MEMS device, manufacturing method thereof and electronic device

Abstract

The invention discloses an MEMS device, a manufacturing method thereof and an electronic device. The MEMS device comprises a semiconductor substrate, an interlayer dielectric layer, a top metal layer and a stop structure, wherein the top metal layer is formed in the interlayer dielectric layer, and at least part of the surface of the top metal layer is exposed out of the surface of the interlayer dielectric layer; an opening for exposing the interlayer dielectric layer below the top metal layer is formed in the top metal layer; the backstop structure is located in the opening, the bottom of the backstop structure is in contact connection with the interlayer dielectric layer below the top metal layer, and the top of the backstop structure protrudes out of the surface of the top metal layer. The supporting performance of the backstop structure can be improved, and the situation that the backstop structure collapses and deforms after being impacted, and consequently the blocking effect is lost is avoided.

Description

Technical Field

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

[0002] MEMS (Micro-Electro-Mechanical System) gyroscopes are miniature sensors used to detect rotational angular velocity or angle. When there is an input angular velocity or angle signal in the detection axis, the input angular velocity or angle signal can be inferred by detecting the movement of the movable mass block. With its small size and light weight, it is widely used in military and civilian fields.

[0003] The MEMS gyroscope has a movable mass block and a stopper structure. The stopper structure is a structure used to prevent excessive movement or displacement of the movable mass block in the MEMS gyroscope. The stopper structure can prevent the movable mass block from exceeding its range of motion during movement, causing collisions with functional devices, thereby causing damage or failure of the entire MEMS gyroscope device.

[0004] The stopper structure in the related art is prone to collapse and deform after being hit, thereby losing its blocking function. Summary of the invention

[0005] A series of simplified concepts are introduced in the Summary of the Invention, which will be further described in detail in the Detailed Description of the Invention. The Summary of the Invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0006] In response to the current problems, an embodiment of the present invention provides a MEMS device on one hand, which includes: a semiconductor substrate, an interlayer dielectric layer, a top metal layer and a stop structure; wherein the top metal layer is formed in the interlayer dielectric layer, and at least a portion of the surface of the top metal layer is exposed from the surface of the interlayer dielectric layer; an opening is formed in the top metal layer to expose the interlayer dielectric layer below the top metal layer; the stop structure is located in the opening, the bottom of the stop structure is in contact with the interlayer dielectric layer below the top metal layer, and the top of the stop structure protrudes from the surface of the top metal layer.

[0007] In one embodiment, the stop structure includes: a dielectric material body, and a conductive material layer located on a surface of a portion of the dielectric material body protruding above a surface of the top metal layer.

[0008] In one embodiment, the material of the dielectric body is silicon nitride or silicon oxide.

[0009] In one embodiment, the dielectric material body includes: a first dielectric body layer, and a second dielectric body layer located on the first dielectric body layer.

[0010] In one embodiment, the material of the first dielectric body layer is silicon oxide, and the material of the second dielectric body layer is silicon nitride.

[0011] In one embodiment, the conductive material layer also covers a portion of the surface of the top metal layer.

[0012] In one embodiment, the conductive material layer includes a titanium or titanium nitride layer.

[0013] In one implementation, the MEMS device includes a gyroscope.

[0014] A second aspect of an embodiment of the present invention provides a method for manufacturing a MEMS device, the manufacturing method comprising:

[0015] Providing a semiconductor substrate;

[0016] Forming an interlayer dielectric layer and a top metal layer in the interlayer dielectric layer on a semiconductor substrate, wherein at least a portion of the surface of the top metal layer is exposed on a surface of the interlayer dielectric layer;

[0017] Etching the surface of the top metal layer exposed from the interlayer dielectric layer to form a patterned opening exposing the interlayer dielectric layer below the top metal layer;

[0018] A patterned stop structure is formed in the patterned opening; the bottom of the stop structure is in contact with the interlayer dielectric layer below the top metal layer, and the top of the stop structure protrudes from the surface of the top metal layer.

[0019] In one embodiment, forming a patterned stop structure in a patterned opening includes:

[0020] forming a patterned body of dielectric material in the patterned opening, a portion of the body of dielectric material protruding above a surface of the top metal layer;

[0021] forming a conductive layer on the top metal layer, the conductive layer covering the patterned dielectric material body;

[0022] The conductive layer is etched to form a patterned conductive material layer; the conductive material layer covers the dielectric material body and a portion of the surface of the top metal layer.

[0023] In one embodiment, forming a patterned body of dielectric material in a patterned opening includes:

[0024] forming a dielectric material layer on the top metal layer, the dielectric material layer filling the patterned opening;

[0025] The dielectric material layer is etched to form a patterned dielectric material body.

[0026] In one embodiment, forming a patterned body of dielectric material in a patterned opening includes:

[0027] forming a first dielectric material layer on the top metal layer, the first dielectric material layer filling the opening;

[0028] forming a second dielectric material layer on the first dielectric material layer;

[0029] The second dielectric material layer and the first dielectric material layer are sequentially etched from top to bottom to form a patterned first dielectric main layer and a second dielectric main layer; the second dielectric main layer is located on the first dielectric main layer.

