Pressure chip and pressure sensor

Abstract

The invention discloses a pressure chip and a pressure sensor. The pressure chip comprises a substrate, a first conductive layer, a second conductive layer, a third conductive layer and a fourth conductive layer. The substrate comprises a first surface and a second surface which are opposite in the thickness direction, and a plurality of through holes extending from the first surface to the second surface. The first conducting layer and the third conducting layer are located on the same film layer and at least located in the through hole, and the second conducting layer and the fourth conducting layer are located on the side, away from the first surface, of the second surface. The first surface comprises a pressure sensing area and a passive device area which are not overlapped with each other. In the pressure sensing area, the first conductive layer and the second conductive layer form a pressure sensing structure; and in the passive device region, the third conductive layer and the fourth conductive layer form a passive device structure. And further miniaturization and cost reduction of the pressure sensor are facilitated.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a pressure chip and a pressure sensor. Background Art

[0002] With the continuous development of Internet of Things technology, the demand for the use of Microelectro Mechanical Systems (MEMS) sensors, which are key sensing components in the Internet of Things, is increasing. Among them, MEMS pressure sensors are mainly used to measure atmospheric pressure. When used in smart devices such as mobile phones, the altitude can be calculated by the air pressure at different heights, and accurate three-dimensional positioning can be performed in conjunction with satellite navigation systems. MEMS pressure sensors include a pressure chip and an application-specific integrated circuit (ASIC) chip. The pressure chip is connected and packaged on the ASIC chip through leads, wherein the pressure chip is used to generate capacitance / resistance changes when subjected to pressure, and the ASIC chip is used to convert the pressure signal into an electrical signal according to the change in capacitance / resistance, which is used to measure the pressure. A large number of passive components (capacitors, inductors, resistors, etc.) are scattered on the ASIC chip, resulting in a large overall size of the sensor, making it difficult to further miniaturize. Summary of the invention

[0003] The present invention provides a pressure chip and a pressure sensor, which are used to reduce the volume of the pressure sensor and lower the cost.

[0004] A first aspect of the present invention provides a pressure chip, comprising:

[0005] The substrate substrate comprises a first surface and a second surface opposite to each other in a thickness direction, and a plurality of through holes extending from the first surface to the second surface;

[0006] A first conductive layer and a third conductive layer; the first conductive layer and the third conductive layer are located in the same film layer and at least in the through hole;

[0007] A second conductive layer and a fourth conductive layer; the second conductive layer and the fourth conductive layer are located in the same film layer and are located on a side of the second surface facing away from the first surface;

[0008] The first surface includes a non-overlapping pressure sensing area and a passive device area; in the pressure sensing area, the first conductive layer and the second conductive layer form a pressure sensing structure; in the passive device area, the third conductive layer and the fourth conductive layer form a passive device structure.

[0009] In the pressure chip provided by the present invention, the material of the substrate is glass.

[0010] In the pressure chip provided by the present invention, the material of the second conductive layer and the material of the fourth conductive layer are both doped bulk silicon.

[0011] The pressure chip provided by the present invention also includes:

[0012] The glass cover is located on the side of the second conductive layer and the fourth conductive layer away from the base substrate; the orthographic projection of the glass cover on the base substrate covers the orthographic projection of the pressure sensing structure on the base substrate and the orthographic projection of the passive device structure on the base substrate.

[0013] The pressure chip provided by the present invention also includes:

[0014] The connecting pad is located on the side of the first surface facing away from the second surface; the pressure sensing structure and the passive device structure are electrically connected to the connecting pad; and the connecting pad is used to connect to the signal processing circuit to form a pressure sensor.

[0015] In the pressure chip provided by the present invention, in the pressure sensing area, the first conductive layer includes an opposing electrode, and the second conductive layer includes a sensing electrode; the orthographic projection of the opposing electrode on the base substrate is located within the orthographic projection of the sensing electrode on the base substrate; along the thickness direction of the base substrate, the opposing electrode and the sensing electrode are separated by a first set distance to form a pressure sensing structure;

[0016] The surface of the sensing electrode facing away from the substrate has a first cavity; the orthographic projection of the opposing electrode on the substrate is located within the orthographic projection of the bottom of the first cavity on the substrate; the thickness of the sensing electrode in the corresponding area of ​​the bottom of the first cavity is less than the thickness of the sensing electrode around the bottom of the first cavity;

[0017] The glass cover plate comprises a first through hole penetrating the glass cover plate in the thickness direction; the orthographic projection of the first through hole on the base substrate is located within the orthographic projection of the first cavity on the base substrate, so that the first cavity is connected with the external environment through the first through hole.

[0018] In the pressure chip provided by the present invention, the material of the first conductive layer and the material of the third conductive layer are both doped bulk silicon;

[0019] The through hole includes a second through hole and a third through hole that are spaced apart; the connecting pad includes a first connecting pad and a second connecting pad; wherein the first connecting pad is located at a position corresponding to the second through hole, and the second connecting pad is located at a position corresponding to the third through hole;

[0020] The second through hole and the third through hole are located in the pressure sensing area; the counter electrode is filled in the second through hole and is electrically connected to the first connection pad;

[0021] The first conductive layer also includes:

[0022] The first connection structure is located in the third through hole; one end of the first connection structure is electrically connected to the sensing electrode, and the other end of the first connection structure is electrically connected to the second connection pad.

[0023] In the pressure chip provided by the present invention, within the range covered by the orthographic projection of the sensing electrode on the substrate, the second surface is a plane;

[0024] The surface of the sensing electrode facing the base substrate has a second cavity; the second cavity is used to make the opposing electrode and the sensing electrode have a first set distance along the thickness direction of the base substrate; the orthographic projection of the second cavity on the base substrate coincides with the orthographic projection of the first cavity on the base substrate; the sensing electrodes around the second cavity are in contact with the second surface of the base substrate, so that a closed space is formed in the second cavity.

[0025] In the pressure chip provided by the present invention, the second surface of the substrate includes a first groove; the first groove is located within the positive projection of the sensing electrode on the substrate, and the positive projection of the bottom of the first cavity on the substrate is located in the area where the first groove is located; the second through hole is located in the first groove; the surface of the sensing electrode facing the substrate is a plane, and the first groove is used to make the opposing electrode and the sensing electrode separated by a first set distance along the thickness direction of the substrate; the sensing electrodes around the first groove are in contact with the second surface of the substrate to form a closed space in the first groove.

[0026] In the pressure chip provided by the present invention, the passive device structure includes an inductor structure;

[0027] The through holes further include a plurality of fourth through holes; the connecting pads further include a third connecting pad and a fourth connecting pad;

[0028] A plurality of fourth through holes are located in the passive device region;

[0029] The third conductive layer also includes:

[0030] A plurality of second connection structures are located in the fourth through hole;

[0031] The fourth conductive layer further comprises:

[0032] A plurality of first inductor leads are located on a side of the second surface facing away from the first surface and located in a passive device area;

[0033] The pressure chip also includes:

[0034] A fifth conductive layer is located on a side of the first surface away from the second surface; the material of the fifth conductive layer is metal; the fifth conductive layer includes a plurality of second inductor leads; the second inductor leads are located in the passive device area;

[0035] The second connection structure is used to connect the first inductor lead and the second inductor lead end to end to form an inductor structure; one end of the inductor structure is electrically connected to the third connection pad, and the other end is electrically connected to the fourth connection pad.

[0036] In the pressure chip provided by the present invention, the passive device structure includes a capacitor structure;

[0037] The through hole further includes a fifth through hole and a sixth through hole which are arranged at intervals; the connecting pad further includes a fifth connecting pad and a sixth connecting pad; wherein the fifth connecting pad is located at a position corresponding to the fifth through hole, and the sixth connecting pad is located at a position corresponding to the sixth through hole;

[0038] The fifth through hole and the sixth through hole are located in the passive device area;

[0039] The third conductive layer also includes:

[0040] A first electrode; the first electrode is located in the fifth through hole and is electrically connected to the fifth connection pad;

[0041] A third connecting structure is located in the sixth through hole;

[0042] The fourth conductive layer further includes: a second electrode located in the passive device region;

[0043] The orthographic projection of the second electrode on the base substrate covers the first electrode; along the thickness direction of the base substrate, the second electrode is separated from the first electrode by a second set distance to form a capacitor structure; one end of the third connection structure is electrically connected to the second electrode, and the other end is connected to the sixth connection pad.

[0044] In the pressure chip provided by the present invention, within the range covered by the orthographic projection of the second electrode on the substrate, the second surface is a plane;

[0045] The surface of the second electrode facing the substrate has a third cavity; the third cavity is used to make the second electrode and the first electrode have a second set distance along the thickness direction of the substrate; the orthographic projection of the third cavity on the substrate covers the fifth through hole; the second electrode around the third cavity contacts the second surface of the substrate, so that a closed space is formed in the third cavity; or,

[0046] The second surface of the base substrate also includes a second groove; the second groove is located within the positive projection of the second electrode on the base substrate; the fifth through hole is located in the second groove; the surface of the second electrode facing the base substrate is a plane, and the second groove is used to make the second electrode and the first electrode separated by a second set distance along the thickness direction of the base substrate; the second electrode around the second groove contacts the second surface of the base substrate so that a closed space is formed in the second groove.

[0047] In the pressure chip provided by the present invention, the material of the first conductive layer and the material of the third conductive layer are both metal;

[0048] The through hole includes a second through hole and a third through hole that are spaced apart; the connecting pad includes a first connecting pad and a second connecting pad; wherein the first connecting pad is located at a position corresponding to the second through hole, and the second connecting pad is located at a position corresponding to the third through hole; and the second through hole is located within the orthographic projection of the counter electrode on the substrate;

[0049] The second through hole and the third through hole are located in the pressure sensing area;

[0050] The first conductive layer also includes:

[0051] A fourth connection structure is located in the second through hole; the counter electrode is located on a side of the fourth connection structure away from the first surface; one end of the fourth connection structure is connected to the counter electrode, and the other end is connected to the first connection pad;

[0052] The first connection structure is located in the third through hole; one end of the first connection structure is electrically connected to the sensing electrode, and the other end of the first connection structure is electrically connected to the second connection pad.

[0053] In the pressure chip provided by the present invention, within the range covered by the orthographic projection of the sensing electrode on the substrate, the second surface is a plane;

[0054] The surface of the sensing electrode facing the base substrate has a second cavity; the second cavity is used to make the opposing electrode and the sensing electrode have a first set distance along the thickness direction of the base substrate; the orthographic projection of the second cavity on the base substrate coincides with the orthographic projection of the first cavity on the base substrate; the sensing electrodes around the second cavity are in contact with the second surface of the base substrate, so that a closed space is formed in the second cavity.

