Packaging protection structure for nanocrystalline soft magnetic and superstructure comb-like nv color center current sensor

Abstract

The application relates to a nanocrystalline soft magnetic and superstructure comb-based NV color center current sensor packaging protection structure. A stress buffer layer is arranged to relieve cyclic thermal stress generated between different materials due to differences in thermal expansion coefficients, avoid structural cracking and delamination failure, and improve vertical heat conduction efficiency through a heat conduction through hole in the substrate, quickly dissipate high heat flux heat, and realize multi-dimensional electromagnetic shielding through a multiple physical shielding shell. The problems of thermal stress accumulation failure, insufficient heat dissipation causing measurement performance degradation, and imperfect electromagnetic shielding leading to measurement precision instability are effectively solved, and the environmental adaptability, service life, measurement precision and stability of the current sensor are improved.

Description

Technical Field

[0001] This application relates to the field of time and frequency measurement technology, and in particular to a packaging and protection structure for an NV color core current sensor based on nanocrystalline soft magnetic material and a superstructure comb-like ground. Background Technology

[0002] Wide bandgap semiconductor technology is driving the evolution of modern power systems towards higher voltage, higher frequency, and higher power density. Ultra-high voltage direct current transmission, rail transit traction, and fast charging of electric vehicles place long-term stability requirements on current sensors under extreme operating conditions. Traditional Hall effect or fluxgate detection technologies, due to core saturation, large size, and complex insulation, are no longer suitable for highly integrated power electronic equipment.

[0003] Quantum sensing technology based on diamond nitrogen-vacancy (NV) centers offers a new solution for breaking through the limitations of traditional measurements due to its atomic-level precision, natural insulation, and high magnetic sensitivity. However, when NV center quantum sensors are migrated to industrial fields, the significant differences in the coefficients of thermal expansion between diamond, silicon-based chips, and the packaging substrate cause severe transient thermal shocks inside the package when electrical equipment experiences load surges. This leads to the accumulation of cyclic thermal stress at the interface, which can easily induce fatigue cracking or delamination failure. This results in alignment deviations between the sensing element and the optical and electrical paths, ultimately causing a systematic degradation of electrical measurement performance.

[0004] Meanwhile, the fluorescence contrast and energy level stability of quantum sensing elements are extremely sensitive to operating temperature. Near the high current bus, the ambient heat and the power consumption of the integrated circuit chip combine to form a high heat flux density, which leads to phonon decoherence, deterioration of the signal-to-noise ratio and accelerated temperature drift. This reduces the measurement signal-to-noise ratio and accelerates the performance temperature drift, severely restricting the accuracy and stability of the current sensor. Summary of the Invention

[0005] Therefore, it is necessary to provide an NV color core current sensor packaging and protection structure based on nanocrystalline soft magnets and superstructure comb ground to address the above-mentioned technical problems and improve the sensing accuracy and stability of the current sensor.

[0006] In a first aspect, this application provides an NV color center current sensor packaging and protection structure based on nanocrystalline soft magnetic material and a superstructure comb-like ground. The packaging and protection structure includes a sensor layer, an integrated circuit layer, a substrate, and a heat sink stacked sequentially. The sensor layer is provided with a diamond quantum sensing module, and the integrated circuit layer is provided with a processing module. The diamond quantum sensing module acquires the magnetic field signal of the current to be measured under external laser pumping. The processing module is used to measure the magnitude of the current in the magnetic field of the current to be measured based on the magnetic field signal. The packaging and protection structure also includes:

[0007] A stress buffer layer is disposed between the integrated circuit layer and the substrate. One side surface of the stress buffer layer is adjacent to the integrated circuit layer, and the other side surface of the stress buffer layer is adjacent to the substrate.

[0008] The housing is a multi-layered physical shielding housing, with the sensor layer, integrated circuit layer, stress buffer layer, substrate and heat dissipation base all housed inside the housing;

[0009] The substrate has multiple thermally conductive vias, which are used to connect the surface of the substrate adjacent to the integrated circuit layer and the surface of the substrate away from the integrated circuit layer.

[0010] In one embodiment, the encapsulation and protection structure further includes a shielding sleeve, which at least surrounds the diamond quantum sensing module to form a closed magnetic circuit. The relative permeability of the shielding sleeve is greater than or equal to 8.8 x 10⁻⁶. 4 .

[0011] In one embodiment, the shielding sleeve is made of a nanocrystalline alloy material.

[0012] In one embodiment, a ground bus is provided in the substrate. The ground bus extends in a direction perpendicular to the stacking direction of the stress buffer layer and the substrate. The ground bus includes multiple sub-lines extending to the same side in a periodic sequence to form a comb-like structure.

[0013] In one embodiment, in the comb structure, an equivalent capacitance is formed between two adjacent sub-circuits through electric field coupling. The sub-circuits generate self-inductance through current flow, and adjacent sub-circuits generate mutual inductance through reverse current coupling. The self-inductance and mutual inductance are superimposed to form an equivalent inductance. The equivalent capacitance and equivalent inductance constitute a resonant unit, and multiple resonant units are arranged periodically to form a space frequency notch filter.

[0014] In one embodiment, the noise signal frequency band shielded by the comb structure covers 150kHz to 30MHz.

[0015] In one embodiment, the grounding busbar includes a main grounding busbar and multiple sub-circuits extending outward from the main grounding busbar, with the interval between two adjacent sub-circuits on both sides of the main grounding busbar being 0.1 mm to 1 mm.

[0016] In one embodiment, the integrated circuit layer is further provided with a temperature measurement area, a radio frequency area, a digital area and an analog sensitive area, which are arranged in separate zones within the integrated circuit layer.

[0017] In one embodiment, the integrated circuit layer is further provided with a physical isolation band, which is located between the temperature measurement area, the radio frequency area, the digital area and the analog sensitive area. The physical isolation band reduces the coupling noise between adjacent partitions through spatial isolation.

[0018] In one embodiment, the thermal conductivity of the substrate is k > 175 W / mK.

[0019] The aforementioned NV color core current sensor packaging and protection structure based on nanocrystalline soft magnets and superstructure comb-like ground alleviates cyclic thermal stress caused by differences in the coefficients of thermal expansion between different materials by setting a stress buffer layer, thus preventing structural cracking and delamination failure. The thermally conductive vias in the substrate improve the vertical heat conduction efficiency, quickly dissipating high heat flux density heat. Combined with a multi-dimensional electromagnetic shielding shell, it effectively solves the problems of easy failure due to thermal stress accumulation, measurement performance degradation caused by insufficient heat dissipation, and measurement accuracy instability caused by imperfect electromagnetic shielding in existing packaging and protection structures. This improves the environmental adaptability of the current sensor, extends its service life, and ensures measurement accuracy and stability. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a packaging and protection structure for an NV color core current sensor based on nanocrystalline soft magnetic material and superstructure comb ground in one embodiment.

