A high-sensitivity high-frequency-response graphene pressure sensor

Abstract

The application belongs to the technical field of pressure sensors, and particularly relates to a high-sensitivity and high-frequency-response graphene pressure sensor. A cap is arranged on a packaging shell, a ceramic base is arranged at the bottom of the packaging shell, a detection substrate is bonded to the upper portion of the ceramic base, a cavity is etched at the lower portion of the detection substrate, first, second, third and fourth elastic beams are connected with the detection substrate, and first, second, third and fourth non-penetrating holes are etched at the connecting portions of the first, second, third and fourth elastic beams and the detection substrate. The application creatively introduces a center island and a non-penetrating hole structure on the basis of a common cross beam structure. Under the same pressure, the strain sensed by the nanometer detection unit in the sensor is larger, the sensitivity of the sensor is greatly improved, the structural rigidity of the pressure sensor is improved under a proper structure size, and the inherent frequency of the sensor itself is further improved.

Description

Technical Field

[0001] This invention belongs to the field of pressure sensor technology, specifically relating to a high-sensitivity, high-frequency response graphene pressure sensor. Background Technology

[0002] Sensor technology is one of the most important technologies in modern measurement and automation systems. From space exploration to ocean depths, from production process control to modern daily life, almost every technology relies on sensors. Therefore, many countries attach great importance to the development of sensor technology.

[0003] Among various types of sensors, pressure sensors have the advantages of small size, light weight, high sensitivity, stability and reliability, low cost, and easy integration. They can be widely used for the measurement and control of pressure, altitude, acceleration, liquid flow rate, velocity, liquid level, and pressure. In addition, they are widely used in water conservancy, geology, meteorology, chemical industry, and medical and health fields. Pressure sensors have become one of the most technologically mature, stable, and cost-effective types of sensors.

[0004] Based on different operating principles, pressure sensors can be classified into resistance strain gauge pressure sensors, semiconductor strain gauge pressure sensors, piezoresistive pressure sensors, inductive pressure sensors, capacitive pressure sensors, resonant pressure sensors, fiber optic pressure sensors, and capacitive accelerometers. Compared with other types of sensors such as capacitive, fiber optic, and resonant sensors, piezoresistive pressure sensors have advantages such as small size, simple manufacturing process, and wide linear range.

[0005] Since its emergence, graphene, a two-dimensional material, has attracted much attention in the field of MEMS sensors due to its excellent electrical, thermal and mechanical properties. Because of its excellent piezoresistive effect and extremely high compatibility with MEMS processes, it has become the preferred material for pressure sensor sensitive units and is widely regarded as an excellent pressure-sensitive material for making high-sensitivity, fast-response, and large-range sensors.

[0006] In many applications, pressure sensors require both high sensitivity and high frequency response. Generally, improving sensor sensitivity can be achieved by reducing its structural stiffness; however, reducing structural stiffness leads to a decrease in the sensor's natural frequency. Currently popular piezoresistive pressure sensors, while achieving high sensitivity, cannot achieve a high natural frequency, and vice versa; pursuing a high natural frequency makes it difficult to meet the demand for high sensitivity. Therefore, resolving the contradiction between sensitivity and natural frequency is a key technical challenge that urgently needs to be overcome to ensure reliable and accurate measurement by piezoresistive pressure sensors. Summary of the Invention

[0007] To address the technical problem of the contradiction between sensitivity and inherent frequency mentioned above, this invention provides a high-sensitivity, high-frequency response graphene pressure sensor, aiming to solve the coupling problem between the sensitivity and inherent frequency of existing pressure sensors.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0009] A high-sensitivity, high-frequency response graphene pressure sensor includes a packaging shell, a ceramic substrate, a detection substrate, a nano-detection unit, a pressure-transmitting silicon membrane, a cap, a first elastic beam, a second elastic beam, a third elastic beam, a fourth elastic beam, a first non-penetrating hole, a second non-penetrating hole, a third non-penetrating hole, a fourth non-penetrating hole, and a welding metal. The packaging shell is bonded or welded to the cap via the welding metal. A ceramic substrate is installed at the bottom of the packaging shell. The detection substrate is bonded to the upper part of the ceramic substrate. A cavity is etched in the lower part of the detection substrate to form a central island and the first, second, third, and fourth elastic beams. The first, second, third, and fourth elastic beams are all connected to the detection substrate. The first, second, third, and fourth non-penetrating holes are etched at the connection points between the first, second, third, and fourth elastic beams and the detection substrate, respectively.