[0030] A third aspect of an embodiment of the present invention provides an electronic device, which includes the above MEMS device.

[0031] According to the MEMS device and its manufacturing method and electronic device provided by the present invention, an opening is formed in the top metal layer to expose the interlayer dielectric layer below it, so that the bottom of the stopper structure is in contact with the interlayer dielectric layer below the top metal layer, and the top of the stopper structure protrudes from the surface of the top metal layer. Since the stopper structure penetrates the top metal layer and then contacts and connects to the interlayer dielectric layer, the support of the stopper structure can be improved, and the stopper structure can be prevented from collapsing and deforming after being hit, thereby losing its blocking function. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The following drawings of the present invention are used to understand the present invention as part of the present invention. The embodiments of the present invention are shown in the drawings and the description thereof is used to explain the principle of the present invention.

[0033] In the attached figure:

[0034] Figures 1a to 1e Schematic cross-sectional views of MEMS devices according to different specific embodiments of the present invention are shown;

[0035] Figure 2 A flow chart showing a method for manufacturing a MEMS device according to an embodiment of the present invention;

[0036] Figure 3a to Figure 3m A cross-sectional schematic diagram showing each step in a method for manufacturing a MEMS device according to a specific embodiment of the present invention is shown. DETAILED DESCRIPTION

[0037] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0038] It should be understood that the present invention can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete and fully convey the scope of the present invention to those skilled in the art. In the accompanying drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0039] It should be understood that when an element or layer is referred to as being "on, adjacent to, connected to or coupled to other elements or layers, it may be directly on, adjacent to, connected to or coupled to other elements or layers, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on, directly adjacent to, directly connected to or directly coupled to other elements or layers, there may be no intervening elements or layers. It should be understood that, although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present invention, the first element, component, region, layer or part discussed below may be represented as a second element, component, region, layer or part.

[0040] Spatially relative terms such as "under," "below," "below," "under," "above," "above," etc., may be used herein for ease of description to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, the spatially relative terms are intended to include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "on" the other elements or features. Therefore, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be oriented otherwise (rotated 90 degrees or other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0041] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present invention. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0042] MEMS gyroscopes have a variety of applications. In some applications with strong shocks and vibrations, MEMS gyroscopes need to have corresponding shock resistance to ensure that MEMS devices do not fail or degrade in strong shock or vibration environments, and to achieve angular velocity measurement in harsh environments. Therefore, in addition to setting up a movable mass block in the MEMS gyroscope, a stop structure is also added. The stop structure is a structure used to prevent excessive movement or displacement of the movable mass block in the MEMS gyroscope. The stop structure can prevent the movable mass block from exceeding its range of motion during movement, causing collisions with functional devices, thereby causing damage or failure of the entire MEMS gyroscope device.

[0043] Related technologies: The stopper structure is generally set on the periphery of the movable mass block of the MEMS gyroscope. The stopper structure is usually grounded or suspended at a point, and there is a certain voltage difference with the movable mass block, which leads to the electrostatic force of mutual attraction between the stopper structure and the movable mass block, which is not conducive to the separation of the two to the initial position after the collision. Secondly, the stopper structure is usually set on the top metal layer, and its material is usually nitride. The support of the stopper structure is poor, and it is easy to collapse and deform after being hit, thus losing its blocking effect.

[0044] Therefore, in view of the existence of the above technical problems, an embodiment of the present invention proposes a MEMS device, referring to Figure 1a , Figure 1b , Figure 1d The MEMS device mainly includes: a semiconductor substrate 101, an interlayer dielectric layer 102, a top metal layer 103 and a stopper structure 105. The top metal layer 103 is formed in the interlayer dielectric layer 102, and at least part of the surface of the top metal layer 103 is exposed on the surface of the interlayer dielectric layer 102; an opening 104 is formed in the top metal layer 103 to expose the interlayer dielectric layer 102 below the top metal layer 103; the stopper structure 105 is located in the opening 104, the bottom of the stopper structure 105 is in contact with the interlayer dielectric layer 102 below the top metal layer 103, and the top of the stopper structure 105 protrudes from the surface of the top metal layer 103.

[0045] The above embodiment has the following beneficial effects: compared with the stopper structure 105 disposed on the top metal layer 103 in the related art, Figure 1a and Figure 1e In the above embodiment, an opening 104 is formed in the top metal layer 103 to expose the interlayer dielectric layer 102 thereunder, so that the bottom of the stopper structure 105 is in contact with the interlayer dielectric layer 102 below the top metal layer 103, and the top of the stopper structure 105 protrudes from the surface of the top metal layer 103, so as to limit the range of motion of the movable mass block 110. Since the stopper structure 105 in this embodiment penetrates the top metal layer 103 and then contacts and connects to the interlayer dielectric layer 102, after the stopper structure 105 is impacted, the stopper structure 105 can directly transmit the impact force to the interlayer dielectric layer 102, and the interlayer dielectric layer 102 bears the impact force. Since the material of the interlayer dielectric layer 102 is less prone to deformation than metal materials, the impact force conduction path formed by the stop structure 105→interlayer dielectric layer 102 can withstand a greater impact force without causing significant deformation, thereby improving the support of the stop structure 105, making the support of the stop structure 105 stronger, preventing the stop structure 105 from slipping or sinking into the top metal layer 103, and preventing the stop structure 105 from collapsing and deforming after being impacted, thereby losing its blocking effect.

