Semiconductor device and method for manufacturing the same

Abstract

The present invention provides a semiconductor device and a method for fabricating the same. In the semiconductor device, a first substrate includes a first through-hole extending through the first and second surfaces, and a second substrate includes a second through-hole extending through the third and fourth surfaces. A microwave transmission line is located on the third surface, and a microwave antenna having a diamond bottom surface with an NV color center is mounted on the second through-hole, coupling the microwave antenna to the microwave transmission line. A laser source element is located below the fourth surface, and a photodetector is located on the first surface. The present invention integrates a laser source with a diamond chip, using MEMS technology to implement an integrated magnetic field sensor, enabling mass production at low cost. The through-holes for the laser source and microwave antenna are aligned simultaneously, improving the flexibility and reliability of the magnetic field sensor. Furthermore, the angled sidewalls of the first through-hole enhance the fluorescence collection efficiency of the photodetector, thereby increasing the sensitivity of the magnetic field sensor. Finally, a long-pass filter and a reflective metal layer further enhance the sensitivity of the quantum magnetic field sensor at the same volume.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor integrated circuit manufacturing, and in particular relates to a semiconductor device and a manufacturing method thereof. Background Art

[0002] Magnetism, a fundamental physical property of objects, is closely related to our daily lives. Magnetic fields are applied in physics, geology, magnetic resonance imaging, power transmission, and other fields, providing important support for medical diagnosis, energy development, and transportation. Therefore, precise measurement of magnetic fields is extremely important. Compared with traditional fiber-optic, magnetoresistive, and Hall-effect magnetometers, magnetometers based on quantum effects are widely studied due to their higher sensitivity and ability to meet the needs of more accurate magnetic field measurements.

[0003] The superconducting quantum interference device based on the Josephson and flux quantization effects is one of the most sensitive vector magnetometers known to date, reaching 0.3fT·Hz. -1 / 2 ; Optically pumped magnetometers using alkali metal atomic vapor can reach 10fT·Hz -1 / 2 , and there is no zero drift, and the response speed is fast; the sensitivity of the spin exchange relaxation magnetometer is not affected by spin exchange relaxation and can reach 0.16fT·Hz -1 / 2 However, while these technologies have high sensitivity, they are also constrained by many factors: superconducting quantum interference devices need to operate in a cryogenic environment, and cryogenic systems are bulky and expensive; optically pumped magnetometers are scalar magnetometers, and the atomic vapor chamber needs to operate at 100°C, requiring additional heating devices; magnetometers without spin exchange relaxation have a contradiction between dynamic range and sensitivity, are incompatible with magnetic fields of the uT level and above, and require magnetic shielding devices.

[0004] The diamond NV color center, as a solid-state quantum magnetic sensing platform, can detect 10 -13 The ability to measure magnetic fields in the range of -10T, while also combining the advantages of high sensitivity and room temperature detection, has become a research hotspot in recent years. Initially based on optical platforms and desktop devices, diamond magnetic sensors can reach 195fT·Hz. -1 / 2 However, it sacrifices spatial resolution and is bulky, making it unsuitable for field measurements in outdoor environments. Subsequent improvements have resulted in diamond magnetic sensors based on fiber excitation, which are smaller in size but still require an external laser to provide laser pumping, as well as imaging equipment to align the laser and microwave antenna, making them unsuitable for portable testing.

[0005] Therefore, there is an urgent need for a structure or method for a magnetic field sensor that can meet high sensitivity requirements while achieving miniaturization and low-cost batch production.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of this application and facilitating the understanding of those skilled in the art. It cannot be assumed that the above technical solutions are well known to those skilled in the art simply because these solutions are described in the background technology part of this application. Summary of the Invention

[0007] In view of the above shortcomings of the prior art, an object of the present invention is to provide a semiconductor device and a method for manufacturing the same, so as to solve the problems of large size and high manufacturing cost of magnetic field sensors in the prior art.

[0008] To achieve the above object, the present invention provides a semiconductor device, comprising: a laser source element and a diamond chip;

[0009] The diamond chip includes a photodetector, a support structure, a diamond with an NV color center, and a microwave excitation structure;

[0010] The support structure includes a first substrate and a second substrate, the first substrate includes an opposing first surface, a second surface, and a first through hole extending through the first and second surfaces, and the second substrate includes an opposing third surface, a fourth surface, and a second through hole extending through the third and fourth surfaces; a projected area of ​​the first through hole on the second surface is greater than or equal to a projected area of ​​the diamond with NV color centers on the second surface, and a projected area of ​​the second through hole on the second surface is less than a projected area of ​​the diamond with NV color centers on the second surface;

[0011] The microwave excitation structure includes a microwave antenna and a microwave transmission line, wherein the microwave transmission line is located at a position on the third surface of the second substrate where the second through hole is not provided, and the microwave antenna is located on the bottom surface of the diamond with the NV color center, wherein the bottom surface of the diamond with the NV color center is mounted on the second through hole on the third surface via the first through hole, and the microwave antenna is coupled to the microwave transmission line;

[0012] The laser source element is located below the fourth surface of the second substrate, and is used to generate laser light from the fourth surface through the second through hole to reach the diamond with NV color centers; the photodetector is located on the first surface of the first substrate, and is used to receive a target fluorescence signal generated by the diamond with NV color centers when excited by microwaves from the microwave antenna and convert the target fluorescence signal into a photocurrent signal.

[0013] Optionally, the laser source element generates a laser with a wavelength of 450 nanometers to 570 nanometers.

[0014] Optionally, the diamond chip further includes a long-pass filter, which is located between the first surface of the first substrate of the photodetector box, and is used to filter out interference light that interferes with the photodetector receiving a target fluorescence signal generated by microwave excitation of the diamond with NV color centers.

[0015] Optionally, a reflective metal layer is provided on the sidewall of the first substrate, and the reflectivity of the reflective metal layer to the target fluorescent signal is greater than or equal to 90%.

[0016] Optionally, a sidewall of the first through hole forms a preset inclination angle with the first surface, and a diameter of the first through hole on the first surface is larger than a diameter of the first through hole on the second surface.

[0017] Optionally, the laser light generated by the laser source element coincides with the projection of the center point of the second through hole and the center point of the microwave antenna on the bottom surface of the diamond with the NV color center on the second surface.

[0018] Optionally, the semiconductor device further comprises a packaging tube shell and a tube shell pin, wherein the packaging tube shell is used to hermetically package the laser source element and the diamond chip; one end of the tube shell pin is located inside the packaging tube shell and forms corresponding electrical connections with the laser source element and the diamond chip through bonding wires, and the other end of the tube shell pin is located outside the packaging tube shell and leads out the corresponding electrical connections between the laser source element and the diamond chip.

