TWI846084B - Microelectromechanical systems package and method for manufacturing the same - Google Patents

Abstract

A microelectromechanical systems (MEMS) package includes a first MEMS package and a second MEMS package laterally spaced apart from the first MEMS package. The first MEMS package includes a first device substrate including a first MEMS device, a first cap substrate bonded to the first device substrate, where the first cap substrate encloses a first cavity and a vent hole connected to the first cavity. A first sealing layer is filled in the vent hole, where the first sealing layer is disposed between the first device substrate and the first cap substrate. The second MEMS package includes a second device substrate including a second MEMS device and a second cap substrate. The second cap substrate is bonded to the second device substrate and encloses a second cavity. The first cavity has a first pressure, and the second cavity have a second pressure different from the first pressure.

Description

Micro-electromechanical system package and manufacturing method thereof

The present disclosure relates to a micro-electromechanical system (MEMS) package and a method for manufacturing the same.

Microelectromechanical systems (MEMS) components, such as accelerometers, gyroscopes, pressure sensors, and microphones, have been widely used in many modern electronic components. For example, an inertial measurement unit (IMU) composed of an accelerometer and/or a MEMS gyroscope is commonly found in tablets, cars, or smartphones. In some applications, various MEMS components need to be integrated into one MEMS package. However, for MEMS components that require different pressures, these MEMS components need to be packaged separately under different ambient pressures and then integrated into one MEMS package. Therefore, the entire packaging process is complicated, and the MEMS package has a large footprint.

In view of this, the present disclosure provides a micro-electromechanical system (MEMS) package and a manufacturing method thereof to overcome the defects in the prior art.

In some embodiments of the present disclosure, a MEMS package includes a first MEMS package and a second MEMS package laterally separated from the first MEMS package. The first MEMS package includes a first component substrate including a first MEMS element, a first cover substrate bonded to the first component substrate, wherein the first cover substrate encloses a first cavity and a vent connected to the first cavity. A first sealing layer is filled in the vent, wherein the first sealing layer is disposed between the first component substrate and the first cover substrate. The second MEMS package includes a second component substrate, the second component substrate including a second MEMS element and a second cover substrate. The second cover substrate is bonded to the second component substrate and encloses a second cavity. The first cavity has a first pressure, and the second cavity has a second pressure different from the first pressure.

In some embodiments of the present disclosure, a method for manufacturing a MEMS package includes: providing a cover substrate including a first groove, a second groove, and a third groove, the first groove being connected to the third groove, the first groove and the third groove being laterally spaced from the second groove, wherein the depth of the first groove and the second groove is greater than the depth of the third groove; covering the first groove, the second groove, and the third groove with the cover substrate under ambient pressure to form a first cavity, a second cavity, and a third cavity; removing the cover substrate adjacent to an end of the third groove to form a vent; allowing a gas to flow through the vent under another ambient pressure different from the ambient pressure; and filling a sealing layer into the vent after the gas flows through the vent.

According to some embodiments of the present disclosure, the pressure of the first cavity can be controlled independently of the pressure of the second cavity. In addition, the pressure of the first cavity can be controlled by allowing gas to flow through the vent. Therefore, compared with the prior art, the entire packaging process is simplified and the MEMS package occupies a smaller area.

In order to make the features of this disclosure clear and easy to understand, the following is a detailed description of the embodiments with the help of the attached drawings.