[0022] Figure 2 This is a schematic diagram of the housing of a current sensor in one embodiment;

[0023] Figure 3 This is a schematic diagram of a stress buffer layer for a current sensor in one embodiment;

[0024] Figure 4 This is a schematic diagram of the structure of the shielding sleeve of a current sensor in one embodiment;

[0025] Figure 5 This is a schematic diagram of a comb-shaped structure of a current sensor in one embodiment;

[0026] Figure 6 This is a schematic diagram of the integrated circuit structure of a current sensor in one embodiment;

[0027] Figure 7 This is a schematic diagram illustrating the suppression effect of an integrated circuit for a current sensor in one embodiment. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0029] During the packaging process of quantum precision measurement devices, the mismatch in thermal expansion coefficients between the diamond quantum sensing module, silicon-based control chip, and packaging substrate induces cyclic stress at the interface under thermal shock conditions, leading to fatigue cracking or delamination failure. Simultaneously, under high power density conditions, the combined effect of ambient heat and integrated circuit layer power consumption raises the temperature of the quantum sensing element, causing phonon decoherence and resulting in a decrease in the measurement signal-to-noise ratio. Furthermore, in complex electromagnetic field environments, existing shielding schemes cannot effectively isolate broadband electromagnetic interference, causing phase-locked loss or accuracy instability in the signal chain.

[0030] For example, during the operation of a converter station in an ultra-high voltage direct current transmission system, when a high-current bus experiences a load surge, the transient thermal shock accumulates stress at the interface between the diamond quantum sensing module and the silicon-based control chip, causing optical path alignment deviation. At the same time, the strong electrostatic field generated on the high-voltage side and the frequency conversion switching noise interfere with the magnetic field signal acquisition, causing the current measurement results to drift.

[0031] If the above problems are not solved, the reliability of the encapsulation and protection structure will be reduced, the long-term operating accuracy of the quantum sensor cannot be maintained, and the measurement system will frequently fail in the industrial field, hindering the practical application of quantum sensing technology in the health monitoring of high-energy-efficiency power electronic equipment.

[0032] Based on this, in an exemplary embodiment, such as Figure 1 As shown, an NV color core current sensor packaging and protection structure 100 based on nanocrystalline soft magnetic material and a superstructure comb ground is provided, serving as the overall physical framework for protecting and integrating the core components of the current sensor. Its main function is to provide mechanical support, environmental isolation, and electromagnetic shielding for the internal sensitive element, ensuring that the sensor can operate stably and reliably under various operating conditions and accurately measure current.

[0033] The encapsulation protection structure 100 includes a sensor layer 10, an integrated circuit layer 20, a substrate 30, and a heat dissipation base 40 stacked in sequence. The sensor layer 10 is provided with a diamond quantum sensing module 11, and the integrated circuit layer 20 is provided with a processing module 21. The diamond quantum sensing module 11 acquires the magnetic field signal of the magnetic field of the current to be measured under external laser pumping, and the processing module 21 is used to measure the magnitude of the magnetic field of the current to be measured based on the magnetic field signal.

[0034] The sensor layer 10 can be a functional area in the encapsulation and protection structure 100, used to support and position the diamond quantum sensing module 11. The sensor layer 10 usually needs to have good optical transparency or specific physical properties to support the operation of the diamond quantum sensing module 11.

[0035] The diamond quantum sensing module 11 can be the core sensing element of a current sensor, utilizing nitrogen-vacancy (NV) color centers in diamond as quantum probes. Through external laser pumping, the NV color centers can sense the magnetic field signal generated by the current to be measured and convert it into a detectable optical signal, thereby achieving precise measurement of the magnetic field.

[0036] The integrated circuit layer 20 may be a region in the encapsulation protection structure 100 used for integrating electronic control and signal processing circuits, and may include integrated circuit chips for driving the diamond quantum sensing module 11, acquiring the output signal of the diamond quantum sensing module 11, performing signal amplification, filtering, analog-to-digital conversion and data processing.

[0037] The processing module 21 can be a functional unit on the integrated circuit layer 20, responsible for processing the magnetic field signal acquired by the diamond quantum sensing module 11. Through specific algorithms and circuits, the processing module 21 can convert the magnetic field signal into the corresponding current magnitude and output the measurement result.

[0038] Specifically, the encapsulation and protection structure 100 can be constructed using various layering methods. For example, the layers can be fixed using traditional adhesives, or interlayer connections can be achieved through processes such as welding or co-sintering. In one implementation, the sensor layer 10, integrated circuit layer 20, substrate 30, and heat sink 40 can be bonded together using epoxy resin or silicone adhesive to form a single integrated structure. The diamond quantum sensing module 11 can be mounted on the sensor layer 10 using flip-chip technology or wire bonding technology.

[0039] The processing module 21 can be a custom application-specific integrated circuit (ASIC) or a programmable logic device (FPGA), mounted on the integrated circuit layer 20 using surface mount technology (SMT). The diamond quantum sensing module 11 can emit a laser beam from an external laser, which is guided through an optical path to the diamond quantum sensing module 11 to excite its internal NV color centers, thereby sensing the magnetic field signal. After receiving the electrical signal output from the diamond quantum sensing module 11, the processing module 21 can use a digital signal processor (DSP) to execute a magnetic field-to-current conversion algorithm to determine the magnitude of the current to be measured.

[0040] In an exemplary embodiment, the encapsulation protection structure 100 further includes a stress buffer layer 50, which is disposed between the integrated circuit layer 20 and the substrate 30. One side surface of the stress buffer layer 50 is adjacent to the integrated circuit layer 20, and the other side surface of the stress buffer layer 50 is adjacent to the substrate 30.

[0041] The stress buffer layer 50 can be a material layer with a certain degree of elasticity and flexibility, disposed between different material layers, to absorb and disperse mechanical stress caused by the mismatch of the coefficients of thermal expansion (CTE) of the materials. The stress buffer layer 50 can effectively alleviate the thermal stress concentration inside the package, prevent structural cracking or delamination, thereby improving the reliability and lifespan of the package.

[0042] Here, the stress buffer layer 50 can be made of polymer materials, such as polyimide film or silicone rubber gasket.

