An imaging device and method based on diamond nv color centers

Abstract

The application provides a diamond NV color center-based imaging device and method, wherein the imaging device comprises a diamond containing NV color centers, an objective assembly, an optical detection module, a displacement platform, a microwave module; the objective assembly comprises an objective turntable, an objective and a suction tube mounted on the objective turntable, the objective turntable can switch the objective or the suction tube to a working position, and the suction tube is used for passing in negative pressure; the displacement platform is located below the objective assembly, the upper surface of the displacement platform is used for placing a to-be-detected member, and the position of the to-be-detected member can be adjusted; the diamond is used for being placed on the to-be-detected member and located below the working position of the objective assembly, when the suction tube is switched to the working position, the lower end opening of the suction tube is opposite to the diamond, and the diamond can be adsorbed or released by controlling the negative pressure in the tube. The implementation is simple, the use of other auxiliary equipment is reduced, the occupied space is simplified, and accurate and efficient operation of the adsorption and release of the diamond can be ensured. The device can realize multiple imaging scanning of a large-size to-be-detected member.

Description

Technical Field

[0001] This invention relates to the field of quantum sensing, and in particular to an imaging device and method based on diamond NV color centers. Background Technology

[0002] With the rapid development of quantum precision measurement technology, precision sensing and detection technology based on nitrogen-vacancy (NV) color centers in diamond has been widely applied. Wide-field imaging using NV color centers can be applied to the measurement of magnetic field distributions over a wide range, offering advantages such as high resolution and high accuracy, and has great potential in the field of chip inspection.

[0003] In practical applications, to obtain better measurement sensitivity, diamond is generally placed directly on the sample under test, such as the upper surface of a chip. Since the size of the chip being tested is generally larger than the size of the diamond, a single measurement cannot achieve full coverage of the chip; therefore, multi-area measurement is required on the chip surface. This necessitates adjusting the position of the diamond relative to the chip surface. Because the imaging device needs to remain stable, the diamond and chip must be separated to allow for chip position adjustment. After the chip is moved to the new position, the diamond is placed back in its original position. While adjusting the chip position can be achieved by manually picking up and placing the diamond before and after chip movement, manual diamond picking is obviously prone to errors and inefficiency. Furthermore, adding high-precision picking and placing equipment to the imaging device presents space constraints, hindering miniaturization. Therefore, how to accurately and efficiently pick up and place the diamond on the test piece while saving space is a problem that needs to be solved. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide an imaging device and method based on diamond NV centers, which solves the problems of large errors and low efficiency in wide-field imaging based on diamond NV centers, where diamonds are manually picked up and placed on the test piece, and the problem that adding high-precision picking and placing equipment to the imaging device also results in insufficient space and is not conducive to miniaturization design.

[0005] To achieve the above and other related objectives, a first aspect of the present invention provides an imaging device based on diamond NV centers, comprising: a diamond containing NV centers, an objective lens assembly, an optical detection module, a displacement platform, and a microwave module;

[0006] The objective lens assembly includes an objective lens turret and an objective lens and a pipette mounted on it. The objective lens turret can switch the objective lens or the pipette to the working position, and the pipette is used to introduce negative pressure.

[0007] The displacement platform is located below the objective lens assembly. Its upper surface is used to place the test piece and the position of the test piece can be adjusted.

[0008] The diamond is placed on the test piece and is located below the working position of the objective lens assembly. When the pipette is switched to the working position, the lower opening of the pipette faces the diamond, and the diamond can be adsorbed or released by manipulating the negative pressure inside the pipette.

[0009] The optical detection module is used to irradiate the objective lens located in the working position with excitation light. The excitation light is transmitted through the objective lens and then irradiates the diamond located below it to excite fluorescence. It is also used to collect this fluorescence through the objective lens for imaging and output imaging data.

[0010] The microwave module is used to radiate microwaves onto the diamond.

[0011] Furthermore, the objective lens assembly also includes a negative pressure device for providing negative pressure into the pipette.

[0012] Furthermore, the upper ends of both the objective lens and the pipette are fixedly mounted on the rotating disk of the objective lens turret, and the objective lens or pipette can be switched to the working position by rotating the rotating disk.

