WO2023020336A1

WO2023020336A1 - Method and system for manufacturing microelectromechanical system comb structure, and comb structure

Info

Publication number: WO2023020336A1
Application number: PCT/CN2022/111206
Authority: WO
Inventors: 高雨浩; 陈莎莎; 韦丽清
Original assignee: 华为技术有限公司
Priority date: 2021-08-20
Filing date: 2022-08-09
Publication date: 2023-02-23
Also published as: CN115893309A

Abstract

A method and system for manufacturing a microelectromechanical system comb structure, and a comb structure. The method comprises: separately forming a fixed member blank (302) and a movable member blank (301) of a comb structure, the fixed member blank comprising a fixed member base plate (1011) and fixed member comb teeth (1012), and the movable member blank comprising a movable member riveting portion (1021) and movable member comb teeth (1022); mounting the movable member blank onto the fixed member blank in a mounting direction perpendicular to the fixed member blank, so that the fixed member comb teeth and the movable member comb teeth are arranged at intervals; and fixing the movable member riveting portion to the fixed member base plate to form the comb structure. A comb tooth structure having the comb tooth aspect ratio higher than that of a comb tooth structure manufactured by a conventional manufacturing method can be obtained, and the consistency of gaps between the comb teeth can be ensured, thereby improving the performance of the comb tooth structure.

Description

Method, system and comb structure for fabricating a microelectromechanical system comb structure

technical field

Embodiments of the present disclosure mainly relate to the field of MEMS. More specifically, embodiments of the present disclosure relate to a method, system, and comb structure for fabricating a MEMS comb structure.

Background technique

Micro Electromechanical System (MEMS) is a micro system usually fabricated on a silicon wafer with an IC process. The preparation process of the micromechanical system includes photolithography, ion beam etching, chemical etching, wafer bonding, etc. At the same time, electrodes are prepared on the mechanical structure for control by electronic technology.

As a kind of microelectromechanical system electronic device, the microelectromechanical system comb structure, also known as a comb motor, includes the comb teeth of the fixed part and the comb teeth of the movable part that can move relative to the comb teeth of the fixed part. After positive and negative charges are respectively applied to the comb teeth of the fixed part and the comb teeth of the movable part, the comb teeth of the movable part will be subjected to electrostatic force and be displaced under the action of the electrostatic force, thereby realizing the motor function of the comb structure. In addition, MEMS comb structures can also be used as inertial sensors. When used as an inertial sensor, the movable member combs are usually connected to a spring structure. When the MEMS comb structure has inertial motion, the comb teeth of the movable part can be displaced under the action of inertial force, so that the capacitance between the comb teeth of the movable part and the comb teeth of the fixed part changes. By measuring the capacitance change between the comb teeth of the movable part and the comb teeth of the fixed part, the displacement of the comb teeth of the movable part can be determined, and thus the acceleration value of the movement can be determined, so as to realize the function of the inertial sensor.

Contents of the invention

In order to improve the driving capability or sensing performance of the manufactured MEMS comb structure, embodiments of the present disclosure provide a method and system for manufacturing the MEMS comb structure.

In a first aspect of the present disclosure, a method for manufacturing a MEMS comb structure is provided. The method includes forming a fixed element blank and a movable element blank of the comb structure, respectively, wherein the fixed element blank includes a fixed element base plate and a fixed element comb; and the movable element blank includes a movable element riveting portion and movable part comb teeth; the movable part blank is inserted on the fixed part blank in the insertion direction perpendicular to the fixed part blank, so that the fixed part comb and the movable part The comb teeth are arranged at intervals; and the riveting part of the movable part is fixed to the base plate of the fixed part to form the comb tooth structure.

According to the method of the embodiment of the present disclosure, by separately forming the blank plate of the fixed part and the blank plate of the movable part and vertically inserting the two together, it is possible to obtain a comb whose aspect ratio is higher than that of the comb structure manufactured by the traditional manufacturing method. Width ratio, and ensure the consistency of the gap between the comb teeth, thereby improving the driving performance of the comb structure as a comb motor and the sensor performance as an inertial sensor.

In an implementation manner, the method further includes adjusting the position of the blank plate of the movable element relative to the blank plate of the fixed element so that the distance between the comb teeth of the fixed element and the comb teeth of the movable element is consistent. In this way, the consistency of the spacing between the comb teeth can be further ensured, thereby improving the performance of the comb tooth structure.

In one implementation, the method further comprises inserting the movable element blank on the stationary element blank by means of a positioning member, wherein the positioning element is formed on the stationary element blank and the stationary element blank Active parts on the blank board. This way facilitates the accurate positioning of the blank plate of the movable part on the blank plate of the fixed part.

In one implementation, the inserting step further includes moving the movable part blank so that the first pre-positioning part and the second pre-positioning part of the positioning member are aligned in the insertion direction, wherein the first A pre-positioning part is formed on the movable part blank, and the second pre-positioning part is formed on the fixed part blank; and the movable part blank is further moved along the insertion direction The movable element blank is inserted into the fixed element blank so that the first pre-positioning part is engaged with the second pre-positioning part. The method enables the prepositioning of the movable part blank and the fixed part blank during the insertion process in a simple manner.

In one implementation manner, adjusting the position of the movable element blank relative to the fixed element blank includes using an image acquisition unit to acquire an image of interference fringes generated by light passing through the grating marking assembly of the positioning member; and At least one of the movable piece blank and the fixed piece blank is moved along an adjustment direction perpendicular to the insertion direction, so that the interference fringes in the image meet a predetermined rule. The method can realize precise adjustment of the position of the blank plate of the movable part in at least one direction at a lower cost.

In one implementation, adjusting the position of the movable element blank relative to the fixed element blank includes electrically connecting one of the positive pole and the negative pole of a power supply having a predetermined voltage to the movable element blank, and The other one of the positive pole and the negative pole is electrically connected to the fixed part blank; the distance between the movable part comb on the movable part blank and the fixed part comb on the fixed part blank is obtained electrostatic force; and moving the movable element blank along the arrangement direction of the movable element combs or the fixed element combs, so as to adjust the electrostatic force within a predetermined threshold range. In this way, the spacing between the comb teeth of the movable part and the comb teeth of the fixed part can be consistent with a simple structure and components.

In an implementation manner, adjusting the position of the movable element blank relative to the fixed element blank includes: moving the movable element blank along a first adjustment direction in which the comb teeth of the movable element or the comb teeth of the fixed element are arranged. The first predetermined distance until the comb teeth of the movable part and the comb teeth of the fixed part contact, and determine the first moving distance of the blank plate of the movable part when the contact force is just generated; make the blank plate of the movable part move along the moving in a second adjustment direction opposite to the first adjustment direction until the comb teeth of the movable member contact the comb teeth of the fixed member, and determine the second movement of the blank plate of the movable member when the contact force is initially generated distance; according to the first predetermined distance, the first moving distance and the second moving distance, a third moving distance for moving the movable member blank along the first adjustment direction is determined; and the The movable element blank moves the third moving distance along the first adjustment direction to make the intervals of the formed comb structures consistent. In this way, the spacing between the comb teeth of the movable part and the comb teeth of the fixed part can be consistent with a simple structure and components.

In an implementation manner, determining the first moving distance includes obtaining at least two different contact forces during the movement of the movable element blank along the first adjustment direction; obtaining the contact force and the a relationship between the moving distances of the movable member blanks; and determining the first moving distance according to the relationship.

In an implementation manner, determining the second moving distance includes obtaining at least two different contact forces during the movement of the movable member blank along the second adjustment direction; obtaining the contact force and the The relationship between the moving distances of the blank plates of the movable part; the second moving distance is determined according to the relationship.

In an implementation manner, the method further includes fixing the riveted part of the movable part to the substrate of the fixed part by an adhesive. In this way, it can be ensured that the movable part is fixed to the fixed part without deformation of the comb teeth, thereby improving the reliability of the manufactured comb structure.

According to a second aspect of the present disclosure there is provided a system for manufacturing a MEMS comb structure. The system includes an etching device configured to form a fixed element blank and a movable element blank of the comb structure, respectively, wherein the fixed element blank includes a fixed element base plate and a fixed element comb; and the movable element The blank of the movable part includes a riveting part of the movable part and comb teeth of the movable part; The direction is inserted on the blank plate of the fixing part. With this system, the aspect ratio of the comb teeth can be obtained higher than that of the comb structure manufactured by the traditional manufacturing method, and the consistency of the gap between the comb teeth can be ensured, thereby improving the drive of the comb tooth structure as a comb tooth motor performance and performance of the sensor as an inertial sensor.

In some embodiments, the system further includes a positioning member configured to provide guidance and/or positioning for the movable element blank so as to facilitate consistent comb gaps of the formed comb structure. The positioning member can facilitate the precise insertion of the blank plate of the movable part into the blank plate of the fixed part, thereby improving the performance and reliability of the manufactured comb structure.