100:MEMS packaging

102: Base substrate

102-1: Front side

102-2: Dorsal side

104: The first MEMS package

104a: First MEMS package

104b: First MEMS package

104c: First MEMS packaging

106: Second MEMS package

120: Cover substrate

120-2: Top surface

120a: first cover substrate

120b: Second cover substrate

122a: First cavity

122b: Second cavity

124: Ventilation hole

124a: Ventilation hole

124b: Ventilation hole

124c: Ventilation hole

126: External opening

128: Inner opening

130a: protruding part

130b: protruding part

132a: First lower cavity

132b: Second lower cavity

134a: First gap

134b: Second gap

140: Sealing layer

140a: First sealing layer

140b: Second sealing layer

142: End face

202: Supporting substrate

204:interconnection layer

206: Protective layer

210: Component substrate

210a: first component substrate

210b: Second component substrate

212: Bonding materials

214: First MEMS element

216: Second MEMS element

220: Bonding dielectric layer

220a: bonding dielectric layer

220b: Bonding dielectric layer

222: Conductive layer

222a: Conductive layer

222b: Conductive layer

402: Steps

404: Steps

406: Steps

408: Steps

410: Steps

412: Steps

414: Steps

422a: First groove

422b: Second groove

422c: The third groove

424: The third cavity

426: Round end

452: First Area

452a: First Area

452b: First Area

452c: First Area

452d: First Area

454: Second Area

D1: First Depth

D2: Second Depth

D3: The third depth

In order to make the following easier to understand, the drawings and their detailed text descriptions can be referred to simultaneously when reading this disclosure. Through the specific embodiments in this article and reference to the corresponding drawings, the specific embodiments of this disclosure are explained in detail and the working principles of the specific embodiments of this disclosure are explained. In addition, for the sake of clarity, the features in the drawings may not be drawn according to the actual scale, so the size of some features in some drawings may be deliberately enlarged or reduced.

FIG1 is a schematic top view of a micro-electromechanical system (MEMS) package according to some embodiments of the present disclosure.

FIG. 2 is a schematic cross-sectional view of a MEMS package along the section line A-A’ of FIG. 1 according to some embodiments of the present disclosure.

FIG. 3 is a schematic top view of different types of vents in a first MEMS package according to some embodiments of the present disclosure.

Figures 4 to 10 are cross-sectional schematic diagrams of different manufacturing stages of a manufacturing method for a MEMS package according to some embodiments of the present disclosure.

The present disclosure provides several different embodiments that can be used to implement different features of the present disclosure. For the purpose of simplifying the description, the present disclosure also describes examples of specific components and arrangements. The purpose of providing these embodiments is only for illustration and not for any limitation. For example, the description below for "a first feature is formed on or above a second feature" may refer to "the first feature and the second feature are in direct contact" or "there are other features between the first feature and the second feature", so that the first feature and the second feature are not in direct contact. In addition, various embodiments in the present disclosure may use repeated reference symbols and/or text annotations. These repeated reference symbols and annotations are used to make the description more concise and clear, rather than to indicate the relationship between different embodiments and/or configurations.

In addition, for the spatially related descriptive terms mentioned in this disclosure, such as "under", "low", "down", "above", "above", "up", "top", "bottom" and similar terms, for the convenience of description, their usage is to describe the relative relationship between one element or feature and another (or multiple) elements or features in the 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. With the different orientations of the semiconductor device (rotated 90 degrees or other orientations), the spatially related descriptions used to describe its orientation should also be interpreted in a similar manner.

Although the present disclosure uses the terms 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 a certain element, component, region, layer, and/or section from another element, component, region, layer, and/or section, and they do not imply or represent any previous sequence of the element, nor do they represent the arrangement order of a certain element and another element, or the order of the manufacturing method. Therefore, without departing from the scope of the specific embodiments of the present disclosure, the first element, component, region, layer, or section discussed below can also be referred to as the second element, component, region, layer, or section.

The terms "about" or "substantially" mentioned in this disclosure generally mean within 20% of a given value or range, preferably within 10%, and 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, in the absence of specific description of "about" or "substantially", the meaning of "about" or "substantially" can still be implied.

In addition, the terms "coupled to" and "electrically connected to" mentioned in this disclosure include any direct and indirect electrical connection methods. Therefore, if it is described in this article that a first component is coupled or electrically connected to a second component, it means that the first component can be directly connected to the second component, or can be indirectly connected to the second component through other components or other connecting devices.

Although the invention disclosed herein is described below by means of specific embodiments, the invention principles disclosed herein can also be applied to other embodiments. In addition, in order not to obscure the spirit of the invention, certain details will be omitted, and these omitted details belong to the knowledge scope of those with ordinary knowledge in the relevant technical field.