[0046] Below, reference Figures 1a to 1e The MEMS device according to the embodiment of the present invention is described in detail.

[0047] In some embodiments, reference Figure 1a , the above-mentioned semiconductor substrate 101 can adopt any type of substrate. Exemplarily, the semiconductor substrate 101 can be a Si-containing semiconductor substrate. For example, the semiconductor substrate 101 can be a silicon substrate or a silicon-on-insulator (SOI). It should be noted that the term "Si-containing semiconductor substrate" refers to any semiconductor material containing at least silicon. Illustrative examples of Si-containing semiconductor materials that can be used as substrates include: Si, SiGe, SiC, SiGeC, silicon-on-insulator (SOI) or SiGe-on-insulator (SGOI), but are not limited thereto. Depending on the device being manufactured, the semiconductor substrate 101 can be undoped or doped. As an example, in the present embodiment, the semiconductor substrate 101 is made of single crystal silicon material.

[0048] In some embodiments, the interlayer dielectric layer 102 has a first surface and a second surface opposite to each other. Figure 1aThe lower surface of the interlayer dielectric layer 102 is the first surface, and the upper surface of the interlayer dielectric layer 102 is the second surface. The interlayer dielectric layer 102 may be a metal interlayer dielectric layer. Preferably, the interlayer dielectric layer 102 is formed of a low dielectric constant dielectric material, such as fluorosilicate glass (FSG), silicon oxide, carbon-containing material, porous-like material, or the like.

[0049] For example, the interlayer dielectric layer 102 may be a silicon oxide layer, including a doped or undoped silicon oxide material layer formed by a thermal chemical vapor deposition (thermal CVD) manufacturing process or a high density plasma (HDP) manufacturing process, such as undoped silicon glass (USG), phosphosilicate glass (PSG) or borophosphosilicate glass (BPSG). In addition, the interlayer dielectric layer 102 may also be spin-on-glass (SOG) doped with boron or phosphorus, tetraethoxysilane doped with phosphorus (PTEOS) or tetraethoxysilane doped with boron (BTEOS).

[0050] The interlayer dielectric layer 102 may be made of, for example, SiO2 (silicon dioxide), fluorocarbon (CF), carbon-doped silicon oxide (SiOC), or silicon carbonitride (SiCN). Alternatively, a film having a SiCN film formed on a fluorocarbon (CF) may be used. Fluorocarbons have fluorine (F) and carbon (C) as their main components. Fluorocarbons may also be made of materials having an amorphous (non-crystalline) structure. The interlayer dielectric layer 102 may also be made of a porous structure such as carbon-doped silicon oxide (SiOC).

[0051] It should be noted that the method in which at least part of the surface of the above-mentioned top metal layer 103 is exposed on the surface of the interlayer dielectric layer 102 can be: a top metal layer 103 is arranged in the interlayer dielectric layer 102, and a window is opened in a partial area of ​​the interlayer dielectric layer 102, so that part or all of the surface of the top metal layer 103 is exposed on the surface of the interlayer dielectric layer 102.

[0052] In some embodiments, the material of the top metal layer 103 can be any conductive layer structure. Exemplarily, the material of the top metal layer 103 can use gold (Au), silver (Ag), platinum (Pt), palladium (Pd), etc. In some embodiments, the material of the top metal layer 103 can use a conductive material including a transparent metal oxide. As a transparent conductive material, indium tin oxide (ITO), zinc oxide (ZnO), indium zinc oxide (IZO), gallium-doped zinc oxide (GZO), or other light-transmitting conductive oxide materials can be used. In addition, indium tin oxide containing silicon dioxide or indium oxide containing silicon dioxide can be used, in which 2 to 20 weight % of zinc oxide (ZnO) is also mixed. The above materials can be formed by droplet discharge method, evaporation method, sputtering method, CVD method, spin coating method, or printing such as screen printing or gravure printing. For example, Ag can be formed by droplet discharge method, and Al can be formed by evaporation method.

[0053] As long as the material is conductive, the material of the top metal layer 103 is not particularly limited. Conductive materials and metal compounds having one or more selected from Ag, Au, Cu, Pd, Cr, Mo, Ti, Ta, W and Al can be used. Exemplarily, the material of the top metal layer 103 can be Ti or TiN. In addition, known conductive polymers whose conductivity is increased by doping, such as conductive polyaniline, conductive polypyrrole, conductive polythiophene, polyethylenedioxythiophene (PEDOT), polystyrene sulfonate (PSS), etc. can be used.

