Packaging assembly of pressure sensor

Abstract

The utility model discloses a packaging assembly of a pressure sensor. The packaging assembly comprises a packaging housing. The packaging shell is provided with at least two cavities which are not communicated with each other, the cavities comprise a first cavity and a second cavity, a pressure chip is fixedly arranged in the first cavity, and a second chip is fixedly arranged in the second cavity; the first cavity is provided with a first mounting port, the pressure chip is accommodated in the first cavity through the first mounting port, the second cavity is provided with a second mounting port, and the second chip is accommodated in the second cavity through the second mounting port; an air hole is formed in the bottom or the side wall of the first cavity and corresponds to a detection opening of the pressure chip. The special packaging structure is adopted, corrosion resistance is achieved, reliability is good, and detection is convenient.

Description

Technical Field

[0001] This utility model relates to the field of pressure sensors, and more particularly to a pressure sensor packaging component. Background Technology

[0002] With the development of social intelligence, the application fields of pressure sensors are becoming wider and wider, and the demand is increasing. Existing automotive pressure sensors are problematic because the automotive pressure environment is complex, and the measured media are often corrosive and conductive. Corrosive media can easily penetrate the gel and damage the circuit components, especially the IC chip. If multiple chips are packaged, it is impossible to determine which chip is faulty, which greatly reduces the long-term reliability of the pressure sensor.

[0003] Most pressure sensors on the market are fixed and electrically connected by solder paste. This means that the pressure sensor will inevitably be exposed to high temperatures. High temperatures can cause changes in the internal stress of the packaging material, which can lead to performance drift of the pressure sensor. This is especially true for micro pressure sensors, which are more sensitive to packaging.

[0004] Meanwhile, pressure sensors currently on the market are not compatible with the packaging of differential pressure chips and absolute pressure chips.

[0005] Therefore, considering the aforementioned technical problems, it is necessary to propose a new technical solution. Utility Model Content

[0006] To address at least one of the technical problems existing in the prior art, this utility model proposes a pressure sensor packaging assembly that is corrosion-resistant, has high reliability, and is easy to detect. The specific technical solution is as follows:

[0007] This utility model provides a packaging assembly for a pressure sensor, including a packaging housing;

[0008] The packaging shell has at least a first cavity and a second cavity that are not interconnected. A pressure chip is fixedly disposed in the first cavity and a second chip is fixedly disposed in the second cavity.

[0009] The first cavity has a first mounting port, through which the pressure chip is housed in the first cavity; the second cavity has a second mounting port, through which the second chip is housed in the second cavity.

[0010] The bottom or side wall of the first cavity is provided with air holes, which correspond to the detection ports of the pressure chip;

[0011] The bottom or side wall of the first cavity is provided with a first pad, and the pressure chip is connected to the first pad by flip-chip contact or wire bonding.

[0012] As a preferred embodiment of this utility model, a sealing ring is provided on the surface of the encapsulation shell, and the air hole is located inside the sealing ring.

[0013] As a preferred embodiment of this utility model, the second chip is an IC chip;

[0014] The package housing has application-side pins, and both the pressure chip and the second chip are electrically connected to the application-side pins directly or indirectly through pads inside the package housing.

[0015] As a preferred embodiment of this utility model, a first circuit adapter board is further provided in the first cavity, and a first solder pad is provided at the bottom or side wall of the first cavity. The first circuit adapter board is electrically connected to the first solder pad, and the pressure chip is electrically connected to the first circuit adapter board by flip-chip contact or wire bonding.

[0016] As a preferred embodiment of this utility model, a second circuit adapter board is further provided in the second cavity, and a second pad is provided at the bottom or side wall of the second cavity. The second circuit adapter board is electrically connected to the second pad, and the second chip is electrically connected to the second circuit adapter board.

