Microelectromechanical device and method of manufacturing the same

Abstract

A microelectromechanical device includes a support substrate, a cavity, a stop member, a microelectromechanical structure, and a bonding dielectric layer. The cavity is located in a top surface of the support substrate, and the stop member is adjacent to the cavity with a top surface of the stop member at the same height as the top surface of the support substrate. The microelectromechanical structure is disposed on the support substrate, and includes a mass disposed directly above the stop member and a cantilever disposed directly above the cavity. The bonding dielectric layer is disposed between the top surface of the support substrate and a bottom surface of the microelectromechanical structure.

Description

Technical Field

[0001] This invention relates to microelectromechanical systems (MEMS) devices, particularly microelectromechanical systems comprising a stop component corresponding to a mass block, and a method for manufacturing the same. Background Technology

[0002] In recent years, micro-electro-mechanical systems (MEMS) devices have become a achievable technology, and their applications in the microelectronics industry have received increasing attention. MEMS devices include components such as gyroscopes, accelerometers, resonators, and pressure sensors. MEMS devices can include a sense mass and beams supporting it. The sense mass and beams are typically housed in a sealed chamber and suspended above a cavity on a semiconductor substrate. During operation, the sense mass and beams can shift or vibrate within the sealed chamber. Micromachining processes are commonly used to form the beams and sense mass, selectively etching away portions of the thinned device substrate. However, during the etching of the thinned substrate, it is difficult to simultaneously form both a thin support beam with a uniform pattern (e.g., uniform width / spacing) and a heavy sense mass. Often, the pattern of the thinner support beam is non-uniform, leading to decreased production yield and reliability of the MEMS device. Therefore, the industry urgently needs improved MEMS devices and their manufacturing methods to overcome the above problems. Summary of the Invention

[0003] In view of this, embodiments of the present invention provide an improved microelectromechanical system (MEMS) device and a method for manufacturing the same. This MEMS device includes a cantilever beam with a uniform pattern, and no striations are generated on the sidewalls of the cantilever beam. Furthermore, the MEMS device includes a precisely dimensionally controlled gap between a proof mass and a stopper. Embodiments of the present invention can improve the reliability and production yield of the MEMS device, and increase the flexibility of product adjustments.

[0004] According to an embodiment of the present invention, a microelectromechanical system (MEMS) device is provided, including a support substrate, a cavity, a stop component, a microelectromechanical structure, and a bonding dielectric layer. The cavity is located on the top surface of the support substrate, and the stop component is adjacent to the cavity, wherein the top surface of the stop component is at the same height as the top surface of the support substrate. The microelectromechanical structure is disposed on the support substrate, wherein the microelectromechanical structure includes a mass block and a cantilever component, the mass block is disposed directly above the stop component, the cantilever component is disposed directly above the cavity, and the bonding dielectric layer is disposed between the top surface of the support substrate and the bottom surface of the microelectromechanical structure.

[0005] According to an embodiment of the present invention, a method for manufacturing a microelectromechanical system (MEMS) device is provided, comprising the following steps: providing a support substrate and etching the support substrate to form a cavity and a stop member on the top surface of the support substrate; forming a bonding dielectric layer on the top surface of the support substrate and the top surface of the stop member; disposing a microelectromechanical device layer on the bonding dielectric layer, wherein the microelectromechanical device layer is bonded to the stop member and the support substrate; patterning the microelectromechanical device layer to form a microelectromechanical structure, wherein the microelectromechanical structure includes a mass block and a cantilever member, the mass block being bonded to the stop member, and the cantilever member being formed directly above the cavity; removing a portion of the bonding dielectric layer located between the stop member and the mass block to form a gap between the stop member and the mass block.

[0006] To make the features of the present invention clear and easy to understand, embodiments are provided below, along with accompanying drawings, for detailed explanation. Attached Figure Description