[0010] A pressure-transmitting silicon film is bonded to the upper part of the detection substrate. Cavities are etched on both the upper and lower parts of the pressure-transmitting silicon film. A protrusion is etched on the lower surface of the pressure-transmitting silicon film. The protrusion is bonded to the central island by a bonding metal. The pressure-transmitting silicon film is bonded to the detection substrate by a first metal sealing ring and a second metal sealing ring. The lower part of the detection substrate is bonded to the ceramic substrate by a third metal sealing ring. The cap is bonded or welded to the packaging shell. The cap has a through-hole structure, which is circular or square in shape.

[0011] The diagonals of the central island pass through the midlines of the first, second, third, and fourth elastic beams, respectively, and the four corner points of the central island are located on the axial midlines of the upper surfaces of the first, second, third, and fourth elastic beams, respectively.

[0012] The line connecting the geometric center point of the upper surface of the central island with the geometric center points of the upper surfaces of the first non-penetrating hole, the second non-penetrating hole, the third non-penetrating hole, and the fourth non-penetrating hole coincides with the axial centerline of the upper surface of the first elastic beam, the second elastic beam, the third elastic beam, and the fourth elastic beam.

[0013] The nano-detection unit is provided in four parts, which surround the first non-penetrating hole, the second non-penetrating hole, the third non-penetrating hole, and the fourth non-penetrating hole, respectively. The four nano-detection units are composed of the first nano-detection unit, the second nano-detection unit, the third nano-detection unit, and the fourth nano-detection unit.

[0014] The first nanoscale detection unit comprises a first graphene varistor, a first top protective layer, and a first bottom protective layer, with the first graphene varistor disposed between the first top protective layer and the first bottom protective layer; the second nanoscale detection unit comprises a second graphene varistor, a second top protective layer, and a second bottom protective layer, with the second graphene varistor disposed between the second top protective layer and the second bottom protective layer; the third nanoscale detection unit comprises a third graphene varistor, a third top protective layer, and a third bottom protective layer, with the third graphene varistor disposed between the third top protective layer and the third bottom protective layer; and the fourth nanoscale detection unit comprises a fourth graphene varistor, a fourth top protective layer, and a fourth bottom protective layer, with the fourth graphene varistor disposed between the fourth top protective layer and the fourth bottom protective layer.

[0015] The first nano-detection unit is connected to the first internal interconnect electrode and the second internal interconnect electrode via the first internal interconnect lead and the second internal interconnect lead. The second nano-detection unit is connected to the third internal interconnect electrode and the fourth internal interconnect electrode via the third internal interconnect lead and the fourth internal interconnect lead. The third nano-detection unit is connected to the fifth internal interconnect electrode and the sixth internal interconnect electrode via the fifth internal interconnect lead and the sixth internal interconnect lead. The fourth nano-detection unit is connected to the seventh internal interconnect electrode and the eighth internal interconnect electrode via the seventh internal interconnect lead and the eighth internal interconnect lead.

[0016] The first internal interconnect electrode is connected via a first external interconnect lead and a first interconnect bump; the second internal interconnect electrode is connected via a second external interconnect lead and a second interconnect bump; the third internal interconnect electrode is connected via a third external interconnect lead and a third interconnect bump; the fourth internal interconnect electrode is connected via a fourth external interconnect lead and a fourth interconnect bump; the fifth internal interconnect electrode is connected via a fifth external interconnect lead and a fifth interconnect bump; the sixth internal interconnect electrode is connected via a sixth external interconnect lead and a sixth interconnect bump; the seventh internal interconnect electrode is connected via a seventh external interconnect lead and a seventh interconnect bump; and the eighth internal interconnect electrode is connected via an eighth external interconnect lead and an eighth interconnect bump.

[0017] The first interconnect bump is connected to the first interconnect pad, the second interconnect bump is connected to the second interconnect pad, the third interconnect bump is connected to the third interconnect pad, the fourth interconnect bump is connected to the fourth interconnect pad, the fifth interconnect bump is connected to the fifth interconnect pad, the sixth interconnect bump is connected to the sixth interconnect pad, the seventh interconnect bump is connected to the seventh interconnect pad, and the eighth interconnect bump is connected to the eighth interconnect pad.