[0017] As a preferred embodiment of this utility model, the packaging shell is further provided with a detection end pin. One end of the detection end pin extends into the first cavity or extends into the first cavity through a circuit and is electrically connected to the pressure chip, while the other end of the detection end pin extends out of the packaging shell.

[0018] As a preferred embodiment of this utility model, after at least the pressure chip is installed in the first cavity, depending on different application requirements, a first potting structure can be filled into the remaining space in the first cavity, a first protective cover can be placed on the first mounting port, or neither potting nor the first protective cover can be placed. Specifically, after at least the pressure chip is installed in the first cavity, the first potting structure is filled into the remaining space in the first cavity; or after at least the pressure chip is installed in the first cavity, the first protective cover is placed on the first mounting port of the first cavity; or after the pressure chip is installed in the first cavity, no potting is done in the first cavity, and the first protective cover is not placed on the first mounting port.

[0019] Further preferably, the first potting structure is a soft jelly-like silicone.

[0020] As a preferred embodiment of this utility model, after at least the second chip is installed in the second cavity, a second potting structure is filled into the remaining space in the second cavity; or after at least the second chip is installed in the second cavity, a second protective cover is placed on the second mounting port; or after at least the second chip is installed in the second cavity, a second potting structure is filled into the remaining space in the second cavity, and a second protective cover is placed on the second mounting port.

[0021] More preferably, the second potting structure is a rigid epoxy adhesive or a polyurethane adhesive.

[0022] As a preferred embodiment of this utility model, an annular sealing structure is provided between the first circuit adapter board and the first cavity, and the annular sealing structure is arranged around the periphery of the air hole.

[0023] As a preferred embodiment of this utility model, the pressure chip is an absolute pressure chip that is pressurized on the back, and a first protective cover can be placed on the first mounting port.

[0024] As a preferred embodiment of this utility model, the package housing is also provided with application terminal pins, and the pressure chip and the second chip are both electrically connected to the application terminal pins indirectly or directly.

[0025] As a preferred embodiment of this utility model, a sealing groove is provided on the inner wall of the first cavity, and the air hole is accommodated in the sealing groove.

[0026] As a preferred embodiment of this utility model, the bottom of the second cavity is provided with a through hole for the medium to be measured, and the back of the IC chip is configured to contact the medium to be measured in order to sense the temperature of the medium.

[0027] Compared with the prior art, the present invention has at least the following beneficial effects:

[0028] This patent uses multiple cavities for separate packaging, with the pressure chip and the second chip packaged separately in two cavities. The IC cavity is protected by a reliable hard adhesive and a second protective cover.

[0029] The packaging structure is flexible and versatile, capable of packaging differential pressure chips, gauge pressure chips, and absolute pressure chips, while being compatible with the packaging and application of differential pressure, gauge pressure, and absolute pressure chips.

[0030] The application-side pins of the package can be connected by laser welding or wire bonding, eliminating the need for a reflow soldering thermal process. This does not affect the performance of the pressure chip, especially the micro differential pressure chip, thus increasing product reliability.

[0031] A sealing ring is installed for sealing, which facilitates the assembly and sealing of the product and the module housing. This ensures that the pressure of the medium on the side will not leak, and also protects the circuit structure inside the cavity.

[0032] By setting up the detection pins, the signal from the pressure chip can be read directly, allowing for direct detection and troubleshooting of the pressure chip, and enabling a direct assessment of whether there is a problem with the pressure chip.

[0033] Setting up a first potting structure and a second potting structure can effectively protect the circuit structure of the chip.

[0034] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0035] To more clearly illustrate the technical solution of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a three-dimensional structural diagram of the packaging shell described in this utility model;

[0037] Figure 2 This is a top view of the packaging shell of the present invention;

[0038] Figure 3 This is a bottom view of the packaging shell of the present invention;

[0039] Figure 4 This is a cross-sectional three-dimensional structural diagram of the packaging shell described in this utility model;

[0040] Figure 5 This is a cross-sectional perspective view of the packaging assembly of the pressure sensor described in this utility model.