[0055] In the pressure chip provided by the present invention, the second surface of the substrate includes a first groove; the first groove is located within the positive projection of the sensing electrode on the substrate, and the positive projection of the bottom of the first cavity on the substrate is located in the area where the first groove is located; the opposing electrode is located in the first groove, and the second through hole is located in the first groove; the surface of the sensing electrode facing the substrate is a plane, and the first groove is used to make the opposing electrode and the sensing electrode separated by a first set distance along the thickness direction of the substrate; the sensing electrodes around the first groove are in contact with the second surface of the substrate to form a closed space in the first groove.

[0056] In the pressure chip provided by the present invention, the passive device structure includes an inductor structure;

[0057] The through hole includes a plurality of fourth through holes; the connecting pads also include a third connecting pad and a fourth connecting pad;

[0058] A plurality of fourth through holes are located in the passive device region;

[0059] The third conductive layer also includes:

[0060] A plurality of first inductor leads are located on a side of the second surface facing away from the first surface and located in a passive device area;

[0061] A plurality of second inductor leads are located on a side of the first surface facing away from the second surface and are located in a passive device area;

[0062] A plurality of second connection structures are located in the fourth through hole; the second connection structures are used to connect the first inductor lead wire and the second inductor lead wire end to end to form an inductor structure;

[0063] One end of the inductor structure is electrically connected to the third connection pad, and the other end of the inductor structure is electrically connected to the fourth connection pad.

[0064] In the pressure chip provided by the present invention, the passive device structure also includes a capacitor structure;

[0065] The through hole further includes a fifth through hole and a sixth through hole which are arranged at intervals; the connecting pad further includes a fifth connecting pad and a sixth connecting pad; wherein the fifth connecting pad is located at a position corresponding to the fifth through hole, and the sixth connecting pad is located at a position corresponding to the sixth through hole;

[0066] The fifth through hole and the sixth through hole are located in the passive device area;

[0067] The third conductive layer also includes:

[0068] a fifth connecting structure, located in the fifth through hole;

[0069] A first electrode is located on a side of the fifth connection structure away from the first surface; the orthographic projection of the first electrode on the substrate covers the fifth through hole; one end of the fifth connection structure is electrically connected to the first electrode, and the other end is connected to the fifth connection pad;

[0070] A third connecting structure is located in the sixth through hole;

[0071] The fourth conductive layer also includes: a second electrode, located in the passive device area; the orthographic projection of the second electrode on the substrate covers the first electrode; along the thickness direction of the substrate, the second electrode is separated from the first electrode by a second set distance to form a capacitor structure; one end of the third connection structure is electrically connected to the second electrode, and the other end is connected to the sixth connection pad.

[0072] In the pressure chip provided by the present invention, within the range of the orthographic projection of the second electrode on the substrate, the second surface is a plane;

[0073] The surface of the second electrode facing the substrate has a third cavity; the orthographic projection of the third cavity on the substrate covers the orthographic projection of the first electrode on the substrate; the third cavity is used to make the second electrode and the first electrode have a second set distance in the thickness direction of the substrate; the second electrodes around the third cavity are in contact with the second surface of the substrate, so that a closed space is formed in the third cavity; or,

[0074] The second surface of the base substrate also includes a second groove; the second groove is located within the positive projection of the second electrode on the base substrate; the fifth through hole and the first electrode are both located in the second groove; the surface of the second electrode facing the base substrate is a plane, and the second groove is used to make the second electrode and the first electrode have a second set distance along the thickness direction of the base substrate; the second electrode around the second groove is in contact with the second surface of the base substrate, so that a closed space is formed in the second groove.

[0075] In the pressure chip provided by the present invention, the second conductive layer further includes:

[0076] A first differential electrode is located in the pressure sensing area; the first differential electrode and the sensing electrode are arranged side by side and connected to each other;

[0077] The first conductive layer also includes:

[0078] A second differential electrode is located in the pressure sensing area; the second differential electrode and the counter electrode are spaced from each other; the orthographic projection of the second differential electrode on the substrate is located within the orthographic projection of the first differential electrode on the substrate; along the thickness direction of the substrate, the first differential electrode and the second differential electrode are separated by a third set distance; the sensing electrode, the counter electrode, the first differential electrode and the second differential electrode constitute a pressure sensing structure;

[0079] The first differential electrode has a fourth cavity on the side facing the glass cover; the orthographic projection of the second differential electrode on the base substrate is located within the orthographic projection of the fourth cavity on the base substrate; and the glass cover covers the fourth cavity to form a closed space.

[0080] According to a second aspect of an embodiment of the present invention, there is provided a pressure sensor, comprising a signal processing circuit and any one of the pressure chips mentioned above, wherein the pressure chip is electrically connected to the signal processing circuit.

[0081] The beneficial effects of the present invention are as follows:

[0082] The present invention provides a pressure chip and a pressure sensor, the pressure chip comprising: a substrate, a first conductive layer, a second conductive layer, a third conductive layer and a fourth conductive layer. The substrate comprises a first surface and a second surface opposite to each other in the thickness direction, and a plurality of through holes extending from the first surface to the second surface. The first conductive layer and the third conductive layer are located in the same film layer, and at least in the through holes, and the second conductive layer and the fourth conductive layer are located on the side of the second surface away from the first surface. The first surface comprises a non-overlapping pressure sensing area and a passive device area. In the pressure sensing area, the first conductive layer and the second conductive layer form a pressure sensing structure; in the passive device area, the third conductive layer and the fourth conductive layer form a passive device structure. The pressure chip provided in an embodiment of the present invention integrates at least one passive device structure (capacitor, inductor, resistor, etc.) in the pressure chip, and then forms a complete signal processing circuit by electrically connecting the passive device integrated in the pressure chip to the signal processing circuit. Compared with the prior art, the structure of the signal processing circuit can be greatly simplified and the design difficulty can be reduced. With the pressure chip after the integrated passive device structure, the pressure sensing structure and the passive device structure can be bonded with the signal processing circuit and packaged at the same time, which is conducive to reducing the packaging difficulty and reducing the volume of the packaged pressure sensor, thereby realizing further miniaturization of the pressure sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings introduced below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0084] Figure 1 One of the cross-sectional structural schematic diagrams of the pressure chip provided by an embodiment of the present invention;

[0085] Figure 2 The second schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0086] Figure 3 The third schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0087] Figure 4 A fourth schematic diagram of the cross-sectional structure of a pressure chip provided by an embodiment of the present invention;

[0088] Figure 5 A fifth schematic diagram of the cross-sectional structure of a pressure chip provided in an embodiment of the present invention;

[0089] Figure 6 This is a schematic diagram of a top view of a pressure chip provided by an embodiment of the present invention;

[0090] Figure 7 This is one of the bottom-up structural schematic diagrams of the pressure chip provided by an embodiment of the present invention;

[0091] Figure 8 A sixth schematic diagram of the cross-sectional structure of a pressure chip provided by an embodiment of the present invention;

[0092] Fig. 9 The seventh schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0093] Fig.10 The eighth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0094] Fig.11 A ninth schematic diagram of the cross-sectional structure of a pressure chip provided by an embodiment of the present invention;

[0095] Fig.12 The second schematic diagram of the top view structure of the pressure chip provided by the embodiment of the present invention;

[0096] Fig.13 The second bottom view structural schematic diagram of the pressure chip provided by the embodiment of the present invention;

[0097] Fig.14 The tenth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0098] Fig.15 The eleventh schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0099] Fig.16 The twelfth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0100] Fig.17 The thirteenth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0101] Fig.18 A fourteenth schematic diagram of the cross-sectional structure of a pressure chip provided in an embodiment of the present invention;

[0102] Fig.19 The fifteenth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention;

[0103] Fig. 20 A sixteenth schematic diagram of the cross-sectional structure of a pressure chip provided in an embodiment of the present invention;

[0104] Figure 21a to Figure 21d A schematic diagram of the manufacturing process of a pressure chip using a glass reflow solution provided in an embodiment of the present invention;

[0105] Figure 22a to Figure 22cA schematic diagram of the manufacturing process of a pressure chip using a glass perforation solution provided in an embodiment of the present invention;

[0106] Fig.23 A schematic diagram of the cross-sectional structure of a pressure sensor provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0107] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the present invention will be further described below with reference to the accompanying drawings and examples. However, the exemplary embodiments can be implemented in various forms and should not be understood as being limited to the embodiments described herein; on the contrary, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concepts of the exemplary embodiments to those skilled in the art. The same figure marks in the figures represent the same or similar structures, and thus their repeated descriptions will be omitted. The words expressing position and direction described in the present invention are all explained using the accompanying drawings as examples, but changes can be made as needed, and the changes made are all included in the scope of protection of the present invention. The drawings of the present invention are only used to illustrate the relative position relationship and do not represent the true proportions.

[0108] With the continuous development of Internet of Things technology, the demand for the use of microelectromechanical systems (MEMS) sensors, which are key sensing components in the Internet of Things, is increasing. Among them, MEMS pressure sensors are mainly used to measure atmospheric pressure. When used in smart devices such as mobile phones, the altitude can be calculated by the air pressure at different heights, and accurate three-dimensional positioning can be performed in conjunction with satellite navigation systems. MEMS pressure sensors include a pressure chip and an application-specific integrated circuit (ASIC) chip. The pressure chip is connected by leads and encapsulated on the surface of the ASIC chip. The pressure chip is used to generate capacitance / resistance changes when subjected to pressure, and the ASIC chip is used to convert the pressure signal into an electrical signal according to the change in capacitance / resistance, which is used to measure the pressure. A large number of passive devices (capacitors, inductors, etc.) are dispersed on the ASIC chip to form a signal processing circuit for converting the pressure signal into an electrical signal. The dispersed passive devices need to be packaged separately, resulting in a large overall size of the sensor, which is difficult to further miniaturize.

[0109] In view of this, the present application provides a pressure chip and a pressure sensor to solve the above problems.

[0110] Figure 1 This is one of the schematic cross-sectional structural diagrams of the pressure chip provided in an embodiment of the present invention.

[0111] In a first aspect of an embodiment of the present invention, a pressure chip is provided. Figure 1 As shown, the pressure chip 1 includes: a base substrate 100 , a first conductive layer 10 , a second conductive layer 20 , a third conductive layer 60 and a fourth conductive layer 70 .

[0112] The substrate 100 includes a first surface 101 and a second surface 102 that are opposite to each other in the thickness direction, and a plurality of through holes K extending from the first surface 101 to the second surface 102. In a specific implementation, the substrate 100 can be set as a flat structure, wherein the first surface 101 is parallel to the second surface 102 to simplify the manufacturing process, which is not limited here. The first conductive layer 10 and the third conductive layer 60 are located in the same film layer, and the first conductive layer 10 and the third conductive layer 60 are at least located in the through hole K. The second conductive layer 20 and the fourth conductive layer 70 are located in the same film layer, and the second conductive layer 20 and the fourth conductive layer 70 are located on the side of the second surface 102 away from the first surface 101. In an embodiment of the present invention, the first conductive layer 10 and the third conductive layer 60 are located in the same film layer, and the second conductive layer 20 and the fourth conductive layer 70 are located in the same film layer, which specifically means that the first conductive layer 10 and the third conductive layer 60 can be made of the same material and in the same process, and the second conductive layer 20 and the fourth conductive layer 70 can be made of the same material and in the same process, which is not limited here. Among them, the first surface 101 includes a non-overlapping pressure sensing area S1 and a passive device area S2. In the pressure sensing area S1, the first conductive layer 10 and the second conductive layer 20 form a pressure sensing structure 200; in the passive device area S2, the third conductive layer 60 and the fourth conductive layer 70 form a passive device structure 300.