FIG. 1 is a schematic top view of a microelectromechanical system (MEMS) package according to some embodiments of the present disclosure. Referring to FIG. 1 , the MEMS package 100 includes a MEMS element, such as an accelerometer or a gyroscope, but is not limited thereto. In some embodiments, the MEMS package 100 includes a base substrate 102, and at least two sub-MEMS packages, such as a first MEMS package 104 and a second MEMS package 106, disposed on the same base substrate 102, and the first MEMS package 104 and the second MEMS package 106 are separated from each other laterally (e.g., in the x-direction).

The first MEMS package 104 includes a first MEMS element (not shown), a first cover substrate 120a, a first cavity 122a, a vent 124, and a first sealing layer 140a. The first MEMS element overlaps the first cavity 122a, and during operation of the first MEMS package 104, at least a portion of the first MEMS element, such as a proof mass or a suspension beam, can move, vibrate, and/or rotate in the space formed by the first cavity 122a. The first cavity 122a is enclosed by the first cover substrate 120a and the first sealing layer 140a. In some embodiments, the first cavity 122a has a predetermined pressure (e.g., a first pressure), the vent 124 is connected to the side wall of the first cavity 122a, the vent 124 includes a straight channel that passes through the first cover substrate 120a laterally, and at least a portion of the vent 124 is filled with the first sealing layer 140a.

In some embodiments, the first MEMS package 104 further includes a first element substrate (not shown) disposed below the first cover substrate 120a and the first cavity 122a in a vertical direction (e.g., in the Z direction). The first element substrate includes a protrusion 130a, which is a continuous structure extending downward from the main body of the first element substrate and bonded to the base substrate 102. A portion of the protrusion 130a overlaps the first cavity 122a, and the portion is spaced apart from the first vent 124 laterally (e.g., in the x direction).

1 , the second MEMS package 106 includes a second MEMS element (not shown), a second cover substrate 120b, a second cavity 122b, and a second sealing layer 140b. The second MEMS element overlaps with the second cavity 122a, and during operation of the second MEMS package 106, at least a portion of the second MEMS element, such as a detection mass or a cantilever beam, can move, vibrate, and/or rotate in the space formed by the second cavity 122b. The second cavity 122b is enclosed by the second cover substrate 120b and the second sealing layer 140b. In some embodiments, the second cavity 122b has a predetermined pressure (e.g., a second pressure), and the second MEMS package 106 further includes a second element substrate (not shown) disposed below the second cover substrate 120b and the second cavity 122b. The second element substrate includes a protrusion 130b, which is a continuous structure extending downward from the main body of the second element substrate and is bonded to the base substrate 102. The protrusion 130b surrounds the second cavity 122b, so that when viewed from a top view, the protrusion 130b does not overlap with the second cavity 122b.

FIG. 2 is a cross-sectional schematic diagram of a MEMS package taken along the section line A-A′ in FIG. 1 according to some embodiments of the present disclosure. Referring to FIG. 2 , a first MEMS package 104 and a second MEMS package 104 share the same base substrate 102. The base substrate 102 includes a supporting substrate 202 and an interconnect layer 204 disposed on the supporting substrate 202. In some embodiments, the supporting substrate 202 is a semiconductor substrate for accommodating semiconductor elements such as transistors, but is not limited thereto. In some embodiments, the supporting substrate 202 may be an insulating substrate without any active or passive elements. The interconnect layer 204 includes an inter metal dielectric (IMD) layer and a plurality of conductive interconnects and vias. The conductive interconnects and vias have a predetermined design layout and can be electrically coupled to the first MEMS element 212 and the second MEMS element 216 disposed on the interconnect layer 204. The protective layer 206 can be disposed on the interconnect layer 204 to protect a portion of the interconnect layer 204.

In some embodiments, the first element substrate 210a includes a first MEMS element 214 having an accelerometer or a gyroscope. The first element substrate 210a can be bonded to the base substrate 102 through a bonding material 212 disposed under the protrusion 130a. The bonding material 212 may include a eutectic bonding material including, but not limited to, Au-Ge, Au-Si, Al-Ge, Al-Si, or a combination thereof. The first lower cavity 132a can be defined by the protrusion 130a, which is disposed under the first MEMS element 214 and surrounded by the protrusion 130a.