[0041] Among them, 1-encapsulation shell, 3-pressure chip, 4-second chip, 5-first circuit adapter board, 6-second circuit adapter board, 11-first cavity, 111-first mounting port, 112-vent, 113-first pad, 115-first protective cover, 116-sealing groove, 12-second cavity, 121-second mounting port, 122-through hole, 123-second pad, 125-second protective cover, 13-sealing ring, 71-application pin, 72-detection pin. Detailed Implementation

[0042] The embodiments of this utility model are described in detail below, providing a comprehensive overview and complete description of their technical solutions. It is clear that the described embodiments are merely a portion, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0043] Please see Figures 1-5 ,like Figure 1-5 As shown, this utility model provides a pressure sensor packaging assembly, including a packaging housing 1;

[0044] The packaging shell 1 has at least a first cavity 11 and a second cavity 12 that are not interconnected. A pressure chip 3 is fixedly disposed in the first cavity 11, and a second chip 4 is fixedly disposed in the second cavity 12.

[0045] The first cavity 11 has a first mounting port 111, through which the pressure chip 3 is housed in the first cavity 11. The second cavity 12 has a second mounting port 121, through which the second chip 4 is housed in the second cavity 12.

[0046] The bottom or side wall of the first cavity 11 is provided with an air hole 112, which corresponds to the detection port of the pressure chip 3.

[0047] The bottom or side wall of the first cavity 11 is provided with a first pad 113, and the pressure chip 3 is connected to the first pad 113 by flip-chip contact or wire bonding.

[0048] This patent uses multiple cavities for separate packaging, with the pressure chip and the second chip packaged separately in two cavities. The IC cavity is protected by a reliable hard adhesive and a second protective cover.

[0049] In this example, the housing 1 is a plastic housing. In this example, the pressure chip 3 is a MEMS pressure sensor chip.

[0050] Preferably, the second chip 4 is an IC chip, but this patent is not limited to this and can also be other types of chips. In the example, the second chip 4 is an IC chip, and a through hole 122 for the measured medium is opened at the bottom or side wall of the second cavity 12 so that the back of the IC chip can directly sense the temperature of the measured medium, and the pressure measurement after IC calibration is more accurate. The through hole (122) is set at an appropriate position at the bottom of the second cavity. More preferably, the vent 112 and the through hole 122 are set on the same surface of the package housing 1. In the example, the second mounting port 121 is covered with a second protective cover 125. In the example, the vent 112 is opened at the bottom of the second cavity (12).

[0051] Preferably, the first mounting port 111 and the second mounting port 121 are located on the same surface of the encapsulation housing 1.

[0052] In a preferred embodiment, a sealing ring 13 is provided on the surface of the packaging housing 1, and an air hole 112 is located within the sealing ring 13. In the example, both the air hole 112 and the through hole 122 are located within the sealing ring 13. In the example, the sealing ring 13 is integrally connected to the packaging housing 1, but this patent is not limited to this.

[0053] A sealing ring is installed for sealing, which facilitates the assembly and sealing of the product and the module housing. This ensures that the pressure of the medium on the side will not leak, and also protects the circuit structure inside the cavity.

[0054] As an example, the pressure chip 3 is an absolute pressure chip, including a back-pressure absolute pressure chip and a front-pressure absolute pressure chip. The pressure-bearing surface of the absolute pressure chip faces the inner wall of the first cavity 11 where the air hole is opened. In a specific example, the pressure chip 3 is a back-pressure absolute pressure chip developed by our company. For details of the back-pressure absolute pressure chip, please refer to patent ZL202223083619.2.

[0055] As an example, pressure chip 3 is a differential pressure chip.

[0056] In a preferred embodiment, a first pad 113 is provided at the bottom or side wall of the first cavity 11, and the pressure chip 3 is connected to the first pad 113 by flip-chip contact or wire bonding.