[0019] The present invention further provides a method for preparing a semiconductor device, wherein the method is used to prepare any one of the semiconductor devices described above, and the method comprises:

[0020] Providing a support structure provided with a microwave transmission line and a diamond with an NV color center provided with a microwave antenna;

[0021] The bottom surface of the diamond with NV color center and provided with a microwave antenna is arranged on the third surface of the support structure through the first through hole of the support structure, so that a coupling connection is formed between the microwave antenna and the microwave transmission line, and the center point of the microwave antenna coincides with the projection of the center point of the second through hole on the second surface;

[0022] The long-pass filter and the photodetector are sequentially mounted on the first through hole of the first surface to obtain a diamond chip;

[0023] Fix the laser source element and the diamond chip on the tube shell base, and fix the diamond chip on the laser source element so that the laser generated by the laser source element coincides with the projection of the center of the microwave antenna on the second surface of the support structure; set bonding wires to electrically connect the electrical connection between the diamond chip and the laser source element with the tube shell pins of the tube shell base; set a tube shell cover plate and the tube shell base for airtight packaging to obtain a packaged tube shell, so that the laser source element and the diamond chip are airtightly packaged in the packaged tube shell.

[0024] Optionally, a method for preparing a support structure provided with the microwave transmission line includes:

[0025] providing a first substrate, the first substrate comprising a first surface and a second surface opposite to each other;

[0026] Disposing a first barrier layer on the first surface of the first substrate and a second barrier layer on the second surface of the first substrate;

[0027] Etching the first barrier layer, the first substrate, and the second barrier layer to obtain a first through hole penetrating the first barrier layer, the first substrate, and the second barrier layer;

[0028] Covering the sidewall surface of the first through hole with a reflective metal layer;

[0029] providing a second substrate, the second substrate comprising opposing third and fourth surfaces;

[0030] disposing a third barrier layer on the third surface of the second substrate;

[0031] disposing a patterned microwave transmission line on the third barrier layer;

[0032] Etching the microwave transmission line, the third barrier layer, and the second substrate to obtain a second through hole penetrating the microwave transmission line, the third barrier layer, and the second substrate;

[0033] The second surface of the first substrate is bonded to the third surface of the second substrate so that the central axes of the first through hole and the second through hole coincide with each other, thereby obtaining a support structure provided with a microwave transmission line.

[0034] Optionally, the method for obtaining the first through hole is: dry-etching the first barrier layer to obtain a patterned first barrier layer on the first surface of the first substrate; depositing a patterned mask layer on the patterned first barrier layer and the exposed first surface; wet-etching the first substrate using the mask layer as a mask, and obtaining a first through hole whose sidewalls have a preset inclination angle with the first surface through anisotropic wet etching.

[0035] As described above, the semiconductor device and the method for manufacturing the same of the present invention have the following beneficial effects:

[0036] By designing a semiconductor device that integrates a laser source with a diamond chip, the present invention can use standard MEMS technology to achieve a miniaturized, portable magnetic field sensor. This can be mass-produced, reducing production costs, and achieves high sensitivity while maintaining a small size, which is beneficial for applications in wearable and handheld products.

[0037] The present invention provides a through-hole structure in the semiconductor device that allows alignment between the laser source and the microwave antenna of the diamond chip directly through standard semiconductor processes. This achieves high-precision, compact alignment of the microwave antenna and laser source, improving the flexibility and reliability of the magnetic field sensor.

[0038] The present invention realizes the collection of target fluorescence signals generated by the excitation of the diamond side surface by the photodetector through the design of the inclined side wall of the first through hole, thereby improving the fluorescence collection efficiency of the photodetector and thus improving the sensitivity of the magnetic field sensor;

[0039] The present invention reduces the loss of target fluorescence signals and interference signals generated by microwave excitation of diamonds with NV color centers by providing a long-pass filter and a reflective metal layer, thereby further improving the sensitivity of quantum magnetic field sensors of the same volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Shown is a schematic side cross-sectional view of the semiconductor device structure in the present invention.

[0041] Figure 2 Shown is a schematic top cross-sectional view of the semiconductor device structure in the present invention.

[0042] Figure 3 The spectrum diagram shows the magnetic detection sensitivity of the semiconductor device structure in the present invention at different spectrum frequencies.

[0043] Figure 4 It shows a schematic structural diagram of setting a first substrate in an example of step 1 of the method for preparing a semiconductor device structure in the present invention.

[0044] Figure 5 It shows a schematic structural diagram of etching the first barrier layer in an example of step 1 of the method for preparing the semiconductor device structure of the present invention.

[0045] Figure 6 It shows a schematic structural diagram of setting a first through hole in an example of step 1 of the method for preparing a semiconductor device structure in the present invention.

[0046] Figure 7It shows a schematic structural diagram of providing a reflective metal layer in an example of step 1 of the method for preparing a semiconductor device structure in the present invention.

[0047] Figure 8 It shows a schematic structural diagram of setting a third barrier layer in step 1 of an example of the method for preparing a semiconductor device structure in the present invention.

[0048] Figure 9 It shows a schematic structural diagram of setting a microwave transmission line in an example of step 1 of the method for preparing a semiconductor device structure in the present invention.

[0049] Figure 10 It shows a schematic structural diagram of etching the third barrier layer in an example of step 1 of the method for preparing the semiconductor device structure of the present invention.

[0050] Figure 11 It shows a schematic structural diagram of setting a second through hole in an example of step 1 of the method for preparing a semiconductor device structure in the present invention.

[0051] Figure 12 It shows a schematic structural diagram of bonding the first substrate and the second substrate in step 1 of an example of the method for preparing the semiconductor device structure of the present invention.

[0052] Figure 13 It shows a schematic structural diagram of setting a microwave metal film in an example of step 1 of the method for preparing a semiconductor device structure in the present invention.

[0053] Figure 14 It shows a schematic structural diagram of a microwave antenna obtained in step 1 of an example of the method for preparing a semiconductor device structure in the present invention.

[0054] Figure 15 Shown is a schematic top view of the graphical distribution of a microwave antenna obtained in step 1 of an example of the method for preparing a semiconductor device structure in the present invention.

[0055] Figure 16 It shows a schematic structural diagram of setting diamonds to the support structure in step 2 of the method for preparing the semiconductor device structure of the present invention.

[0056] Figure 17 It shows a schematic structural diagram of providing a long-pass filter in step 3 of the method for preparing a semiconductor device structure in the present invention.

[0057] Figure 18 It shows a schematic structural diagram of setting a photodetector in step 3 of the method for preparing a semiconductor device structure in the present invention.

[0058] Figure 19It shows a schematic structural diagram of arranging the laser source element and the diamond chip to the tube shell base in step 4 of the method for preparing the semiconductor device structure of the present invention.

[0059] Figure 20 It shows a schematic structural diagram of setting bonding wires in step 4 of the method for preparing a semiconductor device structure in the present invention.

[0060] Figure 21 It is a schematic structural diagram showing the arrangement of a tube shell cover in step 4 of the method for preparing a semiconductor device structure according to the present invention.

[0061] Figure 22 It is a schematic diagram showing the structure of connecting a printed circuit board in an example of step 4 of the method for preparing a semiconductor device structure in the present invention.

