Micro-electro-mechanical packaging and manufacturing method thereof

Abstract

A micro-electro-mechanical (MEMS) package includes a wafer on which an interconnect layer is disposed, a first element substrate including a first micro-electro-mechanical element, and a second element substrate including a second micro-electro-mechanical element, the first and second element substrates being laterally spaced apart from each other and disposed on the wafer. First and second bond seal rings are disposed under the first and second element substrates, respectively, and are both bonded to the interconnect layer. The first support substrate includes a first cavity having a first pressure, and is bonded to the first element substrate. The second support substrate includes a second cavity having a second pressure, the second pressure being different from the first pressure, and the second support substrate is bonded to the second element substrate.

Description

Technical Field

[0001] The present invention relates to a micro electro mechanical system (MEMS) package, and more particularly to a micro electro mechanical system package including a MEMS element with different pressures and a manufacturing method thereof. Background Art

[0002] Microelectromechanical (MEMS) components are miniature components that integrate mechanical and electrical components to sense physical quantities and / or interact with the surrounding environment. MEMS components such as accelerometers, gyroscopes, pressure sensors, and microphones have been widely used in many modern electronic products. For example, inertial measurement units (IMUs) composed of accelerometers and / or gyroscopes are commonly found in tablets, cars, or smartphones. For some applications, it is necessary to integrate various MEMS components into a MEMS package. However, for MEMS components that require different pressures, these MEMS components need to be packaged separately under different environmental pressures and then integrated into a MEMS package. Therefore, the packaging process of traditional MEMS packages is complicated, and traditional MEMS packages also require a larger footprint. Summary of the invention

[0003] In view of this, some embodiments of the present invention provide a microelectromechanical (MEMS) package and a method for manufacturing the same to overcome the aforementioned disadvantages of conventional MEMS packages. The MEMS package of the present invention includes a hole in a bonding seal ring to achieve pressure regulation of the cavity of the MEMS element after bonding. In addition, an anti-adhesion coating may be formed on the MEMS element during the pressure regulation process step. Therefore, compared to conventional MEMS packages, the packaging process of the MEMS package of the present invention including multiple MEMS elements with different cavity pressures can be simplified, and the MEMS package has a smaller footprint.

[0004] According to one embodiment of the present invention, a microelectromechanical (MEMS) package is provided, including a wafer, an interconnection layer, a first element substrate, a second element substrate, a first bonding sealing ring, a second bonding sealing ring, a first supporting substrate, a second supporting substrate, a hole and a dielectric film. The interconnection layer is arranged on the wafer, the first element substrate includes a first MEMS element and is arranged on the wafer, the second element substrate includes a second MEMS element and is arranged on the wafer, and the second element substrate is laterally separated from the first element substrate. The first bonding sealing ring is arranged below the first element substrate and bonded to the interconnection layer, and the second bonding sealing ring is arranged below the second element substrate and bonded to the interconnection layer. The first supporting substrate includes a first cavity and is bonded to the first element substrate, and the second supporting substrate includes a second cavity and is bonded to the second element substrate. The hole is arranged in the second bonding sealing ring, and the dielectric film is arranged on the interconnection layer and is adjacent to the first bonding sealing ring and the second bonding sealing ring. The first cavity has a first pressure, and the second cavity has a second pressure, and the second pressure is different from the first pressure.

[0005] According to one embodiment of the present invention, a method for manufacturing a micro-electromechanical package is provided, comprising the following steps: providing a support wafer, comprising forming a first cavity and a second cavity in the support wafer; providing an element wafer, comprising forming a first micro-electromechanical element and a second micro-electromechanical element laterally separated from each other in the element wafer; forming a first bonding sealing ring and a second bonding sealing ring, respectively below a first MEMS element and a second MEMS element; forming a hole in the second bonding sealing ring; forming two pre-cut lines in the element wafer, and located between the first MEMS element and the second MEMS element; bonding the support wafer to the element wafer, wherein the first cavity is located directly above the first MEMS element and the second cavity is located directly above the second MEMS element; providing a wafer and forming an interconnection layer on the wafer; bonding the element wafer to the interconnection layer on the wafer under a first pressure; removing a portion of the support wafer and a portion of the element wafer between the two pre-cut lines, exposing the hole in the second bonding sealing ring to ambient pressure; and forming a dielectric film on the interconnection layer.

