor C1 and the fourth capacitor C4 remains substantially unchanged. The overlapping area of ​​the second capacitor C2 and the third capacitor C3 decreases, and therefore, the capacitance of the second capacitor C2 and the third capacitor C3 decreases, and the capacitance change is large. When the object to be detected rotates counterclockwise around the axis along the X direction, the overlapping area of ​​the second capacitor C2 and the third capacitor C3 remains substantially unchanged, and therefore, the capacitance change of the second capacitor C2 and the third capacitor C3 remains substantially unchanged. The overlapping area of ​​the first capacitor C1 and the fourth capacitor C4 decreases, and therefore, the capacitance of the first capacitor C1 and the fourth capacitor C4 decreases, and the capacitance change is large.

[0116] In the second sensing mode, when the object to be detected rotates around the axis along the Y direction, the mass block 63 also rotates around the axis along the Y direction, and the Coriolis force is along the Z direction. Fig.16b As shown, the capacitance of the first capacitor C1 of some of the second comb tooth pairs 302 decreases, while the capacitance of the first capacitor C1 of some of the second comb tooth pairs 302 increases; the capacitance of the second capacitor C2 of some of the second comb tooth pairs 302 decreases, while the capacitance of the second capacitor C1 of some of the second comb tooth pairs 302 increases. Similarly, the capacitance of the third capacitor C3 of some of the fourth comb tooth pairs 304 decreases, while the capacitance of the third capacitor C3 of some of the fourth comb tooth pairs 304 increases; the capacitance of the second capacitor C2 of some of the fourth comb tooth pairs 304 decreases, while the capacitance of the second capacitor C2 of some of the fourth comb tooth pairs 304 increases.

[0117] It can be seen that when the object to be detected rotates along the axis of the X direction and around the axis of the Y direction, the capacitance changes of the first capacitor C1, the second capacitor C2, the third capacitor C3 and the fourth capacitor C4 corresponding to each comb tooth pair 30 are different. Therefore, the direction of the angular velocity of the object to be detected and the magnitude of the angular velocity can be determined according to the capacitance changes of the first capacitor C1, the second capacitor C2, the third capacitor C3 and the fourth capacitor C4 of each comb tooth pair 30. Therefore, the embodiment of the present application can realize the detection of angular velocities in two directions. Figure 2b In the related art shown, the first comb teeth 31 and the second comb teeth 32 both include a conductive layer 311 , so they can only detect acceleration in one direction. Therefore, the embodiment of the present application can improve the integration of the MEMS gyroscope.

[0118] Regarding the directions of each mode of the MEMS gyroscope, in another possible implementation, as Fig.15 As shown, the direction of the second sensing mode is the Y direction, the direction of the first sensing mode is the Y direction, and the direction of the driving mode is the Z direction.

[0119] like Fig.18 As shown, the first conductive layer 3111 of the first comb tooth pair 301, the first conductive layer 3111 of the third comb tooth pair 303, and the fourth conductive layer 3114 are all connected to the ground electrode. The second conductive layer 3112 of the first comb tooth pair 301 and the second conductive layer 3112 of the third comb tooth pair 303 can be connected to the same signal electrode, so that the second conductive layer 3112 of the first comb tooth pair 301 and the second conductive layer 3112 of the third comb tooth pair 303 can receive the same voltage signal. Of course, it can be understood that the second conductive layer 3112 of the first comb tooth pair 301 and the second conductive layer 3112 of the third comb tooth pair 303 can be connected to different signal electrodes. Figure 1b The power supply 22 shown can provide the same voltage signal to two different signal electrodes through different voltage adjustment circuits 23 .

[0120] The second conductive layer 3112 and the third conductive layer 3113 of the first comb tooth pair 301 are respectively connected to different signal electrodes to receive different voltage signals. Exemplarily, the second conductive layer 3112 of the first comb tooth pair 301 and the second conductive layer 3112 of the third comb tooth pair 303 can receive a first voltage signal, and the third conductive layer 3113 can receive a second voltage signal, and the first voltage V1 in the first voltage signal and the second voltage V2 in the second voltage signal are the same in magnitude and opposite in direction.

[0121] In this way, an electric potential difference can be formed between the first conductive layer 3111 and the third conductive layer 3113 of the first comb tooth pair 301, between the third conductive layer 3113 and the first conductive layer 3111 of the third comb tooth pair 303, between the second conductive layer 3112 and the fourth conductive layer 3114 of the first comb tooth pair 301, and between the second conductive layer 3112 and the fourth conductive layer 3114 of the third comb tooth pair 303, thereby driving the second comb tooth 32 to resonate along the Z direction and completing the driving mode of the MEMS gyroscope.