[0013] Furthermore, the side wall of the straw is provided with a hollow connector that communicates with the lumen of the straw for connecting to negative pressure.

[0014] Furthermore, the lower end of the straw is made of flexible material, with a diameter of 1mm-2mm at the lower end.

[0015] Furthermore, the optical detection module includes an excitation light source, a dichroic filter, and an imaging module. The excitation light source is used to generate excitation light and illuminate the dichroic filter. After being reflected by the dichroic filter, the light is transmitted through the objective lens located in the working position and then illuminates the diamond. The fluorescence generated by the diamond is transmitted through the objective lens and the dichroic filter in sequence and then enters the imaging module to be collected and imaged.

[0016] Furthermore, the microwave module includes a microwave source and a microwave antenna. The microwave source transmits microwaves to the microwave antenna, and the microwave antenna is used to radiate microwaves to the diamond. The microwave antenna is a microstrip antenna with a through hole at its radiating end, facing the objective lens located in the working position. The diamond is located below or inside the through hole.

[0017] Furthermore, it also includes a bias magnetic field module for applying a bias magnetic field to the diamond.

[0018] To achieve the above and other related objectives, a second aspect of the present invention provides an imaging scanning method based on diamond NV centers, implemented using an imaging apparatus based on diamond NV centers as described in any one of the first aspects, comprising:

[0019] When it is necessary to change the detection area of ​​the test piece, perform the following steps: Stop the imaging detection operation; switch the pipette to the working position, adjust the height of the displacement platform so that the lower end of the pipette contacts the upper surface of the diamond, manipulate the negative pressure in the pipette to adsorb and hold the diamond; adjust the displacement platform so that the test piece is at the new predetermined horizontal position, manipulate the negative pressure in the pipette to release the diamond to the upper surface of the test piece, adjust the height of the displacement platform so that the diamond is in the initial position, and start the imaging detection operation.

[0020] To achieve the above and other related objectives, a third aspect of the present invention provides a non-destructive testing method based on diamond NV color centers, comprising: performing a low-magnification objective lens imaging scan on the entire test piece using the imaging scanning method described in the second aspect; combining the magnetic field intensity distribution maps of all detection areas obtained by the scan into a single image; analyzing and determining whether the test piece has defects; if defects exist, taking the area where the defects are located as the target area for further detection; and then performing a high-magnification objective lens imaging scan on the target area using the imaging scanning method described in the second aspect to obtain the magnetic field intensity distribution of the target area, thereby obtaining the distribution of defects.

[0021] As described above, the imaging device and method based on diamond NV centers of the present invention have the following beneficial effects: By mounting an objective lens and a pipette for adsorbing or releasing diamond on an objective lens turret, and switching the objective lens or pipette to the working position through the rotation function of the objective lens turret, the precise and fixed positional relationship between the working position of the objective lens turret and the diamond is utilized. Through switching, the dual functions of diamond adsorption / release and objective lens imaging are achieved. This method is simple to implement, reduces the use of other auxiliary equipment, and the precise microscopic positioning ensures accurate and efficient operation of diamond adsorption and release when the pipette is rotated to the working position. Using this device, the detection area of ​​a large-sized test piece can be changed when adsorbing diamond, realizing imaging scanning of different detection areas, and it can be used in non-destructive testing. Attached Figure Description

[0022] Figure 1 The diagram shows the structure of the imaging device.

[0023] Figure 2 The diagram shows the structure of the objective lens assembly.

[0024] Figure 3 The diagram shows the structure of the optical detection module.

[0025] Figure 4 The diagram shown is an exemplary structural diagram of the bottom surface of a microwave antenna;

[0026] Figure 5 The diagram shown is an exemplary top view of a microwave antenna.