[0043] In one implementation, the stress buffer layer 50 can be pre-cut into a shape that matches the dimensions of the integrated circuit layer 20 and the substrate 30, and then fixed between the integrated circuit layer 20 and the substrate 30 by hot pressing or bonding. The stress buffer layer 50 can absorb the mechanical stress caused by the difference in the coefficients of thermal expansion of the materials of the integrated circuit layer 20 and the substrate 30, thereby reducing stress concentration at the interface.

[0044] The housing 101 is a multi-layered physical shielding housing 101. The sensor layer 10, integrated circuit layer 20, stress buffer layer 50, substrate 30 and heat dissipation base 40 are all disposed inside the housing 101.

[0045] In addition, please refer to Figure 2 , Figure 2 This is a schematic diagram of one structure of the housing 101. The encapsulation protection structure 100 also includes the housing 101, which serves as the outermost layer of protection, completely enclosing all internal functional layers and modules, including the diamond NV color center sensor, AFE (analog front-end), DSP (digital signal processing core), TMU (on-chip temperature monitoring and compensation module), and RFU (reconfigurable microblogging synthesis module). The housing 101 not only provides mechanical protection but also possesses multiple physical shielding functions to isolate electromagnetic interference, electrostatic fields, and other physical influences from the external environment.

[0046] It should be noted that the housing 101 is a multi-physical shielding housing 101, capable of providing shielding for multiple physical effects simultaneously. For example, the housing 101 can integrate electromagnetic shielding, electrostatic shielding, magnetic shielding, and other functions to cope with complex and ever-changing external interference environments and ensure the signal integrity of internal sensitive components.

[0047] As an example, the housing 101 can be made of a composite of multiple materials to achieve multiple physical shielding functions. For example, the housing 101 can be made of a composite of a metal alloy (such as an aluminum alloy or a copper alloy) and a conductive polymer material, or the metal housing 101 can be lined with a wave-absorbing material. In one implementation, the housing 101 can adopt a two-piece or multi-piece structure, with the parts connected by screws, clips, or welding to form a sealed cavity that completely encloses all internal components.

[0048] The substrate 30 has multiple thermally conductive vias, which are used to connect one side surface adjacent to the integrated circuit layer 20 and the other side surface away from the integrated circuit layer.

[0049] Thermal vias can be channels that run through the interior of the substrate 30. They are usually filled with a material with high thermal conductivity. The main function of thermal vias is to provide an efficient vertical heat conduction path to quickly transfer the heat generated by the integrated circuit layer 20 to the heat sink 40 or other heat dissipation structures, thereby reducing the local temperature and maintaining the stable operating temperature of the internal components.

[0050] As an example, the thermally conductive vias can be formed by drilling and then filling them with a thermally conductive material. For instance, multiple holes can be formed on the substrate 30 by mechanical drilling or laser drilling, and then these holes can be filled with a high thermal conductivity epoxy resin or metal (such as copper) paste, and a thermally conductive path can be formed by sintering or curing. The thermally conductive vias can be arranged in a uniform distribution to ensure that heat can be efficiently transferred from the integrated circuit layer 20 to the other side of the substrate 30, and then to the heat sink 40.

[0051] In one exemplary embodiment, the thermal conductivity of substrate 30 is k > 175 W / mK.

[0052] It should be noted that in this embodiment, in the three-dimensional stacked heat dissipation architecture based on the substrate 30 in the above-mentioned packaging protection structure 100, aluminum nitride (AlN) ceramic is used as the substrate 30, and the diamond quantum sensing module 11 and the processing module 21 (ASIC chip) are vertically interconnected, and the vertical heat conduction hole realizes the conduction of heat flux density (q).

[0053] Here, the heat flux density q is transferred within the package according to Fourier's law of thermal conductivity:

[0054]

[0055] Where -k is the dimensionless thermal conductivity of the material, Tjunction is the actual operating temperature inside the chip, and Tcase is the temperature of the chip package surface. An array of vertical thermal vias (VIA) is implanted inside the substrate, which greatly reduces the heat conduction distance d. The chip junction temperature Tjunction of the processing module 21 (ASIC chip) reaches equilibrium in a very short time, avoiding quantum state collapse caused by phonon coupling.

[0056] The following example will provide a more detailed explanation of the above technical solution:

[0057] In a current monitoring scenario within a high-voltage direct current (HVDC) transmission system, non-invasive detection of high-power bus current is required. The main technical challenges in this scenario include: First, significant differences in the coefficients of thermal expansion exist between the diamond quantum sensing module 11, the silicon-based integrated circuit chip, and the packaging substrate. During power equipment operation, frequent load surges can cause severe transient thermal shocks within the packaging, easily inducing fatigue cracking or delamination failure at the packaging interface, leading to systemic performance degradation. Second, the combined effect of ambient heat near the high-current bus and the power consumption of the integrated circuit chip itself can decrease the quantum state stability of the diamond quantum sensing module 11, reducing the measurement signal-to-noise ratio. Furthermore, the strong electrostatic field generated on the high-voltage side, the broadband electromagnetic interference noise generated by frequency conversion switching, and stray magnetic fields create an extremely harsh electromagnetic background, easily leading to signal chain phase-locking loss or measurement instability.

[0058] To address the aforementioned issues, the NV color center current sensor packaging and protection structure 100 based on nanocrystalline soft magnetic material and a superstructure comb-like ground provided in this embodiment is applied to this current monitoring scenario. Specifically, the packaging and protection structure 100 sequentially stacks a sensor layer 10, an integrated circuit layer 20, a substrate 30, and a heat sink 40. A diamond quantum sensing module 11 mounted on the sensor layer 10 acquires the magnetic field signal of the current to be measured through external laser pumping. The processing module 21 on the integrated circuit layer 20 measures the current magnitude based on this magnetic field signal.

[0059] To address the physical mismatch between materials, the encapsulation protection structure 100 incorporates a stress buffer layer 50 between the integrated circuit layer 20 and the substrate 30. For example, this stress buffer layer 50 can be made of a polymer material with high flexibility and a moderate coefficient of thermal expansion. When the system experiences transient thermal shock due to load changes, the integrated circuit layer 20 and the substrate 30 will tend to shift relative to each other due to the difference in their coefficients of thermal expansion. In this case, the stress buffer layer 50 can effectively absorb and disperse these mechanical stresses, preventing stress concentration at the interface, thereby significantly reducing the risk of fatigue cracking or delamination failure. This ensures the alignment accuracy of the diamond quantum sensing module 11 with the optical path and circuitry, maintaining the long-term performance stability of the system.