[0113] The pressure sensing structure 200 is used to generate capacitance / resistance changes when subjected to external pressure, and transmit the capacitance / resistance changes to the signal processing circuit of the pressure sensor. The signal processing circuit converts the pressure signal into an electrical signal according to the capacitance / resistance changes, which is used to measure the pressure. In specific implementation, the signal processing circuit can be an ASIC chip, a Field Programmable Gate Array (FPGA), a printed circuit board (PCB) with computing functions, and other chips or circuit boards, which are not limited here. In an embodiment of the present invention, a first conductive layer 10 and a second conductive layer 20, as well as a third conductive layer 60 and a fourth conductive layer 70, which are arranged opposite to each other, can be formed on a substrate, and a pressure sensing structure 200 and a passive device structure 300 can be simultaneously manufactured, so that at least one passive device structure 300 (capacitor, inductor, resistor, etc.) in the signal processing circuit in the prior art can be integrated into the pressure chip 200, and then the passive device 300 integrated in the pressure chip 200 can be electrically connected to the signal processing circuit to form a complete signal processing circuit. Compared with the prior art, the structure of the signal processing circuit can be greatly simplified and the design difficulty can be reduced. With a pressure chip with an integrated passive device structure, the pressure sensing structure 200 and the passive device structure 300 can be bonded to the signal processing circuit and packaged at the same time, which is conducive to reducing the packaging difficulty and reducing the volume of the packaged pressure sensor, and further realizing the integration and miniaturization of the pressure sensor.

[0114] In some embodiments, the material of the substrate 100 can be glass material, such as borosilicate glass. In the prior art, when a silicon wafer is used as a substrate, due to the large noise and loss generated by the semiconductor material as the substrate, a more complex signal processing circuit needs to be designed to reduce the noise and loss. In the embodiment of the present invention, the substrate is made of a glass material with high resistance and low dielectric loss, which can reduce the noise and loss in the device structure, thereby further simplifying the signal processing circuit and reducing the size of the pressure sensor. In some embodiments, the substrate 100 can also be made of other materials with high resistance and low dielectric loss characteristics, which are not limited here. In specific implementation, according to actual needs, the shape of the substrate 100 can be rectangular, square or circular, etc., which is not limited here.

[0115] In some embodiments, the material of the second conductive layer 20 and the material of the fourth conductive layer 70 can both be doped bulk silicon (Bulk Silicon), and the second conductive layer 20 and the fourth conductive layer 70 can be simultaneously manufactured by etching the bulk silicon. Bulk silicon is usually a block of silicon with a certain three-dimensional size, and the second conductive layer 20 and the fourth conductive layer 70 can be directly etched to form the shape of the pressure sensing structure 200 and the passive device structure 300, and then the second conductive layer 20 and the fourth conductive layer 70 are bonded to the substrate 100 by anodic bonding to improve the connection strength and sealing performance. In addition, the silicon material and the glass material have similar thermal expansion coefficients. After the second conductive layer 20 and the fourth conductive layer 70 made of bulk silicon are bonded to the substrate 100 made of glass, the risk of peeling between the second conductive layer 20 and the fourth conductive layer 70 and the substrate 100 due to the large difference in expansion rate under extreme temperature conditions can be reduced.

[0116] In some embodiments, Figure 1 As shown, the pressure chip also includes: a glass cover plate 500. The glass cover plate 500 is located on the side of the second conductive layer 20 and the fourth conductive layer 70 away from the base substrate 100. The orthographic projection of the glass cover plate 500 on the base substrate 100 covers the orthographic projection of the pressure sensing structure 200 on the base substrate 100 and the orthographic projection of the passive device structure 300 on the base substrate 100. In an embodiment of the present invention, the pressure chip is packaged by the glass cover plate 500 to protect the pressure sensing structure 200 and the passive device structure 300. Compared with using silicon as a packaging material, the noise and loss in the device structure can be reduced, thereby further simplifying the signal processing circuit and reducing the size of the pressure sensor. In a specific implementation, the glass cover plate 500 can also be connected to the second conductive layer 20 and the fourth conductive layer 70 by anodic bonding to improve the connection strength and sealing performance. In addition, the silicon material and the glass material have similar thermal expansion coefficients, which can reduce the risk of peeling between the second conductive layer 20, the fourth conductive layer 70 and the glass cover plate 500 due to the large difference in expansion rate under extreme temperature conditions. The size of the glass cover plate 500 is the same as that of the base substrate 100, or slightly larger than that of the base substrate 100 to ensure that the pressure sensing structure 200 and the passive device structure 300 are fully covered, which is not limited here.

[0117] In some embodiments, Figure 1 As shown, the pressure chip further includes: a connection pad 40. The connection pad 40 is located on the side of the first surface 101 away from the second surface 102. The pressure sensing structure 200 and the passive device structure 300 are electrically connected to the connection pad 40. The connection pad 40 is used to connect to the signal processing circuit to form a pressure sensor. Figure 1As shown, the connection pad 40 is located on the surface of the pressure chip, and the pressure sensing structure 200 and the passive device structure 300 are electrically connected to the connection pad through through holes penetrating the substrate 100 .

[0118] In some embodiments, Figure 1 As shown, in the pressure sensing area S1, the first conductive layer 10 includes an opposing electrode 202, and the second conductive layer 20 includes a sensing electrode 201. The orthographic projection of the opposing electrode 202 on the base substrate 100 is located within the orthographic projection of the sensing electrode 201 on the base substrate. Along the thickness direction of the base substrate 100, the opposing electrode 202 and the sensing electrode 201 are separated by a first set distance h1 to form a pressure sensing structure 200. The pressure chip provided in the embodiment of the present invention can adopt a capacitive pressure sensing structure, wherein the first set distance h1 between the opposing electrode 202 and the sensing electrode 201 can be set according to actual needs and is not limited here.

[0119] like Figure 1 As shown, the surface of the sensing electrode 201 facing away from the substrate 100 has a first cavity D1. In specific implementation, after the second conductive layer 20 is bonded to the substrate 100 through an anodic bonding process, the bulk silicon used to form the second conductive layer 20 is etched to form the first cavity D1. The orthographic projection of the counter electrode 202 on the substrate 200 is located within the orthographic projection of the bottom of the first cavity D1 on the substrate 100. The thickness of the sensing electrode 201 in the corresponding area of ​​the bottom of the first cavity D1 is less than the thickness of the sensing electrode 201 around the bottom of the first cavity D1; wherein, in the corresponding area of ​​the bottom of the first cavity D1, the sensing electrode 201 has a smaller thickness, thereby forming a pressure-sensitive film structure, which is thinner and more sensitive to pressure changes, and can sense external air pressure changes in a timely manner. The orthographic projection of the opposing electrode 202 on the base substrate 100 is located within the orthographic projection of the bottom of the first cavity D1 on the base substrate 100, so that the size of the pressure-sensitive membrane structure is slightly larger than the size of the opposing electrode 202, so as to fully utilize the surface of the opposing electrode 202 to form a larger capacitance value and expand the pressure sensing range.

[0120] like Figure 1 As shown, the glass cover plate 500 includes a first through hole K1 that penetrates the glass cover plate 500 along the thickness direction. The orthographic projection of the first through hole K1 on the base substrate 100 is located within the orthographic projection of the first cavity D1 on the base substrate 100, so that the first cavity D1 is connected to the external environment through the first through hole K1, so that the pressure-sensitive film structure formed by the sensing electrode 201 can sense the external air pressure and realize the pressure sensing function.

[0121] Figure 2 The second schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention; Figure 3The third schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention; Figure 4 A fourth schematic diagram of the cross-sectional structure of a pressure chip provided in an embodiment of the present invention; Figure 5 The fifth schematic diagram of the cross-sectional structure of the pressure chip provided in the embodiment of the present invention.

[0122] In some embodiments, the material of the first conductive layer 10 and the material of the third conductive layer 60 are both doped bulk silicon, and the first conductive layer 10 and the third conductive layer 60 can be simultaneously manufactured by etching bulk silicon. Figure 2 to Figure 5 As shown, the through hole K in the base substrate 100 includes a second through hole K2 and a third through hole K3 arranged at intervals. The connecting pad 40 includes a first connecting pad 401 and a second connecting pad 402. The first connecting pad 401 is located at a position corresponding to the second through hole K2, and the second connecting pad 402 is located at a position corresponding to the third through hole K3. The second through hole K2 and the third through hole K3 are located in the pressure sensing area S1, and the counter electrode 202 is filled in the second through hole K2 and is electrically connected to the first connecting pad 401.

[0123] The first conductive layer 10 further includes: a first connection structure 601. The first connection structure 601 is located in the third through hole K3. The orthographic projection of the sensing electrode 201 on the base substrate 100 covers the third through hole K3, so that one end of the first connection structure 601 is electrically connected to the sensing electrode 301, and the other end is electrically connected to the second connection pad 402. In this embodiment, the material of the first conductive layer 10 is doped bulk silicon. When manufacturing the counter electrode 202 and the first connection structure 601, the bulk silicon used to form the first conductive layer 10 can be etched first to form the shape of the counter electrode 202 and the first connection structure 601, and then the base substrate 100 surrounding the counter electrode 202 and the first connection structure 601 is formed by a glass reflow process, which is not limited here.

[0124] In some embodiments, Figure 2 and Figure 3As shown, within the range covered by the orthographic projection of the sensing electrode 201 on the base substrate 100, the second surface 102 is a plane. The surface of the sensing electrode 201 facing the base substrate 100 has a second cavity D2. The second cavity D2 can be formed by etching the bulk silicon used to form the second conductive layer 20 before the second conductive layer 20 is anodically bonded to the base substrate. The second cavity D2 is used to make the opposing electrode 202 and the sensing electrode 201 be separated by a first set distance h1 along the thickness direction of the base substrate 100. The orthographic projection of the second cavity D2 on the base substrate 100 coincides with the orthographic projection of the first cavity D1 on the base substrate 100. The sensing electrode 201 around the second cavity D2 is in contact with the second surface 102 of the base substrate 100. Specifically, the sensing electrode 201 around the second cavity D2 and the base substrate 100 can be sealed by anodizing or the like to form a closed space in the second cavity D2. In a specific implementation, the first cavity D1 and the second cavity D2 have the same shape, so that the thickness of the pressure-sensitive film structure formed at the bottom of the first cavity D1 is smaller than the thickness of other areas of the sensing electrode, so as to improve sensitivity. A closed space is formed in the second cavity D2, so that the sensing electrode 201 senses the change of external air pressure only through the first cavity D1 and the first through hole K1. When the external air pressure changes, the pressure-sensitive film structure bends and deforms, resulting in a change in capacitance, and outputs, thereby reducing interference factors and improving accuracy.