In some embodiments, the first cover substrate 120a is disposed above the first element substrate 210a. In some embodiments, the first cover substrate 120a may be bonded to the first element substrate 210a by a bonding dielectric layer 220a disposed on a surface of the first cover substrate 120a. The bonding dielectric layer 220a may be a conformal layer disposed on the bottom surface of the first cover substrate 120a and disposed between the first element substrate 210a and the first cover substrate 120a. The bonding dielectric layer 220a and the first element substrate 210a enclose the first cavity 122a and the vent 124. The height of the first cavity 122a is greater than the height of the vent 124.

The conductive layer 222a is disposed on the top surface of the first cover substrate 120a, which may be a patterned conductive layer electrically coupled to the first MEMS element 214 and/or the conductive interconnects and vias in the interconnect layer 204.

The first sealing layer 140a is disposed on the side wall of the first cover substrate 120a, or further disposed on the side wall of the first element substrate 210a. A portion of the first sealing layer 140a may be filled in the vent hole 124, and the portion of the first sealing layer 140a may have an end surface 142 close to the first cavity 122a. In some embodiments, the end surface 142 of the first sealing layer 140a is disposed in the vent hole 124 and does not extend into the first cavity 122a. In other words, the end surface 142 of the first sealing layer 140a is spaced apart from the first cavity 122a laterally (e.g., in the x direction). In some embodiments, a portion of the first sealing layer 140a may be filled in the first gap 134a between the interconnect layer 204 and the first element substrate 210a.

The second element substrate 210b includes a second MEMS element 216 having an accelerometer or a gyroscope, and the type of the second MEMS element 216 is different from the type of the first MEMS element 214. For example, in the case where the first MEMS element 214 is a gyroscope enclosed in a cavity having a relatively low pressure, the second MEMS element 216 may be an accelerometer enclosed in a cavity having a relatively high pressure instead of a gyroscope. The second element substrate 210b may be bonded to the base substrate 102 by a bonding material 212 disposed under the protrusion 130b. The bonding material 212 may include a eutectic bonding material including, but not limited to, Au-Ge, Au-Si, Al-Ge, Al-Si, or a combination thereof. The second lower cavity 132b can be defined by the protrusion 130b, which is disposed below the second MEMS element 216 and surrounded by the protrusion 130b.

The second cover substrate 120b is disposed above the second element substrate 210b. In some embodiments, the second cover substrate 120b may be bonded to the second element substrate 210b by a bonding dielectric layer 220b disposed on a surface of the second cover substrate 120b. The bonding dielectric layer 220b may be a conformal layer disposed on the bottom surface of the second cover substrate 120b and disposed between the second element substrate 210b and the second cover substrate 120b. The bonding dielectric layer 220b and the second element substrate 210b enclose the second cavity 122b. The height of the second cavity 122b is greater than the height of the vent hole 124.

The conductive layer 222b is disposed on the top surface of the second cover substrate 120b, which may be a patterned conductive layer electrically coupled to the second MEMS element 216 and/or the conductive interconnects and vias in the interconnect layer 204.

The second sealing layer 140b is disposed on the sidewall of the second cover substrate 120b, or further disposed on the sidewall of the second element substrate 210b. In some embodiments, a portion of the second sealing layer 140b may be filled into the second gap 134b between the interconnect layer 204 and the second element substrate 210b. In some embodiments, the second sealing layer 140b has the same composition as the first sealing layer 140a, and both may be formed simultaneously by the same deposition and etching process.

According to some embodiments of the present disclosure, the first cavity 122a has a predetermined pressure, such as a first pressure (or first air pressure), which is different from the predetermined pressure of the second cavity 122b, such as a second pressure (or second air pressure). By allowing gas to flow into or out of the first cavity 122a through the vent 124, the pressure of the first cavity 122a can be controlled independently of the pressure of the second cavity 122b. In the case where the first MEMS element needs to operate at a relatively high pressure, such as a pressure greater than or equal to 1.0 standard atmospheric pressure (atm), and the second MEMS element needs to operate at a relatively low pressure, such as a pressure less than 1.0 atm, gas can flow from the surrounding environment through the vent 124 into the first cavity 122a. When the pressure of the first cavity 122a is substantially equal to the pressure of the surrounding environment, the vent hole 124 will be sealed by the first sealing layer 140a.

