A chip near-field magnetic field measurement system

Abstract

The present invention discloses a chip near-field magnetic field measurement system, relating to the field of magnetic field measurement technology. The system includes: a laser emission modulation device, an optical path adjustment module, a diamond plate, an electrically controlled two-dimensional translation stage, a CCD camera, and an electromagnetic shielding control device. The laser emission modulation device and the electromagnetic shielding control device are provided to emit modulated laser light and quantum state control microwaves, which interact with the near-field magnetic field of the measured chip area to generate a fluorescence signal. Based on the fluorescence signals corresponding to different measurement areas on the measured chip, the near-field magnetic field distribution of the measured chip is determined. By providing the laser emission modulation device and the electromagnetic shielding control device, the present invention can improve the measurement efficiency of the near-field magnetic field of large-area chips.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic field measurement, and in particular to a chip near-field magnetic field measurement system. Background Art

[0002] With the development of chip miniaturization, integrating more electronic components within the limited space of the chip has become the focus of chip technology. The increase in the number and types of electronic components has made the electromagnetic compatibility (EMC) of chips increasingly prominent. Measuring the near-field magnetic field distribution on the chip surface is an important method for analyzing EMC issues.

[0003] Currently, near-field magnetic field measurements on chip surfaces mostly rely on magnetometers with metal probes. Electromagnetic coupling between the metal probe and the chip can lead to inaccurate measurement results. Quantum magnetic measurement methods using non-metallic probes can overcome this problem. The nitrogen-vacancy (NV) color center method, among others, can measure at room temperature and requires simple equipment, making it increasingly widely used in electromagnetic measurement. However, existing solutions for measuring near-field magnetic fields on large chip surfaces often rely on point-by-point scanning with a single color center, which is slow and time-consuming. Summary of the Invention

[0004] The purpose of the present invention is to provide a chip near-field magnetic field measurement system, which can improve the measurement efficiency of the near-field magnetic field of a large-area chip.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A chip near-field magnetic field measurement system, comprising:

[0007] Laser emission modulation device, optical path adjustment module, diamond plate, electrically controlled two-dimensional translation stage, CCD camera and electromagnetic shielding control device;

[0008] The laser emission modulation device is arranged on the first input optical path of the optical path adjustment module; the laser emission modulation device is used to output modulated laser light;

[0009] The electrically controlled two-dimensional translation stage is disposed on the first output optical path and the second input optical path of the optical path adjustment module; the first output optical path and the second input optical path overlap, and the directions of optical signal transmission are opposite; the electrically controlled two-dimensional translation stage is used to carry the chip under test and adjust the measurement area of ​​the chip under test by horizontal sliding;

[0010] The diamond plate is arranged between the electrically controlled two-dimensional translation stage and the optical path adjustment module; when the chip under test is powered on, the diamond plate is within the near-field magnetic field of the measurement area of ​​the chip under test; the measurement area is the projection area of ​​the diamond plate on the chip under test;

[0011] The CCD camera is arranged on the second output light path of the light path adjustment module;

[0012] The electromagnetic shielding control device is respectively connected to the electrically controlled two-dimensional translation stage, the laser emission modulation device, the diamond plate and the CCD camera; the electromagnetic shielding control device is used to control the horizontal sliding of the electrically controlled two-dimensional translation stage; the electromagnetic shielding control device is also used to emit quantum state control microwaves to perform quantum state microwave modulation on the diamond plate;

[0013] The optical path adjustment module is configured to reflect the modulated laser light to the diamond sheet covering the chip under test; the optical path adjustment module is also configured to transmit a fluorescence signal to the CCD camera; the fluorescence signal is generated by the diamond sheet under the combined action of the modulated laser light, the quantum state control microwave, and the near-field magnetic field of the measurement area of ​​the chip under test;

[0014] The electromagnetic shielding control device is further used to determine the near-field magnetic field distribution of the chip under test based on the fluorescence signals corresponding to different measurement areas on the chip under test.

[0015] Optionally, the laser emission modulation device includes:

[0016] lasers and acousto-optic modulators;

[0017] The laser and the acousto-optic modulator are both connected to the electromagnetic shielding control device; the laser and the acousto-optic modulator are connected through a liquid core optical fiber; the acousto-optic modulator is connected to the optical path adjustment module through an optical fiber;

[0018] The laser is used to emit laser light;

[0019] The liquid core optical fiber is used to homogenize the laser to obtain homogenized laser light;

[0020] The acousto-optic modulator is used to modulate the homogenized laser light to obtain modulated laser light.

[0021] Optionally, the chip near-field magnetic field measurement system further includes: a microwave antenna;

[0022] The microwave antenna is connected to the diamond sheet;

[0023] The microwave antenna is used to receive the quantum state control microwave.

[0024] Optionally, the chip near-field magnetic field measurement system further includes:

[0025] Optical flat panels and pneumatically isolated optical tables;

[0026] The pneumatic vibration isolation optical platform is used to carry the optical flat plate, the laser, the electrically controlled two-dimensional translation stage and the electromagnetic shielding control device;

[0027] The optical plate is arranged perpendicular to the pneumatic vibration isolation optical platform; the optical plate is used to carry the acousto-optic modulator, the optical path adjustment module, the diamond plate, the microwave antenna and the CCD camera.