In some embodiments, the positioning member includes a first pre-positioning part formed on the movable part blank; and a second pre-positioning part formed on the fixed part blank and configured to be compatible with The first pre-positioning part is engaged to provide guidance for the movement of the movable part blank along the insertion direction.

In some embodiments, the positioning member further includes a grating mark assembly adapted to cause interference of light passing through the grating mark assembly, comprising: a first grating mark formed on the movable member blank; a second grating Marks are formed on the fixing element blank and are configured to be perpendicular to the insertion direction with the second grating mark when the first pre-positioning element and the second pre-positioning element are engaged. Stagger each other in the adjustment direction.

In some embodiments, the positioning member further includes an alignment plate adapted to be arranged on a side of the fixed element blank that is away from the movable element blank, and the grating mark assembly further includes an alignment plate formed on the alignment plate. A plurality of alignment plate grating marks on the alignment plate, the alignment plate grating marks are arranged to be aligned with the first grating mark and the second grating mark in the insertion direction.

In some embodiments, the positioning member further includes a light source, which is arranged on a side of the alignment plate away from the fixing member blank along the insertion direction, and is configured to move toward the alignment plate along the Emitting light in the insertion direction; and an image acquisition unit, arranged on a side of the movable element base plate away from the alignment plate in the insertion direction, and configured to acquire the light passing through the grating Image of the resulting interference fringes after labeling the component.

In some embodiments, the movable blank and the fixed blank are rectangular, and the first grating mark and the second grating mark are arranged on at least one border of the rectangle.

In some embodiments, the positioning member further includes a force sensor configured to obtain the electrostatic force and the At least one of the contact forces.

According to a third aspect of the present disclosure, there is provided a MEMS comb structure manufactured by the method described in the first aspect above. The comb structure includes a fixed part, including a fixed part base plate and a fixed part comb; and a movable part, including a riveted part of the movable part, a comb of the movable part and a connecting block connecting the riveted part of the movable part and the comb of the movable part, wherein The riveting part of the movable part is adhered to the substrate of the fixed part by adhesive, so as to fix the movable part on the fixed part.

In some embodiments, the aspect ratio between the comb teeth of the movable part and the comb teeth of the fixed part of the MEMS comb structure is greater than 50:1.

Description of drawings

The above and other features, advantages and aspects of the various embodiments of the present disclosure will become more apparent with reference to the following detailed description when taken in conjunction with the accompanying drawings. In the drawings, the same or similar reference numerals indicate the same or similar elements, wherein:

Fig. 1 shows the three-dimensional schematic diagram of MEMS comb tooth structure;

Fig. 2 shows a schematic top view of the MEMS comb structure;

Fig. 3 shows the three-dimensional schematic view of the core structure in the MEMS comb structure;

Figure 4 shows a simplified schematic diagram of the electrostatic force between a pair of comb teeth when the MEMS comb tooth structure is used as a MEMS motor;

Fig. 5 shows a simplified schematic diagram of the effect of the movement between the comb teeth on the capacitance change when the MEMS comb tooth structure is used as a MEMS motor;

Fig. 6 shows the simplified cross-sectional side view schematic diagram of the comb structure corresponding to each step of the traditional method of manufacturing MEMS comb structure;

Fig. 7 shows the schematic diagram that a part of ion beam can radiate to the sidewall of comb tooth during etching process;

Fig. 8 shows a schematic diagram of the spacing between comb teeth corresponding to the manufacturing method according to some embodiments of the present disclosure;

FIG. 9 shows a schematic flow diagram of a method for manufacturing a MEMS comb structure according to some embodiments of the present disclosure;

FIG. 10 shows a simplified cross-sectional side view of a fixed member blank corresponding to each step of manufacturing a fixed member blank in a method for manufacturing a MEMS comb structure according to an embodiment of the present disclosure;

Fig. 11 shows a simplified cross-sectional side view schematic diagram of the movable element blank corresponding to each step of manufacturing the movable element blank in the method of manufacturing the MEMS comb tooth structure according to an embodiment of the present disclosure;

Fig. 12 shows a simplified cross-sectional side view corresponding to each step of inserting the movable element blank into the fixed element blank in the method for manufacturing a MEMS comb structure according to an embodiment of the present disclosure;

FIG. 13 shows a simplified perspective view of moving a movable element blank using a system for manufacturing a MEMS comb structure according to an embodiment of the present disclosure;

FIG. 14 shows a simplified schematic perspective view of a system for manufacturing a MEMS comb structure according to an embodiment of the present disclosure;

Fig. 15 shows a schematic perspective view of a movable part blank according to some embodiments of the present disclosure;

Figure 16 shows a schematic perspective view of a fastener blank according to some embodiments of the present disclosure;

Fig. 17 shows a schematic perspective view of a movable part blank fixed to a fixed part blank according to some embodiments of the present disclosure;

Fig. 18 shows a schematic perspective view of a movable part blank and a fixed part blank according to some embodiments of the present disclosure;

Fig. 19 shows a schematic perspective view of the blank of the movable part being inserted into the blank of the fixed part according to some embodiments of the present disclosure;

Fig. 20 shows a schematic perspective view of the relationship between the comb teeth of the movable part and the comb teeth of the fixed part according to some embodiments of the present disclosure;

Fig. 21 shows a schematic perspective view of adjusting the position of the blank plate of the movable part by electrostatic force according to some embodiments of the present disclosure;

Fig. 22 shows a schematic perspective view of adjusting the position of the blank of the movable element in a contact force manner according to some embodiments of the present disclosure; and

FIG. 23 shows a graph of the relationship between force and moving distance for adjusting the movable element blank in a contact force manner according to some embodiments of the present disclosure.

Detailed ways

Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the drawings, it should be understood that the disclosure may be embodied in various forms and should not be construed as limited to the embodiments set forth herein; A more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are for exemplary purposes only, and are not intended to limit the protection scope of the present disclosure.

In the description of the embodiments of the present disclosure, the term "comprising" and its similar expressions should be interpreted as an open inclusion, that is, "including but not limited to". The term "based on" should be understood as "based at least in part on". The term "one embodiment" or "the embodiment" should be read as "at least one embodiment". The terms "first", "second", etc. may refer to different or the same object. Other definitions, both express and implied, may also be included below.

Micro Electromechanical System (MEMS) is generally considered to be a micro system composed of micro sensors, micro actuators and micro electronic circuits. The research and development of MEMS mainly focuses on the research and development of miniature sensors and actuators. MEMS devices and microprocessing technology have three characteristics, namely, miniaturization, microelectronic integration and high-precision mass production. With the consumption upgrade of human society, MEMS technology ushered in explosive growth, and various types of MEMS sensors are also widely used in the fields of aerospace, petrochemical, marine automobile, home furnishing and medical health.

1 to 3 show schematic diagrams of a common MEMS device (ie, a MEMS comb structure 100 ). FIG. 1 shows a perspective view of the MEMS comb structure 100 viewed from an angle, FIG. 2 shows a top view of the MEMS comb structure 100, and FIG. 3 shows a perspective view of the core structure 103 of the comb structure 100. . As shown in FIGS. 1 to 3 , the MEMS comb structure 100 generally includes a fixed part 101 and a movable part 102 . The fixing part 101 includes a fixing part comb 1012 , a fixing part base plate 1011 and a fixing part riveting part 1013 for fixing the fixing part comb 1012 to the fixing part base plate 1011 . The movable part 102 includes a movable part comb 1022, a movable part mover 1025, a movable part riveting part 1021 and a movable part connecting part 1023 arranged between the movable part comb 1022 and the movable part riveting part 1021 and a movable part providing spring performance spring arm 1024.

From a manufacturing point of view, the MEMS comb structure 100 can be further divided into a core structure 103 and the aforementioned fixing substrate 1011 . The core structure 103 includes a fixed core structure 1031 and a movable core structure 1032 . The core structural member 1031 of the fastener includes other components of the fastener 101 mentioned above except the substrate 1011 of the fastener, such as the comb teeth 1012 of the fastener and the riveting part 1013 of the fastener. All the components of the movable part 102 mentioned above are also referred to as the movable part core structure part 1032 .

After the core structural part 103 is bonded to the fixed part substrate 1011, the movable part 102 is fixed on the proper position of the fixed part substrate 1011 by means of the riveting part 1021 of the movable part so that the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part are arranged at intervals . With the help of the connecting part 1023 of the movable part and the spring arm 1024 of the movable part, the comb teeth 1022 of the movable part can be displaced relative to the comb teeth 1012 of the fixed part, so as to realize predetermined functions. Specifically, the MEMS comb structure 100 can be used not only as a power electronic device, ie, a MEM comb motor, but also as an inertial sensor. When used as a MEMS comb motor, a predetermined voltage V is applied to the movable comb 1022 and the fixed comb 1012 to control the relative movement of the movable comb 1022 and the fixed comb 1012 . That is to say, the MEMS comb motor is driven by applying a voltage V between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part. In the MEMS comb structure 100, the capacitance is changed by changing the area rather than the plate spacing. The area here refers to the overlapping area of the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part in the arrangement direction of the comb teeth. Since capacitance has a linear relationship with area, the displacement of the comb teeth 1022 of the movable member will be proportional to the square of the applied voltage.