[0060] Please refer to Figure 3 , Figure 3 This is an exemplary structural diagram of the stress buffer layer 50 in this embodiment. To address the mismatch in thermal expansion coefficients between different materials, this embodiment performs simulation optimization for packaging reliability. Without the buffer layer, the chip is in direct contact with the substrate 30, resulting in high stress at stress concentration points. By adding a polyimide buffer layer as the stress buffer layer 50 between the chip and the substrate 30, the stress buffer layer 50 can effectively absorb and disperse these mechanical stresses, preventing stress concentration at the interface and achieving low stress at stress concentration points.

[0061] In practical applications, when the temperature changes by ΔT, the thermal stress σ generated at the interface can be expressed by the following formula, specifically: .

[0062] Where E is the elastic modulus. The thermal stress generated at the interface can be calculated by calculating the product of the elastic modulus, the difference in the thermal expansion coefficients of the two materials, and the temperature change.

[0063] In this embodiment, by introducing a polyimide stress buffer layer 50 between the integrated circuit layer 20 and the substrate 30, the interfacial shear stress is effectively released, preventing the risk of delamination during long-term service.

[0064] To address the challenges of thermal management under high power density, the substrate 30 is provided with multiple thermally conductive vias that penetrate the substrate 30, connecting the surface adjacent to the integrated circuit layer 20 and the surface away from the integrated circuit layer. For example, these thermally conductive vias can be filled with copper material with high thermal conductivity. When the integrated circuit layer 20 generates a large amount of heat during operation, and when external ambient heat is introduced, these thermally conductive vias provide an efficient vertical heat conduction path, rapidly conducting heat from the integrated circuit layer 20 to the heat sink 40 below. Thus, the heat sink 40 can further dissipate heat into the environment, effectively reducing the operating temperature of the diamond quantum sensing module 11, suppressing its phonon decoherence effect, ensuring the stability of the quantum state, thereby improving the measurement signal-to-noise ratio and reducing performance temperature drift.

[0065] Furthermore, to address the interference of complex electromagnetic field environments on signal integrity, the encapsulation protection structure 100 employs a multi-layered physical shielding shell 101 to enclose all internal components. For example, the shell 101 can be constructed from multiple layers of composite materials, including a conductive metal layer for electromagnetic shielding and a dielectric layer for electrostatic shielding. This multi-layered physical shielding shell 101 effectively intercepts strong electrostatic fields generated on the high-voltage side, broadband electromagnetic interference noise generated by frequency switching, and stray magnetic fields from the environment. Through this comprehensive shielding design, the magnetic field signal acquired by the diamond quantum sensing module 11 maintains its integrity during transmission and processing, avoiding phase-locked loss or measurement instability caused by external interference, and ensuring the accuracy and reliability of current measurement.

[0066] Based on the above examples, compared with the prior art solutions of direct bonding between materials or using a single adhesive, the encapsulation protection structure 100 of this embodiment introduces a stress buffer layer 50, which provides a flexible material between the integrated circuit layer 20 and the substrate 30. This effectively absorbs and disperses the mechanical stress caused by the difference in thermal expansion coefficients, improves the reliability of the encapsulation protection structure 100 under frequent thermal shocks, and avoids the common interface cracking or delamination failure problems in traditional solutions, thereby ensuring the long-term alignment accuracy of sensitive components with optical paths and circuits.

[0067] In terms of thermal management, existing technologies mostly employ traditional passive heat dissipation or simple heat conduction designs, which are difficult to rapidly dissipate heat at high power densities. This embodiment constructs an efficient vertical heat conduction channel by creating multiple thermally conductive vias in the substrate 30, connecting one surface adjacent to the integrated circuit layer 20 and the other surface away from the integrated circuit layer. This design allows the heat generated by the integrated circuit layer 20 to be rapidly dissipated, effectively reducing the operating temperature of the diamond quantum sensing module 11, thereby maintaining the stability of its quantum state, improving the measurement signal-to-noise ratio, and reducing performance temperature drift, thus solving the problem of temperature-dependent quantum state stability in existing technologies.

[0068] To address interference from complex electromagnetic environments, this embodiment employs a multi-layered physical shielding housing 101, which simultaneously provides electromagnetic shielding, electrostatic shielding, and other physical shielding functions. The housing 101 completely encloses all core components, including the sensor layer 10, integrated circuit layer 20, stress buffer layer 50, substrate 30, and heat dissipation base 40, forming an isolated internal environment. This comprehensive shielding solution effectively intercepts strong electrostatic fields, broadband electromagnetic interference noise, and stray magnetic fields from the environment, ensuring the integrity of the signal chain. It avoids the limitations of traditional single-shielding solutions that may compromise certain aspects, significantly improving the measurement accuracy and stability of the current sensor in complex electromagnetic environments.

[0069] Based on the above technical solution, the encapsulation and protection structure 100 of this embodiment comprehensively improves the environmental adaptability, operational reliability and measurement accuracy of the quantum current sensor through the synergistic effect of the stress buffer layer 50, the thermally conductive through hole and the multiple physical shielding shell 101.

[0070] In some of the above embodiments, the NV color core current sensor encapsulation and protection structure 100 based on nanocrystalline soft magnetic material and a superstructure comb-like ground acquires the magnetic field signal of the current to be measured through a diamond quantum sensing module 11 under external laser pumping, and the processing module 21 measures the current magnitude based on the magnetic field signal. However, in practical applications, the magnetic field signal acquired by the diamond quantum sensing module 11 is easily affected by external stray magnetic fields, thus affecting the measurement accuracy and stability.

[0071] Based on this, in an exemplary embodiment, such as Figure 4 As shown, an NV color core current sensor encapsulation and protection structure 100 based on nanocrystalline soft magnetic material and a superstructure comb-like ground is provided. This encapsulation and protection structure 100 further includes a shielding sleeve 102, which at least surrounds the diamond quantum sensing module 11 to form a closed magnetic circuit. The relative permeability of the shielding sleeve 102 is greater than or equal to 8.8 x 10⁻⁶. 4 .

[0072] Here, the shielding sleeve 102 serves as a structure for blocking or guiding magnetic fields to protect internal sensitive components from interference from external magnetic fields.

[0073] As one implementation, the shielding sleeve 102 can be a ring-shaped, cylindrical, or box-shaped structure made of high magnetic permeability material to completely or partially enclose the diamond quantum sensing module 11; as another implementation, the shielding sleeve 102 can also be a multi-layer magnetic shielding structure, which can achieve wider bandwidth or higher intensity magnetic field shielding by combining materials with different magnetic permeability.

