Micro-electro-mechanical structure and preparation method

Abstract

The invention relates to the field of micro electro mechanical systems, in particular to a micro electro mechanical system structure and a preparation method, the micro electro mechanical system structure comprises a bearing layer and a covering layer which are stacked and bonded with each other, a plurality of bonding parts are formed on the surface, close to the covering layer, of the bearing layer, and the covering layer covers the bearing layer and is tightly connected through the bonding parts. A plurality of through holes are formed in the surface of the covering layer, the through holes are used for communicating the two sides of the covering layer, the covering layer comprises a target area and a plurality of detection areas, the depth of the detection areas is consistent with that of the through holes in the target area, the detection areas of the covering layer can be separated from the bearing layer through a mechanical method, and / or the detection areas are formed in a non-functional area of the micro-electro-mechanical structure. Through holes with the same depth are formed in the detection area with the structure not affecting the product function, and the depth of the through holes in the detection area is obtained through destructive testing, so that the etching condition of the through holes in the functional area is judged, the universality is high, the product is not damaged, and the cost is low.

Description

Technical Field

[0001] The present invention relates to the field of micro-electromechanical systems, and in particular to a micro-electromechanical system structure and a preparation method thereof. Background Art

[0002] In micro-electromechanical systems, it is often necessary to etch a through hole connected to the cavity in the cover layer bonded to the cavity surface. In production, each batch of products needs to be tested to see if the through hole penetrates the cavity. However, destructive testing will cause the product to be damaged and difficult to use, which is costly.

[0003] At present, the main method that does not damage the product is optical detection method. However, optical detection has high limitations. For example, the depth of the structure etched above the cavity can be detected through an electron microscope, or whether the cavity below can be seen through the etched area to determine whether the etching is complete. However, this method is only applicable to the case where the through hole is formed in a thin and transparent film layer, and has great limitations. Summary of the invention

[0004] The object of the present invention is to provide a micro-electromechanical structure and a preparation method which can detect the corrosion of the cover layer without affecting the product function and has a wide range of applications.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A micro-electromechanical structure comprises a carrier layer and a covering layer which are stacked and bonded to each other, a plurality of bonding portions are formed on the surfaces where the carrier layer and the covering layer are bonded, the covering layer is tightly connected to the carrier layer via the bonding portions, a plurality of through holes are formed on the surface of the covering layer, the through holes are used to connect the two sides of the covering layer, the covering layer comprises at least one target area and at least one detection area corresponding to each target area, each target area comprises the through hole, the detection area is provided with the through hole of the same depth as the through hole in the corresponding target area, the detection area of ​​the covering layer can be separated from the carrier layer by a mechanical method, and / or the detection area is formed in a non-functional area of ​​the micro-electromechanical structure.

[0007] Optionally, a projection of the bonding portion on the covering layer is far away from the detection area and the functional area, and a thickness of the detection area is equal to a thickness of the target area.

[0008] Optionally, the microelectromechanical structure is provided with a plurality of separation grooves surrounding the detection area, and the separation grooves at least penetrate the covering layer, and a partial area of ​​the covering layer surrounded by the plurality of separation grooves around each detection area forms a disassembly block, and the disassembly block is directly connected to other parts of the covering layer, and / or the disassembly block is connected to the supporting layer through the bonding portion.

[0009] Optionally, projections of at least part of the separation grooves on the carrier layer pass through any of the bonding portions.

[0010] Optionally, adjacent detection intervals are provided with a plurality of groups of the separation grooves and the bonding portions corresponding to each other.

[0011] Optionally, a plurality of cavities are formed on a side of the bearing layer close to the covering layer, and the through holes are used to connect the cavities.

[0012] Optionally, an area of ​​the bonding portion is smaller than a contact area between the bearing layer and the covering layer.

