Sensors and packaging components

Abstract

The present invention discloses a sensor packaging component, comprising: a redistribution layer, which comprises a first surface and a second surface opposite to each other; a first tube core, which is electrically connected to the first surface of the redistribution layer; a molding compound, which comprises a third surface and a fourth surface opposite to each other, the third surface of the molding compound being combined with the first surface of the redistribution layer; the molding compound encapsulating the first tube core on the first surface side of the redistribution layer; and a sensor element, which is electrically connected to the redistribution layer. The sensor packaging component allows more components to be packaged together, and provides better structural support or better heat distribution for the packaging component, while reducing the volume and cost of the entire packaging component.

Description

Technical Field

[0001] The present invention relates to sensor technology, and in particular to a sensor based on micro-electromechanical technology and a packaging component thereof. Background Art

[0002] MEMS (Micro Electro-Mechanical System) sensors are sensors manufactured using microelectronics and micromachining technology. Compared with traditional sensors, they are small in size, light in weight, low in cost, low in power consumption, high in reliability, suitable for mass production, easy to integrate and intelligent. At the same time, the characteristic size of the micron level enables it to perform functions that some traditional mechanical sensors cannot achieve. MEMS sensors are widely used in automobiles, portable consumer electronic devices and even in the medical field.

[0003] The packaging of MEMS sensors is a key factor in the design and manufacture of MEMS sensors. The packaging of MEMS sensors has special requirements. For example, the sensor needs to sense changes in the external environment and realize the function of electrical signal extraction. Therefore, it is necessary to retain a path directly connected to the outside world on the sensor shell to sense physical information such as light, heat, air pressure, and force. A typical example is a MEMS pressure sensor, which needs to have an opening in its shell to sense the external medium pressure. Traditional MEMS packaging includes chip packaging, device packaging, and system-level packaging. However, the current market demand requires more devices and functions to be integrated into smaller and smaller spaces. Existing packaging solutions are difficult to meet the demand for devices with higher component density. Summary of the invention

[0004] The purpose of the present invention is to solve the problem of large volume of sensors. According to an embodiment of the present invention, a sensor packaging assembly comprises:

[0005] a redistribution layer including a first surface and a second surface opposite to each other;

[0006] a first die electrically connected to the first side of the redistribution layer;

[0007] a molding material including a third side and a fourth side opposite to each other, the third side of the molding material being bonded to the first side of the redistribution layer; the molding material encapsulating the first die on the first side of the redistribution layer; and,

[0008] A sensing element is electrically connected to the redistribution layer.

[0009] Optionally, the sensor device further comprises a second die and a third die, the second die being electrically connected to the first side of the redistribution layer, the molding compound encapsulating the second die on the first side of the redistribution layer; the third die being electrically connected to the second side of the redistribution layer.

[0010] Optionally, the packaging component also includes a molded through-hole electrical connector, which passes through the third and fourth sides of the molding material and is connected to the redistribution layer; the fourth side of the molding material also includes a solder pad, and the redistribution layer is electrically connected to the solder pad through the molded through-hole electrical connector.

[0011] Optionally, the molding material further includes a side wall connecting the third surface and the fourth surface, and the pad extends along the fourth surface of the molding material to an outer surface of the side wall of the molding material.

[0012] Optionally, the packaging structure also includes a cover shell, which is installed on the second surface of the redistribution layer, and a first space is formed between the cover shell and the second surface of the redistribution layer, and the sensor element is located in the first space; the cover shell is provided with a first air vent connecting the first space with the outside world.

[0013] Optionally, the cover is adhered to the second surface of the redistribution layer.

[0014] Optionally, the packaging component further includes a gel filler which at least partially fills the first space; the gel filler covers the sensing element.

[0015] Optionally, a second space is formed between the sensing element and the second surface of the redistribution layer, which is airtightly isolated from the first space; the redistribution layer includes a second air permeability extending through the first and second surfaces of the redistribution layer; the molding material includes a third air permeability extending through the third and fourth surfaces of the molding material, the second air permeability and the third air permeability are interconnected, and the second space is connected to the outside through the second air permeability and the third air permeability.

[0016] Optionally, the sensor element is a MEMS pressure sensor element; and the first die is an ASIC.

[0017] According to another aspect of the present invention, a sensor is provided, which includes a packaging component of the sensor and a carrier substrate, wherein the packaging component of the sensor is mounted on the carrier substrate.