[0028] Optionally, the electromagnetic shielding control device includes:

[0029] Computer, image acquisition card and microwave control module;

[0030] The image acquisition card is connected to the CCD camera; the image acquisition card is used to acquire fluorescence signal images corresponding to different measurement areas on the chip under test;

[0031] The microwave control module is connected to the acousto-optic modulator and the microwave antenna respectively;

[0032] The computer is respectively connected to the image acquisition card, the microwave control module, the laser and the electrically controlled two-dimensional translation stage; the computer is used to control the laser to emit laser light; the computer is also used to control the microwave control module to modulate the laser light after homogenization to obtain modulated laser light; the computer is also used to control the microwave control module to emit quantum state control microwaves to perform quantum state microwave modulation on the diamond sheet; the computer is also used to determine the near-field magnetic field distribution of the chip under test based on the fluorescence signal images corresponding to different measurement areas on the chip under test.

[0033] Optionally, the microwave control module includes:

[0034] Power amplifiers, microwave generators and delay devices;

[0035] The time delay device is connected to the AOM, the microwave generator and the computer respectively; the time delay device is arranged on the pneumatic vibration isolation optical platform; the time delay device is used to generate a clock signal; the computer is used to control the AOM according to the clock signal;

[0036] The microwave generator is further connected to the power amplifier and the computer respectively; the computer is further used to control the microwave generator to emit quantum state control microwaves according to the clock signal;

[0037] The power amplifier is arranged in the microwave system box; the power amplifier is also connected to the microwave antenna; the power amplifier is used to perform power amplification processing on the quantum state control microwave.

[0038] Optionally, the electromagnetic shielding control device further includes:

[0039] Electromagnetic shielding storage box;

[0040] The electromagnetic shielding storage box is arranged on the pneumatic vibration isolation optical platform; a plurality of electromagnetic shielding storage compartments are arranged in the electromagnetic shielding storage box; the image acquisition card, the microwave system box and the microwave generator are respectively arranged in different electromagnetic shielding storage compartments.

[0041] Optionally, the optical path adjustment module includes:

[0042] Incident light lens group box, dichroic mirror, CCD front lens group box and lens group light shielding box;

[0043] The lens assembly light-shielding box is arranged on the optical plate;

[0044] The dichroic mirror is arranged in the lens group light-shielding box; the lens group light-shielding box is provided with a first mounting hole, a second mounting hole and a light-through hole; the first mounting hole is arranged on the first input light path of the dichroic mirror; the light-through hole is arranged on the first output light path and the second input light path of the dichroic mirror; the first output light path and the second input light path coincide with each other and the directions of light signal transmission are opposite; the second mounting hole is arranged on the second output light path of the dichroic mirror;

[0045] The incident light lens assembly is arranged at the first mounting hole; the incident light lens assembly is connected to the acousto-optic modulator; the incident light lens assembly is used to modulate the modulated laser into a laser spot;

[0046] The CCD front lens assembly box is arranged at the second mounting hole; the CCD front lens assembly box is arranged on the input light path of the CCD camera.

[0047] Optionally, the incident light lens assembly cartridge includes:

[0048] A light-shielding housing and a light-collecting mirror, a field stop, an aperture stop and a condenser lens sequentially arranged in the light-shielding housing;

[0049] The light-shielding housing is connected to the acousto-optic modulator.

[0050] Optionally, the chip near-field magnetic field measurement system further includes: a fixture;

[0051] The clamp is rotatably arranged on the optical plate; the clamp is used to fix the diamond plate and adjust the angle of the diamond plate.

[0052] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0053] The present invention provides a chip near-field magnetic field measurement system, which emits modulated laser and quantum state controlled microwaves by setting a laser emission modulation device and an electromagnetic shielding control device, and generates a fluorescence signal under the interaction with the near-field magnetic field of the measurement area of ​​the chip under test. The near-field magnetic field distribution of the chip under test is determined based on the fluorescence signals corresponding to different measurement areas on the chip under test, which can improve the measurement efficiency of the near-field magnetic field of large-area chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0055] Figure 1 Schematic diagram of the structure of the chip near-field magnetic field measurement system in an embodiment of the present invention;

[0056] Figure 2 This is a schematic diagram of the structure of an electromagnetic shielding storage box in an embodiment of the present invention;

[0057] Figure 3 Schematic diagram of the incident light lens assembly structure in an embodiment of the present invention;

[0058] Figure 4 Schematic diagram of the CCD front lens assembly structure in an embodiment of the present invention;

[0059] Figure 5 This is a schematic diagram of the structure of a microwave system box in an embodiment of the present invention;

[0060] Figure 6 Schematic diagram of the structure of an electrically controlled two-dimensional translation stage in an embodiment of the present invention;

[0061] Figure 7 Schematic diagram of the lens assembly light shielding box structure in an embodiment of the present invention;

[0062] Figure 8 Schematic diagram of laser spot in an embodiment of the present invention;

[0063] Figure 9 Schematic diagram of the measurement area in an embodiment of the present invention;

[0064] Figure 10 A signal diagram in an embodiment of the present invention;

[0065] Figure 11 Schematic diagram of the large-area chip measurement area in an embodiment of the present invention;

[0066] Figure 12Schematic diagram of the movement route of the electrically controlled two-dimensional translation stage for measuring large-area chips in an embodiment of the present invention;

[0067] Figure 13 Schematic diagram of the near-field magnetic field fusion process corresponding to the measurement area in an embodiment of the present invention.