FIG. 3 is a top view schematic diagram of different types of vents in the first MEMS package according to some embodiments of the present disclosure. Referring to FIG. 3 , the vents in the first MEMS package 104 are not limited to the straight vents shown in FIG. 1 , and can be of different types, such as the vents 124a, 124b, 124c shown in FIG. 3 .

For the vent 124a of the first MEMS package 104a, the vent 124a includes an outer opening 126 away from the first cavity 122a and an inner opening 128 close to the first cavity 122a. In this case, the vent 124a is not a straight shape, but a non-linear shape (non-linear shape), including several channels extending in the X direction or the Y direction and connected to each other by the end. In the process of forming the first sealing layer 140a, the end surface 142 of the first sealing layer can be controlled so that the end surface 142 easily terminates in the vent 124a, because the vent 124a composed of channels perpendicular to each other can prevent the generated solid products from entering the first cavity 122a.

For the vent hole 124b of the first MEMS package 104b, the vent hole 124b is not a straight shape, but a nonlinear shape, such as a sawtooth shape. In the process of forming the first sealing layer 140a, the end surface 142 of the first sealing layer can be controlled so that the end surface 142 easily ends at the vent hole 124b, because the sawtooth-shaped vent hole 124b can prevent the generated solid products from entering the first cavity 122a.

For the vent hole 124c of the first MEMS package 104c, the vent hole 124c is not a straight shape, but a nonlinear shape, such as a wavy shape. In the process of forming the first sealing layer 140a, the end surface 142 of the first sealing layer can be controlled so that the end surface 142 easily ends at the vent hole 124c. This is because the wavy vent hole 124c can prevent the generated solid products from entering the first cavity 122a.

In order to enable those with general knowledge in the field to implement the present disclosure, the manufacturing method of the disclosed MEMS package is further described below.

Figures 4 to 10 are cross-sectional schematic diagrams of the manufacturing method of the MEMS package at different manufacturing stages according to some embodiments of the present disclosure.

4 , in step 402, a cover substrate 120 is provided. The cover substrate 120 may be a semiconductor substrate or an insulating substrate, but is not limited thereto. By performing photolithography and etching processes, a plurality of grooves (such as a first groove 422a, a second groove 422b, and a third groove 422c) may be formed on the top surface of the cover substrate 120. The first groove 422a and the third groove 422c are located in a first region 452 and connected to each other, and the second groove 422b is located in a second region 454 and is laterally (e.g., in the X direction) separated from the first groove 422a and the third groove 422c. In some embodiments, the first groove 422a, the second groove 422b, and the third groove 422c have a first depth D1, a second depth D2, and a third depth D3 in the Z direction. The first depth D1 and the second depth D2 are greater than the third depth D3. The size of the first groove 422a and the second groove 422b in the Y direction is greater than the size of the third groove 422c in the Y direction, for example, greater than twice. The bonding dielectric layer 220 is formed on the top surface of the cover substrate 120 and conformally covers the sidewalls and bottom surfaces of the first to third grooves 422a, 422b, 422c. In some embodiments, the bonding dielectric layer 220 may surround the entire cover substrate 120, which may be formed by a thermal oxidation process or a deposition process.

4 , in step 404, a bonding process such as a wafer bonding process may be performed to bond the device substrate 210 to the cover substrate 120 via the bonding dielectric layer 220, and the bonding dielectric layer 220 may be disposed between the device substrate 210 and the cover substrate 120. By performing the bonding process, the first recess 422a, the second recess 422b, and the third recess 422c may be covered by the device substrate 210 to become the first cavity 122a, the second cavity 122b, and the third cavity 424. By controlling the ambient pressure (e.g., chamber pressure) during the bonding process, the first cavity 122a, the second cavity 122b, and the third cavity 424 may have a predetermined pressure. For example, for a bonding process performed in a chamber having a chamber pressure of ^10-5 to 5 atm, the first cavity 122a, the second cavity 122b, and the third cavity 424 may also have a pressure equal to the chamber pressure in the bonding process.