[0054] In some embodiments, reference Figure 1a , an interconnect structure is formed in the interlayer dielectric layer 102, and the interconnect structure includes a top metal layer 103. Of course, the interconnect structure may also include other metal layers. Figure 1a The interconnect structure further includes a bottom metal layer located below the top metal layer 103 and conductive plugs connected between different metal layers.

[0055] In some embodiments, reference Figure 1b The shape of the opening 104 can be any shape such as but not limited to circular, rectangular, waist-shaped, etc., which is specifically related to the shape of the stop structure 105.

[0056] There are many ways to form the stop structure 105, some of which are exemplified below.

[0057] In some embodiments, reference Figure 1c and Figure 1d The stopping structure 105 may include: a dielectric material body, and a conductive material layer 108 located on the surface of a portion of the dielectric material body protruding from the surface of the top metal layer 103 .

[0058] Specifically, in the above embodiments, reference Figure 1d The stop structure 105 includes two types of materials, wherein the main body is a dielectric material main body, that is, the main body part is composed of a dielectric material. Figure 1c The dielectric material body is located in the opening 104, and the dielectric material body extends downward into the opening 104, and its bottom is in contact with the interlayer dielectric layer 102 below the top metal layer 103. The thickness of the dielectric material body is also higher than the depth of the opening 104, so that the top of the dielectric material body protrudes from the top metal layer 103 and is away from the surface of the semiconductor substrate 101. Figure 1d , wherein the conductive material layer 108 is located on the surface of the dielectric material body that protrudes from the surface of the top metal layer 103. Exemplarily, the conductive material layer 108 can be arranged on the upper surface and at least a portion of the side surface of the dielectric material body.

[0059] The above embodiment has the following beneficial effects: by using the dielectric material body as the main part of the stopper structure 105, the dielectric material body is in contact with the interlayer dielectric layer 102 below the top metal layer, and the properties of both being dielectric materials are used to improve the reliability and stability of the contact connection between the two, thereby improving the anti-slip effect of the stopper structure 105, and also improving the rigidity of the stopper structure 105, preventing the stopper structure 105 from deforming and collapsing and thus losing the blocking function. In addition, a conductive material layer 108 is provided on the surface of the portion of the dielectric material body protruding from the surface of the top metal layer 103, so that the stopper structure 105 and the movable mass block 110 are at the same potential, so that there is no voltage difference between the stopper structure 105 and the movable mass block 110, and the equipotential connection between the stopper structure 105 and the movable mass block 110 is achieved, and the electrostatic force of mutual attraction between the stopper structure 105 and the movable mass block 110 is avoided, so that the two are separated to the initial position after collision, and the problem that the movable mass block 110 cannot be restored due to electrostatic adsorption is solved.

[0060] In some embodiments, the material of the dielectric material body may be selected in the same manner as the material of the interlayer dielectric layer 102 described above.

[0061] Exemplarily, the material of the dielectric material body may be silicon nitride or silicon oxide, that is, the dielectric material body is prepared from a single material, thereby simplifying the preparation process of the dielectric material body.

[0062] Specifically, the material of the dielectric material body can be silicon nitride. By selecting silicon nitride with higher hardness as the material for preparing the dielectric material body, the dielectric material body has higher hardness, can withstand greater impact force, and is not easily broken, thereby improving the impact resistance of the stop structure 105.

[0063] The material of the dielectric material body can also be silicon oxide. Generally, the material of the interlayer dielectric layer 102 is also silicon oxide, so that the dielectric material body and the interlayer dielectric layer 102 can be made of the same material, thereby utilizing the feature of easy bonding of the same materials to improve the contact connection reliability between the dielectric material body and the interlayer dielectric layer 102.

[0064] In some embodiments, the dielectric material body may be formed by stacking layers composed of different materials to achieve corresponding functions.

[0065] For example, reference Figure 1c The dielectric material body may include: a first dielectric body layer 106, and a second dielectric body layer 107 located on the first dielectric body layer 106. The specific configuration may be in various ways.

[0066] Exemplarily, the first dielectric body layer 106 may be filled in the opening 104 so that the bottom of the first dielectric body layer 106 contacts and connects the interlayer dielectric layer 102 below the top metal layer 103. The first dielectric body layer 106 also protrudes from the surface of the top metal layer 103 away from the semiconductor substrate 101, that is, the thickness of the first dielectric body layer 106 is greater than the depth of the opening 104.

[0067] The above embodiment has the following beneficial effects: by using a dielectric material body composed of two dielectric layers, the first dielectric body layer 106 can be made of a material with good adhesion to the interlayer dielectric layer 102, thereby improving the contact connection reliability between the dielectric material body and the interlayer dielectric layer 102. The second dielectric body layer 107 can achieve other functions.

[0068] The material of the first dielectric main layer 106 may be selected in a variety of ways, and some implementations are exemplarily described below.