[0068] Explanation of reference numerals: 1-laser; 2-liquid core optical fiber; 3-acousto-optic modulator; 4-optical fiber; 5-incident light lens assembly box; 6-dichroic mirror; 7-CCD front lens assembly box; 8-lens assembly light shielding box; 9-optical flat plate; 10-diamond plate; 11-microwave antenna; 12-test chip; 13-electrically controlled two-dimensional translation stage; 14-CCD camera; 15-electromagnetic shielding storage box; 16-computer; 17-image acquisition card; 18-micro Wave system box; 19-microwave generator; 20-delay device; 21-pneumatic vibration isolation optical platform; 22-communication cable; 23-fiber optic adapter; 24-light collecting mirror; 25-field diaphragm; 26-aperture diaphragm; 27-condenser; 28-objective lens; 29-filter; 30-microwave switch; 31-isolator; 32-power amplifier; 33-lens group box mounting hole; 34-light hole; 35-light shielding shell; 36-laser spot. DETAILED DESCRIPTION

[0069] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0070] The purpose of the present invention is to provide a chip near-field magnetic field measurement system, which can improve the measurement efficiency of the near-field magnetic field of a large-area chip.

[0071] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0072] Example

[0073] like Figure 1As shown, this embodiment provides a chip near-field magnetic field measurement system, including: a laser emission modulation device, an optical path adjustment module, a diamond plate 10, an electrically controlled two-dimensional displacement stage 13, a CCD camera 14 and an electromagnetic shielding control device; the laser emission modulation device is arranged on the first input optical path of the optical path adjustment module; the laser emission modulation device is used to output modulated laser; the electrically controlled two-dimensional displacement stage is arranged on the first output optical path and the second input optical path of the optical path adjustment module; the first output optical path and the second input optical path coincide with each other and the directions of optical signal transmission are opposite; the electrically controlled two-dimensional displacement stage is used to carry the chip under test 12 and adjust the measurement area of ​​the chip under test by horizontal sliding; the diamond plate is arranged between the electrically controlled two-dimensional displacement stage and the optical path adjustment module; the diamond plate is in the near-field magnetic field range of the measurement area of ​​the chip under test when the chip under test is powered on; the measurement area is the area where the diamond plate is in the near-field magnetic field of the measurement area of ​​the chip under test The projection area on the chip under test; the CCD camera is arranged on the second output optical path of the optical path adjustment module; the electromagnetic shielding control device is respectively connected to the electrically controlled two-dimensional displacement stage, the laser emission modulation device, the diamond plate and the CCD camera; the electromagnetic shielding control device is used to control the horizontal sliding of the electrically controlled two-dimensional displacement stage; the electromagnetic shielding control device is also used to emit quantum state control microwaves to perform quantum state microwave modulation on the diamond plate; the optical path adjustment module is used to reflect the modulated laser to the diamond plate covering the chip under test; the optical path adjustment module is also used to transmit the fluorescence signal to the CCD camera; the fluorescence signal is generated by the diamond plate under the combined action of the modulated laser, the quantum state control microwave and the near-field magnetic field of the measurement area of ​​the chip under test; the electromagnetic shielding control device is also used to determine the near-field magnetic field distribution of the chip under test based on the fluorescence signals corresponding to different measurement areas on the chip under test.

[0074] Among them, the laser emission modulation device includes: a laser 1 and an acousto-optic modulator 3; the laser and the acousto-optic modulator are both connected to the electromagnetic shielding control device; the laser and the acousto-optic modulator are connected through a liquid core optical fiber 2; the acousto-optic modulator is connected to the optical path adjustment module through an optical fiber 4; the laser is used to emit laser light; the liquid core optical fiber is used to homogenize the laser light to obtain homogenized laser light; the acousto-optic modulator is used to modulate the homogenized laser light to obtain modulated laser light.

[0075] The present invention provides a chip near-field magnetic field measurement system, which also includes a microwave antenna 11, an optical plate 9, and a pneumatic isolation optical platform 21. The microwave antenna is connected to a diamond plate and is used to receive quantum state control microwaves. The pneumatic isolation optical platform is used to carry the optical plate, a laser, an electrically controlled two-dimensional translation stage, and an electromagnetic shielding control device. The optical plate is arranged perpendicular to the pneumatic isolation optical platform and is used to carry an acousto-optic modulator, an optical path adjustment module, a diamond plate, a microwave antenna, and a CCD camera.