[0007] To facilitate understanding of the following text, reference should be made to the accompanying drawings and detailed descriptions while reading this invention. Specific embodiments of the invention are explained in detail through reference to the corresponding drawings, which illustrate the working principles of these embodiments. Furthermore, for clarity, features in the drawings may not be drawn to scale, and therefore the dimensions of some features in certain drawings may be intentionally enlarged or reduced. Figure 1 This is a top view schematic diagram of a microelectromechanical (MEMS) device illustrated according to some embodiments of the present invention. Figure 2A and Figure 2B This is a cross-sectional schematic diagram of a MEMS device illustrated according to some embodiments of the present invention. Figure 3A and Figure 3B This is a cross-sectional schematic diagram of a MEMS device illustrated according to some other embodiments of the present invention. Figure 4 This is a cross-sectional schematic diagram illustrating the structure of a MEMS device bonded to a CMOS wafer according to an embodiment of the present invention. Figure 5 , Figure 6 and Figure 7 This is a cross-sectional schematic diagram illustrating some stages of a method for manufacturing a MEMS device according to an embodiment of the present invention. Figure 8 , Figure 9 and Figure 10 This is a cross-sectional schematic diagram illustrating some stages of a method for manufacturing a MEMS device according to another embodiment of the present invention. The annotations in the attached figures are explained as follows: 100, 100A, 100B, 100C, 100D…MEMS devices 101…Support substrate 103…stop component 105…alignment mark 107…Cavity 109…gap 111…bonded dielectric layer 113…Dielectric layer 120…MEMS Structure 121… mass block 122…MEMS wafer 123…Cantilever components 124…MEMS Device Layer 125…Suspension comb-shaped component 127…Fixed part 127-1…comb-like portion 127-2… Main Part 128…protrusion 129… conductor 130…CMOS wafer 131… Semiconductor substrate 132…Interconnection Layer D1…Depth H1…height 200… structure TS…dashed line Thicknesses T1, T2... Steps S301, S303, S305, S306, S307, S309, S311, S313… Detailed Implementation

[0008] This invention provides several different embodiments that can be used to implement different features of the invention. For the sake of simplicity, examples of specific components and arrangements are also described. These embodiments are provided for illustrative purposes only and are not intended to be limiting. For example, the following description of "a first feature forming on or above a second feature" can mean "the first feature and the second feature are in direct contact" or "there are other features between the first feature and the second feature," such that the first feature and the second feature are not in direct contact. Furthermore, various embodiments of this invention may use repeated reference numerals and / or textual annotations. The use of these repeated reference numerals and annotations is for the purpose of making the description more concise and clear, and is not intended to indicate any correlation between different embodiments and / or configurations.

[0009] Furthermore, for the spatially related descriptive terms mentioned in this invention, such as "below," "low," "down," "above," "above," "upper," "top," "bottom," and similar terms, for ease of description, their use is to describe the relative relationship between one element or feature and another (or more) element or feature in the accompanying drawings. In addition to the orientation shown in the drawings, these spatially related terms are also used to describe the possible orientations of the semiconductor device during use and operation. As the orientation of the semiconductor device varies (rotation of 90 degrees or other orientations), the spatially related descriptions used to describe its orientation should be interpreted in a similar manner.

[0010] Although the present invention uses terms such as first, second, third, etc., to describe various elements, components, regions, layers, and / or sections, it should be understood that these elements, components, regions, layers, and / or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, and / or section from another element, component, region, layer, and / or section, and do not in themselves imply or represent any prior ordinal number of the element, nor do they represent the arrangement order of one element with another, or the order of manufacturing methods. Therefore, without departing from the scope of the specific embodiments of the present invention, the first element, component, region, layer, or section discussed below may also be represented as a second element, component, region, layer, or section.

[0011] The terms "about" or "substantially" as used in this invention generally mean within 20% of a given value or range, preferably within 10%, and even more preferably within 5%, or within 3%, or within 2%, or within 1%, or within 0.5%. It should be noted that the quantities provided in the specification are approximate quantities; that is, the meaning of "about" or "substantially" may be implied even without specific specification.

[0012] Although the invention is described below by way of specific embodiments, the inventive principles of the invention can also be applied to other embodiments. Furthermore, in order to avoid obscuring the spirit of the invention, certain details have been omitted; these omitted details fall within the scope of knowledge of those skilled in the art.

[0013] This invention relates to a microelectromechanical system (MEMS) device and its manufacturing method. The MEMS device includes an inertial measurement unit (IMU), such as an accelerometer or gyroscope. A support substrate for the MEMS device includes a cavity and a stop component on the top surface of the support substrate. The MEMS structure of the MEMS device includes a mass block and a cantilever component connected to the mass block. The mass block and the cantilever component are formed by patterning the MEMS device layers through an etching process. During etching, the mass block is bonded to the stop component via a bonding dielectric layer and is supported by the stop component, thereby preventing the mass block from moving downwards and thus preventing movement of the cantilever component during the patterning of the MEMS device layers. Therefore, the cantilever component of the MEMS device has a uniform pattern and avoids streaks forming on the sidewalls of the cantilever component. Subsequently, a portion of the bonding dielectric layer between the mass block and the stop component is removed to obtain a gap between the mass block and the stop component of the MEMS device, and the size of this gap is precisely controlled. Therefore, embodiments of this invention can improve the reliability and production yield of MEMS devices and increase the flexibility of product adjustments for MEMS devices.