[0013] In a second aspect, the present invention further provides a method for preparing a micro-electromechanical structure, comprising:

[0014] Providing a bearing layer and a bonding portion formed on a surface of the bearing layer;

[0015] The covering layer is tightly connected to the supporting layer through the bonding portion, and the surface of the covering layer has a detection area and a target area;

[0016] Etching the surface of the cover layer to form a plurality of through holes with the same depth in the detection area and the target area respectively;

[0017] Detecting the depth of the through hole in the detection area, and judging the etching condition of the through hole in the functional area according to the depth of the through hole in the detection area;

[0018] The detection area is formed in a non-functional area of ​​the micro-electromechanical structure, and / or the detection area of ​​the cover layer can be separated from the carrier layer by a mechanical method.

[0019] Optionally, when the detection area is formed in a non-functional area of ​​the micro-electromechanical structure, detecting the depth of the through hole in the detection area includes:

[0020] cutting the through hole in the detection area and observing the cross section of the through hole;

[0021] and / or

[0022] The detection area is separated from the supporting layer by the mechanical method, and the side of the detection area close to the supporting layer is observed.

[0023] Optionally, separating the detection area from the bearing layer by the mechanical method comprises:

[0024] A plurality of separation grooves surrounding the detection area are formed on the surface of the cover layer, the separation grooves at least penetrate the cover layer, and a partial area of ​​the cover layer surrounded by the plurality of separation grooves around each detection area forms a disassembly block;

[0025] The disassembly block is disassembled along the separation groove to separate the disassembly block from the bearing layer and the rest of the covering layer.

[0026] According to the first aspect of the present invention, a group of through holes with the same through hole depth as that of the target area are formed in the detection area by synchronous etching and controlling parameters such as key dimensions of the graphics. When the detection area is formed in a non-functional area of ​​the micro-electromechanical structure, destructive testing of the detection area will not affect the function of the product itself. When the detection area is set in a position in the functional area that does not affect the functional design of the product, and the detection area can be separated from the bearing layer by mechanical methods, only the detection area can be disassembled by mechanical methods, and the depth of the through hole in the detection area can be checked to determine the depth of the through hole in the target area. This structure can detect the etching depth of the through hole in the target area without damaging the structure of the target area. And detection through this structure has high universality and can be widely used in products with different structures and materials. In addition, when it is detected that the etching depth of the through hole in the inspection area is small and not completely etched, etching can continue, and another inspection area can be used to determine whether the etching is complete, thereby facilitating the determination of the time required for etching, and the final product obtained can meet the functional requirements without loss. Therefore, the structure of the present invention helps to reduce losses in the process of adjusting etching conditions and in preparation, save costs, and help to conduct more frequent inspections of the prepared products, thereby helping to improve product yield.

[0027] Furthermore, since the thickness and through-hole depth in the detection area and the functional area are equal, whether the through-hole in the functional area is connected to the bearing layer can be judged by whether the detection area is etched through, which is convenient for observation and detection.

[0028] Furthermore, by setting a separation groove surrounding the detection area, the detection area is separated from the rest of the covering layer through the separation groove, so that it is convenient to remove the disassembly block including the detection area separately for observation and inspection by mechanical means such as prying. The disassembly block is connected to the bearing layer through a bonding portion; and / or the disassembly block is directly connected to other parts outside the separation groove, that is, the separation groove does not completely surround the detection area, and there is a gap between adjacent separation grooves, which helps to maintain the mechanical strength of the detection area and prevent the detection area from completely falling off from other parts of the structure under the action of the separation groove, resulting in different through-hole etching conditions in the detection area and the target area, and facilitates the bonding of the disassembly block to the upper structure away from the bearing layer.

[0029] Furthermore, the projection of the separation groove on the bearing layer passes through the bonding portion, so that after the disassembly block is peeled off the bearing layer along the separation groove, the edge portion of the separation of the covering layer is still connected to the bearing layer through the bonding portion, which helps to maintain the connection strength between the covering layer and the bearing layer and prevent the covering layer from being peeled off the bearing layer or being damaged at the separated edge.

[0030] Furthermore, an anchor point connected to the supporting layer is formed on the side of the detection area close to another detection area, which is convenient for selectively separating any disassembly block, facilitating multiple detections of the etching conditions of the through holes in the functional area through multiple disassembly blocks, and facilitating multiple experiments to explore the etching time required for the through holes to completely penetrate the functional area.