[0018] The first interconnect pad is connected to the first external interconnect electrode via a first lead post; the second interconnect pad is connected to the second external interconnect electrode via a second lead post; the third interconnect pad is connected to the third external interconnect electrode via a third lead post; the fourth interconnect pad is connected to the fourth external interconnect electrode via a fourth lead post; the fifth interconnect pad is connected to the fifth external interconnect electrode via a fifth lead post; the sixth interconnect pad is connected to the sixth external interconnect electrode via a sixth lead post; the seventh interconnect pad is connected to the seventh external interconnect electrode via a seventh lead post; and the eighth interconnect pad is connected to the eighth external interconnect electrode via an eighth lead post. All external interconnect electrodes (first, second, third, fourth, fifth, sixth, seventh, and eighth) are connected to external resistors. The nano-detection unit itself or together with an external resistor forms a Wheatstone half-bridge or a full-bridge.

[0019] Compared with the prior art, the beneficial effects of this invention are:

[0020] This invention addresses the limitation of simultaneously improving sensor sensitivity and natural frequency by proposing an innovative improvement scheme. The invention cleverly introduces a central island and a non-penetrating hole structure. This design significantly increases the strain that the nano-detection units within the pressure sensor can sense under the same pressure, making the sensor's strain response more sensitive and its output signal stronger under the same pressure, thereby improving the sensor's sensitivity. Simultaneously, this structure effectively improves the sensor's structural stiffness, thus increasing its natural frequency. This invention simultaneously improves both the sensor's sensitivity and natural frequency, effectively enhancing the performance of the pressure sensor. Attached Figure Description

[0021] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0022] The structures, proportions, sizes, etc. illustrated in this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0023] Figure 1 This is a three-dimensional schematic diagram of the appearance of Embodiment 1 of the present invention;

[0024] Figure 2 This is a schematic diagram of the transverse cross-sectional structure of Embodiment 1 of the present invention;

[0025] Figure 3 This is a schematic diagram of the longitudinal cross-sectional structure of Embodiment 1 of the present invention;

[0026] Figure 4 This is a top view of the internal structure of Embodiment 1 of the present invention;

[0027] Figure 5 This is a schematic diagram of the cross-sectional structure of the nano-detection unit according to Embodiment 1 of the present invention;

[0028] Figure 6 This is a top view of the nano-detection unit structure installed according to an embodiment of the present invention;

[0029] Figure 7 This is a top view of the internal structure of Embodiment 2 of the present invention;

[0030] Figure 8 This is a top view of the internal structure of Embodiment 3 of the present invention;

[0031] Figure 9 This is a three-dimensional front view of the detection substrate according to Embodiment 1 of the present invention;

[0032] Figure 10 This is a three-dimensional view of the back side of the detection substrate in Embodiment 1 of the present invention.