Then, a patterning process may be performed to form protrusions, such as the first protrusion 130a and the second protrusion 130b shown in step 404, which extend from the main body of the device substrate 210. In some embodiments, the first protrusion 130a and the second protrusion 130b are formed by performing photolithography and etching processes, so that the first protrusion 130a and the second protrusion 130b can be formed integrally with the device substrate 210.

5 , in step 406 , a first MEMS element 214 and a second MEMS element 216 may be fabricated in the element substrate 210 . The first MEMS element 214 and the second MEMS element 216 may be part of an inertial measurement unit (IMU) and may be composed of a movable test mass, a movable cantilever beam, a movable cantilever ring, or a combination thereof, but is not limited thereto. In some embodiments, the type of the first MEMS element 214 is different from that of the second MEMS element 216 , for example, the first MEMS element 214 may be an accelerometer that needs to operate at a relatively high pressure, such as a pressure greater than or equal to 1.0 standard atmospheric pressure (atm), while the second MEMS element may be a gyroscope that needs to operate at a relatively low pressure, such as a pressure less than 1.0 atm. Then, a bonding material 212, such as a eutectic bonding material of Au-Ge, Au-Si, Al-Ge, Al-Si or a combination thereof, is formed on the protrusions 130a, 130b.

FIG. 6 is a schematic top view of different types of third cavities 424 in the first region 452 according to some embodiments of the present disclosure. Referring to FIG. 6 , in the first region 452a, the third cavity 424 is straight in shape and has a rounded end 426 away from the first cavity 122a and is covered by the cover substrate 120a. In addition to the straight third cavity 424, the third cavity 424 may have other shapes as shown in the corresponding first regions 452a, 452b, 452c, 452d.

For the third cavity 424 in the first region 452b, the third cavity 424 is not a straight shape, but a nonlinear shape, including a plurality of mutually connected and mutually perpendicular channels. For the third cavity 424 in the first region 452c, the third cavity 424 is not a straight shape, but a nonlinear shape, such as a wavy shape. For the third cavity 424 in the first region 452d, the third cavity 424 is not a straight shape, but a nonlinear shape such as a sawtooth shape.

7 , in step 408, a base substrate 102 is provided. In some embodiments, the base substrate 102 includes a support substrate 202 and an interconnect layer 204 disposed on the support substrate 202. In some embodiments, the support substrate 202 is a semiconductor substrate for accommodating semiconductor elements such as transistors, but is not limited thereto. In some embodiments, the support substrate 202 may be an insulating substrate without any transistors, and the interconnect layer 204 includes an intermetal dielectric (IMD) layer and a plurality of conductive interconnects and vias. The conductive interconnects and vias have a predetermined design layout and can be electrically coupled to the first MEMS element 214 and the second MEMS element 216 disposed on the interconnect layer 204. The protective layer 206 can be disposed on the interconnect layer 204 to protect a portion of the interconnect layer 204. The base substrate 102 has two opposing sides, such as a front side 102-1 and a back side 102-2. In a subsequent process, the front side 102-1 can face and bond to the element substrate.

Referring to FIG. 8 , in step 410, the base substrate 102 is bonded to the element substrate 210 by the bonding material 212. By performing the bonding process, the first lower cavity 132a is formed between the element substrate 210 and the base substrate 102 in the first region 452. Thus, during operation, at least a portion of the first MEMS element 214 can move, vibrate, or rotate in the space formed by the first lower cavity 132a and the first cavity 122a. In addition, by performing the bonding process, the second lower cavity 132b is formed between the element substrate 210 and the base substrate 102 in the second region 454. Thus, during operation, at least a portion of the second MEMS element 216 can move, vibrate, or rotate in the space formed by the second lower cavity 132b and the second cavity 122b.