[0014] Figure 1 This is a top view schematic diagram of a MEMS device 100 according to some embodiments of the present invention. Figure 2A and Figure 2B It is illustrated along some embodiments of the present invention. Figure 1 The cross-sectional view of MEMS devices 100A and 100B of TT is shown in the figure. (See also...) Figure 1 The MEMS device 100 includes a MEMS structure 120 disposed on a support substrate 101, wherein the top view of the stop component 103 and the cavity 107 of the MEMS device 100 is shown in... Figure 1 The MEMS structure 120 is represented by a dashed line. It includes a mass block 121, a cantilever component 123, a suspension comb-like component 125, and multiple fixing parts 127. (Example...) Figure 1 As shown, one end of the cantilever component 123 is connected to the fixing part 127 on the left, and the other end of the cantilever component 123 is connected to the mass block 121. In addition, the fixing part 127 on the right includes a comb-shaped part 127-1 and a main part 127-2. The comb-shaped component 125 extends from the mass block 121 and is arranged to intersect the comb-shaped part 127-1 of the fixing part 127 in a finger-like manner. Figure 1The shapes and configurations of the mass block 121, cantilever component 123, suspended comb component 125, and fixing portion 127 shown are for illustrative purposes only, and embodiments of the present invention are not limited thereto. Furthermore, the number of cantilever components 123 connected to the mass block 121 can be adjusted according to actual needs, and the suspended comb component 125 can be replaced by a cantilever component 123 depending on different design requirements. During the operation of the MEMS device, when the MEMS structure 120 is subjected to external forces and moves or rotates, the cantilever component 123 may deform like a spring (e.g., compress or extend), causing a change in the distance between the fixing portion 127 and the mass block 121. Since the distance between the comb portion 127-1 and the suspended comb component 125 is inversely proportional to the capacitance value between the comb portion 127-1 and the suspended comb component 125, the acceleration and / or angular velocity of the MEMS structure 120 can be obtained by measuring the change in capacitance value between the comb portion 127-1 and the suspended comb component 125.

[0015] See Figure 2A In one embodiment, the MEMS device 100A includes a support substrate 101, which may be a silicon (Si) wafer or other suitable semiconductor wafer. The material of the support substrate 101 includes a single-crystal semiconductor material, such as silicon, sapphire, or other suitable semiconductor materials. For example, the material of the support substrate 101 may include an elemental semiconductor, such as Ge; the material of the support substrate 101 may also include a compound semiconductor, such as GaN, SiC, GaAs, GaP, InP, InAs, and / or InSb; the material of the support substrate 101 may also include an alloy semiconductor, such as SiGe, GaAsP, AlInAs, AlN, AlGaAs, GaInAs, GaInP, GaInAsP; or the material of the support substrate 101 may include a combination of the foregoing. A cavity 107 is formed on the top surface (or first surface) of the support substrate 101. Furthermore, a stop member 103 is formed in the cavity 107 on the top surface of the support substrate 101, and the stop member 103 is adjacent to the cavity 107. The stop component 103 is integrated with the support substrate 101, and the top surface of the stop component 103 is at the same height as the top surface of the support substrate 101. Figure 2A As shown in the MEMS device 100A, the depth D1 of the cavity 107 is substantially equal to the height H1 of the stop member 103 above the bottom surface of the cavity 107. In some embodiments, the stop member 103 and the support substrate 101 are integrally formed.

[0016] MEMS device 100A further includes a MEMS structure 120 disposed on a support substrate 101. The MEMS structure 120 may be formed from a silicon wafer, a polysilicon layer, or other suitable semiconductor layer. In some embodiments, the MEMS structure 120 includes a mass block 121, a cantilever member 123, a suspended comb member 125, a fixing portion 127 adjacent to the cantilever member 123, and another fixing portion 127 adjacent to the suspended comb member 125. The mass block 121 is disposed directly above the stop member 103, the cantilever member 123 and the suspended comb member 125 are disposed directly above the cavity 107, and the fixing portion 127 is disposed directly above the region of the support substrate 101 surrounding the cavity 107.

[0017] See Figure 2A The MEMS device 100A further includes a bonding dielectric layer 111 disposed between the top surface of the support substrate 101 and the bottom surface of the MEMS structure 120. The bonding dielectric layer 111 may be a silicon oxide layer. The fixing portion 127 of the MEMS structure 120 is bonded to the support substrate 101 through the bonding dielectric layer 111. The bonding dielectric layer 111 is disposed on the top surface of the support substrate 101 and does not extend to the sidewalls and bottom surface of the cavity 107. The bonding dielectric layer 111 also does not cover the stopping member 103, that is, the bonding dielectric layer 111 does not extend to the sidewalls and top surface of the stopping member 103. In addition, there is a gap 109 between the stopping member 103 and the mass block 121 of the MEMS device 100A. According to an embodiment of the present invention, in the height direction of the MEMS device 100A, for example, Figure 2A In the Z-axis direction shown, the size of the gap 109 is approximately the same as the thickness of the bonding dielectric layer 111. For example, the size of the gap 109 and the thickness of the bonding dielectric layer 111 can be approximately 1 micrometer (μm) to approximately 5 μm, but are not limited thereto. According to some embodiments of the present invention, the size of the gap 109 of the MEMS device can be precisely controlled by adjusting the thickness of the bonding dielectric layer 111. Typically, it is necessary to appropriately control the size of the gap 109 so that the mass 121 can be suspended above the stop member 103 during operation of the MEMS device 100A. Furthermore, when an external force is suddenly applied to the MEMS device 100A along the Z-axis, the stop member 103 can be used to prevent the mass 121 from moving in the Z-axis direction, thereby improving the performance of the MEMS device 100A.