[0122] In the first sensing mode, the third conductive layer 3113 and the fourth conductive layer 3114 are both connected to the ground electrode. The first conductive layer 3111 and the second conductive layer 3112 of the second comb tooth pair 302 can be connected to the same signal electrode, and the first conductive layer 3111 and the second conductive layer 3112 of the fourth comb tooth pair 304 can be connected to the same signal electrode. The first conductive layer 3111 of the second comb tooth pair 302 and the second conductive layer 3112 of the fourth comb tooth pair 304 can be connected to different signal electrodes. Fig.16a As shown, the first conductive layer 3111 and the second conductive layer 3112 of the second comb tooth pair 302 can both receive the first voltage signal, and the first conductive layer 3111 and the second conductive layer 3112 of the fourth comb tooth pair 304 can both receive the second voltage signal, and the first voltage V1 in the first voltage signal and the second voltage V2 in the second voltage signal are of the same magnitude and opposite in direction. When the mass block 63 senses in the first sensing mode, the Coriolis force is along the Y direction.

[0123] In the second sensing mode, the third conductive layer 3113 and the fourth conductive layer 3114 are both connected to the ground electrode. The first conductive layer 3111 and the second conductive layer 3112 of the first comb tooth pair 301 can be connected to the same signal electrode, and the first conductive layer 3111 and the second conductive layer 3112 of the third comb tooth pair 303 can be connected to the same signal electrode. The first conductive layer 3111 of the second comb tooth pair 302 and the second conductive layer 3112 of the fourth comb tooth pair 304 can be connected to different signal electrodes. Fig.14As shown, the first conductive layer 3111 and the second conductive layer 3112 of the second comb tooth pair 302 can both receive the first voltage signal, and the first conductive layer 3111 and the second conductive layer 3112 of the fourth comb tooth pair 304 can both receive the second voltage signal, and the first voltage V1 in the first voltage signal and the second voltage V2 in the second voltage signal are of the same magnitude and opposite in direction. When the mass block 63 senses in the first sensing mode, the Coriolis force F is along the X direction.

[0124] and Fig.15 The principles of detecting the direction and magnitude of the angular velocity in the illustrated embodiment are the same. In this embodiment, the detection of angular velocities in two directions can also be achieved, thereby improving the integration of the MEMS gyroscope.

[0125] The present application also provides a method for manufacturing a MEMS chip 10, which is applied to Figure 4 The MEMS chip 10 shown in FIG. Fig.19 As shown, the production method may include:

[0126] S71, providing a substrate 51 and a first insulating layer 52. Fig. 20 As shown, a substrate 51 and a first insulating layer 52 are stacked.

[0127] S72, such as Fig. 20 As shown, a first conductive layer 53 is formed on the first insulating layer 52. The material of the first conductive layer 53 can be polysilicon.

[0128] In other embodiments of the present application, the step of providing an SOI substrate 51 may be used to replace steps S71 and S72 in this embodiment.

[0129] S73, forming a second insulating layer 54 on the first conductive layer 53. Fig. 20 As shown, a second insulating layer 54 is formed on a side of the first conductive layer 53 facing away from the first insulating layer 52 .

[0130] S74, such as Fig. 20 As shown, a second conductive layer 55 is formed on the second insulating layer 54 .

[0131] S75, forming a third insulating layer 56 on the second conductive layer 55. Fig. 20 As shown, a third insulating layer 56 is formed on the side of the second conductive layer 55 facing away from the second insulating layer 54 .

[0132] S76, etching the third insulating layer 56, the second conductive layer 55, the second insulating layer 54, the first conductive layer 53 and the first insulating layer 52 to obtain the first comb teeth 31, the second comb teeth 32 and the support beam 61 ( Fig. 20 ). Fig.21 As shown, a plurality of spaced gaps may be etched along the Z direction on the third insulating layer 56 , the second conductive layer 55 , the second insulating layer 54 , the first conductive layer 53 and the first insulating layer 52 , thereby forming the first comb teeth 31 and the second comb teeth 32 .

[0133] S77, etching the substrate 51 from the side of the substrate 51 away from the first insulating layer 52 to obtain the base plate 40. Fig.21 As shown, the lower substrate 51 where the first comb teeth 31 , the second comb teeth 32 and the support beam 61 are arranged can be etched away to obtain the base plate 40 .