After the bonding process, the cover substrate 120 may be thinned to a predetermined thickness. Then, a conductive layer 222, such as a metal layer, may be disposed on the top surface 120-2 of the cover substrate 120. The conductive layer 222 may be further patterned in a subsequent patterning process and electrically coupled to the first MEMS element 214, the second MEMS element 216, the interconnect layer 204, or a combination thereof. Optional conductive vias (not shown) may be formed in the cover substrate 120 and/or the element substrate 210, which are configured to transmit electrical signals to or from the first MEMS element 214 and the second MEMS element 216.

8 and 9 , in step 412, the cover substrate 120 at the interface between the first region 452 and the second region 454 is removed by etching, sawing or laser cutting. In some embodiments, the conductive layer 222, the bonding dielectric layer 220, and the device substrate 210b at the interface between the first region 452 and the second region 454 may also be removed simultaneously. During this removal process, the cover substrate 120 adjacent to the end of the third groove 424 may be removed. In addition, as shown in FIG. 6 , the round end 426 of the third groove 424 can be removed to obtain a vent hole 124 between the bonding dielectric layer 220a and the first element substrate 210a. The vent hole 124 includes an outer opening 126 connected to the surrounding environment and an inner opening 128 connected to the first cavity 122a. By allowing the gas in the surrounding environment to flow into or out of the first cavity 122a through the vent hole 124, the pressure of the first cavity 122a can be controlled. In this way, the pressure of the first cavity 122a can be equal to the environmental pressure.

10 , in step 414, a sealing layer 140 is formed to seal the vent hole 124. In some embodiments, the sealing layer 140 may be a blanket covering all components or members on the base substrate 102, and thus, the sealing layer 140 may cover the sidewalls of the first cover substrate 120a and the second cover substrate 120b, and the sidewalls of the first element substrate 210a and the second element substrate 210b. During the formation of the sealing layer 140, the pressure of the first cavity 122a is affected by the ambient pressure (e.g., chamber pressure) in the deposition chamber. In some embodiments, the pressure of the first cavity 122a may be substantially equal to the chamber pressure of the deposition chamber, however, once the vent hole 124 is sealed by the sealing layer 140, the pressure of the first cavity 122a will no longer be affected by the chamber pressure of the deposition chamber.

Subsequently, after step 414, other processes, such as etching processes, may be performed to obtain the MEMS package 100 shown in FIG. 2. By performing the etching process, the conductive layers 222a, 222b may be exposed, and the first sealing layer 140a and the second sealing layer 140b may be formed on the sidewalls of the first cover substrate 120a and the second cover substrate 120b, and on the sidewalls of the first element substrate 210a and the second element substrate 210b, respectively. In some embodiments, the first sealing layer 140a and the second sealing layer 140b are self-aligned structures obtained without performing a photolithography process.

The above is only the preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

100:MEMS packaging

102: Base substrate

104: The first MEMS package

106: Second MEMS package

120a: first cover substrate

120b: Second cover substrate

122a: First cavity

122b: Second cavity

124: Ventilation hole

130a: protruding part

130b: protruding part

132a: First lower cavity

132b: Second lower cavity

134a: First gap

134b: Second gap

140a: First sealing layer

140b: Second sealing layer

142: End face

202: Supporting substrate

204:interconnection layer

206: Protective layer

210a: first component substrate

210b: Second component substrate

212: Bonding materials

214: First MEMS element

216: Second MEMS element

220a: bonding dielectric layer

220b: Bonding dielectric layer

222a: Conductive layer

222b: Conductive layer

Claims (20)