Specifically, the magnitude F of the electrostatic force between a pair of comb teeth of the movable part 1022 and the comb teeth of the fixed part 1012 can be calculated by the following formula (1):

Wherein e represents the dielectric constant of the medium between the fixed part comb 1012 and the movable part comb 1022, V is the applied voltage value between the movable part comb 1022 and the fixed part comb 1012, and h is the fixed part comb 1012 and the height of the comb teeth 1022 of the movable part (in the thickness direction of the substrate 1011 of the fixed part), and g is the distance between a pair of comb teeth of the fixed part 1012 and the comb teeth of the movable part 1022, as shown in FIG. 4 . As can be seen from the above formula (1), the magnitude F of the electrostatic force between the comb teeth of the movable part 1022 and the comb teeth of the fixed part 1012 is not only proportional to the dielectric constant and the voltage value, but also related to the comb teeth of the fixed part 1012 and the movable part. The aspect ratio (h/g) between the comb teeth 1022 is proportional. The aspect ratio herein refers to the ratio of the height h of the comb teeth of the fixed part 1012 or the comb teeth of the movable part 1022 to the distance g between a pair of comb teeth of the fixed part 1012 and the comb teeth of the movable part 1022 . When other factors remain unchanged, the larger the aspect ratio, the stronger the electrostatic force and the better the driving performance.

It was mentioned earlier that the MEMS comb structure 100 can also be used as an inertial sensor. Inertial sensors are devices that respond to physical motion, such as linear displacement or angular rotation, and convert this response into electrical signals that are amplified and processed by electronic circuits. Accelerometers and gyroscopes are the two most common types of MEMS inertial sensors. The accelerometer is a sensor that is sensitive to axial acceleration and converts it into a usable output signal; the gyroscope is a sensor that can sense the angular velocity of the moving body relative to the inertial space. Three MEMS accelerometers and three MEMS gyroscopes are combined to form a Micro Inertial Measurement Unit (MIMU) that can sense the linear acceleration of the carrier in three directions and the acceleration in three directions.

When the MEMS comb tooth structure 100 is used as a MEMS inertial sensor, since the comb tooth 1022 of the movable part is fixed on the substrate 1011 of the fixed part through the spring arm, when the carrier of the MEMS inertial sensor has inertial motion, the MEMS inertial sensor will also move with the inertia . The comb teeth 1022 of the movable part can be displaced under the action of inertial force, which will cause the capacitance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part to change. By detecting the change of the capacitance, the displacement of the comb teeth can be determined, and thus the magnitude of the inertial force on the comb teeth can be determined. In this way, the MEMS comb structure 100 can function as an inertial sensor.

The capacitance C between a pair of fixed member comb teeth 1012 and movable member comb teeth 1022 can be determined by the following formula (2).

Wherein as shown in Figure 5, L represents the respective lengths of the fixed part comb 1012 and the movable part comb 1022, x represents the displacement of the movable part comb 1022, h is the height of the fixed part comb 1012 and the movable part comb 1022 (in the thickness direction of the fixed member substrate 1011 ), and g is the distance between a pair of fixed member comb teeth 1012 and the movable member comb teeth 1022 . As can be seen from the above formula (2), the size of the capacitance C between a pair of fixed member combs 1012 and the movable member comb 1022 and the aspect ratio (h between the fixed member combs 1012 and the movable member comb 1022 /g) proportional to. That is to say, when other factors remain unchanged, the larger the aspect ratio, the larger the capacitance, that is, the higher the capacitance sensitivity per unit displacement, the better the performance of the inertial sensor.

The aspect ratio between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part is affected by the manufacturing process of the comb structure 100 . The manufacturing process of the conventional MEMS comb structure 100 and its existing problems will be described below with reference to FIG. 6 and FIG. 7 . FIG. 6 shows a schematic cross-sectional view of the manufacturing process of the MEMS comb structure 100 from top to bottom. In the traditional manufacturing process, the above-mentioned core structural member 103 including the fixed member core structural member 1031 and the movable member core structural member 1032 is formed through an etching process, and the core structural member 103 after etching is completed. Bonded to the fixture substrate 1011 to form the MEMS comb structure 100 . In the traditional manufacturing process, the core structural part 1031 of the fixed part and the core structural part 1032 of the movable part are completed in the same etching process.

Specifically, as shown in FIG. 2 and FIG. 6 , in the traditional manufacturing process, firstly, a photoresist 201 is applied at the position where the riveting part 1013 of the fixed part and the riveting part 1021 of the movable part are to be formed, and then exposed and developed, as in the first step shown. It should be understood that the position of coating the photoresist 201 shown in FIG. The position of the riveting part 1021 of the piece. Then, in step 2, etching and subsequent cleaning of the photoresist 201 is performed. Then in the third step, the formed blank of the core structural member 103 is turned over and the riveting part 1013 of the fixed part and the riveting part 1021 of the movable part of the core structural part 103 are fixed to the substrate 1011 of the fixed part. The most commonly used fixing method is bonding. Subsequently, in step 4, by coating the photoresist 201 and exposing the position where the movable part comb 1022, the fixed part comb 1012, the movable part mover 1025, the movable part connecting part 1023 and the movable part spring arm 1024 are to be formed development. Finally, in the fifth step, the blank of the core structure 103 is etched to form the above structure and the photoresist 201 is cleaned to form the MEMS comb structure 100 .

During the etching process in the fifth step, ideally, it is hoped that the ion beam can be irradiated between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part in a completely vertical direction. However, in the actual manufacturing process, since the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part are formed together, and the distance between the two is relatively small, even if a higher cost is spent to improve the orientation of the ion beam, but due to the process The ion beam cannot be completely perpendicular to the core structural member 103 due to the limitation of . Specifically, as shown in FIG. 7 , the larger the aspect ratio between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part, the more ion beams may not reach the bottom that needs to be irradiated, but the easier it is to irradiate To the side of the comb teeth 1012 of the fixed part or the comb teeth 1022 of the movable part. This will result in fewer ion beams reaching the bottom between the fixed member comb 1012 and the movable member comb 1022 , which ultimately makes it difficult to continue the etching process. Therefore, under the technological limitations of the current manufacturing process, the aspect ratio between the movable part comb 1022 and the fixed part comb 1012 of the MEMS comb structure 100 that can be mass-produced can be at most 30:1 to 50: 1. This places a large limitation on the driving performance of the MEMS structure when used as a motor and the sensor performance when used as an inertial sensor.

Embodiments according to the present disclosure provide a system and method for manufacturing a MEMS comb structure 100, which can solve or at least partially solve the above-mentioned problems or other potential problems existing in traditional manufacturing methods, and can obtain more efficient MEMS comb structure 100 with high aspect ratio. The system and method for manufacturing the MEMS comb structure 100 according to an embodiment of the present disclosure will be described below with reference to FIGS. 8 to 23 .

The method for manufacturing the MEMS comb-tooth structure 100 according to an embodiment of the present disclosure is to separate the fixed part 101 and the movable part 102 and insert the movable part 102 on the fixed part 101 . For distinction, the fixed part 101 and the movable part 102 in the manufacturing process will be referred to as the fixed part blank 302 and the movable part blank 301 respectively. The movable part blank 301 mainly includes the movable part riveting part 1021 and the movable part comb 1022 in addition to other components such as the aforementioned movable part mover 1025 , the movable part connecting part 1023 and the movable part spring arm 1024 . The fastener blank 302 mainly includes a fastener substrate 1011 and a fastener comb 1012 in addition to other components such as the aforementioned fastener riveting portion 1013 . In addition, for some embodiments, the fixed piece blank 302 and the movable piece blank 301 may respectively include components for providing guidance and/or positioning for the insertion process, which will be further elaborated below.

In the method for manufacturing the MEMS comb-tooth structure 100 according to an embodiment of the present disclosure, the stationary blank 302 and the movable blank 301 are formed separately, and then the movable blank 301 is perpendicular to the stationary blank. The insertion direction of 302 is inserted on the fixed part blank 302, so that the fixed part combs 1012 on the fixed part blank 302 and the movable part combs 1022 of the movable part blank 301 are arranged at intervals to thereby form a MEMS comb Tooth structure 100. Compared with the conventional method in which the comb teeth of the fixed part 1012 and the comb teeth of the movable part 1022 are formed in the same etching process, according to the method of the embodiment of the present disclosure, the original comb teeth of the movable part 1022 and the comb teeth of the fixed part 1012 are relatively small. The small spacing g will become a larger spacing b+2g between two fixed member combs 1012 or between two movable member combs 1022, as shown in Figure 8, where b is a single fixed member comb 1012 or movable The width of the comb teeth 1022 of the fixed part (in the direction in which the comb teeth of the fixed part 1012 are arranged), and g is the distance between the comb teeth of the fixed part 1012 and the comb teeth of the movable part 1022 of the MEMS comb structure 100 to be formed. Then, during the etching process, the aspect ratio between the two comb teeth in the fixed piece blank 302 or the movable piece blank 301 is h/(b+2g). After the subsequent insertion process, the aspect ratio between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part of the finally formed MEMS comb structure 100 can reach h/g.