[0033] Wherein: 1 is the pressure-transmitting silicon film, 2 is the first metal sealing ring, 3 is the second metal sealing ring, 4-1 is the first internal interconnect electrode, 4-2 is the connection of the second internal interconnect electrode, 4-3 is the third internal interconnect electrode, 4-4 is the fourth internal interconnect electrode, 4-5 is the fifth internal interconnect electrode, 4-6 is the connection of the sixth internal interconnect electrode, 4-7 is the seventh internal interconnect electrode, 4-8 is the eighth internal interconnect electrode, 5-1 is the first external interconnect lead, 5-2 is the second external interconnect lead, 5-3 is the third external interconnect lead, 5-4 is the fourth external interconnect lead, 5-5 is the fifth external interconnect lead, 5-6 is the sixth external interconnect lead, 5-7 is the seventh external interconnect lead, 5-8 is the eighth external interconnect lead, 6-1 is the first... 6-1 is the first interconnect bump, 6-2 is the second interconnect bump, 6-3 is the third interconnect bump, 6-4 is the fourth interconnect bump, 6-5 is the fifth interconnect bump, 6-6 is the sixth interconnect bump, 6-7 is the seventh interconnect bump, 6-8 is the eighth interconnect bump, 7-1 is connected to the first interconnect pad, 7-2 is the second interconnect pad, 7-3 is the third interconnect pad, 7-4 is the fourth interconnect pad, 7-5 is the fifth interconnect pad, 7-6 is the sixth interconnect pad, 7-7 is the seventh interconnect pad, 7-8 is the eighth interconnect pad, 8-1 is the first lead post, 8-2 is the second lead post, 8-3 is the third lead post, 8-4 is the fourth lead post, 8-5 is the fifth lead post, 8-6 is the sixth lead post, 8-7 is the seventh lead post, 8-8 is... The eighth lead post; 9-1 is the first external interconnect electrode; 9-2 is the second external interconnect electrode; 9-3 is the third external interconnect electrode; 9-4 is the fourth external interconnect electrode; 9-5 is the fifth external interconnect electrode; 9-6 is the sixth external interconnect electrode; 9-7 is the seventh external interconnect electrode; 9-8 is the eighth external interconnect electrode; 10 is the third metal sealing ring; 11-1 is the first non-penetrating hole; 11-2 is the second non-penetrating hole; 11-3 is the third non-penetrating hole; 11-4 is the fourth non-penetrating hole; 12 is the package housing; 13-1 is the first elastic beam; 13-2 is the second elastic beam; 13-3 is the third elastic beam; 13-4 is the fourth elastic beam; 14 is the central island; 15 is the detection substrate; 16 is the ceramic base; 17 is... Cap, 18 is bonding metal, 19 is a protrusion, 20-1 is the first internal interconnect lead, 20-2 is the second internal interconnect lead, 20-3 is the third internal interconnect lead, 20-4 is the fourth internal interconnect lead, 20-5 is the fifth internal interconnect lead, 20-6 is the sixth internal interconnect lead, 20-7 is the seventh internal interconnect lead, 20-8 is the eighth internal interconnect lead, 21 is solder metal, 22 is a through hole, 23-1 is the first top protective layer, 23-2 is the second top protective layer, 23-3 is the third top protective layer, 23-4 is the fourth top protective layer, 24-1 is the first bottom protective layer, 24-2 is the second bottom protective layer, 24-3 is the third bottom protective layer, 24-4 is the fourth top protective layer.25-1 is the first graphene varistor, 25-2 is the second graphene varistor, 25-3 is the third graphene varistor, and 25-4 is the fourth graphene varistor. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. These descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the claims of the present invention. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0035] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0036] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0037] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0038] Example 1

[0039] Combination Figures 1-7 , Figure 9 and Figure 10In this embodiment, the encapsulation shell 12 is bonded or welded to the cap 17 via welding metal 21. A ceramic base 16 is mounted at the bottom of the encapsulation shell 12. A detection substrate 15 is bonded to the upper part of the ceramic base 16. A cavity is etched into the lower part of the detection substrate 15, forming a central island 14 and a first elastic beam 13-1, a second elastic beam 13-2, a third elastic beam 13-3, and a fourth elastic beam 13-4. The central island 14 is square, and the connections between the central island 14 and the first elastic beam 13-1, the second elastic beam 13-2, the third elastic beam 13-3, and the fourth elastic beam 13-4 are rounded. The connections between the first elastic beam 13-1, the second elastic beam 13-2, the third elastic beam 13-3, the fourth elastic beam 13-4 and the detection substrate 15 are... The surface is etched with a first non-penetrating via 11-1, a second non-penetrating via 11-2, a third non-penetrating via 11-3, and a fourth non-penetrating via 11-4. These four vias surround four nano-detection units. Each nano-detection unit consists of a sandwich structure formed by a top protective layer, a graphene varistor, and a bottom protective layer. The first graphene varistor 25-1, the second graphene varistor 25-2, the third graphene varistor 25-3, and the fourth graphene varistor 25-4 are all U-shaped. The widths of the first non-penetrating via 11-1, the second non-penetrating via 11-2, the third non-penetrating via 11-3, and the fourth non-penetrating via 11-4 are set to... The depths of the elastic beams 13-1, 13-2, 13-3, and 13-4 are all less than those of the first elastic beam 13-1, the second elastic beam 13-2, the third elastic beam 13-3, and the fourth elastic beam 13-4. A pressure-transmitting silicon film 1 is bonded to the upper part of the detection substrate 15. Cavities are etched on both the upper and lower parts of the pressure-transmitting silicon film 1, and a protrusion 19 is etched on the lower surface. The protrusion 19 is bonded to the central island 14 via a bonding metal 18. The pressure-transmitting silicon film 1 is bonded to the detection substrate 15 via a first metal sealing ring 2 and a second metal sealing ring 3. The lower part of the detection substrate 15 is bonded to the ceramic substrate 16 via a third metal sealing ring 10. A cap 17 is bonded or welded to the encapsulation shell 12, and the cap 17 has a through-hole structure 22. The shape of the through-hole 22 is not limited to the circular shape shown in this invention; it can also be square or other shapes. Specifically, the cap 17, pressure-transmitting silicon membrane 1, encapsulation shell 12, and ceramic substrate 16 together define an internal detection space. The detection component proposed in this invention is set within the internal detection space. Pressure is transmitted through the pressure-transmitting silicon membrane 1 to the protrusion 19, which then transmits the pressure to the central island 14. The central island 14 causes four elastic beams to deform, and the nano-detection unit set at the connection between the elastic beams and the detection substrate 15 deforms. The graphene piezoresistor within it will change proportionally to the strain, breaking the Wheatstone bridge balance and generating an electrical signal in the circuit, which is then output to the circuit connected to the external interconnect electrodes. Through back-end processing, the magnitude of the external pressure can be determined by the magnitude of the detected electrical signal, thus achieving the effect of pressure detection.