[0134] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A micro-electromechanical system (MEMS) chip, characterized in that: include: substrate; a support beam connected to the base plate; A comb tooth pair, the comb tooth pair comprising a plurality of first comb teeth and a plurality of second comb teeth, the plurality of first comb teeth being fixed on the substrate, and the plurality of second comb teeth being fixed on the support beam; or the plurality of first comb teeth being fixed on the support beam, and the plurality of second comb teeth being fixed on the substrate; The arrangement direction of the multiple first comb teeth and the multiple second comb teeth are the same and they are arranged alternately; the first comb teeth include at least two conductive layers stacked along the thickness direction of the MEMS chip, and the second comb teeth include at least one conductive layer, and the at least one conductive layer of the first comb teeth is arranged on the same layer as the at least one conductive layer of the second comb teeth.

2. The MEMS chip according to claim 1, characterized in that: The second comb teeth include at least two conductive layers, the number of conductive layers of the first comb teeth is the same as the number of conductive layers of the second comb teeth, and the at least two conductive layers of the first comb teeth and the at least two conductive layers of the second comb teeth are respectively arranged in the same layer.

3. The MEMS chip according to claim 1, characterized in that: The second comb teeth include a conductive layer, and the at least two conductive layers of the first comb teeth include a first conductive layer and a second conductive layer; The conductive layer of the second comb teeth is disposed on the same layer as the first conductive layer, or the conductive layer of the second comb teeth is disposed on the same layer as the second conductive layer.

4. The MEMS chip according to any one of claims 1 to 3, characterized in that: The thickness of the first conductive layer of the at least two conductive layers of the first comb teeth is the same as the thickness of the second conductive layer.

5. The MEMS chip according to any one of claims 1 to 3, characterized in that: The thickness of the first conductive layer of the at least two conductive layers of the first comb teeth is different from the thickness of the second conductive layer.

6. The MEMS chip according to claim 2, characterized in that: The MEMS chip further includes a plurality of signal electrodes, the first conductive layer of the first comb teeth and the fourth conductive layer of the second comb teeth are respectively connected to different signal electrodes, and the second conductive layer of the first comb teeth and the third conductive layer of the second comb teeth are respectively connected to different signal electrodes; The first conductive layer and the third conductive layer are disposed on the same layer, and the second conductive layer and the fourth conductive layer are disposed on the same layer.

7. The MEMS chip according to any one of claims 1 to 5, characterized in that: The MEMS chip also includes a ground electrode and a plurality of signal electrodes; At least two conductive layers of the first comb teeth are connected to the ground electrode, at least two conductive layers of the second comb teeth are connected to the same signal electrode, or at least two conductive layers of the second comb teeth are connected to different signal electrodes respectively.

8. The MEMS chip according to any one of claims 1 to 5, characterized in that: The MEMS chip also includes a ground electrode and a plurality of signal electrodes; The number of the comb tooth pairs is at least two, wherein two of the comb tooth pairs are arranged opposite to each other; At least two conductive layers of the second comb teeth of each comb tooth pair are connected to the ground electrode; The first conductive layers of the first comb teeth of two relatively arranged comb tooth pairs are respectively connected to different signal electrodes, the second conductive layers of the first comb teeth of two relatively arranged comb tooth pairs are respectively connected to different signal electrodes, and the first conductive layer and the second conductive layer of the same comb tooth pair are connected to the same signal electrode.

9. The MEMS chip according to any one of claims 1 to 5, characterized in that: The MEMS chip also includes a ground electrode and a plurality of signal electrodes; The number of the comb tooth pairs is at least two, wherein two of the comb tooth pairs are arranged opposite to each other; The first conductive layers of the first comb teeth of the two comb tooth pairs arranged opposite to each other are both connected to the ground electrode, and the second conductive layers of the first comb teeth of the two comb tooth pairs arranged opposite to each other are connected to the same signal electrode; The second conductive layer and the third conductive layer of the second comb teeth are respectively connected to different signal electrodes, and the fourth conductive layer of the second comb teeth of each comb tooth pair is connected to the ground electrode; The first conductive layer and the third conductive layer are disposed on the same layer, and the second conductive layer and the fourth conductive layer are disposed on the same layer.

10. A method for manufacturing a MEMS chip, characterized in that: The production method comprises: providing a substrate; forming at least two conductive layers on the substrate; The at least two conductive layers are etched to form a support beam and a comb tooth pair; the comb tooth pair includes a plurality of first comb teeth and a plurality of second comb teeth, and the plurality of first comb teeth and the plurality of second comb teeth are arranged in the same direction and alternately; the first comb teeth include at least two conductive layers stacked in a thickness direction, and the second comb teeth include at least one conductive layer, and the at least one conductive layer of the first comb teeth and the at least one conductive layer of the second comb teeth are arranged in the same layer; The substrate is etched to form a base plate.

11. An electronic device, characterized in that: It comprises a circuit board and the MEMS chip according to any one of claims 1 to 9 or a MEMS chip manufactured by the manufacturing method of claim 10, wherein the circuit board is electrically connected to the MEMS chip.

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