[0027] Component labeling: 1—Diamond; 2—Objective lens assembly; 21—Objective turret; 211—Rotating disk; 212—Fixed disk; 213—Interface; 22—Objective lens; 23—Pipe; 231—Hollow connector; 24—Negative pressure device; 241—Negative pressure source; 242—Negative pressure delivery tube; 3—Optical inspection module; 31—Excitation source; 32—Condenser lens; 33—Dichroic filter; 34—Imaging module; 341—Filter; 342 —Imaging lens; 343—Imaging camera; 4—Displacement platform; 5—Microwave module; 51—Microwave source; 52—Microwave antenna; 521—Through hole; 522—Radiating patch; 523—Microstrip line; 524—Grounding patch; 525—Metallized hole; 53—Control platform; 6—DUT; 7—Magnet; 8—Threaded connector; 81—Fixing ring; 82—Fixing rod; 9—Eye tube; 10—Control module; 20—Data processing module. Detailed Implementation

[0028] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0029] It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0030] Example 1: As Figure 1 As shown, this embodiment provides an imaging device based on diamond NV color centers, including a diamond 1 containing NV color centers, an objective lens assembly 2, an optical detection module 3, a displacement platform 4, and a microwave module 5;

[0031] Objective lens assembly 2 includes objective lens turret 21 and objective lens 22 and pipette 23 mounted thereon. Objective lens turret 21 can switch objective lens 22 or pipette 23 to working position. Negative pressure is introduced into pipette 23.

[0032] The displacement platform 4 is located below the objective lens assembly 2. Its upper surface is used to place the test piece 6 and the position of the test piece 6 can be adjusted.

[0033] Diamond 1 is placed on the test piece 6 and is located below the working position of the objective lens assembly 2. When the pipette 23 is switched to the working position, the lower opening of the pipette 23 faces the diamond 1, and the diamond 1 can be adsorbed or released by controlling the negative pressure inside the pipette.

[0034] The optical detection module 3 is used to irradiate the excitation light onto the objective lens 22 located in the working position. The excitation light is transmitted through the objective lens 22 and then irradiates the diamond 1 located below it to excite fluorescence. It is also used to collect this fluorescence through the objective lens 22 for imaging and output imaging data.

[0035] Microwave module 5 is used to radiate microwaves to diamond 1.

[0036] In this embodiment, an objective lens and a pipette for adsorbing or releasing diamonds are mounted on an objective lens turret. The objective lens or pipette is switched to the working position by rotating the objective lens turret. Simply rotating the objective lens turret positions the pipette in the working position. Since the working position of the objective lens turret and the diamond are relatively fixed, the lower end of the pipette can be aligned with the diamond on the test piece. Adsorption and release of the diamond below can be achieved by manipulating the pipette with negative pressure. This method is simple and utilizes an existing objective lens turret for imaging, achieving both objective lens optical imaging and diamond handling. This reduces the need for other auxiliary equipment, simplifies space occupation, and ensures precise and efficient diamond adsorption and release when the pipette is rotated to the working position. The working position referred to in this embodiment is the position where the objective lens is rotated until its optical axis is aligned with the optical axis of the imaging optical path.

[0037] Objective turrets are commonly used optical devices in microscopic imaging, such as... Figure 2 As shown, it is equipped with a rotating disk 211 and a fixed disk 212, and the fixed disk 212 is equipped with mounting devices such as... Figure 1 The interface 213 of the lens barrel 9 aligns the optical axis of the objective lens 22 with the optical axis of the lens barrel 9 after the objective lens 22 is rotated to the working position. The optical path in the lens barrel 9 is part of the imaging optical path. The objective lens turret 21 can be rotated manually or automatically. When the automatic mode is selected, the automation level of the objective lens assembly can be further improved.

[0038] like Figure 2 As shown, the upper ends of the objective lens 22 and the pipette 23 are fixedly mounted on the rotating disk 211 of the objective lens turret 21. By rotating the rotating disk 211, the objective lens 22 or the pipette 23 is rotated to the same working position. The fixed position of the same working position relative to the diamond is used to achieve precise adsorption and release of the diamond, and the position can be kept unchanged after release.

[0039] The objective lens 22 and the pipette 23 are mounted on the rotating disk 211 using the existing mounting holes on the disk. These mounting holes are symmetrically distributed around the rotation axis of the disk, allowing any one of the mounting holes to be switched to the same working position by rotating around the axis. The objective lens 22 and the pipette 23 are mounted one-to-one in multiple mounting holes. The optical axis of the objective lens and the central axis of the pipette are coaxial with the central axis of the mounting hole. Thus, when the objective lens is in the working position, the diamond is located below the objective lens. When the pipette is switched to the working position, the diamond is located below the pipette, so that the lower end of the pipette faces the diamond.