[0062] Explanation of Figure Numbers

[0063] 10. Laser source element; 11. Laser diode heat sink;

[0064] 20. Photodetector; 21. Long-pass filter;

[0065] 30. Support structure; 31. First substrate; 32. First through hole; 33. Second substrate; 34. Second through hole; 35. Microwave transmission line; 36. Reflective metal layer; θ, preset tilt angle;

[0066] 40. Diamond chip; 41. Microwave antenna; 42. Diamond;

[0067] 50. Package tube shell; 51. Tube shell base; 52. Tube shell cover; 53. Tube shell pins; 54. Heat sink; 55. Laser diode electrode; 56. Photodetector electrode; 57. Printed circuit board; 58. Bonding wire;

[0068] 61. First barrier layer; 62. Second barrier layer; 63. Third barrier layer; 64. Microwave metal film; 65. Microwave metal layer. DETAILED DESCRIPTION

[0069] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention.

[0070] For example, when describing the embodiments of the present invention, schematic diagrams illustrating device structures may be partially enlarged for ease of explanation. These schematic diagrams are merely illustrative and should not limit the scope of the present invention. Furthermore, in actual production, three-dimensional dimensions, including length, width, and depth, should be included.

[0071] For convenience of description, spatially relative terms such as "under," "below," "below," "below," "above," and "upper" may be used herein to describe the relationship of one element or feature to other elements or features shown in the drawings. It will be understood that these spatially relative terms are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the drawings.

[0072] In the context of the present application, a structure described as a first feature being "above" a second feature may include embodiments where the first and second features are in direct contact, and may also include embodiments where additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0073] It should be noted that the illustrations provided in this embodiment are only used to schematically illustrate the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0074] In existing technologies, magnetometers based on quantum effects have higher sensitivity than traditional fiber-optic, magnetoresistive, and Hall-effect magnetometers, and are widely studied because they can meet the needs of more accurate magnetic field measurements. The superconducting quantum interference device based on the Josephson and flux quantization effects is one of the most sensitive vector magnetometers known to date, with a sensitivity of up to 0.3 fT·Hz. -1 / 2 However, superconducting quantum interference devices need to work in a low-temperature environment, and the low-temperature system is bulky and expensive. The optically pumped magnetometer using alkali metal atomic vapor can reach 10fT·Hz. -1 / 2 , and there is no zero drift, and the response speed is fast, but the optically pumped magnetometer is a scalar magnetometer, and the atomic vapor gas chamber needs to work in an environment of 100°C, which requires an additional heating device; the sensitivity of the non-spin exchange relaxation magnetometer is not affected by spin exchange relaxation and can reach 0.16fT·Hz -1 / 2 However, there is a contradiction between the dynamic range and sensitivity of the spin-exchange relaxation magnetometer, which is not compatible with magnetic fields of the uT level and above, and requires a magnetic shielding device.

[0075] The diamond 42NV (Nitrogen-Vacancy) color center can be used as a solid-state quantum magnetic sensing platform to detect 10 -13The ability to measure magnetic fields in the range of -10T, while also combining the advantages of high sensitivity and room temperature detection, has become a research hotspot in recent years. The Diamond 42 magnetic sensor, originally based on an optical platform and desktop equipment, can reach 195fT·Hz. -1 / 2 However, it sacrifices spatial resolution and has a large overall size, making it unsuitable for field measurements in outdoor environments. The subsequent improved diamond 42 magnetic sensor based on fiber excitation, although smaller in size, still requires an external laser to provide laser pumping. At the same time, since an external laser fiber is used to provide laser, an imaging device is also required to align the laser and the microwave antenna 41, which is also not conducive to portable testing. Moreover, the diamond 42 magnetic sensors in the prior art are all assembled after each component of the magnetic sensor is processed separately, which makes it difficult to use the standard semiconductor process in the prior art for preparation, resulting in a high production cost of the actual magnetic sensor and difficulty in further reducing the volume.

[0076] The present invention provides a semiconductor device, such as Figure 1-Figure 2 As shown, Figure 1 is a side sectional view of the semiconductor device, Figure 2 is a top cross-sectional view of the semiconductor device, which includes: a laser source element 10 and a diamond chip 40;

[0077] The diamond chip 40 includes a photodetector 20, a support structure 30, a diamond 42 with NV color centers, and a microwave excitation structure;

[0078] The support structure 30 includes a first substrate 31 and a second substrate 33. The first substrate 31 includes an opposing first surface, a second surface, and a first through hole 32 extending through the first and second surfaces. The second substrate 33 includes an opposing third surface, a fourth surface, and a second through hole 34 extending through the third and fourth surfaces. The projected area of ​​the first through hole 32 on the second surface is greater than or equal to the projected area of ​​the diamond 42 with an NV color center on the second surface. The projected area of ​​the second through hole 34 on the second surface is less than the projected area of ​​the diamond 42 with an NV color center on the second surface.

[0079] The microwave excitation structure includes a microwave antenna 41 and a microwave transmission line 35. The microwave transmission line 35 is located at a position on the third surface of the second substrate 33 where the second through hole 34 is not provided. The microwave antenna 41 is located on the bottom surface of the diamond 42 with NV color centers. The bottom surface of the diamond 42 with NV color centers is mounted on the second through hole 34 on the third surface through the first through hole 32. The microwave antenna 41 is coupled to the microwave transmission line 35.

[0080] The laser source element 10 is located below the fourth surface of the second substrate 33, and is used to generate laser light from the fourth surface through the second through hole 34 to reach the diamond 42 with NV color centers; the photodetector 20 is located on the first surface of the first substrate 31, and is used to receive the target fluorescence signal generated by the diamond 42 with NV color centers under the microwave excitation of the microwave antenna 41 and convert the target fluorescence signal into a photocurrent signal.

[0081] The present invention arranges the first through hole 32 in the first substrate 31 and the second through hole 34 in the second substrate 33 and their aperture sizes so that the diamond 42 is placed at the bottom of the first through hole 32 and rests on the second through hole 34. The first through hole 32 on the second surface is used to fix and protect the diamond 42, so that the MEMS process can be used to realize the small-volume integrated assembly of the diamond 42 magnetic field sensor and ensure the position stability of the diamond 42 therein. At the same time, by designing a semiconductor device integrating the laser source and the diamond chip 40, a magnetic field sensor with a built-in laser source is obtained. Standard MEMS technology can be used to realize the miniaturization and portability of the magnetic field sensor, which can be processed and manufactured in batches, reducing production costs. While maintaining a small volume, it can achieve a high sensitivity that meets the requirements of portable applications, which is conducive to the upgrade of wearable, handheld and other products. ; In addition, the design of setting the laser source and the microwave antenna 41 of the diamond chip 40 in the semiconductor device can directly perform process alignment when preparing the second through hole 34 and the microwave antenna 41 through standard semiconductor processes, thereby achieving high-precision, small-volume alignment of the microwave antenna 41 and the laser source position installation, without the need for additional imaging equipment to align the microwave antenna 41 and the laser source element 10, which again greatly reduces the volume and weight of the equipment required for the normal operation of the magnetic field sensor and improves the flexibility and reliability of the magnetic field sensor; finally, by setting the microwave antenna 41 on the bottom surface of the diamond 42, the original excitation of the microwave field can be achieved, reducing the e-exponential attenuation of the microwave field intensity as the distance from the diamond 42 increases, thereby effectively reducing the loss of microwave power and reducing the overall power consumption of the magnetic field sensor.