[0040] Example 2

[0041] Combination Figure 7 In this embodiment, the first non-penetrating hole 11-1, the second non-penetrating hole 11-2, the third non-penetrating hole 11-3, and the fourth non-penetrating hole 11-4 are configured as four non-penetrating square holes, and the central island 14 is designed as a central inner arc island with a concave edge. Other components and connections are the same as in Embodiment 1.

[0042] Example 3

[0043] Combination Figure 8 In this embodiment, the first non-penetrating hole 11-1, the second non-penetrating hole 11-2, the third non-penetrating hole 11-3, and the fourth non-penetrating hole 11-4 are configured as four non-penetrating triangular holes, and the central island 14 is designed as a central outer arc island with its edge protruding to a certain extent. Other components and connections are the same as in Embodiment 1.

[0044] The working principle of this invention is as follows: When external pressure is applied to the pressure-transmitting silicon membrane 1, the pressure-transmitting silicon membrane 1 deforms, the protrusion 19 moves downward, squeezing the central island 14, and the central island 14 in turn drives the first elastic beam 13-1, the second elastic beam 13-2, the third elastic beam 13-3, and the fourth elastic beam 13-4 to deform simultaneously. The first graphene varistor 25-1 and the second graphene varistor 25-4, which are set between the first elastic beam 13-1, the second elastic beam 13-2, the third elastic beam 13-3, the fourth elastic beam 13-4 and the detection substrate 15, are also involved. When varistor 25-2, the third graphene varistor 25-3, and the fourth graphene varistor 25-4 are stretched, strain occurs, causing changes in the resistance values ​​of the first graphene varistor 25-1, the second graphene varistor 25-2, the third graphene varistor 25-3, and the fourth graphene varistor 25-4. This disrupts the balance of the Wheatstone bridge, generating an electrical signal in the circuit to detect external pressure. The first top protective layer 23-1, second top protective layer 23-2, third top protective layer 23-3, fourth top protective layer 23-4 and the first bottom protective layer 24-1, second bottom protective layer 24-2, third bottom protective layer 24-3, fourth bottom protective layer 24-4 above and below the graphene varistor 25-3 and the fourth graphene varistor 25-4 respectively control the first graphene varistor 25-1, the second graphene varistor 25-2, the third graphene varistor 25-3, and the fourth graphene varistor 25-4. The resistor 25-4 plays a protective role. Due to the stress concentration effect, the non-penetrating hole set between the first elastic beam 13-1, the second elastic beam 13-2, the third elastic beam 13-3, the fourth elastic beam 13-4 and the detection substrate 15 causes the graphene piezoresistor surrounding the non-penetrating hole to sense a larger strain under the same pressure, thereby improving the sensor output and sensitivity from the source. At the same time, with appropriate structural dimensions, the structural stiffness of the sensor is improved, which in turn improves the natural frequency of the sensor under the same material.

[0045] The above description only illustrates the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention, and all such changes should be included within the protection scope of the present invention.