[0125] In some embodiments, Figure 4 and Figure 5As shown, the second surface 102 of the base substrate 100 includes a first groove G1. The first groove G1 is located within the orthographic projection of the sensing electrode 201 on the base substrate 100 to ensure that the sensing electrode 201 can be normally overlapped on the base substrate 100. The orthographic projection of the bottom of the first cavity D1 on the base substrate 100 is located in the area where the first groove G1 is located, so that the pressure-sensitive film structure formed at the bottom of the first cavity D1 can be fully utilized to form a larger capacitor with the counter electrode 202. The second through hole K2 is located in the first groove G1. The surface of the sensing electrode 201 facing the base substrate 100 is a plane, and the sensing electrode 201 only needs to make the first cavity D1 to form a pressure-sensitive film structure, which greatly simplifies the process. In specific implementation, the depth of the first cavity D1 can be appropriately increased to reduce the thickness of the pressure-sensitive film structure and improve the sensitivity, which is not limited here. Among them, the first groove G1 is used to make the counter electrode 202 and the sensing electrode 201 separated by a first set distance h1 along the thickness direction of the base substrate 100. The sensing electrode 201 around the first groove G1 is in contact with the second surface 102 of the base substrate 100. Specifically, the sensing electrode 201 around the first groove G1 and the base substrate 100 can be sealed by anodic bonding or other methods to form a closed space in the first groove G1. A closed space is formed in the first groove G1, so that the sensing electrode 201 senses the change of external air pressure only through the first cavity D1 and the first through hole K1. When the external air pressure changes, the pressure-sensitive film structure bends and deforms, resulting in a change in capacitance, and output is performed, thereby reducing interference factors and improving accuracy.

[0126] Figure 6 One of the schematic diagrams of the top view structure of the pressure chip provided by the embodiment of the present invention; Figure 7 This is one of the bottom-up structural schematic diagrams of the pressure chip provided in an embodiment of the present invention.

[0127] In some embodiments, Figure 2 , Figure 4 and Figure 6 , Figure 7 As shown, the passive device structure 300 includes an inductor structure 301 .

[0128] The through holes K in the base substrate 100 include a plurality of fourth through holes K4 , and the plurality of fourth through holes K4 are located in the passive device region S2 . The connecting pads 40 also include a third connecting pad 403 and a fourth connecting pad 404 .

[0129] The third conductive layer 60 includes: a plurality of second connection structures 602. The plurality of second connection structures 602 are located in the fourth through hole K4. The fourth conductive layer 70 includes: a plurality of first inductor leads 3012. The plurality of first inductor leads 3012 are located on the side of the second surface 102 away from the first surface 101, and are located in the passive device area S2. The orthographic projection of the fourth through hole K4 on the substrate substrate 100 is located within the orthographic projection of the first inductor lead 3012 on the substrate substrate 100. The pressure chip also includes: a fifth conductive layer 30. The fifth conductive layer 30 is located on the side of the first surface 101 away from the second surface 102. The fifth conductive layer 30 includes a plurality of second inductor leads 3011, and the second inductor leads 3011 are located in the passive device area S2. In a specific implementation, the material of the fifth conductive layer 30 may be metal, and the material of the fifth conductive layer 30 may be formed as a whole layer on the side of the first surface 101 of the substrate away from the second surface 102 by thin film deposition or the like, and then a plurality of mutually spaced second inductor leads 3011 may be formed by etching or the like. In the process of etching the fifth conductive layer 30, a portion of the fifth conductive layer 30 between the connection pad 40 and the first conductive layer 10 may be retained to form a bonding layer, thereby improving the connection strength between the connection pad 40 and the first conductive layer 10 and reducing the contact resistance.

[0130] The second connection structure 602 is used to connect the first inductor lead 3012 and the second inductor lead 3011 end to end, and is wound around the substrate 100 to form the inductor structure 301. One end of the inductor structure is electrically connected to the third connection pad 403, and the other end is electrically connected to the fourth connection pad 404, so as to be connected to the signal processing circuit through the third connection pad 403 and the fourth connection pad 404.

[0131] In some embodiments, Figure 3 and Figure 5 As shown, the passive device structure 300 further includes a capacitor structure 302 .

[0132] The through hole K in the base substrate 100 further includes a fifth through hole K5 and a sixth through hole K6 which are arranged at intervals. The connecting pad 40 further includes a fifth connecting pad 405 and a sixth connecting pad 406. The fifth connecting pad 405 is located at a position corresponding to the fifth through hole K5, and the sixth connecting pad 406 is located at a position corresponding to the sixth through hole K6. The fifth through hole K5 and the sixth through hole K6 are both located in the passive device area S2.

[0133] The third conductive layer 60 includes: a first electrode 3021 and a third connection structure 603. The first electrode 3021 is located in the fifth through hole K5 and is electrically connected to the fifth connection pad 405. The third connection structure 603 is located in the sixth through hole K6. The fourth conductive layer 70 includes: a second electrode 3022. The second electrode 3022 is located in the passive device area S2. The orthographic projection of the second electrode 3022 on the substrate 100 covers the first electrode 3021. Along the thickness direction of the substrate 100, the second electrode 3022 is separated from the first electrode 3021 by a second set distance h2 to form a capacitor structure 302. In a specific implementation, the second set distance h2 between the second electrode 3022 and the first electrode 3021 can be set according to demand, and is not limited here. One end of the third connection structure 603 is electrically connected to the second electrode 3022, and the other end is connected to the sixth connection pad 406. The fifth connection pad 405 and the sixth connection pad 406 are used to make electrical connections between the capacitor structure 302 and the signal processing circuit.

[0134] In some embodiments, Figure 3 As shown, within the range covered by the orthographic projection of the second electrode 3022 on the substrate 100, the second surface 102 is a plane. The surface of the second electrode 3022 facing the substrate 100 has a third cavity D3. The third cavity D3 is used to make the second electrode 3022 and the first electrode 3021 separated by a second set distance h2 along the thickness direction of the substrate 100. The orthographic projection of the third cavity D3 on the substrate 100 covers the fifth through hole K5, so that the first electrode 3021 is located within the orthographic projection of the third cavity D3 on the substrate 100. The second electrode 3022 around the third cavity D3 contacts the second surface 102 of the substrate 100. Specifically, the second electrode 3022 around the third cavity D3 and the second surface 102 of the substrate 100 can be sealed by anode bonding or the like, so that a closed space is formed in the third cavity D3. Furthermore, the side of the second electrode 3022 facing away from the base substrate 100 is sealed with the glass cover plate 500 by means of anodic bonding, so as to prevent the capacitor structure 302 from being affected by changes in the external environment.

[0135] In some embodiments, Figure 5As shown, the second surface 102 of the base substrate 100 further includes a second groove G2. The second groove G2 is located within the orthographic projection of the second electrode 3022 on the base substrate 100. The fifth through hole K5 is located in the second groove G2, so that the first electrode 3021 is located within the orthographic projection of the second electrode 3022 on the base substrate 100. The surface of the second electrode 3022 facing the base substrate 100 is a plane, which can simplify the manufacturing process of the second electrode 3022 and improve the strength of the second electrode 3022. The second groove G2 is used to make the second electrode 3022 and the first electrode 3021 be separated by a second set distance h2 along the thickness direction of the base substrate 100. The second electrode 3022 around the second groove G2 contacts the second surface 102 of the base substrate 100, and specifically, the second electrode 3022 around the second groove G2 is sealed with the second surface 102 of the base substrate 100 by anodic bonding, so that a closed space is formed in the second groove G2. Furthermore, the side of the second electrode 3022 facing away from the base substrate 100 and the glass cover plate 500 can be sealed by anode bonding or other methods to prevent the capacitor structure 302 from being affected by changes in the external environment.

[0136] Figure 8 A sixth schematic diagram of the cross-sectional structure of a pressure chip provided by an embodiment of the present invention; Fig. 9 The seventh schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention; Fig.10 The eighth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention; Fig.11 The ninth schematic diagram of the cross-sectional structure of the pressure chip provided in an embodiment of the present invention.

[0137] In some embodiments, the material of the first conductive layer 10 and the material of the third conductive layer 60 are both metals, and the first conductive layer 10 and the third conductive layer 60 can be simultaneously manufactured by thin film deposition or the like. Figure 8 to Figure 11 As shown, the through hole K in the base substrate 100 includes a second through hole K2 and a third through hole K3 arranged at intervals. The connecting pad 40 includes a first connecting pad 401 and a second connecting pad 402. The first connecting pad 401 is located at a position corresponding to the second through hole K2, and the second connecting pad 402 is located at a position corresponding to the third through hole K3. The second through hole K2 and the third through hole K3 are both located in the pressure sensing area S2, and the second through hole K2 is located within the orthographic projection of the counter electrode 202 on the base substrate 100.

[0138] The first conductive layer 10 further includes: a fourth connection structure 604 and a first connection structure 601. The fourth connection structure 604 is located in the second through hole K2. The counter electrode 202 is located on the side of the fourth connection structure 604 away from the first surface 101. One end of the fourth connection structure 604 is connected to the counter electrode 202, and the other end is connected to the first connection pad 601. The first connection structure 601 is located in the third through hole K3. One end of the first connection structure 601 is electrically connected to the sensing electrode 201, and the other end is electrically connected to the second connection pad 602. The first connection pad 401 and the second connection pad 402 are used for electrical connection between the pressure sensing structure 200 and the signal processing circuit.

[0139] exist Figure 8 to Figure 11 In the illustrated embodiment, when manufacturing the counter electrode 202, the first connection structure 601 and the fourth connection structure 604, the base substrate 100 of the glass material can be opened by laser modification-wet etching, high-voltage discharge, etc. to manufacture the second through hole K2 and the third through hole K3, and then the metal material is filled in the second through hole K2, the third through hole K3 and the surface of the base substrate 100 by physical vapor deposition, etc., and finally the metal material is etched to form the counter electrode 202, the first connection structure 601 and the fourth connection structure 604, which is beneficial to improve the opening efficiency and the opening density, so that more pressure sensing structures 200 and / or passive device structures 300 can be integrated on the pressure chip of the same size.