In order to describe the improvement of the above-mentioned aspect ratio more intuitively, take h=200 μm, b=4 μm and g=2 μm in the manufactured MEMS comb structure as an example. Since the fixed part 101 or the movable part 102 is formed by etching respectively, during the etching process, the aspect ratio between the two comb teeth in the fixed part blank 302 or the movable part blank 301 is h/(b+2g) =25:1. For this aspect ratio value, the etching device can stably manufacture high-quality stationary element blanks 302 or movable element blanks 301, and the comb pitch and comb tooth spacing of the manufactured stationary element blanks 302 or movable element blanks 301 Tooth quality can reach a high quality level. Then the movable part blank 301 is vertically inserted on the fixed part blank 302 to form the MEMS comb structure 100 . Then through insertion, the aspect ratio between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part of the finally formed MEMS comb structure 100 is h/g, which can reach h/g=100:1. It can be seen that, compared to the h/g of the MEMS comb-tooth structure manufactured by the traditional manufacturing process, which is usually 30:1 and up to 50:1, the MEMS comb-tooth structure 100 manufactured by the method according to the embodiment of the present disclosure has a The aspect ratio between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part can be significantly improved, thereby improving the driving performance of the MEMS motor or the sensing performance of the MEMS relational sensor.

FIG. 9 shows a flowchart of a method of fabricating a MEMS comb structure 100 according to an embodiment of the present disclosure. As shown in FIG. 9 , at 510 , the blank plate 302 of the fixed element and the blank plate 301 of the movable element are first formed respectively. Fig. 10 shows a simplified cross-sectional view of the fixed part blank 302 in the process of forming the fixed part blank 302 using an etching device, and Fig. 11 shows a simplified cross-sectional view of the movable part blank 301 in the process of forming the movable part blank 301 . As shown in FIG. 10 , in the process of forming the fixing member blank 301 , in

steps

1 and 2, the fixing member core structure 1031 is firstly formed through an etching process. Then in step 3, the core structural member 1031 of the fastener is turned over and fixed to the substrate 1011 of the fastener, for example by bonding. Next, in

steps

4 and 5, the comb teeth 1012 of the fixing member and other necessary structures are formed through an etching process, so as to finally form the blank 302 of the fixing member on which the blank 301 of the movable member is to be inserted. It has been mentioned above that due to the large spacing between the comb teeth during the etching process, the fixing element blank 302 can be stably and accurately formed.

As shown in FIG. 11 , in the process of forming the movable part blank 301 , similar to the process of forming the fixed part blank 302 , in

steps

1 and 2, parts such as the riveting part 1021 of the movable part are etched from the first surface. Then, in the

subsequent steps

3 and 4, the core structural member 1032 of the movable part is turned over to etch the comb teeth 1022 of the movable part and other necessary structures on the opposite second surface, so as to finally form the blank plate 301 of the movable part. Due to the relatively large spacing between the comb teeth during the etching process, the movable member blank 301 can be formed stably and accurately.

The above processes of forming the fixed part blank 302 and the movable part blank 301 respectively can be performed sequentially, or can be performed simultaneously using different etching devices, so as to further improve efficiency. After the fixed piece blank 302 and the movable piece blank 301 are respectively formed, the subsequent insertion step will be carried out, that is, as shown in block 520 in FIG. 9 , the movable piece blank 301 is inserted in the insertion direction On the blank plate 302 of the fixed part, the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part are arranged at intervals. The insertion direction refers to the direction perpendicular to the blank plate 302 of the fixing element. Figure 12 shows a simplified side view of the movable element blank 301 and the stationary element blank 302 during the insertion process. After the movable part blank 301 is inserted into the proper position of the fixed part blank 302 , at 530 , the movable part riveting part 1021 is fixed to the fixed part base plate 1011 to form the comb structure 100 . The way of fixing the riveting part 1021 of the movable part to the substrate 1011 of the fixed part may be bonded with an adhesive. This can prevent the comb teeth 1022 of the movable part from being deformed during the fixing process.

In some embodiments, in order to make the space between the fixed part comb 1012 and the movable part comb 1022 of the formed MEMS comb structure 100 consistent, the movable part blank 301 is inserted on the fixed part blank 302 Afterwards, the method may also include the step of adjusting the position of the movable part blank 301 relative to the fixed part blank 302, so that the spacing between the fixed part comb 1012 and the movable part comb 1022 is consistent, thereby further improving the MEMS comb. Properties of Structure 100 .

The above method can be realized by the system for manufacturing the MEMS comb structure 100 . The system includes an etching device (not shown) and a moving device 303 . The etching device is used to respectively form the blank 301 of the movable part and the blank 302 of the fixed part according to the above-mentioned process. Inserting the movable part blank 301 onto the fixed part blank 302 and adjusting the position of the movable part comb 1022 can be realized by the moving device 303 . Figures 13 and 14 show simplified schematic diagrams of a moving device 303 according to an embodiment of the present disclosure, showing a movable part blank 301 moved by the moving device 303 and a stationary part blank 302 to be inserted. Although Fig. 13 and Fig. 14 only show that the moving device 303 transports the movable part blank 301 to be formed into a MEMS comb structure 100, it should be understood that this is only schematic. During the actual conveying process, the moving device 303 can convey the multiple rows and/or multiple rows of movable element blanks 301 to be formed with multiple MEMS comb-tooth structures 100 . Correspondingly, the fastener blanks 302 to be plugged together also have multiple rows and/or rows of fastener blanks 302 . In this way, the insertion efficiency can be improved, and finally the cost of the MEMS comb structure 100 can be reduced. Of course, in some embodiments, the moving device 303 can also be used only to move a single movable element blank 301 to be formed into a comb structure 100 , as shown in FIG. 13 . Hereinafter, the inventive concept of the present disclosure will be mainly described in the situations shown in FIG. 13 and FIG. 14 , and the situation of transporting multiple movable element blanks 301 is similar, and details will not be repeated hereafter.

In addition, Fig. 13 and Fig. 14 show that the movable part blank 301 is inserted and installed in the manner of clamping the movable part blank 301 by mechanical jaws. It should be understood that this is also illustrative and not intended to limit the protection scope of the present disclosure. Any other suitable movement or gripping is also possible. For example, in some alternative embodiments, the movable element blank 301 can be moved by means of vacuum suction, van der Waals bonding, or electrostatic adsorption. Vacuum suction is the way to grab items by creating a pressure difference through a vacuum device. Van der Waals bonding is a way of grasping objects by using non-directional, non-saturated and weak interaction forces between molecules and atoms such as adhesives. Electrostatic adsorption is a way to place items in a special area by electrostatic force. In the following, the inventive concept of the present disclosure will be described mainly with the situation shown in FIG. 13 and FIG. 14 , and other ways of moving the blank plate 301 of the movable part are also similar, and will not be repeated hereafter.

As mentioned above, in some embodiments, the fixed part blank 302 and the movable part blank 301 may respectively include components for providing guidance and/or positioning for the insertion process, and these components will be called positioning components. By means of the positioning member, the blank plate 301 of the movable part can be more reliably inserted into the blank plate 302 of the fixed part. In some embodiments, positioning members may be formed on the stationary blank 302 and the movable blank 301 , as shown in FIGS. 15 and 16 . That is to say, in the manufacturing method according to some embodiments, in addition to the aforementioned core structural components, positioning components are also included on the fixed component blank 302 and the movable component blank 301 . The positioning member may be formed together with the fixed piece blank 302 and the movable piece blank 301 through the above process of forming the fixed piece blank 302 and the movable piece blank 301 respectively. In this case, after the movable piece blank 301 is inserted onto the fixed piece blank 302 and the distance between the fixed piece comb 1012 and the movable piece 1022 is adjusted to be consistent, the positioning member can be moved along the cutting line L Cut off from the movable piece blank 301 and the fixed piece blank 302 to reach the MEMS comb structure 100 , as shown in FIG. 17 .

The specific structure of the positioning member and the process of using the positioning member to insert and adjust the movable part blank 301 according to some embodiments of the present disclosure will be described below with reference to FIGS. 13 to 17 . Specifically, in some embodiments, the positioning member may include pre-positioning parts respectively formed on the movable part blank 301 and the fixed part blank 302 . For the convenience of the following description, the pre-positioning part formed on the movable part blank 301 is called the first pre-positioning part 3011, and the pre-positioning part formed on the fixed part blank 302 is called the second pre-positioning part 3021 , as shown in Figure 13 to Figure 16. The first pre-positioning part 3011 and the second pre-positioning part 3021 can provide pre-positioning and guidance for the insertion of the movable part blank 301 .