[0069] In some embodiments, the material of the first dielectric main layer 106 is silicon oxide. Generally, the material of the interlayer dielectric layer 102 is also silicon oxide, so that the first dielectric main layer 106 and the interlayer dielectric layer 102 can be made of the same material, thereby utilizing the feature of easy adhesion of the same material to improve the contact connection reliability between the first dielectric main layer 106 and the interlayer dielectric layer 102.

[0070] In some embodiments, reference Figure 1cThe first dielectric main layer 106 can be made of the same material as the interlayer dielectric layer 102 located below and in contact with it, so as to improve the contact connection reliability between the first dielectric main layer 106 and the interlayer dielectric layer 102 by utilizing the feature of easy bonding of the same materials. It should be noted that the interlayer dielectric layer 102 is not limited to being composed of one layer of material, and can be composed of at least two layers of material. In this embodiment, it is only necessary that the first dielectric main layer 106 can be made of the same material as the interlayer dielectric layer 102 located below and in contact with it.

[0071] In some embodiments, the materials of the interlayer dielectric layer 102 and the first dielectric body layer 106 may both be silicon oxide to improve the connection reliability between the two.

[0072] The material of the second dielectric main layer 107 can be selected in a variety of ways, and some implementations are exemplarily introduced below.

[0073] In some embodiments, the material of the second dielectric main layer 107 can be silicon nitride. The impact point between the movable mass block 110 and the stop structure 105 is usually located on the upper surface of the stop structure 105, so that there is a stress concentration phenomenon near the impact point between the upper surface of the stop structure 105 and the movable mass block 110 during the impact, resulting in greater stress near the impact point. In the above embodiment, by selecting a second dielectric main layer 107 with higher hardness to be stacked on the upper surface of the first dielectric main layer 106, the material main body near the impact point is the second dielectric main layer 107 with higher hardness, which can withstand greater impact force and is not easy to be broken, and can also protect the first dielectric main layer 106, thereby improving the impact resistance of the stop structure 105.

[0074] In some embodiments, reference Figure 1d The conductive material layer 108 also covers part of the surface of the top metal layer 103, that is, the conductive material layer 108 also extends to cover the surface of the top metal layer 103 facing away from the semiconductor substrate 101, so that the conductive material layer 108 is electrically connected to the top metal layer 103, so that the potential on the surface of the stop structure 105 can be adjusted through the interconnection structure in the interlayer dielectric layer 102, so that there is no voltage difference between the stop structure 105 and the movable mass block 110, and the equipotential connection between the stop structure 105 and the movable mass block 110 is achieved, avoiding the generation of mutually attractive electrostatic force between the stop structure 105 and the movable mass block 110, which is conducive to the separation of the two to the initial position after collision, and solves the problem that the movable mass block 110 cannot be restored due to electrostatic adsorption.

[0075] Specifically, refer to Figure 1dThe conductive material layer 108 covers the upper surface and sidewalls of the dielectric material body, and the conductive material layer 108 also extends to cover a portion of the surface of the top metal layer 103 facing away from the semiconductor substrate 101, thereby achieving electrical connection between the conductive material layer 108 and the top metal layer 103.

[0076] As for the material of the conductive material layer 108 , any conductive material may be selected, and some exemplary methods are introduced as follows.

[0077] Exemplarily, the conductive material layer 108 may include a titanium or titanium nitride layer, that is, the raw material for preparing the conductive material layer 108 is titanium or titanium nitride. Titanium or titanium nitride has better hardness and rigidity than aluminum, a raw material commonly used to prepare metal layers, so the titanium or titanium nitride layer with higher hardness and rigidity is used as the conductive material layer 108, thereby improving the hardness of the surface of the stop structure 105. In this way, the stop structure 105 can withstand a greater impact force at the impact point with the movable mass block 110 without being broken, thereby improving the overall impact resistance of the stop structure 105.

[0078] In some embodiments, the MEMS device may further include a gyroscope, and the movable mass block 110 may be a suspended interdigitated finger structure in the gyroscope, thereby enabling the MEMS device to achieve the function of measuring angular velocity or angular acceleration.

[0079] Regarding the structure of the movable mass block 110, any mass block that can move relative to the semiconductor substrate 101 can be used, so that during the movement of the MEMS device, the velocity or acceleration can be measured by changing the positional relationship between the movable mass block 110 and the semiconductor substrate 101. Exemplarily, the movable mass block 110 can adopt a suspended interdigitated finger structure.

[0080] In one embodiment, reference Figure 1e , the MEMS device further includes: a cavity 109 and a movable mass block 110; wherein the cavity 109 is formed on the side of the top metal layer 103 away from the semiconductor substrate 101; the movable mass block 110 is disposed in the cavity 109, and the stop structure 105 is used to block the movement range of the movable mass block 110. The above embodiment has the following beneficial effects: by forming the cavity 109 for accommodating the movable mass block 110, and the stop structure 105 also extends into the cavity 109 to block the movement range of the movable mass block 110, the MEMS device can use the inertia of the movable mass block 110 to measure indicators such as but not limited to velocity and acceleration.