[0140] In some embodiments, Figure 8 and Fig. 9 As shown, within the range covered by the orthographic projection of the sensing electrode 201 on the base substrate 100, the second surface 102 is a plane. The surface of the sensing electrode 201 facing the base substrate 100 has a second cavity D2. The second cavity D2 is used to make the opposing electrode 202 and the sensing electrode 201 separated by a first set distance h1 along the thickness direction of the base substrate 100. The orthographic projection of the second cavity D2 on the base substrate 100 coincides with the orthographic projection of the first cavity D1 on the base substrate 100. The sensing electrode 201 around the second cavity D2 contacts the second surface 102 of the base substrate 100. Specifically, the sensing electrode 201 around the second cavity D2 is sealed with the base substrate 100 by anodic bonding or the like, so that a closed space is formed in the second cavity D2. In a specific implementation, the first cavity D1 and the second cavity D2 have the same shape, so that the thickness of the pressure-sensitive film structure formed at the bottom of the first cavity D1 is less than the thickness of other areas of the sensing electrode, so as to improve the sensitivity. A closed space is formed in the second cavity D2, so that the sensing electrode 201 senses changes in external air pressure only through the first cavity D1 and the first through hole K1. When the external air pressure changes, the pressure-sensing film structure bends and deforms, causing the capacitance to change and output, thereby reducing interference factors and improving accuracy.

[0141] In some embodiments, Fig.10 and Fig.11 As shown, the second surface 102 of the base substrate 100 includes a first groove G1. The first groove G1 is located within the orthographic projection of the sensing electrode 201 on the base substrate 100, and the orthographic projection of the bottom of the first cavity D1 on the base substrate 100 is located in the area where the first groove G1 is located, so that the pressure-sensitive film structure formed at the bottom of the first cavity D1 can be fully utilized to form a larger capacitance with the opposing electrode 202. The opposing electrode 202 is located in the first groove G1, and the second through hole K2 is located in the first groove G1. The surface of the sensing electrode 201 facing the base substrate 100 is a plane, and the sensing electrode 201 only needs to make the first cavity D1 to form a pressure-sensitive film structure, which greatly simplifies the process. In specific implementation, the depth of the first cavity D1 can be appropriately increased, thereby reducing the thickness of the pressure-sensitive film structure and improving the sensitivity, which is not limited here. The first groove G1 is used to make the opposing electrode 202 and the sensing electrode 201 separated by a first set distance h1 along the thickness direction of the base substrate 100. The sensing electrode 201 around the first groove G1 is in contact with the second surface 102 of the base substrate 100. Specifically, the sensing electrode 201 around the first groove G1 and the base substrate 100 can be sealed by anodic bonding or other methods to form a closed space in the first groove G1. A closed space is formed in the first groove G1, so that the sensing electrode 201 senses the change of external air pressure only through the first cavity D1 and the first through hole K1. When the external air pressure changes, the pressure-sensitive film structure bends and deforms, resulting in a change in capacitance, and output is performed, thereby reducing interference factors and improving accuracy.

[0142] Fig.12 The second schematic diagram of the top view structure of the pressure chip provided by the embodiment of the present invention; Fig.13 The second schematic diagram of the bottom view structure of the pressure chip provided in the embodiment of the present invention.

[0143] In some embodiments, Figure 8 , Fig.10 , Fig.12 and Fig.13 As shown, the passive device structure 300 includes an inductor structure 301 .

[0144] The through holes K in the base substrate 100 include a plurality of fourth through holes K4. The connection pads 40 also include a third connection pad 403 and a fourth connection pad 404. The plurality of fourth through holes K4 are located in the passive device region S2.

[0145] The third conductive layer 60 includes: a plurality of first inductor leads 3012, a plurality of second inductor leads 3011 and a plurality of second connection structures 602. The plurality of first inductor leads 3012 are located on the side of the first surface 101 away from the second surface 102, and are located in the passive device area S2. The plurality of second inductor leads 3011 are located on the side of the first surface 101 away from the second surface 102, and are located in the passive device area S2. The plurality of second connection structures 602 are located in the fourth through hole K4. The second connection structure 602 is used to connect the first inductor leads 3012 and the second inductor leads 3011 end to end, and to be wound around the substrate 100 to form the inductor structure 301. The plurality of first inductor leads 3012 and the plurality of second inductor leads 3011 can be formed by etching the third conductive layer 60 deposited on the surface of the substrate 100, so that there is no need to set a fourth conductive layer, which is not limited here. One end of the inductor structure 301 is electrically connected to the third connection pad 403 , and the other end is electrically connected to the fourth connection pad 404 , so as to be connected to the signal processing circuit through the third connection pad 403 and the fourth connection pad 404 .

[0146] In some embodiments, Fig. 9 and Fig.11 As shown, the passive device 300 further includes a capacitor structure 302 .

[0147] The through hole K of the base substrate 100 further includes a fifth through hole K5 and a sixth through hole K6 which are arranged at intervals. The connecting pad 40 further includes a fifth connecting pad 405 and a sixth connecting pad 405. The fifth connecting pad 405 is located at a position corresponding to the fifth through hole K5, and the sixth connecting pad 406 is located at a position corresponding to the sixth through hole K6. The fifth through hole K5 and the sixth through hole K6 are located in the passive device area S2.

[0148] The third conductive layer 60 includes: a fifth connection structure 605, a first electrode 3021 and a third connection structure 603. The fifth connection structure 605 is located in the fifth through hole K5. The first electrode 3021 is located on the side of the fifth connection structure 605 away from the first surface 101 of the substrate 100. The orthographic projection of the first electrode on the substrate 100 covers the fifth through hole K5. One end of the fifth connection structure 605 is electrically connected to the first electrode 3021, and the other end is connected to the fifth connection pad 405. The third connection structure 603 is located in the sixth through hole K6.

[0149] The fourth conductive layer 70 includes: a second electrode 3022. The second electrode 3022 is located in the passive device area S2. The orthographic projection of the second electrode 3022 on the base substrate 100 covers the first electrode 3021. Along the thickness direction of the base substrate 100, the second electrode 3022 is separated from the first electrode 3021 by a second set distance h2 to form a capacitor structure 302. In specific implementation, the second set distance h2 between the second electrode 3022 and the first electrode 3021 can be set according to demand, and is not limited here. One end of the third connection structure 603 is electrically connected to the second electrode 3022, and the other end is connected to the sixth connection pad 406. The fifth connection pad 405 and the sixth connection pad 406 are used for electrical connection between the capacitor structure 302 and the signal driving circuit.

[0150] In some embodiments, Fig. 9 As shown, within the range of the orthographic projection of the second electrode 3022 on the substrate 100, the second surface 102 is a plane. The surface of the second electrode 3022 facing the substrate 100 has a third cavity D3. The orthographic projection of the third cavity D3 on the substrate 100 covers the orthographic projection of the first electrode 3021 on the substrate. The third cavity D3 is used to make the second electrode 3022 and the first electrode 3021 separated by a second set distance h2 along the thickness direction of the substrate 100. The second electrode 3022 around the third cavity D3 is in contact with the second surface 102 of the substrate 100. Specifically, the second electrode 3022 around the third cavity D3 and the second surface 102 of the substrate 100 can be sealed by anodic bonding or the like, so that a closed space is formed in the third cavity D3. In addition, the side of the second electrode 3022 facing away from the substrate 100 is sealed with the glass cover plate 500 by anodic bonding to prevent the external environment changes from affecting the capacitor structure 302.

[0151] In some embodiments, Fig.11As shown, the second surface 102 of the base substrate 100 further includes a second groove G2. The second groove G2 is located within the orthographic projection of the second electrode 3022 on the base substrate 100. The fifth through hole K5 and the first electrode 3021 are both located in the second groove G2. The surface of the second electrode 3022 facing the base substrate 100 is a plane, which can simplify the manufacturing process of the second electrode 3022 and improve the strength of the second electrode 3022. The second groove G2 is used to make the second electrode 3022 and the first electrode 3021 be separated by a second set distance h2 along the thickness direction of the base substrate 100. The second electrode 3022 around the second groove G2 contacts the second surface 102 of the base substrate 100, and specifically, the second electrode 3022 around the second groove G2 is sealed with the second surface 102 of the base substrate 100 by anodic bonding, so that a closed space is formed in the second groove G2. Furthermore, the side of the second electrode 3022 facing away from the base substrate 100 and the glass cover plate 500 can be sealed by anode bonding or other methods to prevent the capacitor structure 302 from being affected by changes in the external environment.

[0152] Fig.14 The tenth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention; Fig.15 The eleventh schematic diagram of the cross-sectional structure of the pressure chip provided in an embodiment of the present invention.

[0153] exist Figure 2 to Figure 13 In the embodiment shown, the structure of the pressure chip is described by taking the pressure chip including only one pressure sensing structure 200 and one inductance structure 301, or the pressure chip including only one pressure sensing structure 200 and one capacitance structure 302 as an example. Fig.14 The pressure chip may include a pressure sensing structure 200, an inductance structure 301 and a capacitance structure 302 at the same time, and according to actual needs, the number of any one of the pressure sensing structure 200, the inductance structure 301 and the capacitance structure 302 may be one or more, which is not limited here.

[0154] In some embodiments, Figure 2 , Figure 4 , Figure 8 and Fig.10As shown, the passive device structure 300 in the pressure chip only includes the inductor structure 301. Since the height of the first inductor lead 3012 is usually lower than the height of the sensing electrode 201 when the inductor structure 301 is manufactured, when the glass cover plate 500 and the second conductive layer 20 are connected by anodic bonding, the first inductor lead 3012 cannot contact the glass cover plate 500 and seal the passive device area S2 of the pressure chip. On the side of the inductor structure 301 away from the pressure sensing structure 200, and on both sides adjacent to the side, a gap is formed between the substrate 100 and the glass cover plate, thereby connecting with the external environment. In specific implementation, as Figure 2 , Figure 4 , Figure 8 and Fig.10 As shown, on each side of the passive device area S2 that is not bonded to the glass cover plate 500 through the second conductive layer 20 for packaging, a sealant 700 can be filled between the base substrate 100 and the glass cover plate to seal the passive device area S2 to form a closed space to protect the inductor structure 301. The inside of the closed space mentioned in the embodiment of the present invention can be specifically filled with a vacuum or an inert gas, such as nitrogen, etc., which is not limited here. In some embodiments, the gap formed between the base substrate 100 and the glass cover plate may not be sealed, which is not limited here.

[0155] In some embodiments, Fig.14 and Fig.15 As shown, the pressure chip integrates a pressure sensing structure 200, an inductance structure 301 and a capacitance structure 302. During the specific manufacturing process, the height of the sensing electrode 201 of the pressure sensing structure 200 and the height of the second electrode 3022 of the capacitance structure 302 are greater than the height of the second inductance lead 302 of the inductance structure 301. Therefore, the inductance structure 301 can be set between the pressure sensing structure 200 and the capacitance structure 302, so that the passive device area S2 is sealed by using the pressure sensing structure 200 and the capacitance structure 302 to reduce the use of sealant, which is not limited here.