[0082] In one embodiment, the laser source element 10 generates a laser with a wavelength of 450 nm to 570 nm.

[0083] By setting the laser wavelength range, the present invention can ensure the precise control of the laser on the electron spin direction in the diamond 42NV color center, thereby achieving high-sensitivity sensing of magnetic field changes.

[0084] In one embodiment, the laser source element 10 is a laser diode, and the generated pump laser power is about 100 mW.

[0085] In one embodiment, Figure 1As shown, the diamond chip 40 also includes a long-pass filter 21, which is located between the photodetector 20 and the first surface of the first substrate 31. The long-pass filter 21 is used to filter out interference light that interferes with the photodetector 20 receiving the target fluorescence signal generated by the diamond 42 with NV color centers when excited by microwaves.

[0086] Specifically, the interference light includes the excitation light generated by the laser source element 10 and the 575-nanometer defect fluorescence generated simultaneously when the microwave antenna 41 excites the diamond 42 with NV color centers; because the defect fluorescence itself does not respond to changes in the magnetic field and cannot serve as the sensing signal of the magnetic field sensor, it is not the target fluorescence signal and needs to be filtered out.

[0087] The present invention provides a long-pass filter 21 to filter out interference light other than the target fluorescence signal generated by the diamond 42 with NV color centers under microwave excitation, thereby improving the receiving efficiency of the photodetector 20 for the target fluorescence signal, thereby improving the sensitivity of the semiconductor device as a magnetic field sensor.

[0088] In one embodiment, the cut-off frequency of the long-pass filter 21 is 632 nanometers, and the transmittance of the cut-off band is 10 -6 , it can filter out the defect fluorescence (NV0, neutral nitrogen vacancy color center) generated by the 532-nanometer green excitation light and the 575-nanometer diamond 42 with NV color center, and reduce the interference with the target fluorescence signal (NV-, negative nitrogen vacancy color center) with a wavelength of 635 nm emitted by the diamond 42 with NV color center after microwave excitation.

[0089] In one embodiment, the cutoff wavelength of the long-pass filter 21 is greater than 575 nanometers and less than 635 nanometers, so as to filter out the excitation light of 532 nanometers and the defect fluorescence of 575 nanometers; the transmittance of the cutoff band is 10 -6 -10 -4 .

[0090] In one embodiment, the thickness of the long-pass filter 21 is 1 micron to 25 microns.

[0091] In one embodiment, the diamond 42 with NV color centers has a thickness of 1 micron to 700 microns.

[0092] In one embodiment, the microwave antenna 41 is composed of more than one layer of metal film.

[0093] In one embodiment, the microwave antenna 41 is formed by a composite of multiple metal films.

[0094] In one embodiment, the material of the microwave antenna 41 includes gold and / or silver.

[0095] In one embodiment, the thickness of the microwave antenna 41 is 30 nanometers to 1000 nanometers.

[0096] In one embodiment, the microwave transmission line 35 is a silicon surface transmission line.

[0097] In one embodiment, the microwave antenna 41 performs microwave in-situ excitation on the diamond 42 , and the driving power required for the microwave antenna 41 is about 10 mW.

[0098] In one embodiment, the support structure 30 is made of silicon.

[0099] Specifically, the use of silicon materials can better adapt to the material supply and process equipment in the mature MEMS process, thereby improving the adaptability of the semiconductor device to batch production using the MEMS process and improving production efficiency.

[0100] In one embodiment, the first substrate 31 and the second substrate 33 are both four-inch silicon wafers.

[0101] Specifically, other suitable sizes and materials may be selected as the first substrate 31 and the second substrate 33 according to needs, and all are within the protection scope of the present invention.

[0102] In one embodiment, a projected area of ​​the first through hole 32 on the second surface is 0.25 square millimeters to 100 square millimeters.

[0103] In one embodiment, the thickness of the first substrate 31 is 300 micrometers to 700 micrometers.

[0104] In one embodiment, Figure 1 As shown, a reflective metal layer 36 is provided on the sidewall of the first substrate 31 , and the reflectivity of the reflective metal layer 36 to the target fluorescent signal is greater than or equal to 90%.

[0105] The present invention uses a reflective metal layer 36 to reflect scattered laser light and fluorescence back to the diamond 42 in the overall structure of the semiconductor device, thereby reducing to a certain extent the loss of the target fluorescence signal generated by the diamond 42 with NV color centers when excited by microwaves, thereby increasing the intensity of the target fluorescence signal and further improving the sensitivity of the quantum magnetic field sensor achievable under the same volume.

[0106] In one embodiment, the reflective metal layer 36 has a thickness of 30 nanometers to 1000 nanometers.

[0107] In one embodiment, the reflective metal layer 36 is a single-layer or multi-layer metal film plated with gold or silver.

[0108] Specifically, the reflective metal layer 36 uses metal to serve as a reflective layer for the target fluorescent signal to improve the collection efficiency of the target fluorescent signal, and is also used for the subsequent bonding of the first substrate 31 and the second substrate 33; a reflective layer of other materials can also be selected to reflect the target fluorescent signal, but the bonding effect between the first substrate 31 and the second substrate 33 may be poor, and an additional bonding layer for bonding needs to be set to improve the bonding strength. The deformation is within the scope of protection of the present invention.

[0109] In one embodiment, Figure 1 As shown, the sidewall of the first through hole 32 forms a preset inclination angle θ with the first surface, and the aperture of the first through hole 32 on the first surface is larger than the aperture of the first through hole 32 on the second surface.

[0110] The present invention utilizes the inclined sidewall design of the first through hole 32 to enable the photodetector 20 to collect the target fluorescence signal generated by the side excitation of the diamond 42, unlike the diamond 42 magnetic field sensor in the prior art which can only collect the target fluorescence signal excited by the front face of the diamond 42. This further reduces the loss of the target fluorescence signal, improves the target fluorescence signal intensity of the photodetector 20, and thus improves the sensitivity of the magnetic field sensor.

[0111] Specifically, the preset tilt angle θ is not equal to 90°, and the specific tilt angle of the preset tilt angle θ can be designed according to actual needs to meet the requirements for the collection efficiency of the target fluorescent signal.

[0112] In one embodiment, a projected area of ​​the second through hole 34 on the second surface is 100 square micrometers to 25 square millimeters.

[0113] In one embodiment, the thickness of the second substrate 33 is 300 micrometers to 700 micrometers.