[0018] It can be seen from the above that the sensor packaging assembly according to the present invention allows more components to be packaged together by providing a redistribution layer and a molding compound, and provides better structural support and / or better heat distribution for the packaging assembly, while reducing the volume and cost of the entire packaging assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The features, characteristics, advantages and benefits of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

[0020] Figure 1 A schematic cross-sectional structure diagram of a sensor packaging assembly according to an embodiment of the present invention is shown.

[0021] Figure 2 A schematic cross-sectional structure diagram of a sensor packaging assembly according to another embodiment of the present invention is shown.

[0022] Figure 3 A schematic cross-sectional structure diagram of a sensor packaging assembly according to yet another embodiment of the present invention is shown.

[0023] Figure 4 A schematic cross-sectional structure diagram of a sensor packaging assembly according to another embodiment of the present invention is shown. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0025] Figure 1The cross-sectional structure of a sensor package component 100 according to an embodiment of the present invention is shown. As shown in the figure, the sensor package component 100 includes an RDL (Redistribution Layer) 11, a sensor element 12, a molding compound 13, a cover 14, and a first tube core 15, and optionally also includes a second tube core 16 and a third tube core 17. Among them, the RDL 11 includes a first surface 111 and a second surface 112 opposite to each other, the first tube core 15 and the second tube core 16 are electrically connected to the first surface 111 of the RDL 11, and the third tube core 17 is electrically connected to the second surface 112 of the RDL 11. The molding compound 13 encapsulates the first tube core 15 and the second tube core 16 on the first surface 111 side of the RDL 11. The molding compound 13 includes a third surface 131 and a fourth surface 132 opposite to each other. When the molding material 13 encapsulates the first tube core 15 and the second tube core 16 on the first surface 111 side of the RDL 11, the third surface 131 of the molding material 13 is combined with the first surface 111 of the RDL 11. In addition, the molding material 13 may also include a plurality of conductive pillars 19, which extend from the first surface 111 of the RDL 11 to the second surface 112 and penetrate the molding material 13. The cover 14 is installed on the second surface 112 of the RDL 11, and a first space 18 is formed between the cover 14 and the second surface 112 of the RDL 11. The cover 14 is provided with a first vent 141 connecting the first space 18 with the outside; the sensor element 12 is located in the first space 18 and is electrically connected to the second surface 112 of the RDL 11.

[0026] The RDL 11 includes a rewiring line 113 and a dielectric layer 114, and the rewiring line 113 may be one or more. In the present embodiment, the RDL 11 includes an embedded rewiring line 113. It can be formed, for example, by first forming a seed layer and then forming a metal (e.g., copper) pattern to generate the rewiring line 113. Optionally, the rewiring line 113 can also be formed by a deposition (e.g., sputtering) and etching process. The material of the rewiring line 113 may include, but is not limited to, metal materials such as copper, titanium, nickel, gold, and combinations or alloys thereof. The metal pattern of the rewiring line 113 is then embedded in the dielectric layer 114. The dielectric layer 114 can be any suitable dielectric material, such as an oxide or a polymer (e.g., polyimide). The exposed portion of the rewiring line 113 can be used for electrical connection of different dies. The RDL 11 can be formed by a layer-by-layer process and can be formed using thin film technology. In the present embodiment, the RDL 11 has a thickness thinner than that of a conventional organic or laminated substrate. For example, a conventional six-layer organic or laminated substrate has a thickness of 300μm–500μm. The thickness of RDL11 can be determined by the number and formation of the redistribution line 113 and the dielectric layer 114. In the present embodiment, the redistribution line 113 has a thickness of 3μm-10μm, and the dielectric layer 114 has a thickness of 2μm-5μm. The RDL 11 of the present embodiment also allows for a narrower line spacing width (fine spacing) and finer lines than conventional organic or laminated substrates. In the present embodiment, the RDL 11 has a total thickness of less than 50μm, for example 30μm-25μm. Or a thickness of less than 20μm, for example. In the present embodiment, the first side 111 of the RDL 11 is formed by the dielectric layer 114 to achieve passivation of the RDL 11.