[0156] In some embodiments, the height of the second inductor lead 302 of the inductor structure 301 may also be the same as the height of the sensing electrode 201 of the pressure sensing structure 200 and the height of the second electrode 3022 of the capacitor structure 302 , which is not limited here.

[0157] Fig.16 The twelfth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention; Fig.17 Thirteenth schematic diagram of the cross-sectional structure of the pressure chip provided in an embodiment of the present invention.

[0158] In a specific implementation, the passive device structure 300 may include other passive devices, such as resistors, in addition to the inductor structure 301 and the capacitor structure 302, which are not limited here. Fig.16 and Fig.17 As shown, a schematic diagram of the cross-sectional structure of the pressure chip including a pressure sensing structure 200, an inductance structure 301, a capacitance structure 302 and a resistance structure 303 is shown. The resistance structure 303 includes a fixed resistor 3031, and the fixed resistor 3031 can have a fixed resistance value. The fixed resistor 3031 and the sensing electrode 201 are located in the same film layer, and the material of the fixed resistor 3031 is the same as that of the sensing electrode 201, and can be manufactured in the same process during manufacturing. The two ends of the fixed resistor 3031 are respectively connected to the connecting pads located on the side of the first surface of the substrate 100 away from the second surface through the connecting structure that penetrates the substrate 100 in the thickness direction. In a specific implementation, the connecting structure for connecting the fixed resistor 3031 to the connecting pad can be set with reference to the inductance structure 301, and will not be repeated here.

[0159] Fig.18 Fourteenth schematic diagram of the cross-sectional structure of the pressure chip provided in an embodiment of the present invention.

[0160] In some embodiments, Figure 2 to Figure 15 As shown, the first cavity D1 of the sensing electrode 201 is a single continuous cavity structure. When the area of ​​the pressure-sensing membrane structure formed by the bottom of the first cavity D1 is small, the first cavity D1 is a single continuous cavity structure to simplify the manufacturing process. The shape of the first cavity D1 can be circular to improve the uniformity of the sensed pressure. The shape of the first cavity D1 can also be square or other shapes, which are not limited here.

[0161] In some embodiments, Fig.18 As shown, the second cavity D2 of the sensing electrode 201 includes a plurality of independent sub-cavities D21, and the plurality of independent sub-cavities D21 are arranged at intervals from each other. The second cavity D2 of the sensing electrode 201 includes a plurality of independent sub-cavities D21, and the size of a single sub-cavity D21 is relatively small. When the area of ​​the pressure-sensitive membrane structure formed by the bottom of the first cavity D1 is relatively large, the second cavity D2 composed of a plurality of sub-cavities D21 can support the pressure-sensitive membrane structure through the sensing electrode 201 between adjacent sub-cavities D21, which can avoid the first cavity D1 from having a large size and unnecessary deformation due to gravity and other reasons, reduce interference with pressure sensing, and improve accuracy. The shape of the sub-cavity D21 can be square or rectangular, and a plurality of sub-cavities D21 are arranged in an array to improve the utilization rate of the sensing electrode 201. The shape of the sub-cavity D21 can also be circular or other shapes, which are not limited here.

[0162] In some embodiments, Fig.18 As shown, the first cavity D1 may also adopt the same structure as the second cavity D2, which is not limited here.

[0163] In some embodiments, Fig.18 As shown, a corresponding first through hole K1 may be provided for each sub-cavity D21 to communicate with the external environment. In some embodiments, only one first through hole K1 with a relatively large opening may be provided, and the orthographic projection of the first through hole K1 on the sensing electrode 201 may at least partially overlap with each sub-cavity D21, so that the pressure-sensing film structure corresponding to each sub-cavity D21 may be communicated with the external environment through the first through hole K1, which is not limited here.

[0164] In some embodiments, Fig.18 As shown, the opposing electrode 202 may include a plurality of spaced-apart sub-opposing electrodes 2021. One of the sub-opposing electrodes 2021 corresponds to a sub-cavity D21, and the sub-opposing electrode 2021 is located within the orthographic projection of the top of the corresponding sub-cavity D21 on the base substrate. In a specific implementation, the side of the base substrate facing away from the glass cover plate includes a plurality of first connecting pads, and one first connecting pad is connected to a corresponding sub-opposing electrode 2021.

[0165] Fig.19 The fifteenth schematic diagram of the cross-sectional structure of the pressure chip provided by the embodiment of the present invention; Fig. 20 The sixteenth schematic diagram of the cross-sectional structure of the pressure chip provided in the embodiment of the present invention.

[0166] In some embodiments, Fig.19 and Fig. 20 As shown, the second conductive layer 20 further includes: a first differential electrode 203, located in the pressure sensing area S1. The first differential electrode 203 and the sensing electrode 201 are arranged side by side and connected to each other. The first conductive layer 10 further includes: a second differential electrode 204, located in the pressure sensing area S1. The second differential electrode 204 and the opposing electrode 202 are arranged to be spaced apart from each other. The orthographic projection of the second differential electrode 204 on the base substrate 100 is located within the orthographic projection of the first differential electrode 203 on the base substrate 100. Along the thickness direction of the base substrate 100, the first differential electrode 203 and the second differential electrode 204 are separated by a third set distance h3 to form a differential capacitor structure.

[0167] The sensing electrode 201, the counter electrode 202, the first differential electrode 203 and the second differential electrode 204 constitute a pressure sensing structure 200. The first differential electrode 203 has a fourth cavity D4 on the side facing the glass cover 500. The orthographic projection of the second differential electrode 204 on the base substrate 100 is located within the orthographic projection of the fourth cavity D4 on the base substrate 100. The glass cover 500 covers the fourth cavity D4, so that a closed space is formed in the fourth cavity D4. In a specific implementation, the first differential electrode 203 has the same structure as the sensing electrode 201, and the second differential electrode 204 has the same structure as the opposing electrode 202, and has similar external conditions such as vibration and temperature. The difference is that the fourth cavity D4 of the first differential electrode 203 forms a closed space with the glass cover 500, so that the capacitance between the first differential electrode 203 and the second differential electrode 204 is not affected by changes in external gas pressure. During the pressure sensing process, a differential operation can be performed through the capacitance between the first differential electrode 203 and the second differential electrode 204 and the capacitance between the sensing electrode 201 and the opposing electrode 202, thereby eliminating the influence of external conditions other than changes in air pressure such as vibration and temperature on the sensed pressure, thereby improving the detection accuracy.

[0168] Figure 21a to Figure 21d A schematic diagram of the manufacturing process of a pressure chip using a glass reflow solution provided in an embodiment of the present invention.

[0169] In some embodiments, the pressure chip provided by the present invention can be manufactured by glass reflux.

[0170] When implementing it, Fig.21aAs shown, a doped first bulk silicon 111 is first provided, and the first bulk silicon 111 is cleaned to form the first conductive layer 10 and the third conductive layer 60. The first conductive layer 10 and the third conductive layer 60 are made of the doped first bulk silicon 111, and the counter electrode, the connection structure, etc. can be directly formed by one etching, and then the substrate 100 is formed by glass reflow. The process is simple, and the connection strength between the first conductive layer 10 and the third conductive layer 60 and the substrate 100 is high and the sealing is good. Then, a plurality of blind grooves F are etched into the first bulk silicon 111 by dry etching or the like (the first bulk silicon 111 is not etched through at the blind grooves F), so as to simultaneously form the counter electrode 202, the first connection structure 601, the second connection structure 602, the first electrode 3021 and the third connection structure 603. Among them, the upper and lower widths of the counter electrode 202 and the first electrode 3021 are consistent, and the width of the counter electrode 202 is smaller than the width of the pressure-sensitive film structure formed on the sensing electrode 201 later. In this embodiment, since the subsequent base substrate 100 (glass) is connected to the second conductive layer 20 (bulk silicon) and the fourth conductive layer 70 by anodic bonding, and the first connection structure 601, the second connection structure 602 and the third connection structure 603 are made of the same material as the second conductive layer 20 (bulk silicon) or the fourth conductive layer 70, anodic bonding cannot be performed, and they are connected by overlapping. There is no bonding force between the overlapping surfaces. When the overlapping surface is too large, it will affect the bonding strength between the second conductive layer 20 and the fourth conductive layer 70 and the base substrate. Therefore, in a specific implementation, the width of each of the tip portions (away from the non-perforated side of the first body silicon 111) of the first connection structure 601, the second connection structure 602 and the third connection structure 603 is smaller than the overall width of the first connection structure 601, so as to reduce the area of ​​the overlapping surface and ensure good connection in the subsequent bonding process. Therefore, after etching the first body silicon 111 to form the opposing electrode 202, the first connection structure 601, the second connection structure 602, the first electrode 3021 and the third connection structure 603, the tips of the first connection structure 601, the second connection structure 602 and the third connection structure 603 can be etched for a second time to reduce the area of ​​the overlapping surface. After etching the first bulk silicon 111, a first glass substrate 112 is provided, and the structures such as the counter electrode 202, the first connection structure 601, the second connection structure 602, the first electrode 3021 and the third connection structure 603 on the first bulk silicon 111 are anodic-bonded to the first glass substrate 112, and annealing is performed after bonding to make the first bulk silicon 111 and the first glass substrate 112 closely fit, which is convenient for the subsequent glass reflow operation. After the first bulk silicon 111 and the first glass substrate 112 are bonded, a glass reflow process is performed in a heating furnace to ensure that the glass is completely filled into the blind groove F, and the surface of the glass is flush with the surface of the first bulk silicon 111 to expose the structures such as the counter electrode 202, and then annealing is performed to form the base substrate 100.

[0171] like Figure 21b As shown, a doped second silicon body 113 is provided, and the second silicon body 113 is used to form the second conductive layer 20 and the fourth conductive layer 70. The second silicon body 113 is etched to form a second cavity D2 and a third cavity D3. Then, the side of the second silicon body 113 formed with the second cavity D2 and the third cavity D3 is anodic bonded to the substrate 100, so that the second silicon body 113 is closely attached to the substrate 100. Then, the side of the second silicon body 113 away from the substrate 100 is thinned, polished, and etched to simultaneously form the sensing electrode 201, the first cavity D1 on the sensing electrode 201, the first inductor lead 2012, and the second electrode 3022.

[0172] like Fig.21c As shown, a second glass substrate 114 is provided, and the second glass substrate 114 is anodically bonded with the sensing electrode 201 and the second electrode 3022, and annealed to encapsulate the pressure chip. Then, the side of the first body silicon 111 away from the second glass substrate 114 is thinned and polished to expose structures such as the counter electrode 202, the first connection structure 601, the second connection structure 602, the first electrode 3021 and the third connection structure 603. The second glass substrate 114 is etched to form a first through hole K1 for connecting the first cavity D1 with the external environment above the first cavity D1 to form a glass cover 500. In specific implementation, the etched area of ​​the second glass substrate 114 can be firstly laser modified, and then the first through hole K1 can be etched by wet etching or dry etching process. In order to save the device size, try to ensure that the inclination angle of the first through hole K1 is greater than 80° (90° is used as an example in the figure).