[0031] Furthermore, when the bearing layer and the covering layer are connected by non-direct bonding methods such as adhesives and molten metals, reducing the connection area between the disassembly block and the bearing layer helps to reduce the difficulty of mechanically separating the disassembly block from the bearing layer, thereby facilitating obtaining a separate disassembly block and conducting inspections.

[0032] According to the second aspect of the present invention, by forming a through hole in the detection area with the same depth while etching the through hole in the target area, it is helpful to judge the etching condition of the through hole in the target area by the depth of the through hole in the detection area without damaging the structure of the target area.

[0033] Furthermore, when the detection area is formed in the functional area, it is necessary to separate the detection area for testing without damaging other structures. When the detection area is formed in the non-functional area, the detection area can be separated, or destructive testing can be directly carried out without affecting the functional area, that is, only the non-functional area structure is destroyed without damaging the functional area structure, both of which help to maintain the function of the product.

[0034] Furthermore, the critical dimension of the area where the separation groove is located is larger than the target area and the detection area, and after being etched simultaneously, the depth of the separation groove is greater than the through hole. By prying open the joint between the bearing layer and the covering layer on the inner wall of the separation groove surrounding the detection area, it is helpful to completely peel off the disassembly block including the detection area, which is convenient for detecting the depth of the through hole.

[0035] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic cross-sectional structure diagram of a target area and a corresponding bearing layer of a micro-electromechanical structure shown in the first embodiment of the present invention;

[0037] Figure 2 It is a structural schematic diagram of multiple detection areas and corresponding bearing layers of the micro-electromechanical structure shown in the first embodiment of the present invention;

[0038] Figure 3 Flow chart of a method for preparing a micro-electromechanical structure shown in Embodiment 1 of the present invention.

[0039] Legend: 1-covering layer, 11-through hole, 121-first separation groove, 122-second separation groove, 123-third separation groove, 2-carrying layer, 211-first bonding portion, 212-second bonding portion, 22-cavity. DETAILED DESCRIPTION

[0040] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0042] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] See also Figure 1 and Figure 2 The micro-electromechanical structure protected by the present invention includes a carrier layer and a covering layer which are stacked and bonded to each other. A plurality of bonding portions are formed on the surfaces where the carrier layer and the covering layer are bonded. The covering layer is tightly connected to the carrier layer through the bonding portions. A plurality of through holes are formed on the surface of the covering layer. The through holes are used to connect the two sides of the covering layer. The covering layer includes at least one target area and at least one detection area corresponding to each target area. Each target area includes a through hole. The detection area is provided with a through hole of the same depth as the through hole in the corresponding target area. The detection area of ​​the covering layer can be separated from the carrier layer by mechanical methods, and / or the detection area is formed in a non-functional area of ​​the micro-electromechanical structure.

[0045] By means of synchronous etching and controlling parameters such as key dimensions of the pattern, a group of through holes 11 with the same depth as the through holes 11 in the target area are formed in the detection area. Among them, the target area refers to the area where through holes constituting a specific pattern need to be formed according to the layer design of the micro-electromechanical structure, that is, the area where the target structure is formed by etching. When the detection area is formed in the non-functional area of ​​the micro-electromechanical structure, destructive testing of the detection area will not affect the function of the product itself. When the detection area is set at a position in the functional area that does not affect the functional design of the product, and the detection area can be separated from the bearing layer 2 by mechanical methods, only the detection area can be disassembled by mechanical methods, and the depth of the through hole 11 in the detection area can be checked, so as to judge the depth of the through hole 11 in the target area. This structure can detect the etching depth of the through hole 11 in the target area by a method that does not damage the structure of the target area. And detection through this structure has high universality and can be widely used in products of different structures and materials. In addition, when it is detected that the etching depth of the through hole 11 in the detection area is small and not completely etched, etching can continue, and another detection area can be used to determine whether the etching is complete, so as to facilitate the determination of the time required for etching, and the final product can meet the functional requirements without loss. Therefore, the structure of the present invention helps to reduce losses in the process of adjusting etching conditions and in preparation, save costs, and help to conduct more frequent inspections of the prepared products, which helps to improve product yield.