[0027] refer to Figure 1 , the sensing element 12, the first die 15, the second die 16 and the third die 17 are electrically connected to the RDL 11. The type of the first die 15 may depend on the specific application. For example, the first die 15 may be a logic component (such as ASIC), a memory or other component, and different types of first dies 15 may be electrically connected to the RDL 11. The second die 16 and the third die 17 may be passive components such as capacitors or inductors. In the present embodiment, the first die 15 and the second die 16 are electrically connected to the first side 111 of the RDL 11 and to the redistribution line 113 to be electrically connected to the RDL 11. The sensing element 12 and the third die 17 are electrically connected to the second side 112 of the RDL 11.

[0028] Electrical connection can be achieved using a variety of technologies. For example, the first tube core 15 and the second tube core 16 can be achieved using the flip chip method. Specifically, the first tube core 15 and the second tube core 16 include a side with a contact pad (not shown in the figure) and another opposite side that does not include the contact pad. The side with the contact pad may also include a passivation layer surrounding the contact pad. The side with the contact pad of the first tube core 15 and the second tube core 16 is electrically connected to the first side 111 of the RDL 11. Further, the contact pads of the first tube core 15 and the second tube core 16 are electrically connected to the exposed part of the rewiring of the RDL 11 using conductive bumps such as welding materials. At the same time, the third tube core 17 can be electrically connected to the second side 112 of the RDL 11 using conductive bumps and non-conductive paste (NCP) or non-conductive film (NCF) that laterally surrounds the conductive bumps, and the electrical connection can be achieved by electrically connecting the conductive bumps to the exposed part of the rewiring of the RDL 11 from the second side 112 using thermal compression. The conductive bumps are formed by, for example, gold or welding materials.

[0029] The first tube die 15 and the second tube die 16 can then be encapsulated by the molding compound 13. The molding compound 13 is composed of, for example, a thermosetting cross-linked resin (e.g., epoxy resin), a liquid or particles, a sheet or a film. Suitable techniques can be used to achieve encapsulation of the first tube die 15 and the second tube die 16, such as compression molding, liquid encapsulant injection, and lamination. In this embodiment, the molding compound 13 is a continuous uniform composition layer that fills the first side 111 of the RDL 11 and encapsulates the first tube die 15 and the second tube die 16. Figure 1 As shown, the molding material 13 includes a third surface 131 and a fourth surface 132 opposite to each other. When the molding material 13 encapsulates the first die 15 and the second die 16 on the first surface 111 of the RDL 11, the third surface 131 of the molding material 13 contacts the first surface 111 of the RDL 11, and the lateral sides of the first die 15 and the second die 16 are sealed in the molding material 13. At the same time, the molding material 13 is also formed on the front surfaces 151 and 161 of the first die 15 and the second die 16 away from the first surface 111 of the RDL 11. It should be understood by those skilled in the art that it is not required that the front surfaces of the first die 15 and the second die 16 are sealed in the molding material 13. For example, in some other embodiments, the lateral sides of the first die 15 and the second die 16 are sealed in the molding material 13, but the molding material is not formed on the front surfaces of the first die 15 and the second die 16, that is, the front surfaces of the first die 15 and the second die 16 are exposed.

[0030] The molding material 13 includes at least one conductive pillar 19. In the present embodiment, the conductive pillar 19 is a TMV (Through Mold Via) electrical connector, which passes through the third side 131 and the fourth side 132 of the molding material 13 and connects the first side 111 of the RDL 11. Specifically, the TMV electrical connector is connected to a single or multiple redistribution lines of the RDL 11 to achieve electrical connection with the RDL 11. The TMV electrical connector can be formed on the molding material 13 in any suitable manner. Including drilling formation such as laser drilling. It is also possible to pre-set a columnar structure during the formation of the molding material 13 so that it is formed during the demolding process. After the TMV electrical connector is formed, it can be cleaned for subsequent processing. Cleaning may include any suitable operation, such as wet etching, plasma etching, or a combination thereof. The number of TMV electrical connectors is determined by the number of input and output (I / O) devices included on the RDL 11. By setting the TMV electrical connector, the signal output of the sensor package component 100 can be realized to other circuits, such as a PCB board as a carrier substrate of the sensor. As shown in the figure, a conductive filler is added to the TMV electrical connector, and the filler is a conductive sealing material or a metal such as copper. The filling can be achieved by any suitable operation to ensure proper electrical connection between the filler and the RDL 11. A pad 20 is also provided on the fourth side 132 of the molding material 13 at the TMV electrical connector. The TMV electrical connector is connected to the pad 20.