[0040] The mounting hole is generally threaded, and the upper end of the objective lens 22 is installed in the mounting hole via an external thread. The upper end of the suction tube 23 can be exemplarily shown as follows: Figure 2 The device is connected to the mounting hole via a threaded connector 8. The threaded connector 8 includes a retaining ring 81 with threads on both its inner and outer sides, and a retaining rod 82 with threads on its upper and lower outer sides. The threads on the outer side of the retaining ring 81 connect to the internal threads of the mounting hole in the rotating disk 211, and the threads on its inner side connect to the external threads at the upper end of the retaining rod 82. The upper end of the straw 23 is open, and the inner side of the opening is threaded to connect to the external threads at the lower end of the retaining rod 82. The upper opening of the straw 23 is not connected to the straw cavity and is only used for installation. Other installation structures can also be used.

[0041] like Figure 2 As shown, the objective lens assembly 2 also includes a negative pressure device 24 for providing negative pressure into the pipette 23. The negative pressure device 24 includes a negative pressure source 241 and a negative pressure delivery tube 242. One end of the negative pressure delivery tube 242 is connected to the side wall of the pipette 23, and the other end is connected to the negative pressure source 241. The side wall of the pipette 23 is provided with a hollow connector 231 communicating with the lumen of the pipette 23, for connecting to the negative pressure device 24 and receiving negative pressure from the negative pressure device 24. Figure 2 As shown, one end of the negative pressure delivery pipe 242 is connected to the hollow connector 231 on the side wall of the suction pipe 23 to deliver negative pressure into the suction pipe 23. The negative pressure source 241 can be a vacuum device, such as a vacuum pump, to generate negative pressure. The negative pressure delivery pipe 242 is made of a soft material, such as rubber, to facilitate the arrangement of the pipeline.

[0042] To ensure precise adsorption of diamond 1 via negative pressure, the lower end of the suction tube 23 is made of a flexible material, such as rubber or flexible plastic. This buffers the adsorption force applied to the diamond during negative pressure adsorption, preventing the diamond from shifting or failing to adsorb due to rigid adsorption force when the bottom of the suction tube contacts the diamond. The diameter of the lower end of the suction tube is 1mm-2mm to accommodate wide-field imaging based on diamond NV color centers. The size of the diamond used for wide-field imaging is several millimeters, for example, 2mm-5mm. Figure 1The straw 23 in the example is tapered at the bottom, but it can also be a straight straw or other types of straw.

[0043] When the suction tube 23 is in the working position, the distance between the bottom end of the suction tube 23 and the upper surface of the diamond is 1-2 mm, leaving sufficient space for switching suction tubes. When adsorbing the diamond, the height of the displacement platform 4 needs to be adjusted to ensure that the upper surface of the diamond 1 is attached to the lower end of the suction tube 23, with the two fitting as seamlessly as possible to ensure adsorption force and prevent movement of the diamond 1 during adsorption. After adsorption, keeping the diamond 1 stationary, the height of the displacement platform 4 can be readjusted to separate the test piece 6 from the diamond 1, facilitating the adjustment of the horizontal position of the test piece 6. After the horizontal position of the test piece 6 is adjusted, the displacement platform 4 is adjusted again until the test piece 6 and the diamond 1 are attached again, and the diamond 1 is released by manipulating the suction tube 23. Finally, the displacement platform 4 is adjusted back to its original height, thus completing one image position adjustment of the test piece 6.

[0044] In this embodiment, there can be one or more objectives, depending on the needs. For example, multiple objectives with different magnifications can be set to achieve different imaging requirements.