[0074] The shielding sleeve 102 can be a hollow cylinder or cuboid, with the diamond quantum sensing module 11 placed inside it; or, the shielding sleeve 102 can also be a U-shaped or C-shaped structure, surrounding the diamond quantum sensing module 11 from multiple directions, but leaving some openings for laser pumping or signal output to form a closed magnetic circuit.

[0075] Here, a closed magnetic circuit can form a continuous loop of magnetic field lines inside the magnetic material. Based on this loop, the environmental interference magnetic field Benv can be guided out of the NV color center sensitive region, thereby reducing the influence of the environmental stray magnetic field Benv on the resonant frequency f+- used to reflect the intensity of the magnetic field Bsig of the current under test, or confining the magnetic field Bsig of the current under test inside the shielding material to prevent it from leaking outward and being interfered with by the high-frequency interference magnetic field Bnoise.

[0076] It should be noted that since Benv and Bnoise originate from the external space and are incident from the outside of the shielding sleeve 102, they are bypassed by the low magnetic resistance material of the shielding sleeve 102 wall and do not enter the internal cavity; Bsig is the current-measuring magnetic field in the bus current, located at the opening end of the shielding sleeve 102 or a specific coupling position, entering from the designed inlet of the shielding sleeve 102, and being converged and guided by the sleeve to pass through the diamond center.

[0077] In one embodiment, the relative permeability of the shielding sleeve 102 is greater than or equal to 8.8 x 10^4, where relative permeability is the ratio of the material's permeability to the permeability of free space, and is an important parameter for measuring the material's magnetic permeability. High relative permeability means that the material can guide magnetic field lines more effectively.

[0078] In one exemplary embodiment, the shielding sleeve 102 is made of a nanocrystalline alloy material.

[0079] Here, by selecting nanocrystalline soft magnetic materials to fabricate the shielding sleeve 102, its relative permeability can be greatly improved. The shielding effectiveness of the shielding sleeve 102 against low-frequency environmental interference magnetic fields can be calculated by the following formula:

[0080]

[0081] Where t is the thickness of the shielding layer, r is the inner diameter, and μ r The permeability is given by the fact that nanocrystalline materials have extremely high magnetic flux attraction capabilities, which can guide the current-measuring magnetic field Bsig along a specific low magnetic resistance path into the diamond center, significantly enhancing the signal gain.

[0082] Furthermore, based on the shielding sleeve 102, it can shield the ambient stray magnetic field Benv and the high-frequency interference magnetic field Bnoise, and detect the intensity of the magnetic field Bsig of the current under test. Here, the intensity of the magnetic field Bsig of the current under test can be calculated by detecting the change in the resonant frequency f+-, and the calculation formula is as follows:

[0083]

[0084] Where D(T) is the zero-field splitting constant, γe is the electron gyromagnetic ratio, Benv is the ambient stray magnetic field, and Bnoise is the high-frequency interference magnetic field. In this embodiment, the packaging goal is to maximize the transmission efficiency of Bsig through the physical architecture while eliminating the influence of Benv and Bnoise.

[0085] In the above embodiment, a shielding sleeve 102 made of a material with a relative permeability greater than or equal to 8.8 x 10^4 is introduced into the NV color center current sensor encapsulation protection structure 100 based on nanocrystalline soft magnetic and superstructure comb ground, and is at least enclosed within the diamond quantum sensing module 11, thereby forming a closed magnetic circuit. When a stray magnetic field exists externally, due to the high permeability of the shielding sleeve 102 material, the magnetic field lines will preferentially pass along the internal path of the shielding sleeve 102 material, rather than penetrating into the diamond quantum sensing module 11 region inside the shielding sleeve 102. By forming a closed magnetic circuit, the shielding sleeve 102 can effectively guide and confine the external magnetic field within itself, thereby significantly attenuating the magnetic field strength of the environment in which the diamond quantum sensing module 11 is located. This allows the diamond quantum sensing module 11 to accurately sense the magnetic field of the current to be measured and transmit the precise magnetic field signal to the processing module 21 for current magnitude measurement.

[0086] In some of the above embodiments, this application proposes an NV color core current sensor packaging and protection structure 100 based on nanocrystalline soft magnetism and superstructure comb ground. The structure consists of a sensor layer 10, an integrated circuit layer 20, a substrate 30 and a heat dissipation base 40 stacked in sequence, supplemented by a stress buffer layer 50 and a multi-layer physical shielding shell 101. The structure aims to provide a stable working environment for the diamond quantum sensing module 11 and the processing module 21.

[0087] However, in practical applications, electromagnetic noise generated by power supply, signal lines or other circuit components may exist inside the substrate 30. This noise may propagate inside the substrate 30 through conduction or coupling, thereby interfering with the purity of the magnetic field signal acquired by the diamond quantum sensing module 11 and the accuracy of the current measurement by the processing module 21. Especially in scenarios where high measurement accuracy is required, the broadband electromagnetic pulse generated by the ultra-high voltage switch becomes a key technical problem for the current sensor to perform accurate measurement.

[0088] In one exemplary embodiment, such as Figure 5 As shown, an NV color core current sensor packaging and protection structure 100 based on nanocrystalline soft magnetic material and superstructure comb-shaped ground is provided. A ground bus is provided in the substrate 30 of the packaging and protection structure 100. The ground bus extends in a direction perpendicular to the stacking direction of the stress buffer layer 50 and the substrate 30. The ground bus includes multiple sub-lines extending to the same side in a direction parallel to the stacking direction. The multiple sub-lines are arranged in a periodic sequence to form a comb-shaped structure 103.

[0089] The grounding bus is a conductive path used to provide a common reference potential and guide noise current. It can provide a stable potential reference point for sensitive circuits inside the encapsulation protection structure 100 and effectively guide any electromagnetic noise or stray currents that may be generated to the ground or common reference point, thereby reducing the impact of noise on circuit performance.

[0090] As an example, the grounding busbar can be designed as a specific metal layer or metal trace inside the substrate 30. For example, a copper foil layer can be used as the grounding busbar, or a specific grounding network can be formed by etching inside the substrate 30.

[0091] It should be noted that the grounding bus extends perpendicular to the stacking direction of the stress buffer layer 50 and the substrate 30, and can be laid out along the planar direction of the substrate 30 (e.g., the XY plane). This allows the grounding bus to effectively cover a specific area inside the substrate 30, providing a uniform ground reference for the circuits within that area, and facilitating integration with other circuit layers inside the substrate 30. For example, it can serve as an independent conductive layer inside the substrate 30, or as a specific trace layout for a layer in a multilayer substrate 30.