[0076] Specifically, the electromagnetic shielding control device includes: a computer 16, an image acquisition card 17 and a microwave control module; the image acquisition card is connected to a CCD camera; the image acquisition card is used to acquire fluorescence signal images corresponding to different measurement areas on the chip under test; the microwave control module is respectively connected to an acousto-optic modulator and a microwave antenna; the computer is respectively connected to the image acquisition card, the microwave control module, the laser and the electrically controlled two-dimensional displacement stage through a communication cable 22; the computer is used to control the laser to emit laser light; the computer is also used to control the microwave control module to modulate the homogenized laser light to obtain modulated laser light; the computer is also used to control the microwave control module to emit quantum state control microwaves to perform quantum state microwave modulation on the diamond sheet; the computer is also used to determine the near-field magnetic field distribution of the chip under test based on the fluorescence signal images corresponding to different measurement areas on the chip under test.

[0077] Among them, the microwave control module includes: a power amplifier, a microwave generator 19 and a delay device 20; the delay device is respectively connected to the acousto-optic modulator, the microwave generator 32 and the computer; the delay device is arranged on a pneumatic vibration-isolating optical platform; the delay device is used to generate a clock signal; the computer is used to control the acousto-optic modulator according to the clock signal; the microwave generator is also respectively connected to the power amplifier and the computer; the computer is also used to control the microwave generator to emit quantum state control microwaves according to the clock signal; the power amplifier is arranged in the microwave system box 18; the power amplifier is also connected to the microwave antenna; the power amplifier is used to perform power amplification processing on the quantum state control microwaves.

[0078] In addition, the electromagnetic shielding control device further comprises: an electromagnetic shielding storage box 15; the electromagnetic shielding storage box is arranged on the pneumatic vibration isolation optical platform; Figure 2 The electromagnetic shielding storage box is provided with a plurality of electromagnetic shielding storage compartments; the image acquisition card, the microwave system box and the microwave generator are respectively arranged in different electromagnetic shielding storage compartments.

[0079] Specifically, the optical path adjustment module includes: an incident light lens group box 5, a dichroic mirror 6, a CCD front lens group box 7 and a lens group light-shielding box 8; the lens group light-shielding box is arranged on an optical plate; the dichroic mirror is arranged in the lens group light-shielding box; the lens group light-shielding box is provided with a lens group box mounting hole 33 (including a first mounting hole and a second mounting hole) and a light-through hole 34; the first mounting hole is arranged on the first input optical path of the dichroic mirror; the light-through hole is arranged on the first output optical path and the second input optical path of the dichroic mirror; the first output optical path and the second input optical path coincide and the directions of optical signal transmission are opposite; the second mounting hole is arranged on the second output optical path of the dichroic mirror; the incident light lens group box is arranged at the first mounting hole; the incident light lens group box is connected to the acousto-optic modulator; the incident light lens group box is used to modulate the modulated laser into a laser spot 36; the CCD front lens group box is arranged at the second mounting hole; the CCD front lens group box is arranged on the input optical path of the CCD camera.

[0080] Furthermore, if Figure 3 The incident light lens assembly box includes: a light-shielding shell and a light-collecting mirror 24, a field diaphragm 25, an aperture diaphragm 26 and a condenser 27 arranged in sequence in the light-shielding shell; the optical fiber adapter 23 on the light-shielding shell is connected to the acousto-optic modulator.

[0081] In addition, the chip near-field magnetic field measurement system provided by the present invention further includes: a fixture; the fixture is rotatably arranged on the optical plate; the fixture is used to fix the diamond piece and adjust the angle of the diamond piece.

[0082] In the present invention, a high-power laser with a wavelength of 532 nm is used to excite the diamond color center; a liquid core optical fiber is used to homogenize the Gaussian distribution laser; an acousto-optic modulator is used to convert the continuous laser into a modulated laser; an optical fiber is used to transmit the modulated laser to the incident light lens assembly; the incident light lens assembly is mainly responsible for converting the homogenized laser into a circular light spot with a diameter of 3 mm; the dichroic mirror reflects the laser generated in the incident light lens assembly onto the diamond plate, and transmits the fluorescence emitted from the diamond plate to the CCD front lens assembly, such as Figure 4 , a filter 29 is installed inside the CCD front lens group box to filter out stray light, and an objective lens 28 is also installed for CCD imaging. Figure 7 The lens group light shielding box is used to install the incident light lens group box, dichroic mirror and front lens group box. There are mounting holes for the incident light lens group box and the front lens group box on the top and left sides, and a light hole on the bottom to provide a light-shielding environment for the internal components. The optical plate is installed vertically to provide installation locations for the acousto-optic modulator, optical fiber, incident light lens group box, dichroic mirror, front lens group box, lens group light shielding box and CCD camera. The diamond sheet provides NV color centers for quantum magnetic imaging; the microwave antenna is used to control the quantum state of the NV color center; such as Figure 6 The electronically controlled two-dimensional displacement stage is used for displacement of the chip during imaging of different regions. The electromagnetic shielding storage box is a three-layer structure made of non-magnetic aluminum and is used to store components of the microwave system. The computer contains control software and image processing software for controlling the laser, microwave source, and electronically controlled displacement stage, as well as for data processing and image processing. The image acquisition card is used for image acquisition. Figure 5 The microwave system box houses the electromagnetically isolated power amplifier, isolator 31, and microwave switch 30. The microwave source provides microwaves for microwave control of the diamond color center. The time delayer provides timing signals for system timing control. The pneumatic isolation platform provides pneumatic isolation and mounting holes for all components. Communication cables enable data exchange and transmission of control information between connected components.