[0114] In one embodiment, the laser light generated by the laser source element 10 coincides with the projection of the center point of the second through hole 34 and the center point of the microwave antenna 41 on the bottom surface of the diamond 42 with NV color center on the second surface.

[0115] The present invention aligns the laser light generated by the laser source element 10 with the center point of the second through hole 34, and aligns the center point of the microwave antenna 41 on the bottom surface of the diamond 42 with the center point of the second through hole 34. This allows the laser light generated by the laser source element 10 to be aligned with the microwave antenna 41 during the preparation of the semiconductor device, thereby avoiding the need for additional alignment and debugging of the laser light and the microwave antenna 41 by an external imaging device. This greatly reduces the volume and weight required by the magnetic field sensor, further achieving lightweight and miniaturization of the magnetic field sensor.

[0116] In one embodiment, the laser source element 10 is a light emitting diode or a laser diode.

[0117] Specifically, the laser source element 10 may also adopt other suitable structures that can generate a laser source and can be integrated and manufactured using a MEMS process, all of which are within the protection scope of the present invention.

[0118] In one embodiment, Figure 1-Figure 2 As shown, the laser diode is provided with a laser diode heat sink 11 to dissipate heat and improve the reliability of the laser diode.

[0119] In one embodiment, Figure 1-Figure 2 As shown, the laser diode is arranged under the support structure 30 by disposing a heat sink 54 , and the heat dissipation of the semiconductor device is achieved at the same time.

[0120] The present invention provides installation space for the laser heat sink below the support structure 30 by arranging the heat sink 54 and the laser diode heat sink 11 below the support structure 30 , while also serving as a heat conduction member to improve the heat dissipation performance of the semiconductor device.

[0121] In one embodiment, Figure 2 As shown, in the diamond chip 40, the electrical connection of the laser source element 10 includes the positive connection line and the negative connection line of the laser diode as the laser diode electrode 55 to provide driving current; the electrical connection of the microwave excitation structure includes the input end, output end and ground end of the microwave transmission line 35 to provide surface transmission radio frequency signal.

[0122] In one embodiment, Figure 2 As shown, the electrical connections of the photodetector 20 include a positive connection line and a negative connection line of the photodetector 20, which serve as photodetector electrodes 56 to provide a reverse bias voltage.

[0123] The present invention electrically connects the photodetector 20 to a reverse bias voltage so that the photodetector 20 operates in a photoconductive mode, thereby obtaining a wider bandwidth and a faster response speed, thereby further improving the sensitivity and response speed of the magnetic field sensor.

[0124] In one embodiment, Figure 1As shown, the semiconductor device further includes a packaging tube shell 50 and a tube shell pin 53. The packaging tube shell 50 is used to hermetically package the laser source element 10 and the diamond chip 40. One end of the tube shell pin 53 is located inside the packaging tube shell 50 and forms corresponding electrical connections with the laser source element 10 and the diamond chip 40 through bonding wires 58. The other end of the tube shell pin 53 is located outside the packaging tube shell 50 and leads out the corresponding electrical connections between the laser source element 10 and the diamond chip 40.

[0125] In one embodiment, Figure 1 As shown, the package tube shell 50 includes a tube shell base 51 and a tube shell cover 52 . The inner and outer surfaces of the package tube shell 50 are both provided with a heat conduction layer, and the heat conduction layer is insulated from the tube shell pins 53 .

[0126] The present invention hermetically seals the semiconductor device by providing a packaging tube shell 50, effectively preventing water vapor in the air from corroding and causing the electrical pins of the semiconductor device to short-circuit or open-circuit, thereby improving the reliability of the magnetic field sensor; at the same time, by providing a heat conduction layer, the heat conduction efficiency of the semiconductor device can be improved, thereby improving the heat dissipation capacity and the operating reliability of the semiconductor device.

[0127] Preferably, the heat conducting layer is made of a non-magnetic or low-magnetic material to reduce the receiving noise of the target fluorescence signal by the photodetector 20 .

[0128] In one embodiment, the thickness of the heat conducting layer is 1 micrometer to 10 micrometers.

[0129] In one embodiment, the heat conducting layer is metal.

[0130] In one embodiment, the heat conducting layer is a single-layer or multi-layer metal film made of gold or nickel.

[0131] In one embodiment, the housing pins 53 are radio frequency pins.

[0132] In one embodiment, the housing pins 53 can pass an electrical signal with a frequency of DC-4 GHz.

[0133] In one embodiment, the packaging leakage rate inside the packaging shell 50 is less than 5×10 -9 (Pa·m 3 ) / s.

[0134] In one embodiment, Figure 1 As shown, the semiconductor device further includes a printed circuit board 57 ; the printed circuit board 57 is electrically connected to the package pins 53 of the semiconductor device and is used for transmitting electrical signals among the laser source element 10 , the photodetector 20 and the microwave excitation structure.

[0135] In one embodiment, the printed circuit board 57 includes a transimpedance amplifier circuit, a lock-in amplifier and a data processor, one end of the transimpedance amplifier is electrically connected to the tube shell pin 53, the other end of the transimpedance amplifier is electrically connected to one end of the lock-in amplifier, and the other end of the lock-in amplifier is electrically connected to the data processor; the transimpedance amplifier circuit is used for the radio frequency signal transmission of the microwave excitation structure and the voltage conversion of the photocurrent signal obtained by the photodetector 20 to obtain a voltage signal; the lock-in amplifier is used to demodulate the voltage signal obtained by the transimpedance amplifier circuit to obtain a demodulated signal; the data processor is used to perform microwave sweep processing on the demodulated signal obtained by the lock-in amplifier to obtain the magnetic noise spectral density at different frequencies.

[0136] In one embodiment, the bandwidth of the lock-in amplifier is 1 KHz.

[0137] The present invention can optimize the sensitivity of a semiconductor device as a quantum magnetic field sensor by setting the bandwidth of the lock-in amplifier. Specifically, the smaller the bandwidth of the lock-in amplifier, the better the sensitivity.

[0138] In one embodiment, an external power source is electrically connected to the printed circuit board 57 to supply power to the printed circuit board 57 .

[0139] In one embodiment, the semiconductor device operates as a magnetic sensor to measure magnetic field changes as follows:

[0140] Laser excitation of the NV color center in the diamond 42 to produce fluorescence: When the semiconductor device operates as an integrated quantum magnetic sensor, an external power supply supplies power to the printed circuit board 57, thereby providing a constant current drive to the laser diode (laser source element 10), generating green laser light to pump the NV color center in the diamond 42. The ground-state particles in the NV color center in the diamond 42 are pumped to an excited state and then return to the ground state through radiative transition, generating fluorescence.