[0092] Furthermore, multiple sub-circuits are arranged periodically to form a comb-like structure 103. This periodically arranged comb-like structure 103 possesses unique response characteristics in electromagnetics, enabling it to suppress electromagnetic waves or noise signals within a specific frequency range. This allows for notch filtering or filtering of noise at specific frequencies, thereby improving the anti-interference capability of the internal circuitry of the encapsulation protection structure 100. For example, this comb-like structure 103 can be designed as a planar electromagnetic bandgap structure to suppress the propagation of electromagnetic noise in a specific frequency band.

[0093] In an exemplary embodiment, in the comb structure 103, an equivalent capacitance is formed between two adjacent sub-circuits through electric field coupling. The sub-circuits generate self-inductance through current flow, and adjacent sub-circuits generate mutual inductance through reverse current coupling. The self-inductance and mutual inductance are superimposed to form an equivalent inductance. The equivalent capacitance and equivalent inductance constitute a resonant unit, and multiple resonant units are arranged periodically to form a space frequency notch filter.

[0094] Between adjacent conductors, charge induction occurs due to uneven charge distribution or potential difference, resulting from the interaction of electric fields. In the sub-circuits of the comb structure 103, there is a certain spacing between adjacent sub-circuits. When a high-frequency signal passes through these sub-circuits, an electric field can be formed between two adjacent sub-circuits, causing the charge to redistribute on the surface of the sub-circuit, thereby generating an equivalent capacitance.

[0095] Here, the equivalent capacitance can be considered as the capacitance between two parallel conductor plates, and its size is related to the geometry of the sub-circuit, the spacing, and the dielectric constant of the medium.

[0096] Equivalent capacitance is typically used in circuits for storing charge, filtering, or as part of a resonant circuit. The size of the equivalent capacitance can be precisely controlled by adjusting the width and spacing of the sub-line and the dielectric constant of the substrate 30 material. For example, decreasing the sub-line spacing or increasing the width of the sub-line increases the equivalent capacitance; using a substrate 30 material with a high dielectric constant achieves the same effect.

[0097] Furthermore, when current flows through a conductor, an induced electromotive force is generated due to the change in current. In the sub-circuit, the current flow generates a magnetic field. When the current changes, the magnetic field also changes, thus generating an induced electromotive force in the sub-circuit that opposes the change in current, i.e., self-induction.

[0098] The magnitude of self-inductance is related to the length, cross-sectional area, shape of the sub-circuit, and the surrounding permeability. Self-inductance is commonly used in circuits to limit the rate of change of current, store energy, or serve as part of a resonant circuit. The magnitude of self-inductance can be adjusted by changing the length, width, and thickness of the sub-circuit, or by using a spiral, serpentine, or other similar layout. For example, increasing the length of the sub-circuit or decreasing its width can increase the self-inductance.

[0099] Furthermore, there is the phenomenon of induced electromotive force (EMF) being generated in another adjacent circuit. In the comb structure 103, when the currents in adjacent sub-circuits are in opposite directions (i.e., reverse currents), the magnetic fields they generate interact, causing induced EMFs to be generated in each other's circuits. This phenomenon is called reverse current coupling mutual inductance. The mutual inductance effect affects the overall impedance characteristics of the sub-circuits.

[0100] The magnitude of mutual inductance is related to the spacing, length, relative position, and current direction of adjacent sub-circuits. The magnitude of mutual inductance can be controlled by optimizing the sub-circuit layout, such as adjusting the spacing and relative length. Self-inductance and mutual inductance are superimposed to form an equivalent inductance. In a multi-conductor system, each conductor not only has its own self-inductance but also generates mutual inductance with adjacent conductors.

[0101] When multiple sub-circuits are arranged in a specific manner and carry current, their total inductive effect is the superposition of self-inductance and mutual inductance. This superposition effect forms the equivalent inductance of the entire comb structure 103. The equivalent inductance can be used to measure the resistance of the entire structure to changes in current.

[0102] The magnitude of the equivalent inductance can be controlled by precisely designing the geometric parameters (such as length, width, and spacing) and arrangement of the sub-circuits. For example, by adjusting the periodic arrangement of the sub-circuits, the superposition effect of self-inductance and mutual inductance can be optimized.

[0103] Furthermore, a resonant unit is a circuit composed of inductors and capacitors. When its operating frequency matches its resonant frequency, resonance occurs. At the resonant frequency, the impedance characteristics of the circuit change significantly; for example, the impedance is minimum at series resonance and maximum at parallel resonance. Therefore, multiple resonant units arranged periodically form a space frequency notch filter to suppress noise within a specific frequency range.

[0104] Specifically, a space frequency notch filter utilizes periodically arranged resonant elements to generate high or low impedance at a specific frequency, thereby attenuating or blocking signals at that frequency. When multiple resonant elements are arranged periodically, the interaction between them forms a structure with band-stop characteristics, i.e., a space frequency notch filter, to effectively filter out electromagnetic noise in a specific frequency band.

[0105] In one exemplary embodiment, the noise signal frequency band shielded by the comb structure 103 covers 150 kHz to 30 MHz.

[0106] In the above embodiments, by designing the grounding busbar in the substrate 30 as a comb-shaped structure 103 with specific electromagnetic characteristics, effective suppression of noise signals is achieved.

[0107] Specifically, in the comb structure 103, adjacent sub-circuits form distributed equivalent capacitances due to the interaction of electric fields. Simultaneously, when current flows through a sub-circuit, a self-inductance effect is generated; and between adjacent sub-circuits, especially when reverse current coupling exists, a mutual inductance effect is also generated. Through the superposition of self-inductance and mutual inductance, they collectively constitute the equivalent inductance of the entire comb structure 103. The distributed equivalent capacitance and equivalent inductance are physically tightly combined, naturally forming multiple LC resonant units.

[0108] When the resonant units are arranged periodically, as a whole, they exhibit high impedance characteristics within a specific frequency range, thus forming a space frequency notch filter. This filter can specifically attenuate or block noise signals of a specific frequency, preventing them from propagating along the ground bus and coupling into sensitive circuits within the encapsulation protection structure 100. In this way, the comb structure 103, which originally only served as a grounding path, is given an active filtering function, effectively improving the high-frequency noise suppression capability of the encapsulation protection structure 100 without introducing additional discrete components.