[0057] The pressure chip uses flip-chip contact or wire bonding electrical connections, which will not affect the performance of the pressure chip and increase the reliability of the product.

[0058] Further preferably, a first circuit adapter board 5 is also provided inside the first cavity 11, and a first solder pad 113 is provided on the bottom or side wall of the first cavity 11. The first circuit adapter board 5 is electrically connected to the first solder pad 113, and the pressure chip 3 is electrically connected to the first circuit adapter board 5 by flip-chip contact or wire bonding. In the example, the first circuit adapter board 5 is a MEMS circuit adapter board. In the example, the first solder pad 113 is located at the bottom of the first cavity 11, but this patent is not limited to this. In the example, the first circuit adapter board 5 is fixedly disposed inside the first cavity 11.

[0059] Specifically, the first circuit adapter board 5 is glued to the bottom of the first cavity 11. The first circuit adapter board 5 is electrically connected to the first pad 113 inside the first cavity 11 via gold wire bonding. The pressure chip 3 is mounted on the first circuit adapter board 5, although it can also be glued to the first circuit adapter board 5. Specifically, the pressure chip 3 and the first circuit adapter board 5 are electrically connected via gold wire bonding using either flip-chip contact or wire bonding. In this example, the first circuit adapter board 5 and the first pad 113 inside the first cavity 11 can be electrically connected via reflow solder paste soldering with gold wire bonding, or via flip-chip contact or wire bonding.

[0060] Further preferably, the first cavity 11 also includes a first potting structure (not shown in the figure). After at least the pressure chip is installed in the first cavity 11, the first potting structure is filled into the remaining space in the first cavity. Alternatively, in another preferred embodiment, after at least the pressure chip is installed in the first cavity 11, a first protective cover 115 is placed over the first mounting port 111 of the first cavity 11. Alternatively, in another preferred embodiment, after at least the pressure chip is installed in the first cavity 11, no potting is done in the first cavity, and the first protective cover 115 is not placed over the first mounting port 111. In the example, the first circuit adapter board 5 is fixedly installed and electrically connected in the first cavity 11, and then the pressure chip 3 is fixedly installed and electrically connected before the first potting structure is filled into the remaining space in the first cavity 11, and the first protective cover 115 is not placed over the first mounting port 111. In the example, the first potting structure is soft jelly silicone.

[0061] In one scenario, if the pressure chip 3 is an absolute pressure chip, then after setting the first potting structure, the first protective cover 115 is placed over the first mounting port 111. In another scenario, if the pressure chip 3 is a differential pressure chip, then after setting the first potting structure, the first mounting port 111 may or may not be covered with a protective cover. Of course, the first potting structure may not be installed in the first cavity, and after the pressure chip is installed, the first mounting port 111 may or may not be covered with a protective cover. The packaging structure is flexible and versatile, allowing for the packaging of differential pressure chips, gauge pressure chips, and absolute pressure chips, while simultaneously being compatible with the packaging and application of differential pressure, gauge pressure, and absolute pressure chips.

[0062] In a preferred embodiment, a second pad 123 is provided at the bottom or side wall of the second cavity 12, and the second chip 4 is electrically connected to the second pad 123.

[0063] Further preferably, a second circuit adapter board 6 is also provided inside the second cavity 12, and a second solder pad 123 is provided on the bottom or side wall of the second cavity 12. The second circuit adapter board 6 is electrically connected to the second solder pad 123, and the second chip 4 is electrically connected to the second circuit adapter board 6. In this example, the second solder pad 123 is provided on the bottom of the second cavity 12, but this patent is not limited to this. In this example, the second circuit adapter board 6 is fixedly disposed inside the second cavity 12.