[0045] Optical detection module 3, such as Figure 3 As shown, the exemplary embodiment includes an excitation light source 31, a condenser lens 32, a dichroic filter 33, and an imaging module 34. The excitation light source 31 is used to generate excitation light, which is a laser in this case. The laser light is focused by the condenser lens 32 and transmitted to the dichroic filter 33. After being reflected by the dichroic filter 33, it is transmitted through the objective lens 22 located in the working position and then illuminates the diamond 1. The fluorescence generated by the diamond 1 is transmitted sequentially through the objective lens 22 and the dichroic filter 33 and then enters the imaging module 34 to be collected and imaged. Figure 3 Only one objective lens is shown as an example, and the structure of the objective lens turntable is not fully shown. The imaging module 34 includes a filter 341, an imaging lens 342, and an imaging camera 343. The fluorescence transmitted through the dichroic filter 33 is filtered out by the filter 341, converged by the imaging lens 342, and finally collected by the imaging camera 343. The optical route from the objective lens 22 to the optical detection module 3 is as follows: Figure 1 The transmission is carried out through the lens tube 9.

[0046] The microwave module 5 includes a microwave source 51 and a microwave antenna 52. The microwave source 51 transmits microwaves to the microwave antenna 52. The microwave antenna 52 is close to the diamond 1 and is used to radiate microwaves to the diamond 1. The microwave antenna 52 is located on one side of the diamond 1, such as the upper or lower side or the circumferential side, or the diamond is housed in the antenna. Various types of antennas can be used for the microwave antenna, as long as they can radiate microwaves to the diamond. In this embodiment, a microstrip antenna is used, with a through-hole 521 opened at its radiating end, facing the objective lens 22 located in the working position. The diamond 1 is placed inside the through-hole 521 or... Figure 1 , Figure 3 Below the through-hole 521 shown; when it is necessary to use the suction tube 23 to adsorb diamond 1, if diamond 1 is located below the through-hole 521, the radiating end of the microwave antenna 52 must be moved away from above diamond 1 before the adsorption and release operation is performed. If diamond 1 is located in the through-hole 521, since the diameter of the through-hole 521 is larger than the maximum side length of the diamond, the adsorption and release operation can be performed directly. The microwave source 51 is not limited to the generation of microwave signals; it may also include microwave signal processing as needed, such as amplification and isolation of reflected signals.

[0047] like Figure 1 As shown, a control platform 53 is also provided for mounting the microwave antenna 52. The radiating end of the microwave antenna 52 can be moved away from above the diamond 1 by rotating the control platform 53. One end of the microwave antenna 52 is the radiating end, suspended above the diamond 1, with the radiating surface located on the bottom surface of the antenna and facing the diamond 1. The other end is the feed end, fixedly mounted on the control platform 53. Rotating the control platform 53 moves the radiating end away from above the diamond 1. After the diamond's absorption and release operations are completed, rotating the control platform 53 again moves the radiating end back above the diamond 1. The displacement platform 4 and the control platform 53 can be multi-dimensional precision adjustment devices, which, in addition to angle adjustment, also have three-dimensional coordinate direction displacement adjustment functions. After the position is adjusted, it can automatically lock the position to achieve precise positioning. The adjustment accuracy can be selected according to needs; the three-dimensional axial accuracy can be 10 micrometers, and the angle accuracy can be 0.01 degrees. Manual adjustment is possible; preferably, in this embodiment, the angle of each rotation and / or the three-axis displacement are automatically controlled by a program and coordinated with the diamond pick-up and release operation to achieve fully automated operation, which improves both efficiency and accuracy.

[0048] This embodiment uses a microstrip antenna, as exemplified by... Figure 4 As shown, a radiation patch 522 is provided on the bottom surface of the radiation end, facing the diamond, to provide relatively uniform microwave radiation to the diamond in the imaging direction, and the through-hole 521 at the radiation end can also provide the imaging field of view. In this embodiment, the radiation patch 522 is an open ring structure distributed circumferentially along the through-hole 521 to be suitable for wide-field imaging of the NV color center, and adopts a double-ring structure, that is, an inner ring extends outward from the opening to increase the bandwidth.

[0049] The radiating patch 522 is connected to the feed end via a microstrip line 523. The end of the microstrip line 523 at the feed end is connected to a metallized via 525, which connects to the signal pin of the microwave connector located on the top surface of the feed end to achieve microwave signal transmission. A grounding patch can also be provided on the top surface of the feed end and connected to the grounding pin of the microwave connector. For example, an IPEX first-generation microwave connector can be used. Figure 5As shown, two grounding patches 524 are disposed on the top surface of the feed end, which are respectively connected to the two grounding pins of the microwave connector. The center signal pin of the microwave connector is connected to the microstrip line 523 through the central metallized hole 525. Both the patches and the microstrip line can be formed by copper pouring. The specific parameters of the antenna structure are designed according to the application requirements.