[0109] In one exemplary embodiment, the grounding busbar includes a main grounding busbar and multiple sub-circuits extending outward from the main grounding busbar, with the interval between two adjacent sub-circuits on both sides of the main grounding busbar being 0.1 mm to 1 mm.

[0110] The main grounding busbar, as the core of the comb-like structure 103, can be a relatively wide conductive trace inside the substrate 30, or a locally thickened conductive area, typically made of highly conductive materials such as copper or silver to minimize resistance loss. Multiple sub-circuits extend outward from the main grounding busbar; these sub-circuits can extend perpendicular to the main grounding busbar, or they can follow inclined or curved paths.

[0111] The spacing between two adjacent sub-circuits on both sides of the main grounding busbar is 0.1mm to 1mm, which affects the electric field coupling and magnetic field coupling strength between the sub-circuits. This, in turn, determines the equivalent capacitance and equivalent inductance of the comb structure 103 as a spatial frequency notch filter, enabling the comb structure 103 to resonate within the target noise frequency range, thereby achieving efficient noise suppression.

[0112] As a concrete example, the comb-like structure 103 described above can be implemented using copper traces within a multilayer substrate 30. For instance, multiple parallel sub-lines can be etched into an inner layer of the substrate 30, extending outward from the main ground busbar to form a comb-like shape. To enable the comb-like structure 103 to effectively shield noise signals from 150kHz to 30MHz, the width of the sub-lines can be designed to be 0.2 mm, the spacing between adjacent sub-lines can be set to 0.5 mm, and the effective length of the sub-lines can be 10 mm. The substrate 30 material can be FR-4, a material with a relatively stable dielectric constant and low loss. Through this specific geometric dimension and material selection, the distributed inductor and capacitor network formed by the comb-like structure 103 is precisely tuned to exhibit significant attenuation characteristics in the frequency range of 150kHz to 30MHz, thereby effectively filtering out or reflecting electromagnetic noise in this frequency band.

[0113] In the above embodiments, the comb structure 103 is mainly used to suppress broadband electromagnetic pulses. The comb structure 103 utilizes the equivalent inductance Leq and equivalent capacitance Ceq generated by the periodically arranged miniature comb grid to construct a spatial frequency notch filter. The calculation formula for the center suppression frequency f0 of this spatial frequency notch filter is as follows:

[0114]

[0115] Based on this, the comb structure 103 enables f0 to cover the EMI noise band from 150kHz to 30MHz, and the ground plane exhibits extremely high surface impedance Zcomb, blocking the propagation of common-mode current in the signal chain.

[0116] In one exemplary embodiment, such as Figure 6As shown, an NV color core current sensor packaging and protection structure 100 based on nanocrystalline soft magnetic material and superstructure comb ground is provided. In the integrated circuit layer 20 of the packaging and protection structure 100, a temperature measuring area, a radio frequency area, a digital area and an analog sensitive area are also provided. The temperature measuring area, radio frequency area, digital area and analog sensitive area are arranged in sections within the integrated circuit layer 20.

[0117] The temperature measurement area refers to a region on the integrated circuit layer 20 specifically designed for integrating temperature sensing elements and related circuitry. The main function of this area is to monitor the temperature of the integrated circuit layer 20 or the diamond quantum sensing module 11, providing necessary temperature compensation data for the system or implementing overheat protection.

[0118] The temperature measurement area can integrate various types of temperature sensors. For example, it can use on-chip temperature sensors, or achieve accurate temperature measurement by integrating thermistors, thermocouples, or PN junction temperature sensors.

[0119] The radio frequency (RF) region can refer to a dedicated area on the integrated circuit layer 20 for processing high-frequency signals, such as for RF excitation or signal readout of the diamond quantum sensing module 11. This region is designed to ensure the integrity of RF signals, reduce high-frequency noise interference to other areas, and effectively prevent external RF interference from entering.

[0120] The radio frequency (RF) area can include components such as RF oscillators, RF amplifiers, mixers, and filters. Its design can employ transmission line structures such as microstrip lines and coplanar waveguides, combined with RF isolation technologies, such as guard rings or ground plane partitioning, to optimize performance.

[0121] The digital area can refer to a region on integrated circuit layer 20 specifically used for processing digital logic signals and data transmission. The main function of this area is to centralize digital circuitry to reduce interference from digital switching noise on analog signals and optimize the transmission path of digital signals.

[0122] The digital area can contain microcontrollers, digital signal processors, memory, logic gate arrays, etc. Its implementation can use independent digital power domains and ground planes, and utilize decoupling capacitors and filtering circuits to effectively suppress digital noise.

[0123] The analog sensitive area can refer to a region on the integrated circuit layer 20 specifically designed for processing weak analog signals, such as the magnetic field signal output by the diamond quantum sensing module 11. This region is intended to protect the analog signal from digital noise, radio frequency interference, and power supply noise, ensuring signal purity and measurement accuracy.

[0124] The analog sensitive area can include low-noise amplifiers, analog-to-digital converters, analog filters, reference voltage sources, etc. It can be implemented by using independent analog power domains and ground planes, and by using shielding, guard rings, differential signal transmission and other technologies to improve anti-interference capabilities.

[0125] Partitioned layout can physically divide and isolate different functional modules on integrated circuit layer 20, namely temperature measurement area, radio frequency area, digital area and analog sensitive area. This layout method, through physical isolation and optimized layout, minimizes electromagnetic interference and thermal interference between different functional modules, thereby improving the performance and reliability of the entire system.

[0126] Zonal layout can be achieved by planning independent physical regions on the integrated circuit layer 20, using techniques such as ground plane partitioning, power plane partitioning, guard rings, or isolation trenches. For example, based on the different noise sensitivities of each region, sensitive regions can be kept at sufficient physical distance from noise source regions, and independent power and ground lines can be used.

[0127] In an exemplary embodiment, the integrated circuit layer 20 is further provided with a physical isolation band, which is located between the temperature measurement area, the radio frequency area, the digital area and the analog sensitive area. The physical isolation band reduces the coupling noise between adjacent partitions through spatial isolation.

[0128] A physical isolation strip refers to a structural element on the integrated circuit layer 20 used to separate different functional areas. Its core function is to provide a physical barrier to reduce or block unnecessary energy or signal transmission between different areas.

[0129] Physical isolation strips can take various forms. For example, they can be deep trench structures formed by etching processes in the integrated circuit layer 20, which can be filled with insulating material to enhance the isolation effect; or they can be grounding protection rings set around sensitive areas to absorb and dissipate potential coupling noise by providing a low impedance path.