[0064] Specifically, the second circuit adapter board 6 is glued to the bottom of the second cavity 12. The second circuit adapter board 6 is electrically connected to the second pad 123 inside the second cavity 12 via gold wire bonding. The second chip 4 is mounted on the second circuit adapter board 6. In this example, the second circuit adapter board 6 and the second pad 123 inside the second cavity 12 can be electrically connected via reflow solder paste soldering gold wire bonding, or via flip-chip contact or wire bonding. In this example, the second chip 4 and the second circuit adapter board 6 can be electrically connected via reflow solder paste soldering gold wire bonding, or via flip-chip contact or wire bonding.

[0065] Further preferably, the second cavity 12 also includes a second potting structure (not shown in the figure). After at least the second chip is installed in the second cavity 12, the remaining space in the second cavity 12 is filled with the second potting structure. Alternatively, in another preferred embodiment, after at least the second chip is installed in the second cavity 12, the second protective cover 125 is placed over the second mounting port 121. Alternatively, in another preferred embodiment, after at least the second chip is installed in the second cavity 12, the remaining space in the second cavity 12 is filled with the second potting structure, and the second protective cover 125 is placed over the second mounting port 121. In the example, the second circuit adapter board 6 is fixedly installed and electrically connected in the second cavity 12, and then the second chip 4 is fixedly installed and electrically connected before the second potting structure is filled into the second cavity 12, and then the second protective cover 125 is placed over the second mounting port 121. In the example, the second potting structure is rigid epoxy or polyurethane adhesive.

[0066] Setting up a first potting structure and a second potting structure can effectively protect the circuit structure of the chip.

[0067] In a preferred embodiment, the package housing 1 is further provided with an application terminal pin 71, to which the pressure chip 3 and the second chip 4 are electrically connected directly or indirectly. In the example, one end of the application terminal pin 71 extends into the second cavity 12 or, through a circuit, into the first cavity 11. The pressure chip 3 and the second chip 4 are electrically connected to one end of the application terminal pin 71 through a circuit, while the other end of the application terminal pin 71 extends outside the package housing 1. The application terminal pin of this patented package can be connected by laser welding or wire bonding, eliminating the need for a reflow soldering thermal process and preventing any impact on the performance of the pressure chip, especially the differential pressure chip, thus increasing product reliability.

[0068] Further preferably, it also includes a detection pin 72, one end of which extends into the first cavity 11 or through a circuit into the first cavity 11 and is electrically connected to the first pad 113, which is then electrically connected to the pressure chip 3, and the other end of the detection pin 72 extends out of the package housing 1.

[0069] By setting up the detection pins, the signal from the pressure chip can be read directly, allowing for direct detection and troubleshooting of the pressure chip, and enabling a direct assessment of whether there is a problem with the pressure chip.

[0070] In the example, the application pin 71 and the detection pin 72 are symmetrically arranged on both sides of the package housing 1.

[0071] In a preferred embodiment, an annular sealing structure is provided between the first circuit adapter plate 5 and the first cavity 11, and the annular sealing structure is arranged around the periphery of the vent. In the example, the annular sealing structure is a ring of glue or solder paste sealed between the first circuit adapter plate 5 and the bottom of the first cavity 11 to protect the circuit structure inside the first cavity from the influence of the external environment of the vent. More preferably, a sealing groove 116 is formed on the inner wall of the first cavity 11, and the annular sealing structure is accommodated in the sealing groove 116.

[0072] It should be noted that, unless otherwise specified, the features in the above embodiments or embodiments described herein can be combined with each other arbitrarily.

[0073] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0074] Although embodiments of the present invention have been shown and described above, it is understood that these embodiments are exemplary, and it will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the present invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A packaging assembly for a pressure sensor, characterized in that, Includes the encapsulation housing (1); The encapsulation housing (1) has at least a first cavity (11) and a second cavity (12) that are not interconnected. A pressure chip (3) is fixedly disposed in the first cavity (11), and a second chip (4) is fixedly disposed in the second cavity (12). The first cavity (11) has a first mounting port (111), and the pressure chip (3) is housed in the first cavity (11) through the first mounting port (111). The second cavity (12) has a second mounting port (121), and the second chip (4) is housed in the second cavity (12) through the second mounting port (121). The bottom or side wall of the first cavity (11) is provided with an air hole (112), and the air hole (112) corresponds to the detection port of the pressure chip (3); The bottom or side wall of the first cavity (11) is provided with a first pad (113), and the pressure chip (3) and the first pad (113) are connected by flip-chip contact or wire bonding.