For example, in the process of inserting the movable part blank 301, as shown in Figure 13, the movable part blank 301 is first moved to the position where the first pre-positioning part 3011 and the second pre-positioning part 3021 are positioned in the insertion direction (Fig. 13 in the Z direction) aligned position. Then, as shown in FIG. 14 , the movable part blank 301 is moved along the inserting direction, so that the movable part blank 301 is inserted into the fixed part blank 302 . During this process, the first pre-positioning member 3011 and the second pre-positioning member 3021 will engage to provide guidance for the movement of the movable part blank 301 . The "joining" here may mean that the second pre-positioning part 3021 can be inserted into the first pre-positioning part 3011 as shown in FIG. 13 and FIG. 14 . In addition, "engagement" may also refer to any other suitable means that can limit the movement of the movable part blank 301 in the direction perpendicular to the insertion direction (for example, the X direction or Y direction in the figure) beyond a predetermined threshold after the engagement. Ways, such as embedding or clamping and other ways. The restriction of movement beyond a predetermined threshold mentioned here can be achieved by a gap between the first pre-positioning member 3011 and the second pre-positioning member 3021 after engagement. In this way, even if the first pre-positioning member 3011 and the second pre-positioning member 3021 have been engaged, since there is a gap between the two, the movable part blank 301 is allowed to move in a direction perpendicular to the insertion direction (for example, X in the figure). direction or Y direction) with a small (ie, not exceeding a predetermined threshold) movement, so as to facilitate the adjustment of the movable element blank 301 to the same distance between the movable element comb 1022 and the fixed element comb 1012 .

The shapes and positions of the first pre-positioning member 3011 and the second pre-positioning member 3021 that can realize the above process can be varied. 13 to 16 show that the first pre-positioning member 3011 may be a cross-shaped through hole extending along the insertion direction. The cross-shaped through hole may be formed at a corner position of a rectangular edge of the movable member blank 301 . The second pre-positioning part 3021 that can be engaged with it is correspondingly in the form of a cross-shaped protrusion, which is also formed at the corner of the rectangular edge of the fixing part blank 302 . In addition, the positions of the vias and protrusions are also interchangeable. That is to say, in some embodiments, contrary to the way shown in FIGS. 13 to 16 , a cross-shaped protrusion can be formed on the movable part blank 301 , and a corresponding cross-shaped through hole can be formed on the fixed part blank 302 . In addition, the shapes of the through holes and the protrusions can be various besides the illustrated cross shape, for example, the shapes of the protrusions can include but not limited to cylindrical pins, rectangular pins, diamond pins or tapered pins, etc. Correspondingly, the cross-sectional shape of the through hole may include, but not limited to, a circle, a rectangle, or a rhombus, and the through hole is also in the form of a tapered blind hole. Hereinafter, the concept of the present disclosure will be described mainly in the way that the first pre-positioning member 3011 and the second pre-positioning member 3021 adopt the illustrated cross-shaped through hole and cross-shaped protrusion. It should be understood that other shapes or arrangement positions It is also possible, and will not be described in detail below.

The first pre-positioning part 3011 and the second pre-positioning part 3021 may include further pins 3013 and corresponding holes 3023 in addition to cross-shaped through holes and cross-shaped protrusions, as shown in Figures 13, 15 and 16. Show. The pin 3013 may be formed at an edge of the cross-shaped through hole and protrude toward one side of the fixing member blank 302 . A hole 3023 is formed around the cross-shaped protrusion of the fixing member blank 302 for insertion of the pin 3013 . In this way, during the insertion process of the moving part blank, the pin 3013 can cooperate with the cross-shaped protrusion of the second pre-positioning part 3021, thereby realizing the pre-positioning of the movable part blank 301 and roughly restricting the movable part blank The movement of the plate 301 in an adjustment direction perpendicular to the insertion direction (for example, the X direction or the Y direction in the figure) facilitates the precise insertion of the movable element blank 301 .

In some embodiments, in order to achieve accurate positioning of the movable part blank 301 so that the distance between the movable part comb 1022 and the fixed part comb 1012 is consistent, the positioning component may further include a grating marking assembly. The grating marker assembly is capable of interfering light passing through it to produce interference fringes. According to the principle of light interference, when the comb teeth 1022 of the movable part move a certain distance, the interference fringes generated by the moving of the grating marking component will change significantly. In the case that the distance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part is consistent, the interference fringes generated after the light passes through the grating marking assembly will show a predetermined pattern. If the spacing between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part is inconsistent, the interference fringes will be different from the predetermined law. Therefore, the process of adjusting the comb teeth 1022 of the movable part becomes the process of making the interference fringes meet the predetermined rule. In this way, compared with the way of direct visual alignment, the positioning accuracy can be further improved by using the grating marking component. In some embodiments, in order to obtain a better interference effect, the light may be single-wavelength light, such as laser light with a predetermined wavelength.

For example, in some embodiments, the positioning member may correspondingly further include a light source 305 for providing light and an image acquisition unit 306 for acquiring an interference image of the light. The light source 305 may be a single-wavelength light source 305, which is used to provide single-wavelength light to improve the interference effect and further improve the adjustment accuracy. It can be arranged on the side of the alignment plate 304 along the inserting direction away from the fixing member blank 302 , and can emit single-wavelength light along the inserting direction. In order to obtain a better interference effect, the smaller the angle between the emitted light and the insertion direction, the better, for example, preferably smaller than a predetermined threshold. In some embodiments, multiple light sources 305 may be used if one light source 305 cannot achieve an angle of light relative to the insertion direction less than the predetermined threshold.

The image acquisition unit 306 is arranged on the side of the movable part blank 301 away from the alignment plate 304 , as shown in FIG. 14 . The image acquiring unit 306 may be used to acquire the image of the interference fringes generated after the light emitted by the light source 305 passes through the grating marking component. Certainly, it should be understood that the installation positions of the image acquisition unit 306 and the light source 305 shown in FIG. 14 are indicative and are not intended to limit the protection scope of the present disclosure. Any other suitable arrangement location is also possible. For example, in some embodiments, the positions of the light source 305 and the image acquisition unit 306 may be interchanged.

In some embodiments, the lenticular marking assembly may include a first lenticular marking 3012 formed on the movable blank 301 and a second lenticular marking 3022 formed on the stationary blank 302 . The first grating mark 3012 can be formed on at least one border of the rectangular movable part blank 301, and Fig. 13, Fig. 15 and Fig. 16 show that the first grating mark 3012 is formed on four sides of the movable part blank 301. On the frame, this makes it possible to precisely adjust the position of the movable element blank 301 in multiple adjustment directions, such as the X direction and the Y direction. Certainly, in some embodiments, the first grating mark 3012 may also be formed only on one frame of the movable element blank 301 to further reduce the cost. The first grating mark 3012 includes a plurality of through grooves for light to pass through, and the size of the plurality of through grooves can make the light diffract. The first grating mark 3012 can be formed on the first section of the frame of the movable element blank 301 , and the second section of the frame can be formed as a vacancy or a through groove.

Similar to the first grating mark 3012, the second grating mark 3022 can be formed on at least one frame of the rectangular fixture blank 302, corresponding to the first grating mark 3012, the second grating mark 3022 can also be formed on the fixture The four borders of the base plate 302 allow precise adjustment of the position of the movable part base plate 301 in multiple adjustment directions. Certainly, in some embodiments, the second grating mark 3022 may also be formed only on one frame of the blank plate 302 of the fixing element, so as to further reduce the cost. The second grating mark 3022 includes gaps between a plurality of protrusions through which light can pass and the size of the gaps is such that light can be diffracted. The first grating mark 3012 and the second grating mark 3022 are staggered in the adjustment direction after the first pre-positioning part 3011 and the second pre-positioning part 3021 are engaged, so as to facilitate the occurrence of subsequent interference phenomenon. The mutual staggering of the first grating mark 3012 and the second grating mark 3022 means that the two are located at different positions on the same frame (for example, they are respectively located in the first section and the second section of the same frame), and both are inserted There is no overlap in direction. For example, the second grating mark 3022 can be formed on the section corresponding to the second section of the movable piece blank 301 of the frame of the fixed piece blank 302, so that a plurality of protrusions can be formed from the second section of the movable piece blank 301. The vacancy of the section or the passage of the slot. In this way, after the first pre-positioning part 3011 and the second pre-positioning part 3021 are engaged, that is, after the movable part blank 301 is initially inserted into the fixed part blank 302, the first grating mark 3012 and the second grating mark 3022 Along the same border, without overlapping, and with a gap in between.

In order to facilitate the occurrence of interference phenomenon, the positioning component further includes an alignment plate 304 , and the grating mark assembly may further include a plurality of alignment plate grating marks 3041 formed at predetermined positions of the alignment plate 304 . As shown in FIG. 14 , the alignment plate 304 is arranged on the side of the fixed element blank 302 away from the movable element blank 301 . A plurality of alignment plate grating marks 3041 are aligned with the first grating marks 3012 and the second grating marks 3022, thereby allowing light to pass through the alignment plate grating marks 3041, the first grating marks 3012, and the second grating marks 3022 and to interfere. In order to facilitate interference, the period of the alignment plate grating mark 3041 is different from that of the first grating mark 3012 and the second grating mark 3022 . For the first grating mark 3012, the period of the first grating mark 3012 is the sum of the size of a single groove plus the size of a single space between the grooves.