[0173] like Fig.21dAs shown, after the side of the first body silicon 111 facing away from the second glass substrate 114 is thinned and polished, a protective layer 115 and a metal layer are deposited on the side of the base substrate 100 facing away from the glass cover plate 500. The protective layer 115 is an insulating layer, which can be silicon oxide or silicon nitride or other materials with the same function, and can be deposited by LPCVD or PECVD and other processes, which are not limited here. The metal layer can be copper, aluminum, gold or other metal materials commonly used in semiconductor processes, which are not limited here. The metal layer can be a single-layer structure or a multi-layer structure. For example, the metal layer can include an adhesion layer facing the side of the base substrate to improve the adhesion performance between the metal and the body silicon, which is not limited here. The metal layer is etched to form the second inductor lead 3011 (fifth conductive layer 30). In specific implementation, the metal layer may also be formed with a bonding layer 60 located on the side of the counter electrode 202, the first connection structure 601, the second connection structure 602, the first electrode 3021 and the third connection structure 603 away from the glass cover plate 500, which is used to enhance the bonding strength of the subsequent connection pads. This is not limited here. After the protective layer 115 and the metal layer are deposited, the first connection pad 401, the second connection pad 402, the third connection pad 403, the fourth connection pad 404, the fifth connection pad 405 and the sixth connection pad 406 connected to the counter electrode 202, the first connection structure 601, the second connection structure 602, the first electrode 3021 and the third connection structure 603 are respectively formed on the side of the metal layer away from the glass cover plate 500. In a specific implementation, the first connection pad 401 , the second connection pad 402 , the third connection pad 403 , the fourth connection pad 404 , the fifth connection pad 405 and the sixth connection pad 406 may be solder balls, which is not limited here.

[0174] Figure 22a to Figure 22c A schematic diagram of the manufacturing process of a pressure chip using a glass perforation solution provided in an embodiment of the present invention.

[0175] In some embodiments, the pressure chip provided by the present invention can be manufactured by glass perforation.

[0176] When implementing it, Fig.22aAs shown, first, a third glass substrate 116 is provided, and the third glass substrate 116 is cleaned for making the base substrate 100. Then, the third glass substrate 116 is etched by glass modification-wet etching or high-voltage discharge to make the second through hole K2, the third through hole K3, the fourth through hole K4, the fifth through hole K5 and the sixth through hole K6 to form the base substrate 100. In order to save the device size, it is ensured that the inclination angles of the second through hole K2, the third through hole K3, the fourth through hole K4, the fifth through hole K5 and the sixth through hole K6 are greater than 80° (90° is used as an example in the figure). During the specific production, the second through hole K2, the third through hole K3, the fourth through hole K4, the fifth through hole K5 and the sixth through hole K6 can be etched unidirectionally from one side of the third glass substrate 116, or etched simultaneously from the opposite sides of the third glass substrate 116 to improve the etching efficiency, which is not limited here. When etching is performed simultaneously from two opposite sides of the third glass substrate 116, the etching direction is directed from the two sides of the third glass substrate 116 to the middle layer of the third glass substrate 116. Due to etching deviation, the size of the through hole on the surface of the glass substrate is larger than the size in the middle of the glass substrate. After etching the third glass substrate 116 to form through holes, a metal layer 117 is grown inside the second through hole K2, the third through hole K3, the fourth through hole K4, the fifth through hole K5, and the sixth through hole K6 and on the surface of the third glass substrate 116 by thin film deposition or the like, and the metal material completely fills the second through hole K2, the third through hole K3, the fourth through hole K4, the fifth through hole K5, and the sixth through hole K6, so as to form the first connection structure 601, the second connection structure 602, the third connection structure 603, the fourth connection structure 604, and the fifth connection structure 605 accordingly. In a specific implementation, before forming the metal layer 117, an adhesion layer or a seed layer may be formed in advance on the inner walls of the second through hole K2, the third through hole K3, the fourth through hole K4, the fifth through hole K5 and the sixth through hole K6 and the surface of the third glass substrate 116 by thin film deposition or the like, so as to improve the adhesion performance between the metal layer 117 and the third glass substrate 116. After forming the metal layer 117, the metal layer on the first surface 101 and the second surface 102 of the base substrate 100 is etched to form the counter electrode 202, the first inductor lead 3012, the second inductor lead 3011 and the first electrode 3021. In a specific implementation, a bonding layer may be formed at the corresponding positions of the first connection structure 601, the second connection structure 602, the third connection structure 603, the fourth connection structure 604 and the fifth connection structure 605 away from the counter electrode 202 by etching the metal layer 117, so as to improve the adhesion performance of the connection pad when the connection pad is subsequently manufactured.

[0177] like Figure 22bAs shown, a doped third silicon body 118 is provided, and the doped third silicon body 118 is etched to form a second cavity D2 and a third cavity D3, and a recessed portion 704. The depth of the recessed portion 704 is greater than the height of the first inductor lead 3012, and is used to accommodate the first inductor lead 3012 when the third silicon body 118 is bonded to the substrate 100. Then, the side of the third silicon body 118 where the second cavity D2 and the third cavity D3 are formed faces the side of the substrate 100 where the counter electrode 202 is provided, and anodically bonds are performed, so that the second cavity D2 corresponds to the counter electrode 202, and the third cavity D3 corresponds to the first electrode 3021. After the third body silicon 118 is bonded to the substrate 100 , the side of the third body silicon 118 away from the substrate 100 is thinned, polished, and etched to form the sensing electrode 201 , the first cavity D1 on the sensing electrode 201 , and the second electrode 3022 , and the second inductor lead 3011 is exposed.

[0178] like Fig.22c As shown, a fourth glass substrate is provided, and the fourth glass substrate is anodically bonded to the sensing electrode 201 and the second electrode 3022 to encapsulate the pressure sensing structure and the passive device structure. After the fourth glass substrate is bonded to the sensing electrode 201 and the second electrode 3022, the fourth glass substrate is etched to form a first through hole K1 for connecting the first cavity D1 with the external environment above the first cavity D1 to form a glass cover 500. In specific implementation, the etched area can be first laser modified, and then the first through hole K1 is etched by a wet etching or dry etching process. In order to save device size, try to ensure that the inclination angle of the first through hole K1 is greater than 80° (90° is used as an example in the figure). Finally, the first connection pad 401, the second connection pad 402, the third connection pad 403, the fourth connection pad 404, the fifth connection pad 405 and the sixth connection pad 406 are made on the side of the metal layer away from the glass cover plate, which are respectively electrically connected to the fourth connection structure 604, the first connection structure 601, the second connection structure 602, the fifth connection structure 605 and the third connection structure 603. In a specific implementation, the first connection pad 401, the second connection pad 402, the third connection pad 403, the fourth connection pad 404, the fifth connection pad 405 and the sixth connection pad 406 can be solder balls, which is not limited here.

[0179] In specific implementation, according to the specific structure of the pressure chip, the manufacturing steps can be reasonably increased or decreased by referring to the manufacturing process of the above-mentioned pressure chip, which will not be elaborated here.

[0180] Fig.23 A schematic diagram of the cross-sectional structure of a pressure sensor provided by an embodiment of the present invention.

[0181] A second aspect of the embodiments of the present invention further provides a pressure sensor, such as Fig.23 As shown, the pressure sensor includes a signal processing circuit 2 and a pressure chip 1 provided in any of the above embodiments. The pressure chip 1 is electrically connected to the signal processing circuit 2 to form a complete pressure sensor. In specific implementation, the signal processing circuit can be a chip or circuit board such as an ASIC chip, a field programmable gate array (Field Programmable Gate Array, referred to as FPGA), a printed circuit board (Printed Circuit Board, referred to as PCB) with computing functions, etc., which is not limited here. In an embodiment of the present invention, a first conductive layer 10 and a second conductive layer 20, and a third conductive layer 60 and a fourth conductive layer 70, which are oppositely arranged, can be formed on the substrate of the pressure chip, and a pressure sensing structure 200 and a passive device structure 300 can be simultaneously manufactured, so that at least one passive device structure 300 (capacitor, inductor, resistor, etc.) in the signal processing circuit in the prior art is integrated into the pressure chip 200, and then the passive device 300 integrated in the pressure chip 200 is electrically connected to the signal processing circuit to form a complete signal processing circuit. Compared with the prior art, the structure of the signal processing circuit can be greatly simplified and the design difficulty can be reduced. By using a pressure chip with an integrated passive device structure, the pressure sensing structure 200 and the passive device structure 300 can be bonded to the signal processing circuit and packaged at the same time, which is beneficial to reduce the packaging difficulty and the volume of the packaged pressure sensor, thereby achieving further miniaturization of the pressure sensor.

[0182] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0183] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A pressure chip, characterized in that: include: substrate substrate; The base substrate comprises a first surface and a second surface opposite to each other in a thickness direction, and a plurality of through holes extending from the first surface to the second surface; A first conductive layer and a third conductive layer; the first conductive layer and the third conductive layer are located in the same film layer and are at least located in the through hole; A second conductive layer and a fourth conductive layer; the second conductive layer and the fourth conductive layer are located in the same film layer and are located on a side of the second surface facing away from the first surface; The first surface includes a non-overlapping pressure sensing area and a passive device area; in the pressure sensing area, the first conductive layer and the second conductive layer form a pressure sensing structure; in the passive device area, the third conductive layer and the fourth conductive layer form a passive device structure.

2. The pressure chip according to claim 1, characterized in that: The material of the substrate is glass.

3. The pressure chip according to claim 2, characterized in that: The material of the second conductive layer and the material of the fourth conductive layer are both doped bulk silicon.

4. The pressure chip according to claim 3, characterized in that: Also includes: A glass cover is located on a side of the second conductive layer and the fourth conductive layer away from the base substrate; the orthographic projection of the glass cover on the base substrate covers the orthographic projection of the pressure sensing structure on the base substrate and the orthographic projection of the passive device structure on the base substrate.

5. The pressure chip according to claim 4, characterized in that: Also includes: A connecting pad is located on a side of the first surface facing away from the second surface; the pressure sensing structure and the passive device structure are electrically connected to the connecting pad; and the connecting pad is used to connect to a signal processing circuit to form a pressure sensor.

6. The pressure chip according to claim 5, characterized in that: In the pressure sensing area, the first conductive layer includes an opposing electrode, and the second conductive layer includes a sensing electrode; an orthographic projection of the opposing electrode on the base substrate is located within an orthographic projection of the sensing electrode on the base substrate; Along the thickness direction of the base substrate, the counter electrode is spaced a first set distance from the sensing electrode to form the pressure sensing structure; The surface of the sensing electrode facing away from the substrate has a first cavity; The orthographic projection of the counter electrode on the base substrate is located within the orthographic projection of the bottom of the first cavity on the base substrate; the thickness of the sensing electrode in the corresponding area of ​​the bottom of the first cavity is smaller than the thickness of the sensing electrode around the bottom of the first cavity; The glass cover plate includes a first through hole penetrating the glass cover plate along a thickness direction; the orthographic projection of the first through hole on the base substrate is located within the orthographic projection of the first cavity on the base substrate, so that the first cavity is connected to the external environment through the first through hole.