[0006] In order to make the features of the present invention more clearly understood, embodiments are given below with reference to the accompanying drawings for detailed description as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In order to make the following text easier to understand, the drawings and their detailed text descriptions can be referred to when reading the present invention. The specific embodiments of the present invention are explained in detail through the specific embodiments in this article and with reference to the corresponding drawings, and the working principles of the specific embodiments of the present invention 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 sizes of some features in some drawings may be deliberately enlarged or reduced. Figure 1FIG. 4 is a schematic top view of a micro-electromechanical system (MEMS) package according to an embodiment of the present invention. Figure 2 FIG. 4 is a cross-sectional schematic diagram of a MEMS package according to an embodiment of the present invention. Figure 3 FIG. 4 is a schematic top view of a MEMS package according to another embodiment of the present invention. Figure 4 FIG. 4 is a cross-sectional schematic diagram of a MEMS package according to another embodiment of the present invention. Figure 5 , Figure 6 and Figure 7 Schematic cross-sectional views of some intermediate stages of a method for manufacturing a MEMS package according to an embodiment of the present invention. Figure 8 , Fig. 9 and Fig.10 FIG. 4 is a cross-sectional schematic diagram of some intermediate stages of a method for manufacturing a MEMS package according to another embodiment of the present invention. The following are the descriptions of the reference numerals: 100…MEMS packaging 100A…First MEMS area 100B…Second MEMS area SL…cutting road 110…Support wafer 110A…first supporting substrate 110B...second supporting substrate 110F, 110K, 110T…Surface 112…First cavity 114…Second cavity 116…Bonding layer 116A…First bonding layer 116B…Second bonding layer 118, 118A, 118B ... conductive layer 120…Component wafer 120A…First component substrate 120B…Second component substrate 120P…part of the component wafer 121…Support protrusion 122…First MEMS element 123, 127…groove 124…Second MEMS element 125A…First bond seal ring 125B…Second bonding seal ring 126…Bonding materials 130…Wafer 132…Interconnect layer 134…Protective layer 140…Vents / holes 142…holes 145…Anti-adhesion coating 150…Step structure 151, 152, 153…Pre-cut wire 152P…Protruding part 154…Joint pad 160…Dielectric film 161…Dielectric material layer 170…Sealing layer S101, S103, S105, S107, S201, S202, S203, S205, S207...steps DETAILED DESCRIPTION

[0008] The present invention provides several different embodiments that can be used to implement different features of the present invention. For the sake of simplicity of description, the present invention also describes examples of specific components and arrangements. The purpose of providing these embodiments is only for illustration, 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 is in direct contact with the second feature" or "there are other features between the first feature and the second feature", so that the first feature is not in direct contact with the second feature. In addition, various embodiments of the present invention may use repeated figure marks and / or text annotations. The use of these repeated figure marks and annotations is to make the description more concise and clear, rather than to indicate the association between different embodiments and / or configurations.

[0009] In addition, for the spatially related descriptive words mentioned in the present invention, such as "below", "lower", "below", "above", "on", "top", "bottom" and similar words, 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 accompanying drawings. In addition to the swing directions shown in the accompanying drawings, these spatially related words are also used to describe the possible swing directions of the MEMS package during use and operation. As the MEMS package swings in different directions (rotated 90 degrees or other orientations), the spatially related descriptions used to describe its swing direction should also be interpreted in a similar manner.

[0010] Although the present invention uses the terms first, second, third, etc. to describe various elements, components, regions, layers, and / or blocks, it should be understood that these elements, components, regions, layers, and / or blocks should not be limited by such terms. Such terms are only used to distinguish a certain element, component, region, layer, and / or block from another element, component, region, layer, and / or block, and do not imply or represent any previous ordinal number of the elements, nor do they represent the order of arrangement of a certain element and another element, or the order of manufacturing method. Therefore, without departing from the scope of the specific embodiments of the present invention, the first element, component, region, layer, or block discussed below can also be referred to as the second element, component, region, layer, or block.

[0011] The terms "about" or "substantially" mentioned in the present invention 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 a specific description of "about" or "substantially", the meaning of "about" or "substantially" can still be implied.

[0012] The terms "coupling", "coupling" and "electrical connection" mentioned in the present invention include any direct and indirect electrical connection means. For example, if the text describes that a first component is coupled to a second component, it means that the first component can be directly electrically connected to the second component, or indirectly electrically connected to the second component through other devices or connection means.

[0013] Although the present invention is described below by specific embodiments, the inventive principle of the present invention can also be applied to other embodiments. In addition, in order not to obscure the spirit of the present invention, specific details will be omitted, and these omitted details belong to the knowledge scope of those with ordinary knowledge in the relevant technical field.

[0014] The present invention relates to a micro-electromechanical (MEMS) package and a method for manufacturing the same, wherein the MEMS package includes a first MEMS element packaged under a first pressure, and a second MEMS element packaged under a second pressure, the second pressure being different from the first pressure. In some embodiments, the MEMS package may include an inertial measurement unit (IMU), which may include an accelerometer and a gyroscope, and other MEMS elements that require different pressures. In some embodiments, the first MEMS element may be a gyroscope that requires a first pressure of high vacuum, and the second MEMS element may be an accelerometer that requires a second pressure of low vacuum. A first bonding seal ring and a second bonding seal ring are respectively arranged corresponding to the first MEMS element and the second MEMS element, and a hole is arranged in the second bonding seal ring to form a vent hole, thereby achieving post-bonding pressure regulation of the second cavity of the second MEMS element. In addition, during the process step of post-bonding pressure regulation, an anti-stiction coating layer may also be formed on the second MEMS element through the vent hole. Therefore, the packaging process of the micro-electromechanical package including various MEMS elements with different cavity pressures is simplified, and the footprint of the micro-electromechanical package is smaller than that of a conventional micro-electromechanical package.