[0046] See also Figure 3 The method for preparing the micro-electromechanical structure to be protected by the present invention comprises:

[0047] S1. Provide a carrier layer 2 and a bonding portion formed on a surface of the carrier layer 2.

[0048] S2. The covering layer 1 is tightly connected to the supporting layer 2 through a bonding portion, and the surface of the covering layer 1 has a detection area and a target area.

[0049] S3, etching the surface of the cover layer 1 to form a plurality of through holes 11 with the same depth in the detection area and the target area respectively.

[0050] S4. Detect the depth of the through hole in the detection area, and determine the etching condition of the through hole in the functional area according to the depth of the through hole in the detection area.

[0051] The detection area is formed in a non-functional area of ​​the micro-electromechanical structure, and / or the detection area of ​​the cover layer 1 can be separated from the carrier layer 2 by a mechanical method.

[0052] By forming the through hole 11 of the detection area with the same depth while etching the through hole 11 of the target area, it is helpful to judge the etching condition of the through hole 11 of the target area by the depth of the through hole 11 of the detection area without damaging the structure of the target area.

[0053] Please refer to the following examples for details.

[0054] Embodiment 1:

[0055] See also Figure 3 The method for preparing a micro-electromechanical structure shown in a preferred embodiment of the present application includes:

[0056] S1. Provide a carrier layer 2 and a bonding portion formed on a surface of the carrier layer 2.

[0057] S2. The covering layer 1 is tightly connected to the supporting layer 2 through a bonding portion, and the surface of the covering layer 1 has a detection area and a target area.

[0058] S3, etching the surface of the cover layer 1 to form a plurality of through holes 11 with the same depth in the detection area and the target area respectively.

[0059] S4, detecting the depth of the through hole 11 in the detection area, and judging the etching condition of the through hole 11 in the functional area according to the depth of the through hole 11 in the detection area.

[0060] In step S1, the carrier layer 2 has a first region and a second region. Figure 1 and Figure 2 According to the functional design requirements, a rectangular cavity 22 with a top opening is etched in the first area of ​​the carrier layer 2, and another four cavities 22 arranged in two rows and two columns are formed in the second area. The second area is located in the functional area of ​​the micro-electromechanical structure, and the structure of the second area of ​​the carrier layer 2 will not affect the product function. In this embodiment, an adhesive is applied to the surface of the carrier layer 2 away from each cavity 22 to form a bonding portion. In the second area, the bonding portion only covers part of the upper surface of the carrier layer 2, thereby reducing the connection strength. In this embodiment, a rectangular frame-shaped first bonding portion 211 is formed to surround four cavities 22 at the same time, and five rectangular block-shaped second bonding portions 212 are formed, so that there is a second bonding portion 212 between any two cavities 22, and each second bonding portion 212 is located in the middle between adjacent cavities 22.

[0061] In step S2, after bonding is completed, the portion of the covering portion corresponding to the cavity 22 in the first area is the target area, and the portion of the covering portion corresponding to the cavity 22 in the second area is the detection area. The overall thickness of the covering portion is uniform, so the target area and the detection area have the same thickness.

[0062] In step S3, a pattern that meets the functional design requirements is etched in the target area of ​​the cover layer 1, and the pattern is formed by a plurality of through holes 11 whose shapes meet the design requirements. At the same time, a plurality of through holes 11 are etched in each detection area of ​​the cover layer 1, and the key dimension parameter of the pattern is kept consistent with that of the target area through pattern design in each detection area. Since the etching of the target area and the detection area is carried out synchronously under the same conditions, the depth of the through holes 11 in the target area and the detection area is the same.

[0063] In step S3, etching of the through hole 11 and etching of the separation groove are performed simultaneously, and the method includes:

[0064] A plurality of separation grooves surrounding the detection area are formed on the surface of the covering layer 1 , the separation grooves at least penetrate the covering layer 1 , and a partial area of ​​the covering layer 1 surrounded by the plurality of separation grooves around each detection area forms a disassembly block.

[0065] The separation groove and the through hole 11 are obtained by synchronous etching. Since the critical dimension of the pattern in the area where the separation groove is located is larger than the detection area, the depth of the separation groove is greater than the through hole 11 and is connected to the carrier layer 2.