Claims

1. A high-sensitivity, high-frequency response graphene pressure sensor, characterized in that: The package includes a housing (12), a ceramic substrate (16), a detection substrate (15), a nano-detection unit, a pressure-transmitting silicon membrane (1), a cap (17), a first elastic beam (13-1), a second elastic beam (13-2), a third elastic beam (13-3), a fourth elastic beam (13-4), a first non-penetrating hole (11-1), a second non-penetrating hole (11-2), a third non-penetrating hole (11-3), a fourth non-penetrating hole (11-4), and a welding metal (21). The housing (12) is bonded or welded to the cap (17) via the welding metal (21). The ceramic substrate (16) is installed at the bottom of the housing (12), and the detection substrate (15) is bonded to the upper part of the ceramic substrate (16). (15) A cavity is etched in the lower part to form a central island (14) and a first elastic beam (13-1), a second elastic beam (13-2), a third elastic beam (13-3), and a fourth elastic beam (13-4). The first elastic beam (13-1), the second elastic beam (13-2), the third elastic beam (13-3), and the fourth elastic beam (13-4) are all connected to the detection substrate (15). The connection between the first elastic beam (13-1), the second elastic beam (13-2), the third elastic beam (13-3), and the fourth elastic beam (13-4) and the detection substrate (15) is respectively etched with a first non-penetrating hole (11-1), a second non-penetrating hole (11-2), a third non-penetrating hole (11-3), and a fourth non-penetrating hole (11-4). The nano-detection unit is provided in four parts, which surround the first non-penetrating hole (11-1), the second non-penetrating hole (11-2), the third non-penetrating hole (11-3), and the fourth non-penetrating hole (11-4), respectively. The four nano-detection units are composed of the first nano-detection unit, the second nano-detection unit, the third nano-detection unit, and the fourth nano-detection unit. The first nano-detection unit consists of a first graphene varistor (25-1), a first top protective layer (23-1), and a first bottom protective layer (24-1), with the first graphene varistor (25-1) disposed between the first top protective layer (23-1) and the first bottom protective layer (24-1); the second nano-detection unit consists of a second graphene varistor (25-2), a second top protective layer (23-2), and a second bottom protective layer (24-2), with the second graphene varistor (25-2) disposed between the second top protective layer (23-2) and the second bottom protective layer (24-2). The third nanometer detection unit is composed of a third graphene varistor (25-3), a third top protective layer (23-3), and a third bottom protective layer (24-3), with the third graphene varistor (25-3) disposed between the third top protective layer (23-3) and the third bottom protective layer (24-3); the fourth nanometer detection unit is composed of a fourth graphene varistor (25-4), a fourth top protective layer (23-4), and a fourth bottom protective layer (24-4), with the fourth graphene varistor (25-4) disposed between the fourth top protective layer (23-4) and the fourth bottom protective layer (24-4).

2. The high-sensitivity, high-frequency response graphene pressure sensor according to claim 1, characterized in that: The detection substrate (16) is bonded to a pressure-transmitting silicon film (1) on its upper part. The pressure-transmitting silicon film (1) has cavities etched on its upper and lower parts. The lower surface of the pressure-transmitting silicon film (1) is etched to form a protrusion (19). The protrusion (19) is bonded to the central island (14) through a bonding metal (18). The pressure-transmitting silicon film (1) is bonded to the detection substrate (15) through a first metal sealing ring (2) and a second metal sealing ring (3). The lower part of the detection substrate (15) is bonded to the ceramic base (16) through a third metal sealing ring (10). The cap (17) is bonded to the packaging shell (12) through a bonding or welding connection. The cap (17) is provided with a through-hole structure (22). The through-hole structure (22) is circular or square in shape.

3. The high-sensitivity, high-frequency response graphene pressure sensor according to claim 1, characterized in that: The diagonal of the central island (14) passes through the axial midline of the upper surface of the first elastic beam (13-1), the second elastic beam (13-2), the third elastic beam (13-3), and the fourth elastic beam (13-4), respectively. The four corner points of the central island (14) are located on the axial midline of the upper surface of the first elastic beam (13-1), the second elastic beam (13-2), the third elastic beam (13-3), and the fourth elastic beam (13-4), respectively.

4. The high-sensitivity, high-frequency response graphene pressure sensor according to claim 1, characterized in that: The line connecting the geometric center point of the upper surface of the central island (14) with the geometric center points of the upper surfaces of the first non-penetrating hole (11-1), the second non-penetrating hole (11-2), the third non-penetrating hole (11-3), and the fourth non-penetrating hole (11-4) coincides with the axial centerline of the upper surfaces of the first elastic beam (13-1), the second elastic beam (13-2), the third elastic beam (13-3), and the fourth elastic beam (13-4).