[0015] Figure 11 is a schematic top view of a micro-electromechanical package 100 according to an embodiment of the present invention. The micro-electromechanical package 100 includes various MEMS elements separated from each other. For example, a first MEMS element 122 is located in a first MEMS area 100A, and a second MEMS element 124 is located in a second MEMS area 100B. The first MEMS area 100A and the second MEMS area 100B are separated by a cutting line SL. Two pre-cutting lines 151 and 152 are formed in the cutting line SL and are located between the first MEMS element 122 and the second MEMS element 124. In addition, a plurality of bonding pads 154 are provided in the cutting line SL and are located between the two pre-cutting lines 151 and 152. Another pre-cutting line 153 is also formed in the cutting line SL. The operation of the first MEMS element 122 and the second MEMS element 124 requires different vacuum degrees, and the MEMS structures of the first MEMS element 122 and the second MEMS element 124 are different. The first MEMS element 122 and the second MEMS element 124 may include various component features, such as standoff bumps 121, grooves 127, proof mass (not shown), and the layout of the standoff bumps 121, grooves 127, and other component features of the first MEMS element 122 is different from the layout of those component features of the second MEMS element 124. In some embodiments, the first MEMS element 122 is, for example, a gyroscope requiring high vacuum, and the second MEMS element 124 is, for example, an accelerometer requiring low vacuum or atmospheric pressure. In addition, the second MEMS element 124 may require an anti-stiction coating, while the first MEMS element 122 may not require an anti-stiction coating, but is not limited thereto.

[0016] In addition, the micro-electromechanical package 100 includes a first cavity 112 located directly above the first MEMS element 122, and a second cavity 114 located directly above the second MEMS element 124. The first cavity 112 has a first pressure, and the second cavity 114 has a second pressure. Since the first MEMS element 122 and the second MEMS element 124 require different cavity pressures, the second pressure is different from the first pressure. From a top view, the first MEMS element 122 and the second MEMS element 124 may each include a groove 123 located outside or inside the range of their cavities. In addition, the micro-electromechanical package 100 includes a first bonding sealing ring 125A disposed corresponding to the first MEMS element 122, and a second bonding sealing ring 125B disposed corresponding to the second MEMS element 124. In some embodiments, a hole 140 is disposed in the second bonding sealing ring 125B to form a vent hole for adjusting the pressure in the second cavity 114. The hole 140 is formed laterally through the second bonding sealing ring 125B (for example, along the Y-axis direction) and is connected to the second cavity 114. In other embodiments, a plurality of holes 140 may be provided in the second bonding sealing ring 125B to form a plurality of vents for adjusting the pressure in the second cavity 114, each hole 140 is formed laterally through the second bonding sealing ring 125B (for example, along the X-axis or Y-axis direction), and all holes 140 are connected to the second cavity 114. In some embodiments, the width of each hole 140 in the X-axis or Y-axis direction may be between about 1 micrometer (μm) and about 100 μm, and the length of each hole 140 in the Y-axis or X-axis direction is substantially the same as the width of the second bonding sealing ring 125B.

[0017] Figure 2 is a cross-sectional schematic diagram of a micro-electromechanical package 100 according to an embodiment of the present invention, which is along Figure 1 In order to make the attached figure concise and easy to understand, Figure 2 The cross-sectional details of the first MEMS element 122 and the second MEMS element 124 are simplified, wherein the number of grooves 127 and the component dimensions between the grooves 127 do not completely correspond to Figure 1, those simplified detailed structures belong to those with ordinary knowledge in the relevant technical field that can be understood. The micro-electromechanical package 100 includes a wafer 130 and an interconnection layer 132 formed on the wafer 130. The wafer 130 may include a plurality of complementary metal oxide semiconductors (CMOS) or other components formed therein, and the interconnection layer 132 includes a plurality of metal layers, a plurality of inter-metal dielectric (IMD) layers, and a plurality of vias (vias) located in the IMD layer for connecting two metal layers. A bonding pad 154 is disposed on the top metal layer of the interconnection layer 132, and a protective layer 134 is also disposed on the top metal layer of the interconnection layer 132 and has a plurality of openings to expose the bonding pads 154 respectively. In addition, the micro-electromechanical package 100 includes a first element substrate 120A and a second element substrate 120B. The first element substrate 120A includes a first MEMS element 122 and is disposed on a wafer 130. The second element substrate 120B includes a second MEMS element 124 and is also disposed on the wafer 130. The second element substrate 120B is laterally spaced from the first element substrate 120A. In order to make the drawings simple and easy to understand, Figure 2 The MEMS structure of the first MEMS element 122 and the second MEMS element 124 is simplified in FIG. In addition, the first bonding sealing ring 125A is disposed below the first element substrate 120A and is bonded to the interconnect layer 132 via the bonding material 126. The second bonding sealing ring 125B is disposed below the second element substrate 120B and is also bonded to the interconnect layer 132 via the bonding material 126. In some embodiments, the first bonding sealing ring 125A and the first element substrate 120A can be an integrally formed structure and have the same composition, such as silicon. The second bonding sealing ring 125B and the second element substrate 120B can also be an integrally formed structure and have the same composition, such as silicon. The bonding material 126 is used to produce eutectic bonding with the top metal layer of the interconnect layer 132, such as germanium (Ge).

[0018] In addition, the micro-electromechanical package 100 includes a first support substrate 110A, which is bonded to a first element substrate 120A via a first bonding layer 116A, and a second support substrate 110B, which is bonded to a second element substrate 120B via a second bonding layer 116B. The first support substrate 110A includes a first cavity 112 formed therein, and the first cavity 112 is arranged directly above the first MEMS element 122. The second support substrate 110B includes a second cavity 114 formed therein, and the second cavity 114 is arranged directly above the second MEMS element 124. The first bonding layer 116A is arranged between the first element substrate 120A and the first support substrate 110A. In some embodiments, the first bonding layer 116A can further extend into the first cavity 112 to be conformally arranged on the sidewalls and bottom surface of the first cavity 112. The second bonding layer 116B is disposed between the second element substrate 120B and the second support substrate 110B, and the second bonding layer 116B may also extend into the second cavity 114 to be disposed in a forward direction on the sidewall and bottom surface of the second cavity 114. In addition, a conductive layer 118A may be disposed on the top surface of the first support substrate 110A, and a conductive layer 118B may be disposed on the top surface of the second support substrate 110B. The conductive layer 118A may be a patterned conductive layer electrically coupled to the first MEMS element 122 and / or the interconnection layer 132, and the conductive layer 118B may be a patterned conductive layer electrically coupled to the second MEMS element 124 and / or the interconnection layer 132.