[0141] Different magnetic fields cause different changes in the optical detection magnetic resonance frequency between the two ground state energy levels of the Zeeman splitting of the NV color center: when a bias magnetic field (measured magnetic field) is applied to the semiconductor device, the electron spin ground state in the NV color center in the NV-charge state is changed to the m-state originally in the merger state. s = ±1 energy levels undergo Zeeman splitting, making m s =+1 and m s =-1The optical detection magnetic resonance frequency between the two energy levels produces 2γB NV The offset (difference), where γ is the gyromagnetic ratio, B NV is the projection component of the bias magnetic field on the NV color center axis;

[0142] Microwaves modulate the fluorescence signal generated by the excitation of the NV color center: the change in the corresponding optical detection magnetic resonance frequency when the spin precession frequency (νL) of the NV color center resonates with the microwave frequency can be used to obtain the size of the bias magnetic field projected on the NV color center axis; the modulated radio frequency signal generated by the microwave antenna 41 as a microwave source is transmitted to the bottom surface of the diamond 42 through the tube shell pin 53, the bonding wire 58 (metal), the microwave transmission line 35 and the microwave antenna 41 in sequence, and the NV color center of the diamond 42 excited by the laser is simultaneously driven by in-situ microwaves, and optical detection magnetic resonance occurs under the joint action of the laser, so that the microwave modulates the target fluorescence signal generated by the diamond 42. After passing through the long-pass filter 21, the target fluorescence signal modulated by the microwave resonance is received by the photodetector 20 and converted into a current signal;

[0143] The modulated signal received by the photodetector 20 is demodulated, screened, and converted into a sensitivity spectrum diagram: the current signal of the photodetector 20 is transmitted through the bonding wire 58 and the tube shell pin 53 to the transimpedance amplifier circuit on the surface of the printed circuit board 57, which is converted into a voltage signal and output to the phase-locked amplifier. After demodulation processing by the phase-locked amplifier, it is transmitted to the data processor (host computer) for data processing; wherein, the microwave antenna 41 performs microwave sweep frequency processing of 2.4GHz-3.2GHz on the NV center of the diamond 42, and finally the demodulated signal of the target fluorescence signal of the NV center of the diamond 42 in the four axes can be obtained after microwave modulation and phase-locked amplifier demodulation (representing the target fluorescence signal corresponding to different microwave resonance frequencies). The number of photoelectrons), the resonant frequency (energy level offset) of one of the demodulated signals (preferably the demodulated signal with the largest slope to achieve the greatest sensitivity) is selected as the optical detection magnetic resonance frequency during magnetic measurement; the amplitude spectral density of the demodulated signal can be obtained by Fourier transforming the demodulated voltage signal within 1s of the phase-locked amplifier, and then the slope of the demodulated signal (the rate of change between the intensity change of the target fluorescence signal and the change of the microwave resonance frequency) and the gyromagnetic ratio γ (γ = νL / B, B is the external magnetic field, νL is the spin precession frequency of the NV color center, and the spin precession frequency is equal to the change of the microwave resonance frequency) are converted into the magnetic noise spectral density of the system as a parameter to characterize the sensitivity of the diamond 42 quantum magnetometer, and finally the following is obtained: Figure 3 The demodulated signal is Fourier transformed and the corresponding magnetic detection sensitivity at different spectral frequencies is shown in the figure. The sensitivity reaches 5.5nT·Hz in the spectral frequency range of 10-1000Hz. -1 / 2 Magnetic detection sensitivity.

[0144] The present invention further provides a method for preparing a semiconductor device, wherein the method is used to prepare any one of the semiconductor devices described above, and the method comprises:

[0145] Step 1: providing a support structure 30 provided with a microwave transmission line 35 and a diamond 42 with an NV color center provided with a microwave antenna 41;

[0146] Step 2: The bottom surface of the diamond 42 with an NV color center and the microwave antenna 41 is disposed on the third surface of the support structure 30 through the first through hole 32 of the support structure 30, so that the microwave antenna 41 is coupled to the microwave transmission line 35, and the center point of the microwave antenna 41 coincides with the projection of the center point of the second through hole 34 on the second surface;

[0147] Step 3: sequentially placing the long-pass filter 21 and the photodetector 20 on the first through hole 32 of the first surface, thereby obtaining a diamond chip 40;

[0148] Step 4: Fix the laser source element 10 and the diamond chip 40 on the tube shell base 51, and fix the diamond chip 40 on the laser source element 10 so that the laser generated by the laser source element 10 coincides with the projection of the center of the microwave antenna 41 on the second surface of the support structure 30; set bonding wires 58 to electrically connect the electrical connection between the diamond chip 40 and the laser source element 10 and the tube shell pins 53 of the tube shell base 51; set a tube shell cover 52 and the tube shell base 51 to hermetically seal to obtain a package tube shell 50, so that the laser source element 10 and the diamond chip 40 are hermetically sealed in the package tube shell 50.

[0149] The following will describe in detail the method for preparing the semiconductor device of the present invention with reference to the accompanying drawings. It should be noted that the above sequence does not strictly represent the sequence of the method for preparing the semiconductor device protected by the present invention, and those skilled in the art may change it according to the actual preparation steps.

[0150] First, step 1 is performed to provide a support structure 30 provided with a microwave transmission line 35 and a diamond 42 with an NV color center provided with a microwave antenna 41.

[0151] In one embodiment, a method for preparing the support structure 30 provided with the microwave transmission line 35 includes:

[0152] Providing a first substrate 31, wherein the first substrate 31 includes a first surface and a second surface opposite to each other;

[0153] like Figure 4 As shown, a first barrier layer 61 is provided on the first surface of the first substrate 31 , and a second barrier layer 62 is provided on the second surface of the first substrate 31 ;

[0154] like Figure 5-Figure 6As shown, the first barrier layer 61, the first substrate 31 and the second barrier layer 62 are etched to obtain a first through hole 32 penetrating the first barrier layer 61, the first substrate 31 and the second barrier layer 62;

[0155] like Figure 7 As shown, the sidewall surface of the first through hole 32 is covered with a reflective metal layer 36 (the thickness of the reflective metal layer 36 in the figure is exaggerated for illustration and is not proportional to the actual thickness of the first substrate 31 and the first barrier layer 61);

[0156] Providing a second substrate 33, wherein the second substrate 33 includes a third surface and a fourth surface opposite to each other;

[0157] like Figure 8 As shown, a third barrier layer 63 is provided on the third surface of the second substrate 33;

[0158] like Figure 8-Figure 9 As shown, a patterned microwave transmission line 35 is provided on the third barrier layer 63;

[0159] like Figure 10-11 As shown, the microwave transmission line 35, the third barrier layer 63 and the second substrate 33 are etched to obtain a second through hole 34 that penetrates the microwave transmission line 35, the third barrier layer 63 and the second substrate 33;

[0160] like Figure 12 As shown, the second surface of the first substrate 31 is bonded to the third surface of the second substrate 33 so that the central axes of the first through hole 32 and the second through hole 34 coincide with each other, thereby obtaining a support structure 30 provided with a microwave transmission line 35 .

[0161] The present invention avoids the problem of gold-silicon eutectic during subsequent bonding of the first substrate 31 and the second substrate 33 by providing the first barrier layer 61 , the second barrier layer 62 , and the third barrier layer 63 , thereby improving process yield and product reliability.