[0031] The cover 14 is mounted on the second surface 122 of the RDL 11. In this embodiment, the cover 14 is adhered to the second surface 112 of the RDL 11 by an adhesive. A conductive adhesive can be used to achieve good electromagnetic interference (EMI) shielding. The cover 14 is mounted on the second surface 112 of the RDL 11, and a first space 18 is formed between the cover 14 and the second surface 112 of the RDL 11. The sensor element 12 is located in the first space 18 and is electrically connected to the second surface 112 of the RDL 11. The cover 14 also includes a first vent 141 connecting the first space 18 with the outside.

[0032] The sensing element 12 may be electrically connected to the second surface 112 of the RDL 11 using a variety of electrical connection technologies, such as Figure 1 Wire bonding 25, flip chip method 27 or through silicon via (TSV) 26 as shown.

[0033] In the package assembly 100 of the sensor of the present embodiment, the sensing element 12 is a MEMS fluid pressure sensing element, which is used to measure the pressure of an external medium such as air or liquid. The first tube core 15 is an ASIC, which includes one or more circuits embedded in and / or on a substrate such as silicon, gallium arsenide, SiC (silicon carbide) graphene or any semiconductor material, which is configured to perform specific tasks or realize specific functions. Specifically, the external medium enters the first space 18 through the first air vent 141 connecting the first space 18 and the external space, and the sensing element 12 senses the pressure of the external medium. The first tube core 15, the second tube core 16 and the third tube core 17 electrically connected to the sensing element 12 on the RDL 11 convert the pressure of the external medium sensed by the sensing element 12 into an electrical signal and output it via the TMV 19.

[0034] At the same time, a protective member such as a gel filler 21 can also be used to protect the sensing element 12, so as to protect the normal operation of the sensing element 12 in a harsh working environment. The gel filler 21 at least partially fills the first space 18 and covers the sensing element 12. Further, it can also cover the second surface 112 of the RDL 11, and can even cover the third tube core 17 electrically connected to the second surface 112 of the RDL 11. The gel filler 21 has an electrical insulation property. The gel filler 21 is used to protect the sensing element 12 and the third tube core 17 from being affected by the introduced medium contaminants. Compared with a solution, the gel filler 21 is more of a colloidal material in a solid form. The gel filler 21 can isolate the fluid pressure sensing element 12 from the harsh surrounding environment, and can accurately transmit the pressure applied by the external medium to the sensing element 12.

[0035] Figure 2 FIG. 2 shows a cross-sectional structure of a sensor packaging component 200 according to a second embodiment of the present invention. Figure 1 , Figure 2 After forming the molding material 13, the conductive bump 22 can be attached to the molding material 13 or formed directly on the molding material 13. As shown in the figure, the conductive bump 22 is disposed at the molding through hole 19 on the fourth side 132 of the molding material 13. The conductive bump 22 can use a variety of structures, such as Figure 2 The conductive bumps 22 are configured to electrically connect the sensor package assembly to other circuits such as a carrier substrate.

[0036] Figure 3 FIG. 3 shows a cross-sectional structure of a sensor packaging component 300 according to a third embodiment of the present invention. Figure 1 , Figure 3In the packaging component 300 of the sensor, the TMV electrical connector 19 of the fourth side 132 of the molding material 13 also has a solder pad 20, which extends along the fourth side 132 of the molding material 13 to the outer surface of the side wall 133 of the molding material 13, and forms a tin creeping channel 23 that can be clearly seen by automatic optical inspection (AOI) in the transition area between the fourth side 132 and the outer surface of the side wall 133.

[0037] Figure 4 The cross-sectional structure of the package assembly 400 of the sensor according to the fourth embodiment of the present invention is shown. In this embodiment, when the sensor element 12 is mounted on the second surface 112 of the RDL 11, the sensor element forms a second space 24 which is airtightly isolated from the first space 18 on the side opposite to the second surface 112 of the redistribution layer. The RDL 11 is provided with a second vent 115 connecting the first surface 111 and the second surface 112 of the RDL 11, and the molding material 13 is provided with a third vent 134 connecting the third surface 131 and the fourth surface 132 of the molding material 13, and the second vent 115 and the third vent 134 are connected to each other. At the same time, the second vent 115 and the third vent 134 are connected to the second space 24 and the external medium. The sensor element 12 of this embodiment can also be used to measure the pressure of the external medium in the second space 24. Further, by cooperating with the first tube core 15 arranged on the first surface 111 of the RDL 11, the pressure of the external medium located in the first space 18 and the second space 24 can also be compared. For example, the pressure difference of the external medium located in the first space 18 and the second space 24 is compared.