[0019] In some embodiments, Figure 2 As shown, the hole 140 passes through the second bonding seal ring 125B laterally along the X-axis direction, and is connected to the second cavity 114 via the groove of the second MEMS element 124. Therefore, after the second element substrate 120B is bonded to the interconnect layer 132 on the wafer 130, the hole 140 can be used as a vent hole to adjust the pressure in the second cavity 114 to reach the pressure required by the second MEMS element 124. In some embodiments, in the Z-axis direction, the height of the vent hole / hole 140 can be the same as or slightly smaller than the thickness of the second bonding seal ring 125B, and the height of the vent hole / hole 140 can be, for example, about 1 μm to about 2 μm.

[0020] In some embodiments, the first cavity 112 has a first pressure P1, and the second cavity 114 can adjust the pressure in the second cavity 114 through the vent hole / hole 140 in the second bonding seal ring 125B, so that the second cavity 114 has a second pressure P2 different from the first pressure P1. During the process step of bonding the first component substrate 120A to the interconnect layer 132 on the wafer 130, the first pressure P1 in the first cavity 112 can be controlled and determined. After the second component substrate 120B is bonded to the interconnect layer 132 on the wafer 130, the pressure in the second cavity 114 can be adjusted to a desired vacuum degree through the vent hole / hole 140 to obtain the second pressure P2 in the second cavity 114. In addition, during the process step of adjusting the pressure in the second cavity 114, the anti-adhesion coating 145 can be formed on the second component substrate 120B through the vent hole / hole 140 to wrap the second MEMS element 124. After the second pressure P2 in the second cavity 114 is adjusted to a desired vacuum degree and the anti-adhesion coating 145 is formed on the second MEMS element 124, a dielectric film 160 may be formed on the interconnect layer 132, wherein a portion of the vent hole / hole 140 is filled with the dielectric film 160 to reseal the vent hole / hole 140. In this embodiment, the top surface of the interconnect layer 132 may provide a step structure for depositing the dielectric film 160 to reseal the vent hole / hole 140. The dielectric film 160 may be formed on the protective layer 134 and adjacent to the first bonding seal ring 125A and the second bonding seal ring 125B. Since the height of the vent hole / hole 140 is very small, for example, about 1 μm to about 2 μm, the vent hole / hole 140 may be easily resealed by depositing the dielectric film 160 on the interconnect layer 132. In addition, in this embodiment, a portion of the bonding material 126 may be formed on the back surface of the second element substrate 120B in the region of the hole 140 , and the dielectric film 160 is adjacent to the portion of the bonding material 126 .

[0021] Figure 3 FIG. 1 is a top view of a MEMS package 100 according to another embodiment of the present invention. Figure 3In the micro-electromechanical package 100, the hole 142 is arranged in the second bonding sealing ring 125B and vertically passes through the second bonding sealing ring 125B along the Z-axis direction. From the top view, the hole 142 is surrounded by the second bonding sealing ring 125B, and the hole 142 does not pass through the second bonding sealing ring 125B laterally in the Y-axis or X-axis direction. In addition, in this embodiment, the pre-cut line 152 adjacent to the second bonding sealing ring 125B has a protruding portion (platform structure) 152P corresponding to the position of the hole 142, and the protruding portion 152P protrudes outward away from the hole 142, and a step structure can be provided on the outside of the vent formed by the hole 142 through the protruding portion 152P. In some embodiments, a plurality of holes 142 can be formed in the second bonding sealing ring 125B, and the pre-cut line 152 has a plurality of protruding portions 152P corresponding to these holes 142. Figure 3 The details of other components and features of the MEMS package 100 can be found in the aforementioned Figure 1 The relevant description of the MEMS package 100 will not be repeated here.

[0022] Figure 4 is a cross-sectional schematic diagram of a MEMS package 100 according to another embodiment of the present invention, which is along Figure 3 In order to make the attached figure concise and easy to understand, Figure 4 The cross-sectional details of the first MEMS element 122 and the second MEMS element 124 are simplified, wherein the number of grooves 127 and the component dimensions between the grooves 127 do not completely correspond to Figure 3 , those simplified detailed structures are understandable to those with ordinary knowledge in the relevant technical field. The micro-electromechanical package 100 includes a hole 142 disposed in the second bonding sealing ring 125B, the hole 142 vertically passes through the second bonding sealing ring 125B in the Z-axis direction, and further extends to pass through the second element substrate 120B. In this embodiment, a portion of the second bonding layer 116B located between the second element substrate 120B and the second support substrate 110B can be removed by an etching process through the hole 142 to form a vent hole 140 in the second bonding layer 116B. Figure 4 As shown, in some embodiments, the vent hole 140 extends laterally along the X-axis direction between the second element substrate 120B and the second support substrate 110B. In addition, the vent hole 140 is connected to the second cavity 114 and the hole 142, and the second pressure P2 in the second cavity 114 can be adjusted to a desired vacuum degree through the vent hole 140, so that the second pressure P2 in the second cavity 114 is different from the first pressure P1 in the first cavity 112.