7. The pressure chip according to claim 6, characterized in that: The material of the first conductive layer and the material of the third conductive layer are both doped bulk silicon; The through hole comprises a second through hole and a third through hole which are arranged at intervals; the connecting pad comprises a first connecting pad and a second connecting pad; wherein the first connecting pad is located at a position corresponding to the second through hole, and the second connecting pad is located at a position corresponding to the third through hole; The second through hole and the third through hole are located in the pressure sensing area; the counter electrode is filled in the second through hole and is electrically connected to the first connecting pad; The first conductive layer further comprises: A first connecting structure, located in the third through hole; One end of the first connection structure is electrically connected to the sensing electrode, and the other end of the first connection structure is electrically connected to the second connection pad.

8. The pressure chip according to claim 7, characterized in that: Within the range covered by the orthographic projection of the sensing electrode on the substrate, the second surface is a plane; The surface of the sensing electrode facing the base substrate has a second cavity; the second cavity is used to make the opposing electrode and the sensing electrode be at the first set distance along the thickness direction of the base substrate; The orthographic projection of the second cavity on the base substrate coincides with the orthographic projection of the first cavity on the base substrate; The sensing electrodes around the second cavity are in contact with the second surface of the base substrate, so that a closed space is formed in the second cavity.

9. The pressure chip according to claim 7, characterized in that: The second surface of the base substrate comprises a first groove; the first groove is located within the orthographic projection of the sensing electrode on the base substrate, and the orthographic projection of the bottom of the first cavity on the base substrate is located within the region where the first groove is located; the second through hole is located in the first groove; The surface of the sensing electrode facing the base substrate is a plane, and the first groove is used to make the opposing electrode and the sensing electrode separated by the first set distance along the thickness direction of the base substrate; the sensing electrodes around the first groove are in contact with the second surface of the base substrate, so that a closed space is formed in the first groove.

10. The pressure chip according to any one of claims 7 to 9, characterized in that: The passive device structure includes an inductor structure; The through hole further includes a plurality of fourth through holes; the connecting pad further includes a third connecting pad and a fourth connecting pad; A plurality of the fourth through holes are located in the passive device area; The third conductive layer comprises: A plurality of second connection structures, located in the fourth through hole; The fourth conductive layer comprises: A plurality of first inductor leads are located on a side of the second surface facing away from the first surface and located in the passive device area; The pressure chip also includes: a fifth conductive layer, located on a side of the first surface away from the second surface; the material of the fifth conductive layer is metal; the fifth conductive layer includes a plurality of second inductor leads; the second inductor leads are located in the passive device area; The second connection structure is used to connect the first inductor lead and the second inductor lead end to end to form the inductor structure; one end of the inductor structure is electrically connected to the third connection pad, and the other end is electrically connected to the fourth connection pad.

11. The pressure chip according to any one of claims 7 to 9, characterized in that: The passive device structure includes a capacitor structure; The through hole further includes a fifth through hole and a sixth through hole which are arranged at intervals; the connecting pad further includes a fifth connecting pad and a sixth connecting pad; wherein the fifth connecting pad is located at a position corresponding to the fifth through hole, and the sixth connecting pad is located at a position corresponding to the sixth through hole; The fifth through hole and the sixth through hole are located in the passive device area; The third conductive layer comprises: A first electrode; the first electrode is located in the fifth through hole and is electrically connected to the fifth connection pad; A third connecting structure is located in the sixth through hole; The fourth conductive layer includes: a second electrode located in the passive device region; The orthographic projection of the second electrode on the base substrate covers the first electrode; along the thickness direction of the base substrate, the second electrode is separated from the first electrode by a second set distance to form the capacitor structure; one end of the third connection structure is electrically connected to the second electrode, and the other end is connected to the sixth connection pad.

12. The pressure chip according to claim 11, characterized in that: Within the range covered by the orthographic projection of the second electrode on the substrate, the second surface is a plane; The surface of the second electrode facing the base substrate has a third cavity; the third cavity is used to make the second electrode and the first electrode separated by the second set distance along the thickness direction of the base substrate; the orthographic projection of the third cavity on the base substrate covers the fifth through hole; the second electrode around the third cavity contacts the second surface of the base substrate, so that a closed space is formed in the third cavity; or, The second surface of the base substrate further includes a second groove; the second groove is located within the orthographic projection of the second electrode on the base substrate; the fifth through hole is located in the second groove; The surface of the second electrode facing the base substrate is a plane, and the second groove is used to make the second electrode and the first electrode separated by the second set distance along the thickness direction of the base substrate; the second electrode around the second groove is in contact with the second surface of the base substrate, so that a closed space is formed in the second groove.

13. The pressure chip according to claim 6, characterized in that: The material of the first conductive layer and the material of the third conductive layer are both metal; The through hole comprises a second through hole and a third through hole which are arranged at intervals; the connecting pad comprises a first connecting pad and a second connecting pad; wherein the first connecting pad is located at a position corresponding to the second through hole, and the second connecting pad is located at a position corresponding to the third through hole; the second through hole is located within the orthographic projection of the counter electrode on the substrate; The second through hole and the third through hole are located in the pressure sensing area; The first conductive layer further comprises: a fourth connection structure, located in the second through hole; the counter electrode is located on a side of the fourth connection structure away from the first surface; one end of the fourth connection structure is connected to the counter electrode, and the other end is connected to the first connection pad; A first connection structure is located in the third through hole; one end of the first connection structure is electrically connected to the sensing electrode, and the other end of the first connection structure is electrically connected to the second connection pad.

14. The pressure chip according to claim 13, characterized in that: Within the range covered by the orthographic projection of the sensing electrode on the substrate, the second surface is a plane; The surface of the sensing electrode facing the base substrate has a second cavity; the second cavity is used to make the opposing electrode and the sensing electrode be at the first set distance along the thickness direction of the base substrate; The orthographic projection of the second cavity on the base substrate coincides with the orthographic projection of the first cavity on the base substrate; The sensing electrodes around the second cavity are in contact with the second surface of the base substrate, so that a closed space is formed in the second cavity.

15. The pressure chip according to claim 13, characterized in that: The second surface of the base substrate comprises a first groove; the first groove is located within the orthographic projection of the sensing electrode on the base substrate, and the orthographic projection of the bottom of the first cavity on the base substrate is located within the region where the first groove is located; the counter electrode is located in the first groove, and the second through hole is located in the first groove; the surface of the sensing electrode facing the base substrate is a plane, and the first groove is used to make the counter electrode and the sensing electrode separated by the first set distance along the thickness direction of the base substrate; the sensing electrodes around the first groove are in contact with the second surface of the base substrate, so that a closed space is formed in the first groove.

16. The pressure chip according to any one of claims 13 to 15, characterized in that: The passive device structure includes an inductor structure; The through hole includes a plurality of fourth through holes; the connecting pads also include a third connecting pad and a fourth connecting pad; A plurality of the fourth through holes are located in the passive device area; The third conductive layer further comprises: A plurality of first inductor leads are located on a side of the second surface facing away from the first surface and located in the passive device area; A plurality of second inductor leads, located on a side of the first surface facing away from the second surface and located in the passive device area; A plurality of second connection structures are located in the fourth through hole; the second connection structures are used to connect the first inductor lead wire and the second inductor lead wire end to end to form the inductor structure; Wherein, one end of the inductor structure is electrically connected to the third connection pad, and the other end is electrically connected to the fourth connection pad.

17. The pressure chip according to any one of claims 13 to 15, characterized in that: The passive device structure also includes a capacitor structure; The through hole further includes a fifth through hole and a sixth through hole which are arranged at intervals; the connecting pad further includes a fifth connecting pad and a sixth connecting pad; wherein the fifth connecting pad is located at a position corresponding to the fifth through hole, and the sixth connecting pad is located at a position corresponding to the sixth through hole; The fifth through hole and the sixth through hole are located in the passive device area; The third conductive layer further comprises: a fifth connecting structure, located in the fifth through hole; a first electrode, located at a side of the fifth connection structure away from the first surface; an orthographic projection of the first electrode on the substrate covers the fifth through hole; one end of the fifth connection structure is electrically connected to the first electrode, and the other end is connected to the fifth connection pad; A third connecting structure is located in the sixth through hole; The fourth conductive layer also includes: a second electrode, located in the passive device area; the orthographic projection of the second electrode on the substrate covers the first electrode; along the thickness direction of the substrate, the second electrode is separated from the first electrode by a second set distance to form the capacitor structure; one end of the third connection structure is electrically connected to the second electrode, and the other end is connected to the sixth connection pad.

18. The pressure chip according to claim 17, characterized in that: Within the range of the orthographic projection of the second electrode on the substrate, the second surface is a plane; The surface of the second electrode facing the substrate has a third cavity; the orthographic projection of the third cavity on the substrate covers the orthographic projection of the first electrode on the substrate; the third cavity is used to make the second electrode and the first electrode separated by the second set distance along the thickness direction of the substrate; the second electrodes around the third cavity are in contact with the second surface of the substrate, so that a closed space is formed in the third cavity; or, The second surface of the base substrate also includes a second groove; the second groove is located within the orthographic projection of the second electrode on the base substrate; the fifth through hole and the first electrode are both located in the second groove; the surface of the second electrode facing the base substrate is a plane, and the second groove is used to make the second electrode and the first electrode separated by the second set distance along the thickness direction of the base substrate; the second electrode around the second groove is in contact with the second surface of the base substrate, so that a closed space is formed in the second groove.

19. The pressure chip according to claim 6, characterized in that: The second conductive layer further comprises: A first differential electrode is located in the pressure sensing area; the first differential electrode and the sensing electrode are arranged side by side and connected to each other; The first conductive layer further comprises: a second differential electrode, located in the pressure sensing area; the second differential electrode and the counter electrode are spaced from each other; the orthographic projection of the second differential electrode on the base substrate is located within the orthographic projection of the first differential electrode on the base substrate; along the thickness direction of the base substrate, the first differential electrode and the second differential electrode are separated by a third set distance; the sensing electrode, the counter electrode, the first differential electrode and the second differential electrode constitute the pressure sensing structure; The first differential electrode has a fourth cavity on the side facing the glass cover plate; the orthographic projection of the second differential electrode on the base substrate is located within the orthographic projection of the fourth cavity on the base substrate; and the glass cover plate covers the fourth cavity so that the fourth cavity forms a closed space.

20. A pressure sensor, characterized in that: It comprises a signal processing circuit and a pressure chip as described in any one of claims 1 to 19, wherein the pressure chip is electrically connected to the signal processing circuit.

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