[0083] The installation position and connection relationship are as follows: the pneumatic isolation optical platform is at the bottom of the entire system. The laser, delay device, and electromagnetic shielding storage box are placed above the pneumatic isolation optical platform. The electrically controlled two-dimensional translation stage is fixed to the optical platform with screws. The optical plate is mounted vertically above the optical platform. The liquid-core optical fiber connects the laser and the acousto-optic modulator (AOM) via a dedicated interface. The AOM is directly mounted on the optical plate. The optical fiber connects the AOM 3 and the incident lens assembly via an optical fiber interface. The incident lens assembly is placed in front of the CCD through the lens assembly assembly. The dichroic mirror is mounted in the lens assembly light shielding box. The lens assembly mounting hole is located on the side of the light shielding box, and the light aperture is located at the bottom of the light shielding box. The light shielding box is installed in front of the optical plate. The diamond plate is mounted on the optical plate with an adjustable bracket, directly below the light aperture of the lens assembly light shielding box. The microwave antenna is mounted to the right of the diamond plate. The chip under test is placed above the electrically controlled two-dimensional translation stage and below the diamond plate. The computer, image acquisition card, microwave system box and microwave source are placed in the electromagnetic shielding storage box from top to bottom. The microwave switch, isolator and microwave source are connected in sequence. The microwave switch is placed on the first layer of the microwave system box 18, and the isolator and microwave source are placed on the second layer.

[0084] Specifically, the use process of the chip near-field magnetic field measurement system is as follows:

[0085] Step 1: Power on and test the device

[0086] Turn on the equipment power, power the computer, laser source, microwave source, and time delay device, start the measurement and control software and image acquisition and processing software on the computer, and use the measurement and control software to check whether the laser control and microwave source control are normal, check whether the delay device output and input are normal. Use the image acquisition and processing software to check whether the CCD is working properly.

[0087] Step 2: Diamond Color Center to Axis

[0088] Turn on the laser, turn on the CCD camera, turn on the time delay device and computer control software, use the software to control the laser output, and irradiate the laser onto the diamond piece through the liquid core optical fiber and the incident lens group. Adjust the angle of the diamond piece fixture and observe the fluorescence signal collected by the CCD camera. Fix the fixture when the collected fluorescence signal is the strongest.

[0089] Step 3: Laser Homogenization

[0090] Magnetic field measurement is performed using simultaneous excitation of multiple color centers. To ensure sufficient laser light power density on each color center of the irradiated surface and uniformity and synchronization of the excitation of the color centers, after the laser is turned on, the laser enters the liquid core fiber to homogenize the laser light emitted by the laser.

[0091] Step 4: Laser Modulation

[0092] The laser light homogenized by the liquid core fiber enters the acousto-optic modulator, and a clock signal is generated by a delay device. The computer controls the acousto-optic modulator according to the clock signal, turning the continuous laser light into a modulated laser light.

[0093] Step 5: Kohler Illumination System Adjustment

[0094] The modulated laser signal enters the incident lens assembly and becomes a uniform circular spot. The spot diameter is determined according to the size of the diamond piece 10. The diameter is generally the diameter of the inscribed circle of the diamond piece, such as Figure 8 .

[0095] In order to obtain this light spot, it is necessary to adjust the two apertures in the incident lens group box. The incident lens group box structure includes a collecting mirror, a field diaphragm, an aperture diaphragm and a condenser.

[0096] The iris can be adjusted according to the formula. First, the aperture diaphragm D needs to be determined. 孔 Size:

[0097] D 孔 =2F 聚 U (1)

[0098] Among them, U is the lens size of the condenser, F 聚 is the focal length of the condenser. Next, determine the position of the field stop, where the field stop position L2 is:

[0099] L2=LF 聚 / (F 聚 -L) (2)

[0100] Among them, L is the optical path distance from the condenser to the object surface, that is, the diamond plate. Next, determine the size of the field stop. This step determines whether the spot size coming out of the lens group meets the requirements. The field stop D 视 The size is:

[0101] D 视 =2 μL2 / L (3)

[0102] Where y is the radius of the light spot, which is 1.5 mm in this device.

[0103] Step 6: Quantum State Microwave Modulation

[0104] The uniformly circular light spot generated by the incident lens array illuminates the diamond disc, exciting the color centers therein and causing them to emit red fluorescence. At this point, a computer controls the microwave source, following a clock signal from a time delay device, to emit the desired microwave signal. This signal is amplified by a power amplifier and then enters the microwave antenna, where it controls the quantum state of the diamond color centers.