[0081] There are many ways to form the cavity 109 on the second surface of the interlayer dielectric layer 102 .

[0082] Exemplary, reference Figure 1eThe aforementioned semiconductor substrate 101 may be a first semiconductor substrate. A second semiconductor substrate 111 is provided, and a cavity 109 and a movable mass block 110 are formed on the second semiconductor substrate 111 by, for example, but not limited to, an etching process, and then the first semiconductor substrate and the second semiconductor substrate 111 are bonded, so that the stop structure 105 can extend into the cavity 109 to block the movement range of the movable mass block 110.

[0083] Embodiment 2

[0084] The present invention also provides a method for manufacturing a MEMS device, referring to Figure 2 , which mainly includes the following steps:

[0085] In step S201, a semiconductor substrate is provided;

[0086] In step S202, an interlayer dielectric layer and a top metal layer located in the interlayer dielectric layer are formed on a semiconductor substrate, and at least a portion of the surface of the top metal layer is exposed on the surface of the interlayer dielectric layer;

[0087] In step S203, the surface of the top metal layer exposed above the interlayer dielectric layer is etched to form a patterned opening exposing the interlayer dielectric layer below the top metal layer;

[0088] In step S204, a patterned stop structure is formed in the patterned opening; the bottom of the stop structure is in contact with the interlayer dielectric layer below the top metal layer, and the top of the stop structure protrudes from the surface of the top metal layer.

[0089] Below, reference Figure 3a to Figure 3m The manufacturing method of the MEMS device according to the embodiment of the present invention is described in detail, wherein: Figure 3a to Figure 3m The cross-sectional schematic diagram of the MEMS device obtained by implementing each step of the manufacturing method of the MEMS device according to an embodiment of the present invention is shown. It is worth mentioning that in order to avoid repetition, the same components and structures as those in the above-mentioned embodiment 1 are only briefly described, and their specific explanations and descriptions can refer to the description in the embodiment 1.

[0090] first, Figure 3a , provide a semiconductor substrate 301. The semiconductor substrate 301 can be any type of substrate, and the details are described in the above part, which will not be repeated here.

[0091] Next, refer to Figure 3h An interlayer dielectric layer 302 and a top metal layer 308 located in the interlayer dielectric layer 302 are formed on the semiconductor substrate 301 , and at least a portion of the surface of the top metal layer 308 is exposed on the surface of the interlayer dielectric layer 302 .

[0092] Exemplary, reference Figure 3h An interlayer dielectric layer 302 is formed on a semiconductor substrate 301. An interconnection structure is formed in the interlayer dielectric layer 302. The interconnection structure includes the top metal layer 308 described above, and may also include other metal layers or conductive plugs. The specific process may adopt various semiconductor manufacturing processes such as, but not limited to, deposition, etching, and planarization.

[0093] There are many ways to form the interlayer dielectric layer 302 on the semiconductor substrate 301 and the top metal layer 308 in the interlayer dielectric layer 302. Figure 3a-3h A method is introduced as an example.

[0094] like Figure 3a As shown, an interlayer dielectric layer 302 is formed on a semiconductor substrate 301. Figure 3b , a patterned first contact hole 303 is formed by etching on the interlayer dielectric layer 302. Then, referring to Figure 3c , depositing a bottom metal material layer 304, and allowing the bottom metal material layer 304 to fill the first contact hole 303, thereby forming a first conductive plug in the first contact hole 303. Figure 3d , the bottom metal material layer 304 is patterned to form a bottom metal layer 305, and the bottom metal layer 305 is electrically connected to the semiconductor substrate 301 through a first conductive plug. Figure 3e , depositing an interlayer dielectric layer 302 on the bottom metal layer 305. Then, referring to Figure 3f , a patterned second contact hole 306 is formed by etching on the newly formed interlayer dielectric layer 302. Then, referring to Figure 3g , depositing a top metal material layer 307, and allowing the top metal material layer 307 to fill the second contact hole 306, thereby forming a second conductive plug in the second contact hole 306. Figure 3h The top metal material layer is patterned to form a top metal layer 308 , and the top metal layer 308 is electrically connected to the bottom metal layer 305 through the second conductive plug. At least a portion of the surface of the top metal layer 308 is exposed on the surface of the interlayer dielectric layer 302 .

[0095] Next, continue to refer to Figure 3h , the surface of the top metal layer 308 exposed on the interlayer dielectric layer 302 is etched to form a patterned opening 309 exposing the interlayer dielectric layer 302 below the top metal layer 308 .

[0096] Exemplary, reference Figure 3hThe process of etching the top metal layer 308 to form an opening in the top metal layer 308 to expose the interlayer dielectric layer 302 below the top metal layer 308 may be a wet etching process, a dry etching process, etc. During the etching process, a patterned hard mask may be deposited on the top metal layer 308 before etching to protect the surface of the top metal layer 308 from being damaged by etching back splash.