[0023] In addition, in this embodiment, if Figure 3As shown in FIG. 1 , the pre-cut line 152 adjacent to the second bonding seal ring 125B has a protruding portion 152P. After the cutting process is performed on the cutting street SL, as shown in FIG. Figure 4 As shown, the second element substrate 120B and the second support substrate 110B constitute a step structure 150 adjacent to the hole 142, and the vent hole 140 formed through the hole 142 is located in the step structure 150. In addition, during the process step of adjusting the pressure in the second cavity 114, the anti-adhesion coating 145 can be disposed on the second element substrate 120B in a conformal manner through the vent hole 140 to wrap the second MEMS element 124. When the second pressure P2 in the second cavity 114 is adjusted to a desired vacuum degree and the anti-adhesion coating 145 is formed on the second MEMS element 124 through the vent hole 140, a sealing layer 170 is deposited on the platform of the step structure 150 so that a portion of the vent hole 140 is filled with the sealing layer 170 to reseal the vent hole 140. In addition, a dielectric film 160 may be formed on the protection layer 134 of the interconnect layer 132 and located adjacent to the first bonding seal ring 125A and the second bonding seal ring 125B. In some embodiments, the sealing layer 170 and the dielectric film 160 may be formed by the same deposition process and have the same composition, such as silicon oxide.

[0024] In some embodiments, Figure 4 As shown, the first bonding layer 116A is disposed between the first element substrate 120A and the first support substrate 110A, and does not extend to the sidewalls and the bottom surface of the first cavity 112. The second bonding layer 116B is disposed between the second element substrate 120B and the second support substrate 110B, and does not extend to the sidewalls and the bottom surface of the second cavity 114. The portion of the second bonding layer 116B corresponding to the hole 142 may be removed to form the vent 140. In some embodiments, in the Z-axis direction, the height of the vent 140 may be the same as or slightly less than the thickness of the second bonding layer 116B. For example, the height of the vent 140 may be about 1000 Å. to about In some embodiments, the width of the vent hole 140 in the Y-axis direction may be in a range of about 1 μm to about 100 μm, and the length of the vent hole 140 in the X-axis direction may be the same as the width of the second bonding layer 116B. Figure 4 The details of other components and features of the MEMS package 100 can be found in the aforementioned Figure 2 The relevant description of the MEMS package 100 will not be repeated here.

[0025] Figure 5 , Figure 6 and Figure 72 is a cross-sectional schematic diagram of some intermediate stages of a method for manufacturing a micro-electromechanical system package according to an embodiment of the present invention. Figure 5 In step S101, a handle wafer 110, such as a silicon wafer, is first provided, and an etching process is performed on the surface 110F of the handle wafer 110 to form a first cavity 112 and a second cavity 114. Then, a bonding layer 116 is deposited on the handle wafer 110 and in the first cavity 112 and the second cavity 114 in a forward direction to wrap the handle wafer 110. The bonding layer 116 is composed of, for example, silicon dioxide, and the bonding layer 116 can be formed by thermal oxidation or a deposition process. In addition, a device wafer 120, such as a silicon wafer, is provided, and the device wafer 120 is bonded to the surface 110F of the handle wafer 110 to cover the first cavity 112 and the second cavity 114. Thereafter, the device wafer 120 is patterned by photolithography and etching processes to form a first MEMS element 122 and a second MEMS element 124 that are laterally separated from each other. As shown in FIG. Figure 5 As shown, the device wafer 120 includes a first device substrate 120A having a first MEMS device 122, a second device substrate 120B having a second MEMS device 124, and a portion 120P of the device wafer 120 located between the first device substrate 120A and the second device substrate 120B. A pre-cut line 151 is formed in the device wafer 120 and is located between the first device substrate 120A and the portion 120P of the device wafer 120, another pre-cut line 152 is formed in the device wafer 120 and is located between the second device substrate 120B and the portion 120P of the device wafer 120, and these two pre-cut lines 151 and 152 are formed between the first MEMS device 122 and the second MEMS device 124. The pre-cut lines 151 and 152, as well as the grooves of both the first MEMS device 122 and the second MEMS device 124 can be formed simultaneously by the same etching process, such as a deep reactive ion etching (DRIE) process.

[0026] In addition, a first bonding sealing ring 125A and a second bonding sealing ring 125B are formed, corresponding to the first MEMS element 122 and the second MEMS element 124, respectively, wherein the first bonding sealing ring 125A and the first element substrate 120A may be an integrally formed structure formed by the element wafer 120, and the second bonding sealing ring 125B and the second element substrate 120B may also be an integrally formed structure formed by the element wafer 120. The first bonding sealing ring 125A and the second bonding sealing ring 125B may be formed by patterning the element wafer 120. In this embodiment, the second bonding sealing ring 125B may be formed by an etching process as shown in FIG. Figure 1The hole 140 is shown, and the hole 140 laterally passes through the second bonding sealing ring 125B. Afterwards, a bonding material 126, such as germanium (Ge), is formed on the first bonding sealing ring 125A and the second bonding sealing ring 125B, wherein the bonding material 126 is formed on the second element substrate 120B in the region of the hole 140.