[0018] In addition, the support substrate 101 also includes alignment marks 105 formed on the bottom surface of the support substrate 101. When the MEMS structure 120 is bonded to the support substrate 101, the alignment marks 105 can be used to help align the MEMS structure 120 with the support substrate 101.

[0019] like Figure 2AAs shown in the MEMS device 100A, in some embodiments, the MEMS structure 120 further includes a protrusion 128 disposed on the fixed portion 127, and a wire 129 disposed oriented along the protrusion 128. When the MEMS device 100A functions as an accelerometer or gyroscope, the mass block 121 can be used as a movable mass block. During operation of the MEMS device 100A, when an external force is applied to the MEMS device 100A, the movable mass block 121 may shift from its original position, the cantilever component 123 may vibrate at a resonant frequency, and the suspended comb component 125 may be displaced relative to the comb portion 127-1 of the fixed portion 127. The degree of displacement of the movable mass block 121, the cantilever component 123, and the suspended comb component 125 is converted into an electrical signal and then transmitted to an external circuit via the wire 129.

[0020] See also Figure 2B According to another embodiment of the present invention, a MEMS device 100B is provided. The difference between MEMS device 100B and MEMS device 100A is that MEMS device 100B includes multiple stopping components, for example, two stopping components 103 disposed directly below the mass block 121 of the MEMS structure 120. These two stopping components 103 are also disposed in and adjacent to the cavity 107 of the support substrate 101. Furthermore, in the height direction of MEMS device 100B, the top surfaces of these two stopping components 103 are at the same height as the top surface of the support substrate 101. Additionally, in the height direction of MEMS device 100B, the dimensions of the gap between the left stopping component 103 and the mass block 121, and another gap between the right stopping component 103 and the mass block 121, are approximately the same as the thickness of the bonding dielectric layer 111. In some embodiments, these two stopping components 103 and the support substrate 101 are integrally formed.

[0021] Figure 3A and Figure 3B This is a schematic cross-sectional view of a MEMS device according to some other embodiments of the present invention. (See also...) Figure 3AIn one embodiment, a MEMS device 100C is provided. The difference between MEMS device 100C and MEMS device 100A is that MEMS device 100C further includes a dielectric layer 113, which is disposed between the bottom surface of MEMS structure 120 and bonding dielectric layer 111. The dielectric layer 113 may be a silicon oxide layer. MEMS device 100C includes a gap 109 between stop member 103 and mass block 121. In this embodiment, the dimension of gap 109 in the height direction of MEMS device 100C is approximately the same as the total thickness of bonding dielectric layer 111 and dielectric layer 113, and the dimension of gap 109 of MEMS device 100C is precisely controlled by both the thickness of bonding dielectric layer 111 and the thickness of dielectric layer 113.

[0022] See also Figure 3B In another embodiment, a MEMS device 100D is provided, which differs from the MEMS device 100A in that the bonding dielectric layer 111 of the MEMS device 100D extends further to surround the sidewalls and bottom surface of the support substrate 101. Furthermore, the MEMS structure 120 of the MEMS device 100D may differ from the MEMS structure 120 of the MEMS device 100A. For example, the patterns of the mass block 121, cantilever member 123, suspended comb member 125, and fixing portion 127 of the MEMS structure 120 of the MEMS device 100D may differ from the patterns of the mass block 121, cantilever member 123, suspended comb member 125, and fixing portion 127 of the MEMS structure 120 of the MEMS device 100A. Furthermore, the cross-sectional shape of the protrusion 128 and the arrangement position of the wire 129 of the MEMS structure 120 of the MEMS device 100D may differ from the cross-sectional shape of the protrusion 128 and the arrangement position of the wire 129 of the MEMS structure 120 of the MEMS device 100A.