[0105] Step 7: Quantum state manipulation

[0106] Diamond color centers contain two quantum states, 0 and ±1. Quantum state manipulation aims to alter the ratio of these two states so that the arrangement of these states reflects magnetic field information. Specifically, after the color centers in a diamond disc are excited by 532nm laser light, their quantum states change from ground state to excited state. Because the excited state is unstable, this quantum state automatically falls back to the ground state and emits red fluorescence at 637nm. The ground state consists of 0 and ±1 states. During the fallback of the ±1 state, 30% of the quanta first reach a transient state and then fall back to the ground state. These quanta do not emit light during this fallback process, resulting in the ±1 state quanta emitting approximately 30% less fluorescence than the 0 state quanta. There is an energy difference between the 0 and ±1 states. This energy difference will be compensated by the external microwave field of a specific frequency. That is, under the microwave field of a specific frequency, the quantum state will be reversed from 0 to ±1, which will cause the brightness of the diamond piece in the CCD camera to drop by about 30% at this specific frequency. This frequency is determined by the measured magnetic field. When it is determined that the quantum state controls the microwave frequency of the antenna when the brightness of the diamond fluorescence decreases, the measured magnetic field value can be known.

[0107] Step 8: Power on the Chip

[0108] Place the chip under test on the electrically controlled two-dimensional translation stage, then power it up to keep it in normal working order. Use a computer to control the translation stage. If the chip surface area is smaller than the diamond sheet, move it directly under the diamond sheet. The device can obtain the chip's near magnetic field data in one measurement. If it is a large-area chip, that is, the chip's surface area is larger than the diamond sheet, place the chip and the inscribed square of the light spot in the same way. Figure 9 .

[0109] Step 9: Decouple the sequence control laser source, microwave system and CCD camera for signal acquisition

[0110] After completing the excitation light path setting and chip placement, use the computer to control the laser source, microwave system, and CCD camera to start working in sequence. The working time and working order of the three are determined by the dynamic decoupling sequence used in the detection. The following is an example of a simple decoupling sequence. Figure 10 As shown: Figure 10From top to bottom in the figure, the microwave control sequence, laser control signal, and CCD camera control signal are shown. For the microwave control sequence, when the delay device generates the clock signal shown above, the computer converts this clock signal into a control signal, controlling the microwave source to emit microwave signals at the rectangular location. Similarly, for the laser control signal, when the signal is at a high level, the laser emits laser light. For the CCD camera control signal, when the signal is at a high level, the CCD camera begins collecting signals. Under the combined influence of the laser, the quantum state control microwave, and the near-magnetic field on the chip surface, the diamond disc emits a fluorescence signal containing information about the near-magnetic field on the chip surface. This signal enters the CCD front lens group.

[0111] After being attenuated by this lens group, the fluorescence signal enters the CCD camera and is collected within the CCD camera's acquisition time. The acquisition process is typically repeated N times, where N depends on the CCD camera's ion trap capacity. Before the trap is full, a larger N value results in greater contrast in the collected signal.

[0112] Step 10: The electronically controlled two-dimensional translation stage drives the chip to start moving

[0113] like Figure 11 The computer calculates the moving step length of the two-dimensional translation stage according to the chip area. The side length of the square inscribed in the spot is L3, the width of the chip is L4, and the length is L5. Calculation:

[0114] L4 / L3=n…x.

[0115] L5 / L3=m…y1.

[0116] Where n and m are integers, x and y1 are remainders, and then we calculate:

[0117] L4 / (n+1)=k.

[0118] L5 / (m+1)=z.

[0119] Among them, k and z are the moving steps of the chip in its width and length directions. The path of chip movement is serpentine, as shown in the following example: Figure 12 ,If the chip has irregular parts, then construct a rectangle according to the maximum length and width of the chip.

[0120] Step 11: Data Processing

[0121] After collecting fluorescence data containing the near-magnetic field information of the chip under test using a CCD camera and an image acquisition card, the fluorescence data needs to be processed. First, the fluorescence data at each location is integrated over time, and the measured information is the relative value of the magnetic field strength. This data needs to be compared with preset standard points to obtain the absolute value of the near-magnetic field at each point.

[0122] Step 12: Image Processing

[0123] Through data processing, a magnetic field map is obtained. The map contains position information and magnetic field strength information. By adding color gradation to the magnetic field information, a magnetic field imaging map can be generated. This map is a magnetic field imaging map when the chip stops moving and resides under the diamond piece. To obtain the near-field magnetic field imaging map of the entire chip, it is necessary to perform an image stitching of the magnetic field imaging of multiple regions. According to the plan for chip displacement measurement, each regional magnetic field map will have overlapping parts with adjacent magnetic map data. Using the image stitching algorithm, the overlapping parts of the data are used as stitching targets to complete the image stitching, and finally the near-field magnetic field imaging map of the large-area chip is obtained. The stitching result is as follows: Figure 13 Image stitching is divided into four steps: image matching, reprojection, stitching and fusion. First, the positional relationship of several images needs to be determined and arranged according to the displacement direction of the two-dimensional translation stage. Then, these images are converted to a coordinate system through the geometric transformation of the image. Then, a larger canvas is generated by merging the pixel values ​​of the overlapping parts and keeping the pixel values ​​without overlapping. Finally, in order to avoid discontinuous parts in the image, that is, to avoid the appearance of seams, the stitching algorithm is used to optimize the image.