[0038] The arrangement of RDL and molding compound can increase the expansion area of ​​the sensor packaging component, thereby allowing more components to be packaged together, and providing better structural support or providing better heat dissipation for the packaging component. At the same time, the coupling of RDL and molding compound also realizes the SIP (System in Package) packaging form. The SIP structure uses RDL to fan out the electrical terminals of the die and allows passive devices and / or covers to be packaged together, reducing the use of organic substrates, etc., thereby reducing the volume of the entire packaging component. At the same time, it also protects the packaging component and allows the sensor packaging component to contact the outside world.

[0039] The sensor package assembly of the present invention may also be packaged with other circuits such as a carrier substrate for the next level, thereby forming, for example, a MEMS pressure / differential pressure sensor.

[0040] Those skilled in the art can make various corresponding changes and modifications based on the above technical solutions and concepts, and all of these changes and modifications should be included in the protection scope of the claims of the present invention.

Claims

1. A packaging component of a sensor, characterized in that: It includes: a redistribution layer including a first surface and a second surface opposite to each other; a first die electrically connected to the first side of the redistribution layer; A molding material filled on the first surface side of the redistribution layer, the molding material comprising a third surface and a fourth surface opposite to each other, the third surface of the molding material being combined with the first surface of the redistribution layer; the molding material encapsulating the first tube core on the first surface side of the redistribution layer; the fourth surface of the molding material comprising a pad, the molding material comprising at least one electrical connector, the redistribution layer being electrically connected to the pad through the electrical connector; a sensing element electrically connected to the redistribution layer; as well as A cover is installed on the second surface of the redistribution layer, a first space is formed between the cover and the second surface of the redistribution layer, the sensor element is located in the first space, and the cover is provided with a first vent connecting the first space with the outside.

2. The packaging assembly according to claim 1, characterized in that: The packaging component also includes a second tube core and a third tube core, the second tube core is electrically connected to the first side of the redistribution layer, and the molding material encapsulates the second tube core on the first side of the redistribution layer; the third tube core is electrically connected to the second side of the redistribution layer.

3. The packaging assembly according to claim 1, characterized in that: The molding material is composed of a thermosetting cross-linked resin, a liquid or particles, a sheet or a film, and the electrical connector is a molded through-hole electrical connector, which passes through the third side and the fourth side of the molding material and is connected to the redistribution layer; the redistribution layer is electrically connected to the pad through the molded through-hole electrical connector.

4. The packaging assembly according to claim 3, characterized in that: The molding material is realized by using a suitable technique among compression molding, liquid encapsulant injection and lamination technology. The molding material further comprises a sidewall connecting the third surface and the fourth surface. The pad extends along the fourth surface of the molding material to the outer surface of the sidewall of the molding material.

5. The packaging assembly according to claim 1, characterized in that: The cover is adhered to the second surface of the redistribution layer, and the cover realizes electromagnetic interference shielding.

6. The packaging assembly according to claim 1, characterized in that: The packaging component further includes a gel filler which at least partially fills the first space; the gel filler covers the sensing element.

7. The packaging assembly according to claim 1, characterized in that: A second space which is airtightly isolated from the first space is formed between the sensor element and the second surface of the redistribution layer; the redistribution layer includes a second air permeability extending through the first surface and the second surface of the redistribution layer; the molding material includes a third air permeability extending through the third surface and the fourth surface of the molding material, the second air permeability and the third air permeability are interconnected, and the second space is connected to the outside through the second air permeability and the third air permeability.

8. The packaging assembly according to any one of claims 1 to 7, characterized in that: The sensor element is a MEMS pressure sensor element; the first tube die is an ASIC.

9. A micro-electromechanical system sensor, characterized in that: The sensor comprises a packaging component of the sensor according to any one of claims 1 to 8 and a carrier substrate, and the packaging component of the sensor is mounted on the carrier substrate.

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