[0023] Figure 4 This is a schematic cross-sectional view illustrating the structure of a MEMS device bonded to a complementary metal-oxide-semiconductor (CMOS) wafer, according to an embodiment of the present invention. (See also...) Figure 4 Structure 200 includes a MEMS device 100 bonded to a CMOS wafer 130. The MEMS device 100 may be... Figure 2A , Figure 2B , Figure 3A and Figure 3BThe MEMS devices 100A, 100B, 100C, and 100D illustrated herein are any of the aforementioned MEMS devices, or variations thereof. The CMOS wafer 130 includes a semiconductor substrate 131 and an interconnect layer 132 formed on the semiconductor substrate 131. The semiconductor substrate 131 contains a plurality of CMOS transistors and other semiconductor elements formed therein. The interconnect layer 132 is composed of a plurality of metal layers, a plurality of dielectric layers, and a plurality of vias for electrically connecting to the CMOS transistors and semiconductor elements in the semiconductor substrate 131. The topmost metal layer of the interconnect layer 132 can serve as a bonding pad 133, and the wires 129 of the MEMS device 100 are bonded to the bonding pads 133 in the interconnect layer 132 of the CMOS wafer 130. Therefore, electrical signals of the MEMS device 100 can be transmitted to the CMOS wafer 130 through the wires 129 and the interconnect layer 132.

[0024] Figure 5 , Figure 6 and Figure 7 This is a cross-sectional schematic diagram illustrating some stages of a method for manufacturing a MEMS device according to an embodiment of the present invention. (See also...) Figure 5 First, a support substrate 101 is provided. The support substrate 101 may be a silicon wafer, but is not limited thereto. Next, in step S301, the support substrate 101 is etched to form a cavity 107 on the top surface of the support substrate 101, and a stop member 103 is formed in the cavity 107, the stop member 103 being adjacent to the cavity 107. In some embodiments, the stop member 103 and the cavity 107 are formed together in the same etching process step. Furthermore, the top surface of the stop member 103 is at the same height as the top surface of the support substrate 101, such as... Figure 5The dashed line TS is shown. With the bottom surface of cavity 107 as a reference, the depth of cavity 107 is approximately the same as the height of stop member 103. In this embodiment, stop member 103 and support substrate 101 are integrally formed. Furthermore, multiple alignment marks 105 can be formed on the bottom surface of support substrate 101 through an etching process. Then, in step S303, a bonding dielectric layer 111, such as a silicon oxide layer, is formed oriented sequentially on support substrate 101, inside cavity 107, and on stop member 103. The bonding dielectric layer 111 surrounds the top surface, sidewalls, and bottom surface of support substrate 101, and also extends to the sidewalls and bottom surface of cavity 107, and further to the sidewalls and top surface of stop member 103. The bonding dielectric layer 111 can be formed through processes such as thermal growth (e.g., thermal oxidation or thermal nitriding), plasma-enhanced chemical vapor deposition (PECVD) using tetraethoxysilane (TEOS), or atomic layer deposition, but is not limited thereto. In some embodiments, the thickness of the bonding dielectric layer 111 can be in the range of about 1 μm to about 5 μm, but is not limited thereto.

[0025] Next, refer to Figure 6 In step S305, a MEMS wafer 122 is provided, which is, for example, a silicon wafer, for forming MEMS structures in subsequent process steps. The MEMS wafer 122 has a thickness T1, for example, about 200 μm to about 1000 μm, but is not limited thereto. Then, in step S307, the MEMS wafer 122 is first bonded to the support substrate 101 and the stop member 103 through a bonding dielectric layer 111 using a fusion bonding process. Then, the MEMS wafer 122 is thinned by a back-side grinding process and a chemical mechanical polishing / planarization (CMP) process to form a MEMS device layer 124. The thickness T2 of the MEMS device layer 124 is less than the thickness T1 of the MEMS wafer 122, and the thickness T2 of the MEMS device layer 124 is, for example, about 10 μm to about 500 μm, but is not limited thereto.

[0026] Next, refer to Figure 7 In step S309, the MEMS device layer 124 is etched to form a plurality of protrusions 128, such as stand-off structures, on the top surface of the MEMS device layer 124. Then, conductive lines 129 are formed in the same direction on the protrusions 128. The conductive lines 129 can be formed by depositing a conductive material layer, such as a metal layer or a semiconductor layer, and then patterning the conductive material layer.

[0027] See also Figure 7 In step S311, the MEMS device layer 124 is patterned using lithography and etching processes to form a mass block 121, a cantilever component 123, a suspended comb component 125, and a fixing portion 127, thereby constituting a MEMS structure 120. According to an embodiment of the invention, during the patterning process of forming the mass block 121, cantilever component 123, suspended comb component 125, and fixing portion 127, an etchant, such as HF vapor but not limited thereto, is applied to the MEMS device layer 124, so that some portions of the MEMS device layer 124 exposed by the patterned mask (not shown) can be gradually etched away by the etchant. As the MEMS device layer 124 is continuously patterned, these portions of the MEMS device layer 124 are etched through, thereby forming linear cantilever components 123 and suspended comb components 125. At this time, the heavier mass block 121 is supported by and bonded to the stop component 103 to prevent the mass block 121 from moving. Therefore, streaks can be avoided when forming the sidewalls of the cantilever component 123 and the suspended comb component 125, and the patterns of the cantilever component 123 and the suspended comb component 125 are uniform. The cantilever component 123 and the suspended comb component 125 with uniform patterns help improve the reliability and production yield of MEMS devices, thereby reducing the differences in electrical characteristics and mechanical properties of multiple MEMS structures across the entire wafer.