[0162] In one embodiment, the first barrier layer 61 , the second barrier layer 62 , and the third barrier layer 63 are all made of silicon dioxide.

[0163] In one embodiment, the aperture of the first through hole 32 is slightly larger than the diameter of the diamond 42 with NV color centers, so that the diamond 42 with NV color centers can be placed on the third surface of the second substrate 33 through the first through hole 32 .

[0164] In one embodiment, the method for obtaining the first through hole 32 is: dry-etching the first barrier layer 61 to obtain a patterned first barrier layer 61 on the first surface of the first substrate 31; depositing a patterned mask layer on the patterned first barrier layer 61 and the exposed first surface; wet-etching the first substrate 31 using the mask layer as a mask, and obtaining a first through hole 32 whose sidewalls are at a preset inclination angle θ with the first surface through anisotropic wet etching.

[0165] In one embodiment, the mask layer is silicon nitride.

[0166] The present invention uses silicon nitride as a mask layer to protect the area outside the first through hole 32 from corrosion, thereby improving the morphology accuracy of the first through hole 32 obtained after the process and improving the overall device reliability.

[0167] In one embodiment, potassium hydroxide is used to perform anisotropic wet etching on the first substrate 31 .

[0168] In one embodiment, the preset tilt angle θ between the sidewall of the first through hole 32 and the first surface obtained by anisotropic etching is 54.7°.

[0169] The present invention can maximize the collection efficiency of the target fluorescent signal by setting the preset tilt angle θ to 54.7°, while ensuring the fixing and protective effect of the first through hole 32 on the diamond 42.

[0170] Specifically, the preset tilt angle θ may also be set to other appropriate angles according to requirements.

[0171] In one embodiment, when the sidewall surface of the first through hole 32 is covered with the reflective metal layer 36 , the reflective metal layer 36 also covers all exposed surfaces of the first substrate 31 .

[0172] The present invention deposits a reflective metal layer 36 on all exposed surfaces of the first substrate 31, which can be used for subsequent bonding of the first substrate 31 and the second substrate 33. At the same time, it avoids the need for a patterned deposition mask layer or etching process when only the reflective metal layer 36 is provided on the sidewalls of the first through hole 32, thereby improving process efficiency.

[0173] In one embodiment, a method for providing a patterned microwave transmission line 35 on the third barrier layer 63 includes: performing photolithography to obtain a patterned photoresist; depositing a microwave metal layer 65, filling metal in gaps between the patterned photoresists, and removing the photoresist and the metal deposited on the photoresist by a lift-off process, leaving only the patterned microwave metal layer 65 filling the gaps between the patterned photoresists, thereby obtaining a patterned microwave transmission line 35; or Figure 8As shown, a microwave metal layer 65 is first deposited to cover the third barrier layer 63; a photoresist is provided on the deposited microwave metal layer 65 and photolithography is performed to obtain a patterned photoresist; as shown Figure 9 As shown, the exposed microwave metal layer 65 is etched using the patterned photoresist as a mask to obtain the patterned microwave metal layer 65 as the microwave transmission line 35 .

[0174] In one embodiment, the method for obtaining the second through hole 34 is: firstly, a photoresist is provided on the microwave transmission line 35 and photolithography is performed to obtain a patterned photoresist; and the patterned photoresist is used as a mask to dry-etch the third barrier layer 63 and the second substrate 33 to obtain the second through hole 34.

[0175] In one embodiment, a method for preparing a diamond 42 with an NV color center and provided with a microwave antenna 41 includes:

[0176] Providing a diamond 42 having an NV color center;

[0177] like Figure 13 As shown, a microwave metal film 64 is provided on the bottom surface of the diamond 42 with NV color center, as shown in FIG. Figure 14 As shown, the microwave metal film 64 is patterned to obtain the microwave antenna 41.

[0178] In one embodiment, the metal film on the bottom surface of the diamond 42 with NV color centers is patterned by lift-off or dry etching to obtain the microwave antenna 41 .

[0179] Specifically, the graphical shape distribution of the microwave antenna 41 can be simulated and designed, such as Figure 15 The figure shows a top view of the patterned distribution of the microwave antenna 41. This patterned distribution makes the microwave field intensity distribution formed by the microwave antenna 41 on the surface of the diamond 42 more uniform, thereby improving the uniformity of the target fluorescence signal received by the photodetector 20, thereby improving the sensitivity of the magnetic field sensor.

[0180] Then, proceed to step 2, such as Figure 16 As shown, a diamond 42 with an NV color center is provided with a bottom surface of a microwave antenna 41 and is provided on the third surface of the support structure 30 through the first through hole 32 of the support structure 30, so that a coupling connection is formed between the microwave antenna 41 and the microwave transmission line 35, and the center point of the microwave antenna 41 coincides with the projection of the center point of the second through hole 34 on the second surface.

[0181] In one embodiment, the diamond 42 with NV color centers is placed on the third surface by flip-flop welding, and the contacting microwave antenna 41 and microwave transmission line 35 are welded to achieve metal connection.

[0182] Then, proceed to step 3, as Figure 17-18 As shown, the long-pass filter 21 and the photodetector 20 are sequentially mounted on the first through hole 32 of the first surface, thereby obtaining a diamond chip 40 .

[0183] In one embodiment, the long-pass filter 21 and the photodetector 20 are fixedly mounted on the first through hole 32 of the first surface by bonding or gluing.

[0184] In one embodiment, the long-pass filter 21 is prepared by depositing a high-refractive-index material and a low-refractive-index material on two surfaces of a glass sheet, respectively.

[0185] Specifically, the glass sheet has the same size as the first substrate 31 .

[0186] In one embodiment, the glass sheet is four inches.

[0187] Finally, proceed to step 4, such as Figure 19 As shown, the laser source element 10 and the diamond chip 40 are fixed on the tube shell base 51, and the diamond chip 40 is fixed on the laser source element 10, so that the laser generated by the laser source element 10 and the projection of the center of the microwave antenna 41 on the second surface of the support structure 30 coincide with each other; Figure 20 As shown, bonding wires 58 are provided to electrically connect the diamond chip 40 and the laser source element 10 to the housing pins 53 of the housing base 51; Figure 21 As shown, a package cover 52 is provided to be hermetically sealed with the package base 51 to obtain a package package 50 , so that the laser source element 10 and the diamond chip 40 are hermetically sealed in the package package 50 .

[0188] In one embodiment, the laser source element 10 is fixed to the bottom of the package 50 by soldering.

[0189] Specifically, the laser source element 10 can be assembled with the diamond chip 40 using a variety of welding methods.

[0190] In one embodiment, the packaging shell 50 hermetically seals the laser source element 10 , the photodetector 20 , the support structure 30 , the diamond with NV color centers 42 , and the microwave excitation structure by soldering or parallel sealing.

[0191] The present invention provides a packaging tube shell 50 to hermetically package the semiconductor device, which can effectively prevent the electrical pins from being short-circuited or broken due to corrosion by water vapor in the air, thereby improving the reliability of the magnetic field sensor.