[0124] The present invention adopts a quantum measurement solution to measure the near-field magnetic field of the chip, which has the advantages of high sensitivity, non-invasiveness and non-destructiveness, and the solution avoids the use of metal probes, which can avoid inaccurate measurement results due to coupling. Diamond NV color center is used as the material for quantum measurement, which has the advantage of being able to complete detection at room temperature, does not require the low-temperature superconducting environment required for some quantum measurements, and the cost of environmental construction is very low. Liquid core optical fiber is used to perform the first-level homogenization of the laser, and then the laser can be homogenized when entering the optical system, avoiding the laser energy loss caused by the general use of cutting and homogenization solutions, and ensuring the subsequent light power density of the diamond color center excitation. The incident lens group and the CCD front lens group adopt the method of a combined mirror box, which reduces the influence of external light on the optical path of the device, and the lens of the mirror box can be replaced, which is convenient for subsequent upgrades of the system and modifications according to different needs. The incident lens group uses the Köhler illumination system to convert the laser into a uniform light spot. The field diaphragm and aperture diaphragm used in this Köhler illumination system are both adjustable diaphragms, which can control the area of ​​the formed light spot, further control the number of excited color centers, and achieve adjustment of sensitivity and detection speed. The exit lens group can be installed with filters according to measurement requirements, which can significantly reduce the impact of stray light on the signal acquisition of the image receiving end of the device. Light attenuation plates can also be installed according to the light tolerance of different signal receivers (CCD cameras). The installation of the penetration group is carried out in the form of a lens group box, which greatly improves the optical stability and has a light-shielding effect, avoiding the influence of natural light on the light excitation and light collection of the device. The Köhler illumination system is used in conjunction with a large-area diamond sheet to achieve wide-field chip near-magnetic field rapid imaging. Compared with the general single-color center measurement solution, the detection speed is improved and dynamic magnetic field imaging of the chip can be achieved. Using an area array CCD camera instead of a traditional photon detector to collect near-magnetic field signals can achieve surface-by-surface near-magnetic field signal acquisition, and an algorithm can be used to calculate the positional relationship between the magnetic field image and the chip surface. The algorithm can also be used to analyze the magnetic field trend at a certain point or area. Using a computer and a delay device for combined control, a variety of dynamically decoupled measurement sequences can be achieved, and different measurement requirements can be adapted by changing the measurement method. Using an image processing image stitching algorithm, combined with a high-precision electrically controlled two-position translation stage, large-area chips are imaged by measuring and imaging in different areas and then stitching the images together to achieve rapid imaging of large-area chips, allowing visualization of the surface near-magnetic field of large-area chips.

[0125] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0126] This document uses specific examples to illustrate the principles and implementations of the present invention. The above examples are only intended to help understand the system and core concepts of the present invention. At the same time, those skilled in the art will appreciate that variations in the specific implementations and scope of application are possible based on the concepts of the present invention. In summary, this specification should not be construed as limiting the present invention.

Claims

1. A chip near-field magnetic field measurement system, characterized in that: It includes: laser emission modulation device, optical path adjustment module, diamond plate, electric-controlled two-dimensional translation stage, CCD camera and electromagnetic shielding control device; The laser emission modulation device is arranged on the first input optical path of the optical path adjustment module; the laser emission modulation device is used to output modulated laser light; The electrically controlled two-dimensional translation stage is disposed on the first output optical path and the second input optical path of the optical path adjustment module; the first output optical path and the second input optical path overlap, and the directions of optical signal transmission are opposite; the electrically controlled two-dimensional translation stage is used to carry the chip under test and adjust the measurement area of ​​the chip under test by horizontal sliding; The diamond plate is arranged between the electrically controlled two-dimensional translation stage and the optical path adjustment module; when the chip under test is powered on, the diamond plate is within the near-field magnetic field of the measurement area of ​​the chip under test; the measurement area is the projection area of ​​the diamond plate on the chip under test; The CCD camera is arranged on the second output light path of the light path adjustment module; The electromagnetic shielding control device is respectively connected to the electrically controlled two-dimensional translation stage, the laser emission modulation device, the diamond plate and the CCD camera; the electromagnetic shielding control device is used to control the horizontal sliding of the electrically controlled two-dimensional translation stage; the electromagnetic shielding control device is also used to emit quantum state control microwaves to perform quantum state microwave modulation on the diamond plate; The optical path adjustment module is configured to reflect the modulated laser light to the diamond sheet covering the chip under test; the optical path adjustment module is also configured to transmit a fluorescence signal to the CCD camera; the fluorescence signal is generated by the diamond sheet under the combined action of the modulated laser light, the quantum state control microwave, and the near-field magnetic field of the measurement area of ​​the chip under test; The electromagnetic shielding control device is further used to determine the near-field magnetic field distribution of the chip under test based on the fluorescence signals corresponding to different measurement areas on the chip under test.