By means of the grating mark assembly, the step of adjusting the position of the movable piece blank 301 relative to the fixed piece blank 302 may include first using the image acquisition unit 306 to capture the image of the interference fringes generated after the light passes through the grating mark assembly, so as to determine the first The position error between a grating mark 3012 and the alignment plate grating mark 3041 and the position error between the second grating mark 3022 and the alignment plate grating mark 3041 to accurately determine the first grating mark 3012 and the second grating mark 3022 The positional deviation between them will be further elaborated below. Since the first grating mark 3012 and the second grating mark 3022 are respectively formed on the movable part blank 301 and the fixed part blank 302, the position deviation between the first grating mark 3012 and the second grating mark 3022 can also reflect the activity. The position deviation between the piece blank 301 and the fixing piece blank 302. In this case, at least one of the movable part blank 301 and the fixed part blank 302 is moved along an adjustment direction, such as the X direction and/or the Y direction, so that the generated interference fringes satisfy a predetermined law. The interference fringes with a predetermined pattern indicate that the position deviation between the first grating mark 3012 and the second grating mark 3022 is smaller than a predetermined threshold. In this way, compared with the way of direct visual alignment, the distance between the comb teeth of the fixed part 1012 and the comb teeth of the movable part 1022 can be kept consistent with higher precision at a lower cost.

The step of adjusting the position of the blank plate of the movable part 301 relative to the blank plate of the fixed part 302 mentioned above so that the blank plate of the movable part 301 and the blank plate of the fixed part 302 can be aligned in various ways. Hereinafter, with reference to FIG. 14 , several exemplary ways of how to use grating marks to achieve fine adjustment will be described by describing the movement of the moving part blank 301 along the Y direction to adjust the distance between the movable part comb 1022 and the fixed part comb 1012 . Of course, it should be understood that these exemplary ways are not exhaustive. In addition, in the following exemplary description, the size of the through groove of the first grating mark 3012 through which light passes, the size of the gap of the second grating mark 3022 and the size of the first grating mark 3012 and the second grating mark 3022 are mentioned. The size of the gap between all refers to the grating marks arranged on the frame along the Y direction.

In some embodiments, after the insertion step is completed, the first grating mark 3012 and the alignment plate grating mark 3041 of the alignment plate 304 can be in an aligned position by moving the movable part blank 301 (for example, making the generated The interference fringes satisfy a predetermined law), and then the second grating mark 3022 is aligned with the alignment plate grating mark 3041 by moving the blank plate 302 of the fixing member (for example, making the interference fringes satisfy a predetermined law). In some embodiments, it is also possible to first move the alignment plate 304 so that the alignment plate grating mark 3041 of the alignment plate 304 is in alignment with the first grating mark 3012 (for example, to make the interference fringes satisfy a predetermined rule), and then pass The blank plate 302 of the fixing element is moved so that the second grating mark 3022 and the grating mark 3041 of the alignment plate are in an aligned position.

By obtaining an image in which the interference fringes are in a predetermined pattern, the deviation value between the first grating mark 3012 or the second grating mark 3022 and the alignment plate grating mark 3041 can be calculated by an algorithm. The aforementioned situation where the first grating mark 3012 or the second grating mark 3022 is aligned with the alignment plate grating mark 3041 may refer to a situation where the calculated deviation value is zero. Of course, in the actual adjustment, the calculated deviation value of the interference fringes obtained from the first grating mark 3012 or the second grating mark 3022 and the alignment plate grating mark 3041 may also be non-zero. For example, in some embodiments, the movable part blank 301 can be moved first so that the light passes through the first grating mark 3012 and the alignment plate grating mark 3041. The deviation value calculated by the interference fringe after the light passes through the second grating mark 3022 and the alignment plate grating mark 3041 is also A, which means that the movable part blank 301 and the fixed part blank 302 are aligned , That is, the distance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part is consistent.

The above-mentioned case where the calculated deviation value is 0 or non-zero A is usually used when the gap size between the first grating mark 3012 and the second grating mark 3022 is the first grating mark 3012 or the second grating mark 3022 Integer multiples of the period. In some embodiments, considering process errors and other factors, the gap size between the first grating mark 3012 and the second grating mark 3022 may not be an integer multiple of the period of the first grating mark 3012 or the second grating mark 3022, but For example integer multiples + a. In this case, when adjusting the comb-tooth spacing, the movable part blank 301 can be moved first so that the light passes through the first grating mark 3012 and the alignment plate grating mark 3041. The calculated deviation value of the interference fringes is A (can be is 0 or non-zero), and then the deviation value calculated by moving the fixture blank 302 so that the light passes through the interference fringes after the second grating mark 3022 and the alignment plate grating mark 3041 is A+a.

In addition, since the grating marking components can be distributed on at least two intersecting frames of the rectangular frame, so that for the way of adjusting the comb teeth 1022 of the movable part by using the grating marking components, not only can one adjustment direction (for example, Y in FIG. 14 Direction) to adjust the position of the movable part comb 1022 so that the distance between the movable part comb 1022 and the fixed part comb 1012 is consistent, and the movable part comb can also be adjusted along another adjustment direction (such as the X direction in Figure 14) The position of the teeth 1022 is used to adjust the area of the overlapping area between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part, so as to meet the design requirements of the MEMS comb structure 100 . The way of adjusting the position of the moving part blank 301 along the X direction is similar to the above-mentioned way of adjusting the distance between the movable part comb 1022 and the fixed part comb 1012 along the Y direction, and will not be repeated below. Repeat them separately.

It can be seen from the above description that with the grating marking assembly, the position of the movable element blank 301 can be adjusted more precisely. As mentioned earlier, compared with direct visual adjustment, the adjustment accuracy of the grating marking component is higher. Generally speaking, the accuracy limit of direct visual adjustment is on the order of hundreds of nanometers, which is still the case of using higher standard equipment, which brings higher cost. By adopting the grating mark assembly, the interference fringes of the generated light can amplify the position error between the first grating mark 3012 and the second grating mark 3022 (that is, the movable piece blank 301 and the fixed piece blank 302), thereby facilitating more accurate The position of the movable part blank 301 is precisely adjusted.

In addition, the positioning member in the embodiment described above is integrally formed on the movable blank 301 and the fixed blank 302 during the process of forming the movable blank 301 and the fixed blank 302 . In this way, the positioning member and the distance and positional relationship between the comb teeth of the fixed part 1012 and the comb teeth of the movable part 1022 are always kept constant, thereby facilitating the adjustment of the distance between the comb teeth of the fixed part 1012 and the comb teeth of the movable part 1022 . After the distance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part is adjusted consistently, the riveting part 1021 of the movable part can be fixed to a predetermined position of the base plate 1011 of the fixed part by means of adhesive bonding. After this fixing step is completed, the movable element blank 301 is firmly fixed on the fixed element blank 302 . Subsequently, the MEMS comb-tooth structure 100 can be finally obtained by removing the positioning member from the fixed blank 302 and the movable blank 301 along the cutting line L, as shown in FIG. 17 .

Of course, it should be understood that this arrangement of the positioning members is only illustrative, and is not intended to limit the protection scope of the present disclosure. Any other suitable arrangement is also possible. For example, in some embodiments, the positioning member can also be independent of the fixed piece blank 302 or the movable piece blank 301 . For example, in some embodiments, a portion of the positioning member may be fixed to the mobile device 303 . After the movable part blank 301 is clamped by the moving device 303, the position of the part of the positioning member arranged on the moving device 303 and the comb teeth 1022 of the movable part can also remain unchanged, so as to meet the requirement of precise position adjustment. Similarly, the part of the positioning member that cooperates with the blank plate 302 of the fixing element can also be separated from the blank plate 302 of the fixing element. This arrangement can simplify the steps of forming the blank plate 301 of the movable part or the blank plate 302 of the fixed part, and further reduce the cost.

The above describes the way to realize the precise adjustment of the position of the blank plate 301 of the movable part by adopting the way that the positioning member includes the grating mark assembly. Of course, it should be understood that this adjustment method is only illustrative, and is not intended to limit the protection scope of the present disclosure. Any other suitable adjustment is also possible. For example, in some alternative embodiments, the positioning member may not include the above-mentioned pre-positioning member and grating marking assembly, but adopt other positioning adjustment methods. In this case, the movable part blank 301 and the fixed part blank 302 do not have other components that need to be removed eventually to form the MEMS comb structure 100 (such as the pre-positioners and grating marking components mentioned above) , as shown in Figure 18. Of course, it should be understood that, in some cases, in order to facilitate clamping, corresponding structures or devices that facilitate clamping may also be formed on the movable piece blank 301 and the fixed piece blank 302 . Other possible positioning adjustment methods will be exemplarily described below in conjunction with FIGS. 19 to 22 .