5. The high-sensitivity, high-frequency response graphene pressure sensor according to claim 1, characterized in that: The first nano-detection unit is connected to the first internal interconnect electrode (4-1) and the second internal interconnect electrode (4-2) via the first internal interconnect lead (20-1) and the second internal interconnect lead (20-2). The second nano-detection unit is connected to the third internal interconnect electrode (4-3) and the fourth internal interconnect electrode (4-4) via the third internal interconnect lead (20-3) and the fourth internal interconnect lead (20-4). The third nano-detection unit is connected to the fifth internal interconnect electrode (4-5) and the sixth internal interconnect electrode (4-6) via the fifth internal interconnect lead (20-5) and the sixth internal interconnect lead (20-6). The fourth nano-detection unit is connected to the seventh internal interconnect electrode (4-7) and the eighth internal interconnect electrode (4-8) via the seventh internal interconnect lead (20-7) and the eighth internal interconnect lead (20-8).

6. The high-sensitivity, high-frequency response graphene pressure sensor according to claim 5, characterized in that: The first internal interconnect electrode (4-1) is connected to the first external interconnect lead (5-1) and the first interconnect bump (6-1); the second internal interconnect electrode (4-2) is connected to the second external interconnect lead (5-2) and the second interconnect bump (6-2); the third internal interconnect electrode (4-3) is connected to the third external interconnect lead (5-3) and the third interconnect bump (6-3); and the fourth internal interconnect electrode (4-4) is connected to the fourth external interconnect lead (5-4) and the fourth interconnect bump (6-4). The fifth internal interconnect electrode (4-5) is connected via the fifth external interconnect lead (5-5) and the fifth interconnect bump (6-5). The sixth internal interconnect electrode (4-6) is connected via the sixth external interconnect lead (5-6) and the sixth interconnect bump (6-6). The seventh internal interconnect electrode (4-7) is connected via the seventh external interconnect lead (5-7) and the seventh interconnect bump (6-7). The eighth internal interconnect electrode (4-8) is connected via the eighth external interconnect lead (5-8) and the eighth interconnect bump (6-8).

7. A high-sensitivity, high-frequency response graphene pressure sensor according to claim 6, characterized in that: The first interconnect bump (6-1) is connected to the first interconnect pad (7-1), the second interconnect bump (6-2) is connected to the second interconnect pad (7-2), the third interconnect bump (6-3) is connected to the third interconnect pad (7-3), the fourth interconnect bump (6-4) is connected to the fourth interconnect pad (7-4), the fifth interconnect bump (6-5) is connected to the fifth interconnect pad (7-5), the sixth interconnect bump (6-6) is connected to the sixth interconnect pad (7-6), the seventh interconnect bump (6-7) is connected to the seventh interconnect pad (7-7), and the eighth interconnect bump (6-8) is connected to the eighth interconnect pad (7-8).

8. A high-sensitivity, high-frequency response graphene pressure sensor according to claim 7, characterized in that: The first interconnect pad (7-1) is connected to the first external interconnect electrode (9-1) via the first lead post (8-1); the second interconnect pad (7-2) is connected to the second external interconnect electrode (9-2) via the second lead post (8-2); the third interconnect pad (7-3) is connected to the third external interconnect electrode (9-3) via the third lead post (8-3); the fourth interconnect pad (7-4) is connected to the fourth external interconnect electrode (9-4) via the fourth lead post (8-4); the fifth interconnect pad (7-5) is connected to the fifth external interconnect electrode (9-5) via the fifth lead post (8-5); and the sixth interconnect pad (7-6) is connected to the sixth external interconnect electrode via the sixth lead post (8-6). Electrode (9-6) is connected. The seventh interconnect pad (7-7) is connected to the seventh external interconnect electrode (9-7) through the seventh lead post (8-7). The eighth interconnect pad (7-8) is connected to the eighth external interconnect electrode (9-8) through the eighth lead post (8-8). The first external interconnect electrode (9-1), the second external interconnect electrode (9-2), the third external interconnect electrode (9-3), the fourth external interconnect electrode (9-4), the fifth external interconnect electrode (9-5), the sixth external interconnect electrode (9-6), the seventh external interconnect electrode (9-7), and the eighth external interconnect electrode (9-8) are all connected to external resistors. The nano-detection unit itself or together with external resistors forms a Wheatstone half-bridge or a full-bridge.

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