[0028] Next, refer to Figure 7In step S313, a portion of the bonding dielectric layer 111 located between the mass block 121 and the stop member 103 is removed by an etching process to form a gap 109. Simultaneously, the mass block 121 of the MEMS structure 120 is released to become a movable mass block. In this embodiment, the dimension of the gap 109 in the height direction can be precisely controlled by the thickness of the bonding dielectric layer 111. Furthermore, as the weight of the mass block 121 increases, the thickness of the bonding dielectric layer 111 also increases. According to embodiments of the present invention, the manufacturing of the cantilever member 123 and the suspended comb member 125 is not limited by the mass block 121. Furthermore, even if the weight of the mass block 121 increases or decreases, the dimension of the gap 109 can have greater design flexibility, thereby increasing the flexibility of product adjustments for the MEMS device of the present invention. Additionally, portions of the bonding dielectric layer 111 on the sidewalls and bottom surface of the cavity 107, as well as on the sidewalls of the stop member 103, can also be removed by the same etching process steps used to form the gap 109, such as a vapor hydrofluoric acid (VHF) release process. In one embodiment, another portion of the bonding dielectric layer 111 on the sidewalls and bottom surface of the support substrate 101 can be removed by other etching processes, such as dry or wet etching processes. Finally, the remaining portion of the bonding dielectric layer 111 lies between the top surface of the support substrate 101 and the bottom surface of the MEMS structure 120 to form the MEMS device 100A.

[0029] Figure 8 , Figure 9 and Figure 10 This is a cross-sectional schematic diagram illustrating some stages of a method for manufacturing a MEMS device according to another embodiment of the present invention. Figure 5 After steps S301 and S303, refer to Figure 8 In step S305, a MEMS wafer 122 is provided, such as a silicon wafer, for forming MEMS structures in subsequent process steps. The MEMS wafer 122 has a thickness T1, for example, from about 200 μm to about 1000 μm, but is not limited thereto. Then, in step S306, a dielectric layer 113, such as a silicon oxide layer, is formed oriented on the MEMS wafer 122, the dielectric layer 113 surrounding the top surface, sidewalls, and bottom surface of the MEMS wafer 122. The dielectric layer 113 can be formed by a thermal growth process (e.g., a thermal oxidation process or a thermal nitriding process), a plasma-enhanced chemical vapor deposition (PECVD) process using tetraethoxysilane (TEOS), or an atomic layer deposition process, but is not limited thereto. In some embodiments, the thickness of the dielectric layer 113 can be in the range of from about 1 μm to about 5 μm, but is not limited thereto.

[0030] Next, refer to Figure 9 In step S307, fusion bonding is performed by bonding dielectric layers 111 and 113 to bond the MEMS wafer 122 to the support substrate 101 and the stop member 103, wherein dielectric layer 111 and dielectric layer 113 have dielectric-to-dielectric bonding. Then, the MEMS wafer 122 is thinned by a grinding process and a CMP process to form a MEMS device layer 124. The thickness T2 of the MEMS device layer 124 is less than the thickness T1 of the MEMS wafer 122, and the thickness T2 of the MEMS device layer 124 is, for example, about 10 μm to about 500 μm, but is not limited thereto. Furthermore, after the MEMS wafer 122 is thinned to form the MEMS device layer 124, the portions of the dielectric layer 113 on the top surface and sidewalls of the MEMS wafer 122 are also removed, so that the remaining portion of the dielectric layer 113 is between the bottom surface of the MEMS device layer 124 and the bonding dielectric layer 111.

[0031] See also Figure 9 In step S309, the MEMS device layer 124 is etched to form a plurality of protrusions 128, such as a support structure, on the top surface of the MEMS device layer 124. Then, conductive lines 129 are formed in the forward direction on the protrusions 128 by deposition and patterning processes.