[0066] The separation grooves include four first separation grooves 121 configured in a right angle, four second separation grooves 122 configured in a straight line, and six third separation grooves 123 configured in a straight line. The four first separation grooves 121 form a rectangular shape, and the four first separation grooves 121 are respectively arranged between the first bonding portion 211 and each detection area. The four second separation grooves 122 and the four first separation grooves 121 together form a rectangular shape, and any second separation groove 122 is located between two adjacent first separation grooves 121. The projections of the six third separation grooves 123 on the carrier layer 2 respectively pass through the middle of each second bonding portion 212, wherein the second bonding portion 212 located in the middle corresponds to two third separation grooves 123 arranged in a "cross" shape, so that the six third separation grooves 123 are arranged in a "cross" shape as a whole, and are located in the middle of the rectangle surrounded by the first separation groove 121 and the second separation groove 122.

[0067] The plurality of separation grooves enclose four mutually independent rectangular disassembly blocks in the portion of the covering layer 1 corresponding to the second region of the carrier layer 2, and each disassembly block includes a detection area. Except for the two third separation grooves 123 that cross each other, each separation groove is far away from other separation grooves, so that the disassembly blocks are directly connected to other parts of the carrier layer 2, and at the same time connected to the second region of the carrier layer 2 through the second bonding portion 212.

[0068] In step S4, the corresponding disassembly block is disassembled along any second separation groove 122 to completely separate the disassembly block from the other parts of the carrier layer 2 and the cover layer 1. The side of the disassembly block close to the cavity 22 is observed under a microscope to determine whether the through hole 11 penetrates the disassembly block, thereby determining whether the through hole 11 in the target area is completely etched through.

[0069] In this embodiment, the disassembly is performed by prying. When the through hole 11 on the disassembly block does not completely penetrate the disassembly block, the micro-electromechanical structure can be placed back in the etching machine for supplementary etching. After completion, another disassembly block is separated again for judgment until the through hole 11 on the disassembly block is completely penetrated. At this time, the through hole 11 in the target area is completely etched through, the product is qualified, and the required etching conditions are obtained.

[0070] After any disassembly block is separated from the carrier layer 2, a residual groove connecting the carrier layer 2 is left on the cover layer 1. Since the area where the residual groove is located has no effect on the function of the micro-electromechanical structure, and each edge of the residual groove is connected to the carrier layer 2 through a bonding portion, it is not easy to be damaged, resulting in the residual groove not having an adverse effect on the function of the micro-electromechanical structure. When it is detected that the through hole 11 is not penetrated for supplementary etching, since the etching conditions are targeted at the cover layer 1 material and the intensity of the supplementary etching is relatively small, the supplementary etching has little impact on the structure of the carrier layer 2 exposed by the residual groove. Since the area where the residual groove is located has no effect on the function of the micro-electromechanical structure, the change in the structure of the carrier layer 2 can be ignored and will not affect the function of the micro-electromechanical structure, and the product is still a qualified product.

[0071] The micro-electromechanical structure prepared by the method of this embodiment can conduct a general inspection or a high-frequency spot inspection on the etching conditions of the through hole 11 without causing product loss, which is beneficial to saving costs and improving product yield.

[0072] Embodiment 2:

[0073] The only difference between this embodiment and the first embodiment is that in this embodiment, the carrier layer 2 and the covering layer 1 are connected by direct wafer bonding, the four detection parts correspond to the same larger rectangular cavity 22, and five columns for connecting the covering layer 1 extend from the bottom of the cavity 22, thereby providing the same first bonding part 211 and second bonding part 212 as in the first embodiment.

[0074] Embodiment three:

[0075] The only difference between this embodiment and the first embodiment is that in this embodiment, the second area and the detection area are both formed in the cutting path of the non-functional area.

[0076] Embodiment 4:

[0077] The only difference between this embodiment and the third embodiment is that the bonding portion area is larger in this embodiment, the surfaces in contact with the covering portion in the second region are coated with adhesive, and in step S4, the through hole 11 in the second region and the detection region is directly cut open along the cutting path direction, and it is determined by observing the cross section whether the through hole 11 is etched through.