[0097] Next, refer to Figure 3m , a patterned stopping structure is formed in the patterned opening 309 ; the bottom of the stopping structure is in contact with the interlayer dielectric layer 302 below the top metal layer 308 , and the top of the stopping structure protrudes from the surface of the top metal layer 308 .

[0098] There are many ways to form the stop structure in the opening 309 , some of which are exemplarily described below.

[0099] Exemplarily, forming a patterned stop structure in the patterned opening 309 may include:

[0100] refer to Figure 3i-3k , forming a patterned dielectric material body in the patterned opening 309 , a portion of the dielectric material body protruding from a surface of the top metal layer 308 ;

[0101] refer to Figure 3l , forming a conductive layer 314 on the top metal layer 308, the conductive layer 314 covering the patterned dielectric material body;

[0102] refer to Figure 3m , the conductive layer 314 is etched to form a patterned conductive material layer 315 ; the conductive material layer 315 covers the dielectric material body and a portion of the surface of the top metal layer 308 .

[0103] There are many ways to form the patterned dielectric material body in the patterned opening 309 , some of which are exemplarily described below.

[0104] Illustratively, forming a patterned dielectric material body in the patterned opening 309 may include:

[0105] refer to Figure 3i-3j , forming a dielectric material layer on the top metal layer 308 , the dielectric material layer filling the patterned opening 309 ;

[0106] refer to Figure 3k , etching the dielectric material layer to form a patterned dielectric material body.

[0107] Exemplarily, forming a stop structure in the opening 309 may include:

[0108] refer to Figure 3i-3j , forming a dielectric material layer to fill the opening 309 and cover the surface of the top metal layer 308 facing away from the semiconductor substrate 301;

[0109] refer to Figure 3k , etching the dielectric material layer to form a dielectric material body; wherein the dielectric material body is filled in the opening 309 to contact the interlayer dielectric layer 302 below the top metal layer 308, and the dielectric material body also protrudes from the surface of the top metal layer 308.

[0110] Specifically, a dielectric material layer is first deposited on the surface of the top metal layer 308 facing away from the semiconductor substrate 301, and the dielectric material layer fills the opening 309 and covers the surface of the top metal layer 308 facing away from the semiconductor substrate 301. Thereafter, the dielectric material layer is etched to form a patterned dielectric material body, and the specific etching process may be, for example, but not limited to, a photolithography process, a wet etching process, a dry etching process, and the like.

[0111] Of course, in addition to the above-described method, other methods may be used to form the patterned dielectric material body in the patterned opening 309 .

[0112] For example, forming a patterned dielectric material body in the patterned opening 309 may further include:

[0113] refer to Figure 3i , forming a first dielectric material layer 310 on the top metal layer 308 , wherein the first dielectric material layer 310 fills the opening 309 ;

[0114] refer to Figure 3j , forming a second dielectric material layer 311 on the first dielectric material layer 310;

[0115] refer to Figure 3k , the second dielectric material layer 311 and the first dielectric material layer 310 are etched from top to bottom in sequence to form a patterned first dielectric main layer 312 and a second dielectric main layer 313 ; the second dielectric main layer 313 is located on the first dielectric main layer 312 .

[0116] That is, the dielectric material layer in the above embodiment is composed of a first dielectric material layer 310 and a second dielectric material layer 311. When the dielectric material layer is deposited on the surface of the top metal layer 308 away from the semiconductor substrate 301, refer to Figure 3i , a first dielectric material layer 310 may be deposited on the surface of the top metal layer 308 facing away from the semiconductor substrate 301 , the first dielectric material layer 310 fills the opening 309 and covers the surface of the top metal layer 308 facing away from the semiconductor substrate 301 . Then, a second dielectric material layer 311 may be deposited on the first dielectric material layer 310 .

[0117] The etching of the dielectric material layer is specifically to etch the second dielectric material layer 311 and the first dielectric material layer 310 from top to bottom in order to form a patterned first dielectric main layer 312 and a second dielectric main layer 313; the second dielectric main layer 313 is located on the first dielectric main layer 312, and the stacked first dielectric main layer 312 and the second dielectric main layer 313 together form a dielectric material main body. Specifically, the second dielectric material layer 311 is etched to form the second dielectric main layer 313, and then the first dielectric material layer 310 is further etched to form the first dielectric main layer 312, so as to manufacture a dielectric material main body including the first dielectric main layer 312 and the second dielectric main layer 313.

[0118] Exemplarily, forming a stop structure in the opening 309 may further include: Figure 3l , forming a conductive layer 314 to cover the dielectric material body and the surface of the top metal layer 308; etching the conductive layer 314 to form a conductive material layer 315 covering the dielectric material body, and the conductive material layer 315 also covers a portion of the surface of the top metal layer 308. The conductive layer 314 may be etched by, for example, but not limited to, a wet etching process, a dry etching process, etc., to form a patterned conductive material layer 315 covering the dielectric material body.