In some embodiments, the positioning member may include a force sensor 307 . The force sensor 307 may be arranged on the mobile device 303 and configured to be able to acquire the electrostatic force between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part, as shown in FIG. 19 . Electrostatic force refers to the interaction force between static charged bodies. After the movable part blank 301 and the fixed part blank 302 are applied with a predetermined voltage, positive charges and negative charges will accumulate on the movable part comb 1022 and the fixed part comb 1012 respectively. If the distance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part is consistent, the electrostatic forces will cancel each other out, and the electrostatic force measured by the force sensor 307 will be equal to zero or less than a predetermined threshold, as shown in C in Figure 20 shown. If the distance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part is inconsistent, the obtained electrostatic force may be greater than zero or less than zero, and its absolute value will also be greater than a predetermined threshold, as shown in A in Figure 20 and B are shown.

Using this principle, the movable part blank 301 can be precisely adjusted without the aforementioned pre-positioning part and grating marking assembly, but only the force sensor 307 arranged on the moving device 303 . In this case, the moving device 303 can directly grab the movable part blank 301 that will form the movable part 102 (without other positioning components) in the future and insert the movable part blank 301 on the fixed part blank 302, As shown in Figure 19. After the movable part blank 301 is inserted into the fixed part blank 302, if no adjustment is made, the movable part comb 1022 and the fixed part comb 1012 may be in the states A and B in FIG. 20 . In this state, if a predetermined voltage is applied between the movable piece blank 301 and the fixed piece blank 302, all the electrostatic forces sensed by the force sensor 307 between the fixed piece comb teeth 1012 and the movable piece comb teeth 1022 The absolute value will be greater than a predetermined threshold. At this time, it is only necessary to move the movable part blank 301 along the direction in which the comb teeth are arranged (for example, the Y direction in the figure) until the electrostatic force is equal to zero or within a predetermined threshold range, which means that the fixed part comb teeth 1012 and the movable part comb teeth 1022 Keep the spacing between them the same.

Therefore, using the force sensor 307 to obtain the electrostatic force between the fixed member comb teeth 1012 and the movable member comb teeth 1022 to adjust the position of the movable member blank 301 relative to the fixed member blank 302 may include the following steps: One of the positive pole and the negative pole of the power supply is electrically connected to the movable element blank 301 , and the other is electrically connected to the fixed element blank 302 , so that opposite charges are formed on the movable element comb 1022 and the fixed element comb 1012 . Then the force sensor 307 is used to obtain the electrostatic force between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part. Since the force sensor 307 is arranged on the mobile device 303 , the obtained electrostatic force is the resultant force of the electrostatic forces between all the comb teeth of the movable part 1022 and the comb teeth of the fixed part 1012 . If the absolute value of the electrostatic force is greater than the predetermined threshold or the electrostatic force is outside the predetermined threshold range, the distance between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part is not consistent. At this time, the movable element blank 301 can be moved along the arrangement direction of the comb teeth according to the applied charge and the direction and size of the rift, as shown in FIG. 21 , until the electrostatic force is equal to zero or within a predetermined threshold range. After that, the riveting part 1021 of the movable part can be bonded to a predetermined position of the substrate of the fixed part 1011 by an adhesive, so as to complete the fixing between the blank plate of the movable part 301 and the blank plate of the fixed part 302 . Since no positioning means such as pre-positioners and grating marker assemblies are used, there is no further step of removing the positioning means after this. In this manner, precise positioning between the movable element blank 301 and the fixed element blank 302 can be achieved with fewer components and lower costs.

In some embodiments, the force sensor 307 may also be a force sensor used to measure the contact force between the fixed member comb 1012 and the movable member comb 1022 . The contact force refers to the force generated when the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part come into contact. In this case, it is not necessary to apply a voltage on the movable part blank 301 and the fixed part blank 302, but only need to directly follow the arrangement direction of the comb teeth after the movable part blank 301 is inserted into the fixed part blank 302. (ie, the Y direction shown in FIG. 22 ) to move the movable member blank 301 .

In the case that the force sensor 307 adopts the contact force sensor 307, the method for adjusting the position of the movable piece blank 301 relative to the fixed piece blank 302 after the movable piece blank 301 is inserted can include firstly making the movable piece blank 301 move along the The first adjustment direction of the arrangement of the comb teeth, for example, the negative direction of the Y-axis moves the first predetermined distance D1 until the comb teeth 1022 of the movable part come into contact with the comb teeth 1012 of the fixed part. During this process, multiple contact force values can be measured , the three contact forces shown in triangles in Figure 23. The abscissa in Fig. 23 represents the moving distance of the movable part blank 301, wherein the zero point represents the initial position of the movable part blank 301 after the movable part blank 301 has been inserted, and the negative direction indicates that the movable part blank 301 is moved along the first level (that is, the Y direction in FIG. 22 is negative), and the positive direction means that the movable element blank 301 moves along the second moving direction opposite to the first adjustment direction (that is, the Y direction in FIG. 22 is positive). The ordinate in FIG. 23 represents the measured contact force.

By moving the movable element blank 301 along the first adjustment direction as mentioned above, multiple contact force values (three are shown in FIG. 23 ) can be obtained as shown by the triangles. Using these contact force values, the force-distance line F1 during the contact process between the comb teeth of the movable part 1022 and the comb teeth of the fixed part 1012 can be fitted. The force-distance line F1 can be used to determine the first moving distance L1 of the movable element blank 301 when the movable element blank 301 is moved in the first adjustment direction until the contact force is just generated. Here, the beginning of contact force refers to the point where the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part just start to contact.

After moving the first predetermined distance D1 along the first adjustment direction, the movable part blank 301 is moved along the opposite second predetermined direction by the second predetermined distance D2 until the movable part comb 1022 and the fixed part comb 1012 contact again, as Figure 23 shows. In this case, a plurality of contact force values are acquired again (three contact forces indicated by circles are shown in FIG. 23 ). By using the multiple contact force values, the force-distance line F2 during the contact process between the comb teeth of the movable part 1022 and the comb teeth of the fixed part 1012 can be fitted when moving along the second predetermined direction. Using the force-distance line F2, the second moving distance L2 of the movable element blank 301 can be determined when the movable element blank 301 is moved in the second adjustment direction until the contact force is just generated. It can be seen from FIG. 23 that the actual distance D between the comb teeth 1012 of the fixing member can be determined by using the following formula (3) through the first predetermined distance D1, the first moving distance L1 and the second moving distance L2.

D＝L2-D1+L1 (3)

The distance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part can be consistent only by making the comb teeth 1022 of the movable part located at the middle point Y of the actual distance D. Next, according to the determined actual distance D between the comb teeth 1012 of the fixed part, the third moving distance L3 required to move the blank plate 301 of the movable part to the point where the comb teeth 1022 of the movable part and the comb teeth of the fixed part 1012 are consistent can be determined. According to FIG. 23 and the above formula (3), the third moving distance L3 can be determined using the formula (4).

L3＝D2-L2+D/2 (4)

After the third moving distance L3 is determined, it is only necessary to move the movable part blank 301 along the first moving direction by the third moving distance L3 to move the movable part blank 301 to the movable part comb 1022 and the fixed part comb 1012 The position at which the pitches of 1 and 2 are consistent (ie, position Y in FIG. 23 ). In this way, precise positioning of the movable part blank 301 can be achieved using only the force sensor 307 . Of course, the above method of passing the distance can also be realized by determining the coordinate value.

Specifically, after making the movable part blank 301 contact the movable part comb 1022 and the fixed part comb 1012 along the first moving direction and obtain multiple contact forces, the output force-distance line F1 can be fitted by these contact forces . The S-axis coordinate Y1 when the comb teeth 1022 of the movable part first contact the comb teeth 1012 of the fixed part can be obtained by using the force-distance F1 . By the same token, the force-distance line F2 of the movable part blank 301 along the second moving direction can be obtained. Using the force-distance line F2, the coordinate Y2 when the movable member blank 301 moves along the second moving direction when the movable member comb 1022 first contacts the fixed member comb 1012 can be obtained. Y1 and Y2 can be used to determine the coordinate Y of the movable part blank 301 when the distance between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part is consistent with the following formula (5).

Y＝(Y2+Y1)/2 (5)

Next, it is only necessary to move the movable part blank 301 to the coordinate value. In this way, the spacing between the comb teeth 1012 of the fixed part and the comb teeth 1022 of the movable part is ensured to be consistent by using simpler means.

The different embodiments of inserting the movable element blank 301 into the fixed element blank 302 and adjusting the movable element blank 301 have been described above with reference to the accompanying drawings. It should be understood that the above embodiments of adjusting the position of the movable element blank 301 relative to the fixed element blank 302 are not exhaustive, and any other suitable adjustment methods are also possible. Forming the movable part blank 301 and the fixed part blank 302 by etching respectively can realize the high aspect ratio between the comb teeth of the formed MEMS comb tooth structure 100 in a simple manner and at a low cost, thus significantly improving the MEMS comb structure. The tooth structure 100 has driving performance as a MEMS motor and sensor performance as a MEMS inertial sensor.