2. The packaging assembly of the pressure sensor according to claim 1, characterized in that, A sealing ring (13) is provided on the surface of the encapsulation housing (1), and the vent (112) is located inside the sealing ring (13).

3. The packaging assembly of the pressure sensor according to claim 1, characterized in that, The second chip (4) is an IC chip; The package housing (1) is provided with application terminal pins (71). The pressure chip (3) and the second chip (4) are electrically connected to the application terminal pins (71) directly or indirectly through the pads in the package housing.

4. The packaging assembly of the pressure sensor according to claim 1, characterized in that, The first cavity (11) is also provided with a first circuit adapter board (5), and the bottom or side wall of the first cavity (11) is provided with a first pad (113). The first circuit adapter board (5) is electrically connected to the first pad (113), and the pressure chip (3) is electrically connected to the first circuit adapter board (5) by flip-chip contact or wire bonding; and / or The second cavity (12) is also provided with a second circuit adapter board (6), and a second pad (123) is provided at the bottom or side wall of the second cavity (12). The second circuit adapter board (6) is electrically connected to the second pad (123), and the second chip (4) is electrically connected to the second circuit adapter board (6).

5. The packaging assembly of the pressure sensor according to claim 1 or 3, characterized in that, The package housing (1) is also provided with a detection pin (72). One end of the detection pin (72) extends into the first cavity (11) or through the circuit into the first cavity (11) and is electrically connected to the pressure chip (3). The other end of the detection pin (72) extends out of the package housing (1).

6. The packaging assembly of the pressure sensor according to claim 1 or 4, characterized in that, After at least one pressure chip is installed in the first cavity (11), the remaining space in the first cavity is filled with a first potting structure; or after at least one pressure chip is installed in the first cavity (11), a first protective cover (115) is placed over the first mounting port (111) of the first cavity (11); or after the pressure chip is installed in the first cavity (11), no potting is done in the first cavity, and the first protective cover (115) is not placed over the first mounting port (111); and / or After at least the second chip is installed in the second cavity (12), the remaining space in the second cavity (12) is filled with a second potting structure; or after at least the second chip is installed in the second cavity (12), a second protective cover (125) is placed on the second mounting port (121); or after at least the second chip is installed in the second cavity (12), a second potting structure is filled in the remaining space in the second cavity (12), and a second protective cover (125) is placed on the second mounting port (121).

7. The packaging assembly of the pressure sensor according to claim 6, characterized in that, The first potting structure is a soft, gel-like silicone; and / or The second potting structure is a rigid epoxy or polyurethane adhesive.

8. The packaging assembly of the pressure sensor according to claim 1, characterized in that, An annular sealing structure is provided between the first circuit adapter board (5) and the first cavity (11), and the annular sealing structure is arranged around the outside of the air hole.

9. The packaging assembly of the pressure sensor according to claim 6, characterized in that, The pressure chip (3) is an absolute pressure chip that is pressed on the back, and the first protective cover (115) is closed on the first mounting port (111).

10. The packaging assembly of the pressure sensor according to claim 8, characterized in that, The inner wall of the first cavity (11) is provided with a sealing groove (116), and the annular sealing structure is housed in the sealing groove (116).

11. The packaging assembly of the pressure sensor according to claim 3, characterized in that, The bottom of the second cavity (12) is provided with a through hole (122) for the medium to be measured. The back of the IC chip is configured to contact the medium to be measured in order to sense the temperature of the medium.

Images