[0130] Spatial isolation refers to reducing or eliminating the mutual interference between different circuits or functional areas by creating distances or setting physical barriers in a physical dimension. In integrated circuit design, common methods for achieving spatial isolation include optimizing the layout to ensure sufficient physical spacing between functional areas, or by setting physical isolation bands to forcibly introduce high impedance or attenuation into signal coupling paths, thereby achieving effective area separation at the physical level. Reducing coupling noise between adjacent zones refers to the phenomenon where energy or signals from one circuit or region are unintentionally transferred to another adjacent circuit or region due to physical mechanisms such as electromagnetic induction, capacitive coupling, or radiation. The spatial isolation provided by the aforementioned physical isolation bands can effectively increase the impedance of coupling paths and reduce the coupling coefficient, thereby significantly suppressing possible capacitive coupling, inductive coupling, or radiation coupling between temperature measurement areas, radio frequency areas, digital areas, and analog sensitive areas, ensuring that each functional area can operate independently and stably.

[0131] For example, please refer to Figure 7 , Figure 7 This diagram illustrates the noise comparison during automated operation of the NV color core current sensor based on nanocrystalline soft magnetic material and a superstructure comb ground, within the encapsulated protective structure of this embodiment. In this embodiment, the sensor is always dynamically protected by the encapsulation protective layer. The noise signal before suppression is shown in (a) with high noise superposition, and the noise signal after suppression is shown in (b) with high signal-to-noise ratio protected by this scheme. Experimental data shows that without noise suppression using the encapsulation protective structure 100, the signal is severely affected by high-frequency spike interference (extremely low SNR); after noise suppression using the encapsulation protective structure 100, the system's signal-to-noise ratio improvement is ΔSNR, calculated using the formula:

[0132]

[0133] in, Psignal / P noise_with_shielding For the signal-to-noise ratio after protection, P signal / P noise_raw The signal-to-noise ratio before protection.

[0134] In this embodiment, the solution of this application achieves spatial isolation between functional areas by setting physical isolation bands between the temperature measurement area, radio frequency area, digital area, and analog sensitive area within the integrated circuit layer 20. Specifically, when the temperature measurement area, radio frequency area, digital area, and analog sensitive area on the integrated circuit layer 20 are arranged in partitions, physical isolation bands are strategically placed between these partitions. This physical isolation band acts as a physical barrier, effectively increasing the path impedance of signal transmission between adjacent partitions, thereby weakening or blocking the propagation of electromagnetic fields between different partitions. For example, by increasing the physical distance between partitions or introducing low dielectric constant materials, parasitic capacitive coupling can be significantly reduced; by setting conductive shielding layers or grounding rings, inductive coupling and radiation coupling can be effectively suppressed. This spatial isolation mechanism ensures that when each functional area performs its respective task, the electromagnetic interference or noise it generates will not significantly affect the sensitive circuits of adjacent partitions, thereby ensuring that the magnetic field signal acquired by the diamond quantum sensing module 11 can be accurately measured by the processing module 21, improving the anti-interference capability and measurement accuracy of the entire current sensor packaging protection structure 100.

[0135] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0136] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A packaging and protection structure for an NV color center current sensor based on nanocrystalline soft magnetic material and a superstructure comb-like ground, the packaging and protection structure comprising a sensor layer, an integrated circuit layer, a substrate, and a heat sink stacked sequentially, wherein the sensor layer is provided with a diamond quantum sensing module, the integrated circuit layer is provided with a processing module, the diamond quantum sensing module acquires the magnetic field signal of the magnetic field of the current to be measured under external laser pumping, and the processing module is used to measure the magnitude of the current in the magnetic field of the current to be measured based on the magnetic field signal, characterized in that... The encapsulation and protection structure also includes: A stress buffer layer is disposed between the integrated circuit layer and the substrate, with one side surface of the stress buffer layer adjacent to the integrated circuit layer and the other side surface of the stress buffer layer adjacent to the substrate; The housing is a multi-layered physical shielding housing, and the sensor layer, the integrated circuit layer, the stress buffer layer, the substrate and the heat dissipation base are all disposed inside the housing; The substrate has multiple thermally conductive vias, which are used to connect one surface adjacent to the integrated circuit layer and the other surface away from the integrated circuit layer. A grounding busbar is provided within the substrate. The grounding busbar extends in a direction perpendicular to the stacking direction of the stress buffer layer and the substrate. The grounding busbar includes multiple sub-lines extending to the same side in a periodic sequence, forming a comb-like structure.

2. The encapsulation and protection structure according to claim 1, characterized in that, The encapsulation and protection structure also includes a shielding sleeve, which at least surrounds the diamond quantum sensing module to form a closed magnetic circuit. The relative permeability of the shielding sleeve is greater than or equal to 8.8 x 10⁻⁶. 4 .

3. The encapsulation and protection structure according to claim 2, characterized in that, The shielding sleeve is made of nanocrystalline alloy material.

4. The encapsulation and protection structure according to claim 1, characterized in that, In the comb-like structure, an equivalent capacitance is formed between two adjacent sub-circuits through electric field coupling. The sub-circuits generate self-inductance through current flow, and adjacent sub-circuits generate mutual inductance through reverse current coupling. The self-inductance and the mutual inductance are superimposed to form an equivalent inductance. The equivalent capacitance and the equivalent inductance constitute a resonant unit. Multiple resonant units are arranged periodically to form a space frequency notch filter.

5. The encapsulation and protection structure according to claim 1, characterized in that, The comb-like structure shields noise signals covering a frequency band from 150kHz to 30MHz.

6. The encapsulation and protection structure according to claim 1, characterized in that, The grounding busbar includes a main grounding busbar, and the multiple sub-circuits extend outward from the main grounding busbar. The interval between two adjacent sub-circuits on both sides of the main grounding busbar is 0.1 mm to 1 mm.

7. The encapsulation and protection structure according to claim 1, characterized in that, The integrated circuit layer is further provided with a temperature measurement area, a radio frequency area, a digital area and an analog sensitive area, which are arranged in sections within the integrated circuit layer.

8. The encapsulation and protection structure according to claim 7, characterized in that, The integrated circuit layer is also provided with a physical isolation band, which is located between the temperature measurement area, the radio frequency area, the digital area and the analog sensitive area. The physical isolation band reduces the coupling noise between adjacent partitions through spatial isolation.

9. The encapsulation and protection structure according to claim 1, characterized in that, The substrate is an aluminum nitride ceramic substrate.

10. The encapsulation and protection structure according to claim 1, characterized in that, The thermal conductivity of the substrate is k > 175 W / mK.

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