[0078] The beneficial effects of the present invention are: it is easy to detect the etching depth of suspended structures of different structures and materials. The overall operation of the method is simple, and no product loss will occur, and the cost is low. It is easy to obtain suitable etching conditions in the early stage of production.

[0079] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A micro-electromechanical structure, characterized in that: The invention comprises a carrier layer (2) and a cover layer (1) which are stacked and bonded to each other, wherein a plurality of bonding portions are formed on the surfaces where the carrier layer (2) and the cover layer (1) are bonded to each other, and the cover layer (1) is tightly connected to the carrier layer (2) via the bonding portions, and a plurality of through holes (11) are formed on the surface of the cover layer (1), and the through holes (11) are used to connect two sides of the cover layer (1), and the cover layer (1) comprises at least one target area and at least one detection area corresponding to each target area, and each target area comprises the through hole (11), and the detection area is provided with the through hole (11) of the same depth as the through hole (11) in the corresponding target area, and the detection area of ​​the cover layer (1) can be separated from the carrier layer (2) by a mechanical method, and / or the detection area is formed in a non-functional area of ​​the micro-electromechanical structure.

2. The micro-electromechanical structure according to claim 1, characterized in that: The projection of the bonding portion on the covering layer (1) is far away from the detection area and the functional area, and the thickness of the detection area is equal to the thickness of the target area.

3. The micro-electromechanical structure according to claim 2, characterized in that: The micro-electromechanical structure is provided with a plurality of separation grooves surrounding the detection area, wherein the separation grooves at least penetrate the covering layer (1), and a partial area of ​​the covering layer (1) surrounded by the plurality of separation grooves around each detection area forms a disassembly block, wherein the disassembly block is directly connected to other parts of the covering layer (1), and / or the disassembly block is connected to the supporting layer (2) via the bonding portion.

4. The micro-electromechanical structure according to claim 3, characterized in that: The projection of at least part of the separation groove on the supporting layer (2) passes through any of the bonding parts.

5. The micro-electromechanical structure according to claim 4, characterized in that: A plurality of groups of the separation grooves and the bonding parts corresponding to each other are arranged adjacent to the detection sections.

6. The micro-electromechanical structure according to any one of claims 1 to 5, characterized in that: A plurality of cavities (22) are formed on the side of the bearing layer (2) close to the covering layer (1), and the through holes (11) are used to connect the cavities (22).

7. The micro-electromechanical structure according to any one of claims 1 to 5, characterized in that: The area of ​​the bonding portion is smaller than the contact area between the carrier layer (2) and the cover layer (1).

8. A method for preparing a micro-electromechanical structure, characterized in that: include: Providing a carrier layer (2) and a bonding portion formed on the surface of the carrier layer (2); The covering layer (1) is tightly connected to the supporting layer (2) through the bonding portion, and the surface of the covering layer (1) has a detection area and a target area; Etching the surface of the cover layer (1) to form a plurality of through holes (11) of the same depth in the detection area and the target area respectively; Detecting the depth of the through hole (11) in the detection area, and judging the etching condition of the through hole (11) in the functional area according to the depth of the through hole (11) in the detection area; The detection area is formed in a non-functional area of ​​the micro-electromechanical structure, and / or the detection area of ​​the cover layer (1) can be separated from the carrier layer (2) by a mechanical method.

9. The method according to claim 8, characterized in that When the detection area is formed in a non-functional area of ​​the micro-electromechanical structure, detecting the depth of the through hole (11) in the detection area includes: cutting the through hole (11) of the detection area and observing the cross section of the through hole (11); and / or The detection area is separated from the supporting layer (2) by the mechanical method, and the side of the detection area close to the supporting layer (2) is observed.

10. The method according to claim 9, characterized in that The step of separating the detection area from the carrier layer (2) by the mechanical method comprises: A plurality of separation grooves surrounding the detection area are formed on the surface of the cover layer (1), the separation grooves at least penetrate the cover layer (1), and a partial area of ​​the cover layer (1) surrounded by the plurality of separation grooves around each detection area forms a disassembly block; The disassembly block is disassembled along the separation groove to separate the disassembly block from the bearing layer (2) and the rest of the covering layer (1).

Images