[0050] For microstrip antenna installation, mounting holes can be provided on both the portion of the microstrip antenna located on the control platform and the mounting area of ​​the control platform, and then fixed with screws. Alternatively, a mounting block with a receiving slot can be used, which is fixedly connected to the control platform through mounting holes, with the microstrip antenna passing through the receiving slot for fixation. All of these installation methods must have their impact on the antenna's radiation performance considered during antenna design to create an antenna that meets the requirements.

[0051] This embodiment may also include, for example Figure 1 , Figure 3 As shown, the system includes a bias magnetic field module for applying a bias magnetic field to the diamond to adjust the resonance peak generated by the color center, or to ensure that the detection of weak magnetic fields by the color center operates in the linear region, or to adjust the detection frequency band to improve the sensitivity of weak magnetic field detection. The bias magnetic field module exemplarily includes a Helmholtz coil or, for example... Figure 1 , Figure 3 When using a Helmholtz coil, the objective lens assembly, diamond, and displacement platform are all placed within the coil frame to ensure sufficient operating space between the diamond, the objective lens, and the test piece. When using a magnet, a permanent magnet or a passable electromagnet can be selected.

[0052] For a heavier diamond 1, releasing the negative pressure within the suction tube 23 allows it to quickly fall onto the surface of the test piece under gravity. However, for a lighter diamond 1, after releasing the negative pressure, electrostatic and van der Waals forces exist between the lower end of the suction tube 23 and the surface of the diamond 1, preventing release due to gravity. In this case, a suitable amount of positive pressure can be introduced into the suction tube 23 by manipulating the negative pressure source 241 to assist in the release of the diamond. The negative and positive pressure values ​​used are determined experimentally to ensure rapid and reliable adsorption and release when the lower end of the suction tube is in contact with the diamond surface. Alternatively, the bottom of the suction tube 23 can be designed to eliminate static electricity, such as using an anti-static material.

[0053] This embodiment also includes a control module 10 and a data processing module 20. The control module 10 controls the rotation of the objective lens turret 2 to switch between the objective lens 22 and the pipette 23, and controls the angle or displacement adjustment of the displacement platform 4 and the adjustment platform 53. Of course, in the case of manual control, the control module 10 can be omitted. The data processing module 20 receives the imaging data output by the optical detection module 3 and processes and analyzes the imaging data, such as calculating the magnetic field strength and forming a magnetic field strength distribution map. The imaging data includes at least the grayscale value of each pixel.

[0054] Example 2: This example provides an imaging scanning method based on diamond NV centers, using the imaging device based on diamond NV centers from Example 1, including:

[0055] When it is necessary to change the detection area of ​​the test piece, perform the following steps: stop the imaging detection operation; switch the suction tube 23 to the working position, adjust the height of the displacement platform 4 so that the lower end of the suction tube 23 contacts the upper surface of the diamond 1, manipulate the negative pressure in the suction tube 23 to adsorb and hold the diamond 1; adjust the displacement platform 4 so that the test piece is at a new predetermined horizontal position, manipulate the negative pressure in the suction tube 23 to release the diamond 1 to the upper surface of the test piece, adjust the height of the displacement platform 4 so that the diamond 1 is in the initial position, and start the imaging detection operation.

[0056] This embodiment employs the imaging device described in Embodiment 1. It utilizes the precise and fixed positional relationship between the working position of the objective lens turret and the diamond, and through switching, achieves the dual functions of diamond pickup and loading as well as objective lens imaging. Ultimately, it enables multiple scanning imaging of test pieces larger than the diamond's imaging field of view. The entire operation can be automated, greatly improving work efficiency.

[0057] The process of adjusting the displacement platform 4 to bring the test piece 6 to a new predetermined horizontal position includes the following steps: lowering the height of the displacement platform 4 to separate the test piece 6 from the diamond 1; adjusting the horizontal position of the displacement platform 4 so that the new test area on the test piece 6 corresponds longitudinally to the diamond 1; and raising the height of the displacement platform 4 until the diamond 1 is in contact with the upper surface of the test piece 6.