[0027] Still reading Figure 5 , in step S103, the bonded support wafer 110 and the element wafer 120 are turned upside down, wherein the first cavity 112 is located directly above the first MEMS element 122, and the second cavity 114 is located directly above the second MEMS element 124. Afterwards, a wafer 130 is provided, for example, a CMOS wafer having an interconnection layer 132 formed thereon. Then, under a first pressure P1, the element wafer 120 is bonded to the interconnection layer 132 on the wafer 130 through a bonding material 126. In step S103, both the first cavity 112 and the second cavity 114 have the first pressure P1. In addition, a grinding or etching process is performed on the other surface 110K of the support wafer 110 to thin the support wafer 110. Then, a conductive layer 118, for example, an aluminum (Al) layer, is deposited on the top surface 110T of the thinned support wafer 110.

[0028] Next, see Figure 6In step S105, a portion of the support wafer 110 and a portion 120P of the element wafer 120 located between the two pre-cut lines 151 and 152 on the scribe line SL are removed by a cutting process, so that the hole 140 is exposed to the ambient pressure, and the bonding pad 154 on the scribe line SL can also be exposed by the cutting process. In step S105, the first cavity 112 directly above the first MEMS element 122 still maintains the first pressure P1 of step S103. In addition, the hole 140 in the second bonding seal ring 125B is exposed and used as a vent to adjust the pressure in the second cavity 114, so that the pressure in the second cavity 114 can be adjusted to a second pressure P2 different from the first pressure P1. In addition, in some embodiments, during the process step of adjusting the pressure in the second cavity 114, the anti-adhesion coating 145 can be deposited on the second element substrate 120B in a forward direction through the vent / hole 140 to wrap the second MEMS element 124. In some embodiments, the anti-adhesion coating 145 may be a self-assembled monolayer (SAM) coating formed by a vapor deposition process. The composition of the anti-adhesion coating 145 may be an organic material, such as 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS), octadecyltrichlorosilane (OTS) or dichlorodimethylsilane (DDMS), but is not limited thereto.

[0029] Afterwards, see Figure 7 In step S107, a dielectric material layer 161 is deposited on the interconnect layer 132 by a blanket deposition process, such as a chemical vapor deposition (CVD), a physical vapor deposition (PVD), or an atomic layer deposition (ALD) process, to reseal the vent / hole 140 at the second pressure P2. In addition, the dielectric material layer 161 is also deposited on the conductive layers 118A and 118B, and the composition of the dielectric material layer 161 is, for example, silicon oxide. Thereafter, those portions of the dielectric material layer 161 located on the conductive layers 118A and 118B are removed by an etching process to expose the conductive layers 118A and 118B. In addition, another portion of the dielectric material layer 161 on the interconnect layer 132 may also be removed by this etching process to form a dielectric film 160 and expose the bonding pad 154 located on the scribe line SL. Additionally, a portion of the vent / hole 140 may be filled with the dielectric film 160 to complete the Figure 2A micro-electromechanical package 100 is provided.

[0030] Figure 8 , Fig. 9 and Fig.10 1 is a cross-sectional schematic diagram of some intermediate stages of a method for manufacturing a micro-electromechanical system package 100 according to another embodiment of the present invention. Figure 8 In step S201, a support wafer 110 is first provided, and a first cavity 112 and a second cavity 114 are formed in the support wafer 110. Then, a bonding layer 116 is sequentially deposited on the support wafer 110 and in the first cavity 112 and the second cavity 114 to wrap the support wafer 110. After that, a component wafer 120 is provided, and the component wafer 120 is bonded to the support wafer 110 to cover the first cavity 112 and the second cavity 114. Figure 8 As shown, the element wafer 120 includes a first element substrate 120A having a first MEMS element 122, a second element substrate 120B having a second MEMS element 122, a first bonding seal ring 125A corresponding to the first MEMS element 122, a second bonding seal ring 125B corresponding to the second MEMS element 124, and a portion 120P of the element wafer 120 located between two pre-cut lines 151 and 152. In addition, a bonding material 126 is formed on the first bonding seal ring 125A and the second bonding seal ring 125B.

[0031] In this embodiment, in step S201, the following is formed: Figure 3 The hole 142 shown vertically passes through the bonding material 126 and the second bonding seal ring 125B, and further extends to vertically pass through the second element substrate 120B, thereby exposing a portion of the bonding layer 116. In addition, the pre-cut lines 151 and 152, the grooves of both the first MEMS element 122 and the second MEMS element 124, and the hole 142 can be formed simultaneously by the same etching process, such as a deep reactive ion etching (DRIE) process. Other details of step S201 can be referred to the aforementioned Figure 5 The description of step S101 in will not be repeated here.

[0032] Still reading Figure 8In step S202, by using a vapor hydrofluoric acid (VHF) etching process, some portions of the bonding layer 116 in the first cavity 112 and the second cavity 114 and between the element wafer 120 and the support wafer 110 are removed through the grooves of both the first MEMS element 122 and the second MEMS element 124 and the pre-cut lines 151 and 152. In addition, a portion of the bonding layer 116 between the second element substrate 120B and the support wafer 110 can also be removed through the hole 142 by using this VHF etching process to form a vent hole 140, which is connected to the second cavity 114 and the hole 142.

[0033] Next, see Fig. 9 In step S203, the bonded support wafer 110 and the element wafer 120 are turned upside down, wherein the first cavity 112 is located directly above the first MEMS element 122, and the second cavity 114 is located directly above the second MEMS element 124. Then, a wafer 130 is provided, on which an interconnection layer 132 is formed, and under a first pressure P1, the element wafer 120 is bonded to the interconnection layer 132 on the wafer 130 through a bonding material 126. Afterwards, a vent hole 140 is formed in the second bonding layer 116B, and in subsequent processes, the vent hole 140 can be used to adjust the pressure in the second cavity 114. For other details of step S203, please refer to the aforementioned Figure 5 The description of step S103 is not repeated here.