A microelectromechanical system (MEMS) package includes: a first MEMS package, including: a first element substrate, including a first MEMS element; a first cover substrate bonded to the first element substrate, wherein the first cover substrate encloses a first cavity and a vent hole, wherein the vent hole is connected to the first cavity; and a first sealing layer filled in at least a portion of the vent hole, wherein the first sealing layer is disposed between the first element substrate and the first cover substrate; a second MEMS package, laterally separated from the first MEMS package, the second MEMS package includes: a second element substrate, including a second MEMS element; and a second cover substrate bonded to the second element substrate, wherein the second cover substrate encloses a second cavity, wherein the first cavity has a first pressure, and the second cavity has a second pressure different from the first pressure. A microelectromechanical system (MEMS) package as described in claim 1, wherein the first MEMS element includes an accelerometer, the second MEMS element includes a gyroscope, and the first pressure is greater than the second pressure. A microelectromechanical system (MEMS) package as described in claim 1, wherein the height of the first cavity is greater than the height of the vent hole. A microelectromechanical system (MEMS) package as described in claim 1, wherein the vent hole has a nonlinear shape or a linear shape when viewed from a top view. A microelectromechanical system (MEMS) package as described in claim 4, wherein the nonlinear shape includes a wavy shape or a sawtooth shape. A microelectromechanical system (MEMS) package as described in claim 1, wherein the first sealing layer includes an end surface located in the vent hole, and the end surface of the first sealing layer is separated from the first cavity. A microelectromechanical system (MEMS) package as described in claim 1, wherein the first sealing layer also covers the side walls of the first element substrate and the side walls of the first cover substrate. A microelectromechanical system (MEMS) package as described in claim 1, wherein the first MEMS package further includes a bonding dielectric layer disposed between the first element substrate and the first cover substrate, the bonding dielectric layer enclosing the first cavity and the vent. A microelectromechanical system (MEMS) package as described in claim 1, wherein the first component substrate further includes a protruding portion extending downward, a portion of the protruding portion overlaps with the first cavity and is laterally separated from the vent hole. A microelectromechanical system (MEMS) package as described in claim 9, wherein the first MEMS package further includes a first lower cavity surrounded by the protruding portion. A microelectromechanical system (MEMS) package as described in claim 1, wherein the first MEMS package further includes a conductive layer disposed on a top surface of the first cover substrate. A microelectromechanical system (MEMS) package as described in claim 11, wherein the conductive layer is electrically coupled to an interconnect layer disposed below the first component substrate. The microelectromechanical system (MEMS) package as described in claim 1 further includes an interconnect layer disposed below the first component substrate and the second component substrate, and the interconnect layer is bonded to the first component substrate and the second component substrate. A microelectromechanical system (MEMS) package as described in claim 13, wherein the interconnect layer is electrically coupled to the first MEMS element and the second MEMS element. A microelectromechanical system (MEMS) package as described in claim 13, wherein the first sealing layer is also filled in a gap between the interconnect layer and the first component substrate. A microelectromechanical system (MEMS) package as described in claim 1, wherein the second MEMS package further includes a second sealing layer covering the side wall of the second element substrate, and the second sealing layer has the same composition as the first sealing layer. A method for manufacturing a microelectromechanical system (MEMS) package, the microelectromechanical system package includes a first MEMS package and a second MEMS package, the method for manufacturing a microelectromechanical system package includes: providing a cover substrate, the cover substrate includes a first groove, a second groove and a third groove, the first groove is connected to the third groove, and the first groove and the third groove are laterally separated from the second groove, wherein the depth of the first groove and the second groove is greater than the depth of the third groove; Covering the first groove, the second groove and the third groove with a component substrate under an ambient pressure to form A first cavity in the first MEMS package, a second cavity in the second MEMS package, and a third cavity in the first MEMS package, wherein the positions of the first cavity, the second cavity, and the third cavity correspond to the positions of the first groove, the second groove, and the third groove, respectively; removing the cover substrate adjacent to an end of the third groove to form a vent connected to the first cavity; allowing gas to flow through the vent under another ambient pressure different from the ambient pressure; and filling a sealing layer into the vent after the gas flows through the vent. A method for manufacturing a microelectromechanical system (MEMS) package as described in claim 17, wherein, before forming the vent hole, the first cavity, the second cavity, and the third cavity have a pressure equal to the ambient pressure. A method for manufacturing a microelectromechanical system (MEMS) package as described in claim 17, wherein after the sealing layer is filled into the vent hole, the first cavity has a pressure equal to the other ambient pressure. A method for manufacturing a microelectromechanical system (MEMS) package as described in claim 19, wherein after the sealing layer is filled into the vent hole, the second cavity has another pressure equal to the ambient pressure.

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