[0032] Next, refer to Figure 10 In step S311, the MEMS device layer 124 is patterned by an etching process to form a mass block 121, a cantilever member 123, a suspended comb member 125, and a fixing portion 127, thereby constituting a MEMS structure 120. Furthermore, the dielectric layer 113 located on the bottom surface of the MEMS device layer 124 is also patterned by this etching process for forming the MEMS structure 120. According to an embodiment of the present invention, when the MEMS device layer 124 is continuously patterned to form fine lines of the cantilever member 123 and the suspended comb member 125, the heavier mass block 121 is supported by the stop member 103 and bonded to the stop member 103 to prevent the mass block from moving. Therefore, streaks are avoided from forming on the sidewalls of the cantilever member 123 and the suspended comb member 125, and the patterns of the cantilever member 123 and the suspended comb member 125 are uniform. The uniformly patterned cantilever component 123 and suspended comb component 125 contribute to improving the reliability and production yield of MEMS devices. Furthermore, according to embodiments of the invention, the manufacturing of the cantilever component 123 and suspended comb component 125 is not limited by the mass block 121, thereby increasing the flexibility of product adjustments for MEMS devices.

[0033] Next, refer to Figure 10In step S313, a portion of the bonding dielectric layer 111 and a portion of the dielectric layer 113 between the mass block 121 and the stop member 103 are removed by an etching process to form a gap 109, thereby releasing the mass block 121 of the MEMS structure 120. In this embodiment, the dimension of the gap 109 in the height direction is precisely controlled by the thickness of the bonding dielectric layer 111 and the dielectric layer 113. Furthermore, as the weight of the mass block 121 increases, the total thickness of the bonding dielectric layer 111 and the dielectric layer 113 also increases. Even if the weight of the mass block 121 increases or decreases, the dimension of the gap 109 can have greater design flexibility, thereby increasing the flexibility of the MEMS device of the present invention in product adjustment. Furthermore, the bonding dielectric layer 111 on the sidewalls and bottom surface of the cavity 107, and other portions on the sidewalls of the stop member 103, as well as other portions of the dielectric layer 113 in the region corresponding to the cavity 107, can also be removed by the same etching process steps used to form the gap 109, such as a vapor hydrofluoric acid (VHF) release process. In one embodiment, another portion of the bonding dielectric layer 111 on the sidewalls and bottom surface of the support substrate 101 can be removed by other etching processes, such as dry etching or wet etching. Finally, the remaining portions of the bonding dielectric layer 111 and the dielectric layer 113 are disposed between the top surface of the support substrate 101 and the bottom surface of the MEMS structure 120, thereby obtaining the MEMS device 100C.

[0034] exist Figure 2A , Figure 2B , Figure 3A and Figure 3B The MEMS structures 120 of MEMS devices 100A, 100B, 100C, and 100D illustrated are for illustrative purposes only, and embodiments of the present invention are not limited thereto. The MEMS devices of the present invention may include an inertial measurement unit (IMU), an inertial sensor, a pressure sensor, a microfluidic element, other micro-components, or a combination thereof, and the inertial measurement unit may include an accelerometer, a gyroscope, or a combination thereof.

[0035] According to embodiments of the present invention, during the manufacturing process, the mass block of the MEMS structure is supported and bonded to a stop component to prevent the mass block from moving downwards during the etching of the MEMS device layer. This ensures that other parts of the formed MEMS structure, such as the fine patterns of cantilever components and suspended comb-like components, are not limited by the weight of the mass block during the manufacturing process, thereby increasing the flexibility of product adjustment of the MEMS device. Additionally, the stop component can also serve as a mechanical stop component to resist impacts applied to the MEMS device.

[0036] Furthermore, according to embodiments of the present invention, streaks are avoided on the sidewalls of cantilever components and suspended comb-like components of the MEMS structure, and a uniform pattern is achieved, thereby improving the production yield and reliability of the MEMS device. Additionally, the gap size between the mass block and the stop component can be precisely controlled and more flexibly adjusted by the thickness of the bonding dielectric layer, or the total thickness of both the bonding dielectric layer and the dielectric layer. Therefore, in the MEMS device of embodiments of the present invention, the gap between the mass block and the stop component is adjustable. Furthermore, embodiments of the present invention can also form the stop component and the cavity together in the support substrate using the same etching process steps, without the need for additional photomasks and etching processes, thereby reducing the manufacturing time and cost of the MEMS device. The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made in accordance with the claims of the present invention should be included within the scope of the present invention.

Claims

1. A microelectromechanical device, characterized in that, include: One supporting substrate; A cavity is located on one top surface of the supporting substrate; A stopping component is adjacent to the cavity, and a top surface of the stopping component is at the same height as the top surface of the supporting substrate; A microelectromechanical structure (MEMS) is disposed on the support substrate. The MEMS includes a mass block and a cantilever component, wherein the mass block is disposed directly above the stop component and the cantilever component is disposed directly above the cavity. as well as A one-bonded dielectric layer is disposed between the top surface of the supporting substrate and a bottom surface of the microelectromechanical structure; The top surface of the mass block is coplanar with the top surface of the cantilever component, and the bottom surface of the mass block is coplanar with the bottom surface of the cantilever component. There is a gap between the stop component and the mass block, and the dimension of the gap in the height direction is the same as the thickness of the bonding dielectric layer.