[0034] Then, see Fig.10 In step S205, a portion of the support wafer 110 and a portion 120P of the device wafer 120 located between the two pre-cut lines 151 and 152 on the scribe line SL are removed by a dicing process, so that the vent hole 140 is exposed to the ambient pressure, and the hole 142 in both the second bonding seal ring 125B and the second device substrate 120B and the second cavity 114 are also exposed to the ambient pressure. In addition, in step S205, the first cavity 112 directly above the first MEMS element 122 is still maintained at the first pressure P1 in step S203. In this embodiment, the vent hole 140 can be used to adjust the pressure in the second cavity 114 to a desired vacuum degree, so that the second cavity 114 has a second pressure P2, which is different from the first pressure P1 in the first cavity 112. In addition, in some embodiments, during step S205, the anti-adhesion coating 145 can be deposited on the second device substrate 120B through the vent hole 140 to wrap the second MEMS element 124. For other details of step S205, please refer to the aforementioned Figure 6 The description of step S105 in will not be repeated here.

[0035] In addition, in this embodiment, if Figure 3 As shown, since the pre-cut line 152 has a protruding portion 152P corresponding to the position of the hole 142, after the cutting process in step S205, the second support substrate 110B and the second element substrate 120B can be formed as shown in FIG. Fig.10 The step structure 150 is shown in the cross-sectional schematic diagram, and the vent hole 140 is located in the step structure 150.

[0036] Next, refer to Fig.10 , in step S207, a dielectric material layer 161 is deposited on the platform of the step structure 150 to reseal the vent 140 at the second pressure P2. In addition, the dielectric material layer 161 may also be deposited on the interconnect layer 132 and located around the first bonding seal ring 125A and the second bonding seal ring 125B. At the same time, the dielectric material layer 161 may also be deposited on the conductive layers 118A and 118B. In some embodiments, the dielectric material layer 161 may be formed by a blanket deposition process, such as a CVD, PVD, or ALD process, and the composition of the dielectric material layer 161 may be, for example, silicon oxide. Then, a portion of the dielectric material layer 161 located on the conductive layers 118A and 118B may be removed by an etching process to expose the conductive layers 118A and 118B. In addition, another portion of the dielectric material layer 161 on the interconnect layer 132 may also be removed by this etching process to form a dielectric film 160 and expose the bonding pad 154 on the scribe line SL. In addition, a portion of the dielectric material layer 161 on the platform of the step structure 150 can be removed by the etching process to form a sealing layer 170, and the sealing layer 170 fills the vent hole 140 to complete the Figure 4 A micro-electromechanical package 100 is provided.

[0037] According to an embodiment of the present invention, a micro-electromechanical package includes various MEMS elements packaged under different pressures. In some embodiments, the MEMS package may include an inertial measurement unit (IMU), and the inertial measurement unit may include a first MEMS element such as a gyroscope, and a second MEMS element such as an accelerometer, the first MEMS element and the second MEMS element requiring different vacuum degrees and different anti-adhesion requirements, and integrated on the same chip. In one embodiment, one or more vents may be provided to laterally pass through the second bonding seal ring, and the vents are connected to the second cavity to adjust the pressure in the second cavity, and the height of these vents is substantially the same as the thickness of the second bonding seal ring. In another embodiment, one or more vents may be formed in the second bonding layer between the second element substrate and the second support substrate, and the vents are connected to the second cavity body to adjust the pressure in the second cavity, and the height of these vents is substantially the same as the thickness of the second bonding layer. According to an embodiment of the present invention, after the element wafer is bonded to the support wafer and the CMOS wafer, the second pressure in the second cavity can be adjusted through the vents so that the second pressure is different from the first pressure in the first cavity.

[0038] In addition, during the process step of adjusting the pressure in the second cavity, an anti-adhesion coating can be formed on the second MEMS element through the vent. In addition, the micro-electromechanical package can also include a platform structure outside the vent, and by depositing a dielectric film on the platform structure, the vent with a smaller height can be easily re-sealed, thereby improving the reliability of sealing the vent. Therefore, the micro-electromechanical package of the present invention can adjust the pressure in different cavities after bonding, and form an anti-adhesion coating on different MEMS elements after bonding, so that the packaging process of the micro-electromechanical package containing various MEMS elements with different cavity pressures is simplified, and the footprint of the micro-electromechanical package can also be reduced. The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the claims of the present invention should fall within the scope of the present invention.

Claims

1. A micro-electromechanical package, characterized in that: include: One wafer; an interconnect layer disposed on the wafer; a first component substrate, including a first micro-electromechanical component, and disposed on the wafer; a second component substrate, including a second micro-electromechanical component, laterally spaced from the first component substrate and disposed on the wafer; a first bonding sealing ring, disposed below the first component substrate and bonded to the interconnection layer; a second bonding seal ring, disposed below the second component substrate and bonded to the interconnect layer; a first supporting substrate, comprising a first cavity and bonded to the first component substrate; a second supporting substrate, comprising a second cavity and bonded to the second component substrate; a hole disposed in the second bonding sealing ring; and a dielectric film disposed on the interconnect layer and adjacent to the first bonding seal ring and the second bonding seal ring; The first cavity has a first pressure, the second cavity has a second pressure, and the second pressure is different from the first pressure.