2. A chip near-field magnetic field measurement system according to claim 1, characterized in that: The laser emission modulation device includes: a laser and an acousto-optic modulator; The laser and the acousto-optic modulator are both connected to the electromagnetic shielding control device; the laser and the acousto-optic modulator are connected through a liquid core optical fiber; the acousto-optic modulator is connected to the optical path adjustment module through an optical fiber; The laser is used to emit laser light; The liquid core optical fiber is used to homogenize the laser to obtain homogenized laser light; The acousto-optic modulator is used to modulate the homogenized laser light to obtain modulated laser light.

3. A chip near-field magnetic field measurement system according to claim 2, characterized in that: The chip near-field magnetic field measurement system further includes: a microwave antenna; The microwave antenna is connected to the diamond sheet; The microwave antenna is used to receive the quantum state control microwave.

4. A chip near-field magnetic field measurement system according to claim 3, characterized in that: The chip near-field magnetic field measurement system further includes: an optical plate and a pneumatic vibration isolation optical platform; The pneumatic vibration isolation optical platform is used to carry the optical flat plate, the laser, the electrically controlled two-dimensional translation stage and the electromagnetic shielding control device; The optical plate is arranged perpendicular to the pneumatic vibration isolation optical platform; the optical plate is used to carry the acousto-optic modulator, the optical path adjustment module, the diamond plate, the microwave antenna and the CCD camera.

5. A chip near-field magnetic field measurement system according to claim 4, characterized in that: The electromagnetic shielding control device includes: a computer, an image acquisition card and a microwave control module; The image acquisition card is connected to the CCD camera; the image acquisition card is used to acquire fluorescence signal images corresponding to different measurement areas on the chip under test; The microwave control module is connected to the acousto-optic modulator and the microwave antenna respectively; The computer is respectively connected to the image acquisition card, the microwave control module, the laser and the electrically controlled two-dimensional translation stage; the computer is used to control the laser to emit laser light; the computer is also used to control the microwave control module to modulate the laser light after homogenization to obtain modulated laser light; the computer is also used to control the microwave control module to emit quantum state control microwaves to perform quantum state microwave modulation on the diamond sheet; the computer is also used to determine the near-field magnetic field distribution of the chip under test based on the fluorescence signal images corresponding to different measurement areas on the chip under test.

6. A chip near-field magnetic field measurement system according to claim 5, characterized in that: The microwave control module includes: a power amplifier, a microwave generator and a delay device; The time delay device is connected to the AOM, the microwave generator and the computer respectively; the time delay device is arranged on the pneumatic vibration isolation optical platform; the time delay device is used to generate a clock signal; the computer is used to control the AOM according to the clock signal; The microwave generator is further connected to the power amplifier and the computer respectively; the computer is further used to control the microwave generator to emit quantum state control microwaves according to the clock signal; The power amplifier is arranged in the microwave system box; the power amplifier is also connected to the microwave antenna; the power amplifier is used to perform power amplification processing on the quantum state control microwave.

7. A chip near-field magnetic field measurement system according to claim 6, characterized in that: The electromagnetic shielding control device further includes: an electromagnetic shielding storage box; The electromagnetic shielding storage box is arranged on the pneumatic vibration isolation optical platform; a plurality of electromagnetic shielding storage compartments are arranged in the electromagnetic shielding storage box; the image acquisition card, the microwave system box and the microwave generator are respectively arranged in different electromagnetic shielding storage compartments.

8. A chip near-field magnetic field measurement system according to claim 4, characterized in that: The optical path adjustment module includes: an incident light lens assembly box, a dichroic mirror, a CCD front lens assembly box and a lens assembly light shielding box; The lens assembly light-shielding box is arranged on the optical plate; The dichroic mirror is arranged in the lens group light-shielding box; the lens group light-shielding box is provided with a first mounting hole, a second mounting hole and a light-through hole; the first mounting hole is arranged on the first input light path of the dichroic mirror; the light-through hole is arranged on the first output light path and the second input light path of the dichroic mirror; the first output light path and the second input light path coincide with each other and the directions of light signal transmission are opposite; the second mounting hole is arranged on the second output light path of the dichroic mirror; The incident light lens assembly is arranged at the first mounting hole; the incident light lens assembly is connected to the acousto-optic modulator; the incident light lens assembly is used to modulate the modulated laser into a laser spot; The CCD front lens assembly box is arranged at the second mounting hole; the CCD front lens assembly box is arranged on the input light path of the CCD camera.

9. A chip near-field magnetic field measurement system according to claim 8, characterized in that: The incident light lens assembly box comprises: a light shielding shell and a light collecting mirror, a field stop, an aperture stop and a condenser lens arranged in sequence in the light shielding shell; The light-shielding housing is connected to the acousto-optic modulator.

10. A chip near-field magnetic field measurement system according to claim 4, characterized in that: The chip near-field magnetic field measurement system further includes: a fixture; The clamp is rotatably arranged on the optical plate; the clamp is used to fix the diamond plate and adjust the angle of the diamond plate.

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