2. The microelectromechanical device as described in claim 1, characterized in that, The bonding dielectric layer does not extend into the cavity, and the bonding dielectric layer comprises silicon oxide.

3. The microelectromechanical device of claim 1, wherein the bonding dielectric layer does not cover the stop component.

4. The microelectromechanical device as described in claim 1, characterized in that, It also includes a dielectric layer disposed between the bottom surface of the microelectromechanical structure and the bonding dielectric layer.

5. The microelectromechanical device as described in claim 1, characterized in that, The microelectromechanical system further includes a fixing part, one end of the cantilever component is connected to the fixing part, and the other end of the cantilever component is connected to the mass block.

6. The microelectromechanical device as described in claim 1, characterized in that, The microelectromechanical system further includes a suspended comb-like component and a fixing part, the suspended comb-like component extending from the mass block and configured to intersect the fixing part in a finger-like manner.

7. The microelectromechanical device as claimed in claim 1, characterized in that, The microelectromechanical system includes an inertial measurement unit, and the inertial measurement unit includes an accelerometer, a gyroscope, or a combination thereof.

8. The microelectromechanical device of claim 1, further comprising a complementary metal-oxide-semiconductor wafer bonded to the microelectromechanical structure, wherein the microelectromechanical structure further comprises a protrusion and a wire disposed on the protrusion, and the wire is bonded to a bonding pad of the complementary metal-oxide-semiconductor wafer.

9. The microelectromechanical device as claimed in claim 1, characterized in that, The stopping component and the supporting substrate are integrally formed.

10. A method for manufacturing a microelectromechanical device, characterized in that, include: Provide a support substrate; The support substrate is etched to form a cavity and a stop member on a top surface of the support substrate; A bonding dielectric layer is formed on the top surface of the supporting substrate and on one top surface of the stopping member; A microelectromechanical device (MEMS) layer is disposed on the bonding dielectric layer, and the MEMS layer is bonded to the stop component and the support substrate; The microelectromechanical device (MEMS) layer is patterned to form a microelectromechanical structure, wherein the microelectromechanical structure includes a mass block and a cantilever component, the mass block being bonded to the stop component and the cantilever component being formed directly above the cavity; as well as Remove a portion of the bonding dielectric layer located between the stop component and the mass block to form a gap between the stop component and the mass block.

11. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, The top surface of the stopping component is at the same height as the top surface of the supporting substrate, wherein a top surface of the mass block is coplanar with a top surface of the cantilever component, and a bottom surface of the mass block is coplanar with a bottom surface of the cantilever component.

12. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, After the cantilever component is formed, a portion of the bonding dielectric layer on the stop component is removed by an etching process.

13. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, The bonding dielectric layer is formed by a thermal oxidation process or a deposition process, and the bonding dielectric layer is formed in a conformal manner on the sidewalls and bottom surface of the cavity, as well as on the sidewalls and bottom surface of the supporting substrate.

14. The method for manufacturing a microelectromechanical device as described in claim 13, characterized in that, A first portion of the bonding dielectric layer on the sidewalls and bottom surface of the cavity is removed together with the portion of the bonding dielectric layer on the stop member by the same etching process.

15. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, The dimension of the gap in the height direction is the same as the thickness of the bonding dielectric layer.

16. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, Also includes: Provide a microelectromechanical wafer; Bond the microelectromechanical wafer to the supporting substrate; Thinning the microelectromechanical wafer to form the microelectromechanical device layer; Prior to forming the mass block, the microelectromechanical device layer is etched to form a protrusion of the microelectromechanical structure; A wire is formed on the protrusion of the microelectromechanical structure; A complementary metal-oxide-semiconductor wafer is provided, and an interconnect layer is included on the complementary metal-oxide-semiconductor wafer; as well as The microelectromechanical structure is bonded to the complementary metal-oxide-semiconductor wafer, wherein the wires are electrically coupled to the interconnect layer.

17. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, Patterning the microelectromechanical device layer to form the microelectromechanical structure further includes forming a fixing portion and a suspended comb-like component, wherein the suspended comb-like component extends from the mass block and is configured to intersect the fixing portion in a finger-like manner.

18. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, Patterning the microelectromechanical device layer to form the microelectromechanical structure also includes forming a fixing portion, wherein one end of the cantilever component is connected to the fixing portion and the other end of the cantilever component is connected to the mass block.

19. The method for manufacturing a microelectromechanical device as described in claim 10, characterized in that, Before the microelectromechanical device (MEMS) layer is disposed on the bonding dielectric layer, a dielectric layer is formed on the MEMS layer, wherein after the MEMS layer is disposed on the bonding dielectric layer, the dielectric layer is located between the MEMS layer and the bonding dielectric layer.

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