2. The micro-electromechanical package according to claim 1, wherein: The hole laterally passes through the second bonding seal ring and is connected to the second cavity to serve as a vent hole, and a portion of the vent hole is filled with the dielectric film.

3. The micro-electromechanical package according to claim 2, characterized in that: The height of the vent hole is the same as the thickness of the second bonding sealing ring, and the width of the vent hole is between 1 micrometer and 100 micrometers.

4. The micro-electromechanical package according to claim 1, wherein: The first micro-electromechanical component includes a gyroscope, the second micro-electromechanical component includes an accelerometer, and the second pressure is greater than the first pressure.

5. The micro-electromechanical package according to claim 1, wherein: It also includes an anti-adhesion coating, which is disposed on the second component substrate in a forward direction.

6. The micro-electromechanical package according to claim 1, wherein: It also includes a first bonding layer, which is arranged between the first component substrate and the first supporting substrate, and a second bonding layer, which is arranged between the second component substrate and the second supporting substrate.

7. The micro-electromechanical package according to claim 6, characterized in that: The hole vertically passes through the second bonding seal ring and extends through the second component substrate.

8. The micro-electromechanical package according to claim 7, characterized in that: It also includes a vent hole disposed in the second bonding layer, the vent hole extending laterally between the second element substrate and the second supporting substrate, and the vent hole is connected to the second cavity and the hole.

9. The micro-electromechanical package according to claim 8, characterized in that: The second element substrate and the second supporting substrate form a step structure, and the vent hole is located in the step structure.

10. The micro-electromechanical package according to claim 9, characterized in that: A sealing layer is also included to fill a portion of the vent hole, and the sealing layer is on the step structure.

11. A method for manufacturing a micro-electromechanical system package, characterized in that: include: Providing a support wafer, including forming a first cavity and a second cavity in the support wafer; A component wafer is provided, comprising: forming a first micro-electromechanical element and a second micro-electromechanical element laterally separated from each other in the element wafer; forming a first bonding sealing ring and a second bonding sealing ring corresponding to the first micro-electromechanical element and the second micro-electromechanical element respectively; forming a hole in the second bonding seal ring; and forming two pre-cutting lines in the component wafer and located between the first micro-electromechanical component and the second micro-electromechanical component; Bonding the support wafer to the component wafer, wherein the first cavity is located directly above the first micro-electro-mechanical component, and the second cavity is located directly above the second micro-electro-mechanical component; Providing a wafer, including forming an interconnect layer on the wafer; bonding the component wafer to the interconnect layer on the wafer under a first pressure; removing a portion of the support wafer and a portion of the device wafer between the two pre-cut lines to expose the hole in the second bonding seal ring to an ambient pressure; and A dielectric film is formed on the interconnect layer.

12. The method for manufacturing a micro-electromechanical system package according to claim 11, characterized in that: The hole laterally passes through the second bonding seal ring and is connected to the second cavity to serve as a vent hole, and the vent hole is resealed by the dielectric film under a second pressure, which is different from the first pressure.

13. The method for manufacturing a micro-electromechanical system package according to claim 12, characterized in that: The method also includes sequentially depositing an anti-adhesion coating on the second micro-electromechanical component through the vent hole.

14. The method for manufacturing a micro-electromechanical system package according to claim 11, characterized in that: Forming the dielectric film includes: Depositing a dielectric material layer on the interconnect layer, wherein the dielectric material layer is located around the first bonding seal ring and the second bonding seal ring; and A portion of the dielectric material layer on the interconnect layer is removed to expose a bonding pad.

15. The method for manufacturing a micro-electromechanical system package according to claim 11, wherein: The method also includes forming a bonding layer between the support wafer and the component wafer.

16. The method for manufacturing a micro-electromechanical system package according to claim 15, characterized in that: The hole vertically passes through the second bonding seal ring and further extends to pass through the device wafer.

17. The method for manufacturing a micro-electromechanical system package according to claim 16, wherein: Before bonding the component wafer to the interconnect layer on the wafer, the method further includes removing a portion of the bonding layer between the support wafer and the component wafer through the hole to form a vent hole connected to the second cavity and the hole.

18. The method for manufacturing a micro-electromechanical system package according to claim 17, characterized in that: When viewed from above, one of the two pre-cutting lines has a protruding portion corresponding to the hole in the second bonding sealing ring, and after removing the portion of the support wafer and the portion of the component wafer located between the two pre-cutting lines, a first component substrate including the first microelectromechanical component, a second component substrate including the second microelectromechanical component, a first supporting substrate located directly above the first microelectromechanical component, and a second supporting substrate located directly above the second microelectromechanical component are formed, and the second supporting substrate and the second component substrate form a step structure, and the vent is located in the step structure.

19. The method for manufacturing a micro-electromechanical system package according to claim 17, wherein: Forming the dielectric film includes: Depositing a dielectric material layer on the interconnect layer, around the first bonding seal ring and the second bonding seal ring, and the dielectric material layer is also deposited on the step structure to seal the vent hole at a second pressure different from the first pressure; removing a portion of the dielectric material layer on the interconnect layer to expose a bonding pad; and Another portion of the dielectric material layer on the step structure is removed to form a sealing layer filling a portion of the vent hole.

20. The method for manufacturing a micro-electromechanical system package according to claim 17, wherein: The method also includes sequentially depositing an anti-adhesion coating on the second micro-electromechanical element through the vent hole.

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