[0192] In one embodiment, Figure 22 As shown, the packaged package shell 50 is assembled with the printed circuit board 57 by pin welding to achieve electrical connection with the printed circuit board 57.

[0193] In summary, the semiconductor device and preparation method of the present invention can be designed to integrate a laser source and a diamond chip into a semiconductor device, and standard MEMS technology can be used to obtain a miniaturized and portable magnetic field sensor. The device can be mass-produced, reducing production costs, and achieving high sensitivity while maintaining a small volume, which is conducive to application in wearable, handheld and other products. At the same time, by providing a through-hole structure in the semiconductor device that allows the laser source and the microwave antenna of the diamond chip to be aligned directly through standard semiconductor processes, high-precision and small-volume alignment of the microwave antenna and laser source positions is achieved, thereby improving the flexibility and reliability of the magnetic field sensor. In addition, by designing the inclined sidewall of the first through-hole, the photodetector can collect the target fluorescence signal generated by the diamond side excitation, thereby improving the fluorescence collection efficiency of the photodetector and thus improving the sensitivity of the magnetic field sensor. Finally, by providing a long-pass filter and a reflective metal layer, the loss of the target fluorescence signal generated by the diamond with NV color center under microwave excitation and the interference signal on the target fluorescence signal are reduced, further improving the sensitivity of the quantum magnetic field sensor under the same volume.

[0194] Therefore, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0195] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A semiconductor device, characterized in that: The semiconductor device comprises: a laser source element and a diamond chip; The diamond chip includes a photodetector, a support structure, a diamond with an NV color center, and a microwave excitation structure; The support structure includes a first substrate and a second substrate, the first substrate includes an opposing first surface, a second surface, and a first through hole extending through the first and second surfaces, and the second substrate includes an opposing third surface, a fourth surface, and a second through hole extending through the third and fourth surfaces; a projected area of ​​the first through hole on the second surface is greater than or equal to a projected area of ​​the diamond with NV color centers on the second surface, and a projected area of ​​the second through hole on the second surface is less than a projected area of ​​the diamond with NV color centers on the second surface; The microwave excitation structure includes a microwave antenna and a microwave transmission line, wherein the microwave transmission line is located at a position on the third surface of the second substrate where the second through hole is not provided, and the microwave antenna is located on the bottom surface of the diamond with the NV color center, wherein the bottom surface of the diamond with the NV color center is mounted on the second through hole on the third surface via the first through hole, and the microwave antenna is coupled to the microwave transmission line; The laser source element is located below the fourth surface of the second substrate, and is used to generate laser light from the fourth surface through the second through hole to reach the diamond with NV color centers; the photodetector is located on the first surface of the first substrate, and is used to receive a target fluorescence signal generated by the diamond with NV color centers when excited by microwaves from the microwave antenna and convert the target fluorescence signal into a photocurrent signal.

2. The semiconductor device according to claim 1, wherein The laser wavelength generated by the laser source element is 450 nanometers to 570 nanometers.

3. The semiconductor device according to claim 1 or 2, wherein: The diamond chip also includes a long-pass filter, which is located between the photodetector and the first surface of the first substrate. The long-pass filter is used to filter out interference light that interferes with the photodetector receiving a target fluorescence signal generated by microwave excitation of the diamond with NV color centers.

4. The semiconductor device according to claim 1, wherein A reflective metal layer is provided on the sidewall of the first substrate, and the reflectivity of the reflective metal layer to the target fluorescent signal is greater than or equal to 90%.

5. The semiconductor device according to claim 1, wherein A sidewall of the first through hole forms a preset inclination angle with the first surface, and a diameter of the first through hole on the first surface is larger than a diameter of the first through hole on the second surface. The semiconductor device according to claim 1 , wherein: The laser light generated by the laser source element coincides with the projection of the center point of the second through hole and the center point of the microwave antenna on the bottom surface of the diamond with the NV color center on the second surface.

7. The semiconductor device according to claim 1, wherein The semiconductor device also includes a packaging tube shell and a tube shell pin. The packaging tube shell is used to hermetically package the laser source element and the diamond chip. One end of the tube shell pin is located inside the packaging tube shell and forms corresponding electrical connections with the laser source element and the diamond chip through bonding wires. The other end of the tube shell pin is located outside the packaging tube shell and leads out the corresponding electrical connections between the laser source element and the diamond chip.

8. A method for preparing a semiconductor device, characterized in that: The preparation method is used to prepare the semiconductor device according to any one of claims 1 to 7, and the preparation method comprises: Providing a support structure provided with a microwave transmission line and a diamond with an NV color center provided with a microwave antenna; The bottom surface of the diamond with NV color center and provided with a microwave antenna is arranged on the third surface of the support structure through the first through hole of the support structure, so that a coupling connection is formed between the microwave antenna and the microwave transmission line, and the center point of the microwave antenna coincides with the projection of the center point of the second through hole on the second surface; Sequentially placing a long-pass filter and a photodetector on the first through hole of the first surface to obtain a diamond chip; A laser source element and a diamond chip are fixed on a tube shell base, and the diamond chip is fixed on the laser source element so that the laser generated by the laser source element coincides with the projection of the center of the microwave antenna on the second surface of the support structure; bonding wires are arranged to electrically connect the diamond chip, the laser source element and the tube shell pins of the tube shell base; a tube shell cover plate is arranged to hermetically seal the tube shell base to obtain a packaged tube shell, so that the laser source element and the diamond chip are hermetically sealed in the packaged tube shell.

9. The method for preparing a semiconductor device according to claim 8, wherein: The preparation method of the support structure provided with the microwave transmission line comprises: providing a first substrate, the first substrate comprising a first surface and a second surface opposite to each other; Disposing a first barrier layer on the first surface of the first substrate and a second barrier layer on the second surface of the first substrate; Etching the first barrier layer, the first substrate, and the second barrier layer to obtain a first through hole penetrating the first barrier layer, the first substrate, and the second barrier layer; Covering the sidewall surface of the first through hole with a reflective metal layer; providing a second substrate, the second substrate comprising opposing third and fourth surfaces; disposing a third barrier layer on the third surface of the second substrate; disposing a patterned microwave transmission line on the third barrier layer; Etching the microwave transmission line, the third barrier layer, and the second substrate to obtain a second through hole penetrating the microwave transmission line, the third barrier layer, and the second substrate; The second surface of the first substrate is bonded to the third surface of the second substrate so that the central axes of the first through hole and the second through hole coincide with each other, thereby obtaining a support structure provided with a microwave transmission line.

10. The method for manufacturing a semiconductor device according to claim 9, wherein: The method for obtaining the first through hole is: dry-etching the first barrier layer to obtain a patterned first barrier layer on the first surface of the first substrate; depositing a patterned mask layer on the patterned first barrier layer and the exposed first surface; wet-etching the first substrate using the mask layer as a mask, and obtaining a first through hole whose sidewalls have a preset inclination angle with the first surface through anisotropic wet etching.

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