[0119] At this point, the process steps implemented in the method for manufacturing a MEMS device according to an embodiment of the present invention have been completed. It can be understood that the method for manufacturing a MEMS device in this embodiment not only includes the above steps, but may also include other necessary steps before, during or after the above steps, which are all included in the scope of the manufacturing method of this embodiment.

[0120] According to the manufacturing method of the MEMS device provided by the present invention, an opening 309 is formed in the top metal layer 308 to expose the interlayer dielectric layer 302 thereunder, so that the bottom of the stopper structure is in contact with and connected to the interlayer dielectric layer 302 below the top metal layer 308, and the top of the stopper structure protrudes from the surface of the top metal layer 308. Since the stopper structure penetrates the top metal layer 308 and then contacts and connects to the interlayer dielectric layer 302, the support of the stopper structure can be improved, and the stopper structure can be prevented from collapsing and deforming after being hit, thereby losing its blocking function.

[0121] Embodiment 3

[0122] Another embodiment of the present invention provides an electronic device, which includes the aforementioned MEMS device, and the MEMS device is manufactured according to the aforementioned method.

[0123] The electronic device of this embodiment can be any electronic product or device such as a mobile phone, a tablet computer, a laptop computer, a netbook, a game console, a television, a VCD, a DVD, a navigator, a digital photo frame, a camera, a video camera, a voice recorder, an MP3, an MP4, a PSP, etc., or any intermediate product including a circuit. The electronic device of the embodiment of the present invention has better performance due to the use of the above-mentioned MEMS device.

[0124] The present invention has been described by the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present invention is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of the protection claimed by the present invention. The protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A MEMS device, characterized in that: include: Semiconductor substrate; an interlayer dielectric layer formed on the semiconductor substrate; A top metal layer is formed in the interlayer dielectric layer, and at least a portion of the surface of the top metal layer is exposed on the surface of the interlayer dielectric layer; an opening is formed in the top metal layer to expose the interlayer dielectric layer below the top metal layer; A stopping structure is located in the opening, wherein the bottom of the stopping structure is in contact with the interlayer dielectric layer below the top metal layer, and the top of the stopping structure protrudes from the surface of the top metal layer.

2. The MEMS device according to claim 1, characterized in that The stop structure comprises: A dielectric material body, and a conductive material layer located on a surface of a portion of the dielectric material body protruding above a surface of the top metal layer.

3. The MEMS device according to claim 2, characterized in that The main body of the dielectric material is made of silicon nitride or silicon oxide.

4. The MEMS device according to claim 2, characterized in that The dielectric material body comprises: A first dielectric body layer, and a second dielectric body layer located on the first dielectric body layer.

5. The MEMS device according to claim 4, characterized in that The material of the first dielectric main layer is silicon oxide, and the material of the second dielectric main layer is silicon nitride.

6. The MEMS device according to claim 2, characterized in that: The conductive material layer also covers a portion of the surface of the top metal layer.

7. The MEMS device according to claim 2, characterized in that: The conductive material layer includes a titanium or titanium nitride layer.

8. The MEMS device according to claim 1, characterized in that: The MEMS device includes a gyroscope.

9. A method for manufacturing a MEMS device, characterized in that: include: Providing a semiconductor substrate; Forming an interlayer dielectric layer and a top metal layer in the interlayer dielectric layer on the semiconductor substrate, wherein at least a portion of the surface of the top metal layer is exposed on the surface of the interlayer dielectric layer; Etching the surface of the top metal layer exposed from the interlayer dielectric layer to form a patterned opening exposing the interlayer dielectric layer below the top metal layer; A patterned stop structure is formed in the patterned opening; the bottom of the stop structure is in contact with the interlayer dielectric layer below the top metal layer, and the top of the stop structure protrudes from the surface of the top metal layer.

10. The manufacturing method according to claim 9, characterized in that: The forming of a patterned stop structure in the patterned opening comprises: forming a patterned body of dielectric material in the patterned opening, a portion of the body of dielectric material protruding above a surface of the top metal layer; forming a conductive layer on the top metal layer, the conductive layer covering the patterned dielectric material body; The conductive layer is etched to form a patterned conductive material layer; the conductive material layer covers the dielectric material body and a portion of the surface of the top metal layer.

11. The manufacturing method according to claim 10, characterized in that: The forming of a patterned dielectric material body in the patterned opening comprises: forming a dielectric material layer on the top metal layer, the dielectric material layer filling the patterned opening; The dielectric material layer is etched to form the patterned dielectric material body.

12. The manufacturing method according to claim 10, characterized in that: The forming of a patterned dielectric material body in the patterned opening comprises: forming a first dielectric material layer on the top metal layer, wherein the first dielectric material layer fills the opening; forming a second dielectric material layer on the first dielectric material layer; The second dielectric material layer and the first dielectric material layer are sequentially etched from top to bottom to form a patterned first dielectric main layer and a second dielectric main layer; the second dielectric main layer is located on the first dielectric main layer.

13. An electronic device, characterized in that: The electronic device comprises the MEMS device according to any one of claims 1 to 8.

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