According to another aspect of the embodiments of the present disclosure, there is also provided a MEMS comb structure 100 manufactured by the method mentioned above. The MEMS comb structure 100 includes the aforementioned fixed part 101 and movable part 102 . In the MEMS comb-tooth structure 100 manufactured by a traditional manufacturing process, the movable part 102 and the fixed part 101 are usually fixed together by bonding. As mentioned above, the MEMS comb structure 100 manufactured according to the method of the embodiment of the present disclosure can easily realize the aspect ratio between the fixed part comb 1012 and the movable part comb 1022 greater than 50:1, such as 100:1. 1, so that the driving ability or sensing performance of the MEMS comb structure 100 can be significantly improved. In addition, the riveting part 1021 of the movable part is adhered to the base plate 1011 of the fixed part by an adhesive. In this way, the deformation between the comb teeth 1022 of the movable part and the comb teeth 1012 of the fixed part generated during the bonding process can be avoided, thereby further improving the reliability of the MEMS comb structure 100 .

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are merely example forms of implementing the claims.

Claims

A method for manufacturing a microelectromechanical system comb structure, comprising:

Respectively form the fixed part blank (302) and the movable part blank (301) of the comb structure (100), wherein the fixed part blank (302) includes a fixed part base plate (1011) and a fixed part comb ( 1012); and the movable part blank (301) includes a movable part riveting part (1021) and a movable part comb (1022);

The movable part blank (301) is inserted on the fixed part blank (302) in an insertion direction perpendicular to the fixed part blank (302), so that the fixed part comb (1012) ) and the movable member comb teeth (1022) are arranged at intervals; and

The riveting part (1021) of the movable part is fixed to the substrate (1011) of the fixed part to form the comb structure (100).
The method according to claim 1, further comprising:

The position of the movable part blank (301) relative to the fixed part blank (302) is adjusted so that the distance between the fixed part comb (1012) and the movable part comb (1022) is consistent.
The method according to claim 2, wherein the inserting step comprises:

inserting the movable piece blank (301) on the fixed piece blank (302) by means of a positioning member, wherein the positioning member is formed on the fixed piece blank (302) and the movable piece piece blank (301).
The method according to claim 3, wherein the inserting step further comprises:

moving the movable part blank (301) so that the first pre-positioning part (3011) and the second pre-positioning part (3021) of the positioning member are aligned in the insertion direction, wherein the first pre-positioning A member (3011) is formed on the movable member blank (301), and the second pre-positioning member (3021) is formed on the fixed member blank (302); and

moving the movable part blank (301) further along the inserting direction so that the first pre-positioning part (3011) and the second pre-positioning part (3021) are engaged to insert the movable part blank The plate (301) is inserted on the blank plate (302) of the fixing element.
The method according to any one of claims 2-4, wherein adjusting the position of the movable element blank (301) relative to the fixed element blank (302) comprises:

using an image acquisition unit (306) to acquire an image of interference fringes generated by light passing through the grating marking assembly of the positioning member; and

At least one of the movable piece blank (301) and the fixed piece blank (302) is moved along an adjustment direction perpendicular to the insertion direction, so that the interference fringes in the image meet a predetermined law.
The method according to claim 2, wherein adjusting the position of the movable member blank (301) relative to the fixed member blank (302) comprises:

One of the positive pole and the negative pole of a power supply having a predetermined voltage is electrically connected to the movable piece blank (301), and the other of the positive pole and the negative pole is electrically connected to the fixed piece blank (302 );

obtaining the electrostatic force between the comb teeth (1022) of the movable part on the base plate of the movable part (301) and the comb teeth (1012) of the fixed part on the blank plate of the fixed part (302); and

The movable part blank (301) is moved along the arrangement direction of the movable part combs (1022) or the fixed part combs (1012), so as to adjust the electrostatic force within a predetermined threshold range.
The method according to claim 2, wherein adjusting the position of the movable member blank (301) relative to the fixed member blank (302) comprises:

Make the movable piece blank (301) move a first predetermined distance along the first adjustment direction where the movable piece combs (1022) or the fixed piece combs (1012) are arranged until the movable piece combs (1022) and the fixed piece combs (1012) are aligned. The comb teeth (1012) of the fixed part are in contact, and the first moving distance of the blank plate of the movable part (301) is determined when the contact force is first generated;

Make the movable part blank (301) move along the second adjustment direction opposite to the first adjustment direction until the movable part comb (1022) contacts the fixed part comb (1012), and determine just a second moving distance of the movable element blank (301) when the contact force begins to be generated;

determining a third moving distance for moving the movable member blank (301) along the first adjustment direction according to the first predetermined distance, the first moving distance, and the second moving distance; and

The movable part blank (301) is moved along the first adjustment direction by the third moving distance to make the intervals of the formed comb structures (100) consistent.
The method of claim 7, wherein determining the first moving distance comprises:

obtaining at least two different contact forces during the movement of the movable member blank (301) along the first adjustment direction;

Obtaining the relationship between the contact force and the moving distance of the movable element blank (301); and

The first moving distance is determined according to the relationship.
The method of claim 7, wherein determining the second movement distance comprises:

obtaining at least two different contact forces during the movement of the movable member blank (301) along the second adjustment direction;

Obtaining the relationship between the contact force and the moving distance of the movable part blank (301);

The second moving distance is determined according to the relationship.
The method according to any one of claims 1-9, further comprising:

The riveting part (1021) of the movable part is fixed to the substrate (1011) of the fixed part by an adhesive.
A system for fabricating microelectromechanical system comb structures, comprising:

An etching device configured to form a fixed member blank (302) and a movable member blank (301) of the comb structure (100) respectively, wherein the fixed member blank (302) includes a fixed member substrate ( 1011) and the fixed part comb (1012); and the movable part blank (301) includes the movable part riveting part (1021) and the movable part comb (1022); and

The moving device (303) is configured to be coupled to the movable element blank (301), so as to insert the movable element blank (301) in an insertion direction perpendicular to the fixed element blank (302) on the fixing member blank (302).
The system of claim 11, further comprising:

The positioning member is configured to provide guidance and/or positioning for the movable element base plate (301) to facilitate the consistency of comb gaps of the formed comb structure (100).
The system of claim 12, wherein the positioning member comprises:

The first pre-positioning part (3011) is formed on the movable part blank (301); and

The second pre-positioning part (3021) is formed on the fixed part blank (302), and is configured to be able to engage with the first pre-positioning part (3011) to provide the movable part blank (301) ) provides guidance along the direction of insertion.
The system of claim 13, wherein the positioning member further comprises:

A grating marking assembly adapted to cause interference of light passing through said grating marking assembly, comprising:

A first grating mark (3012), formed on the movable member blank (301);

A second grating mark (3022) formed on the fixture blank (302) and configured to engage the first pre-positioner (3011) and the second pre-positioner (3021) Staggered with the second grating mark (3022) in the adjustment direction perpendicular to the insertion direction.
The system of claim 14, wherein the positioning member further comprises:

an alignment plate (304), adapted to be arranged on a side of the fixed element blank (302) away from the movable element blank (301), and

The grating mark assembly also includes a plurality of alignment plate grating marks (3041) formed on the alignment plate (304), and the alignment plate grating marks (3041) are arranged in the insertion direction Aligned with said first grating mark (3012) and said second grating mark (3022).
The system of claim 15, wherein the positioning member further comprises:

The light source (305) is arranged on the side of the alignment plate (304) away from the fixing member blank (302) along the insertion direction, and configured to face the alignment plate (304) along the emitting light in the insertion direction; and

an image acquisition unit (306), arranged on a side of the movable element base plate (301) away from the alignment plate (304) in the insertion direction, and configured to acquire the light passing through the Image of the interference fringes produced after the grating marking assembly described above.
The system according to claim 16, wherein said moving said movable member blank (301) and said fixed member blank (302) are rectangular, and said first grating mark (3012) and said second Raster markings (3022) are arranged on at least one border of the rectangle.
The system of claim 12, wherein the positioning member further comprises:

A force sensor (307), configured to obtain the difference between the comb teeth (1022) of the movable part (1022) on the base plate of the movable part (301) and the comb teeth (1012) of the fixed part (1012) of the fixed part (302) At least one of electrostatic force and contact force between them.
A MEMS comb structure, comprising:

A fixture (101), including a fixture substrate (1011) and a fixture comb (1012); and

The movable part (102) includes the riveting part (1021) of the movable part, the comb teeth (1022) of the movable part and the connecting block (1023) connecting the riveting part (1021) of the movable part and the comb teeth (1022) of the movable part, wherein the The riveting part (1021) of the movable part is adhered to the base plate (1011) of the fixed part by an adhesive, so as to fix the movable part (102) on the fixed part (101).
The microelectromechanical system comb structure according to claim 19, wherein the aspect ratio between the comb teeth (1022) of the movable part and the comb teeth (1012) of the fixed part of the comb tooth structure of the micro electromechanical system is greater than 50:1.