[0058] The imaging detection operation includes turning on the microwave module 5 to radiate microwaves to the diamond, and starting the optical detection module 3 to perform imaging detection.

[0059] Before starting the imaging test for the first time, preparations need to be made, including configuring the following positional relationships: the objective lens 22 with the required magnification is in the working position; the test piece 6 is placed on the displacement platform 4, and the diamond 1 is placed on the test area on the upper surface of the test piece 6, facing the objective lens 22 in the working position, and within the radiation area of ​​the microwave module 5.

[0060] When using the microwave antenna 52 in Embodiment 1 to radiate microwaves to the diamond 1, the diamond 1 is positioned within the radiation area of ​​the microwave module 5 during preparation. Specifically, the diamond 1 is positioned inside or below the through-hole 521 of the microwave antenna 52. For the case where the diamond 1 is located within the through-hole 521, during preparation, the radiating end of the microwave antenna 52 is first placed above the area to be tested on the device under test 6, and then the diamond 1 is placed in the through-hole 521, positioned on the area to be tested on the device under test 6. The distance between the objective lens 22 and the diamond 1 is determined based on the working distance of the objective lens 22, and the distance between the microwave antenna 52 and the diamond 1 is determined experimentally, with the optimal effect of the diamond receiving microwave radiation being taken into account.

[0061] When diamond 1 is located below through-hole 521, since the working position of objective lens turret 21 is fixed after installation, the precise positions of objective lens 22, microwave antenna 52, and diamond 1 can be determined. During preparation, the order of placement of objective lens 22, microwave antenna 52, and diamond 1 is not important; they can be placed according to the precisely calculated positions. Before or after switching the suction tube 23 to the working position, the radiating end of microwave antenna 52 is moved away from above diamond 1 to facilitate the suction and release operation of diamond 1. After releasing diamond 1 onto the upper surface of the test piece 6, the height of the displacement platform 4 is adjusted so that diamond 1 is in its initial position, and then the radiating end of microwave antenna 52 is moved back above diamond 1.

[0062] For scanning the detection area of ​​the test piece, the coordinate method can be used to record and move the detection area for each scan, or the scanning step method can be used to represent the detection area after each move by the step of movement.

[0063] The scanning method of this embodiment can be used in non-destructive testing to detect defects, such as those on the surface of a chip. The specific method is as follows: First, the entire device under test is scanned under a low-magnification objective lens using the aforementioned imaging scanning method. The magnetic field intensity distribution maps of all the detection areas obtained by the scan are collected into one image. The analysis is used to determine whether there are defects in the device under test. If there are defects, the area where the defects are located is taken as the target area for further detection. Then, a high-magnification objective lens imaging scan is performed on the target area using the aforementioned imaging scanning method to obtain the magnetic field intensity distribution of the target area, thereby obtaining the distribution of defects.

[0064] Low-magnification objectives typically use 5x, 10x, or other magnifications, while high-magnification objectives include 20x, etc. The terms "high" and "low" refer to the comparison between the magnifications used in the two scans. Low-magnification imaging is performed first because it provides a larger field of view, reducing the number of scans and improving efficiency. This allows for faster imaging and assessment of the entire area under test. If defects are found, a high-magnification scan is then performed on the defect area. This provides a higher signal-to-noise ratio, resulting in more detailed defect distribution information, and because the defect area is smaller, it further improves scanning efficiency.

[0065] Defects are identified based on the distribution of magnetic field strength. For example, if the magnetic field strength in a certain area is abnormal, exceeding or falling below the normal value, it indicates the presence of a defect. The data processing module 20 handles all aspects of this process, including ODMR spectral plotting, magnetic field calculation, formation of magnetic field strength distribution maps, and defect identification.

[0066] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can 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 those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An imaging device based on diamond NV color centers, characterized in that, The imaging device includes: a diamond containing NV color centers, an objective lens assembly, an optical detection module, a displacement platform, and a microwave module; The objective lens assembly includes an objective lens turret and an objective lens and a pipette mounted on it. The objective lens turret can switch the objective lens or the pipette to the working position, and the pipette is used to introduce negative pressure. The displacement platform is located below the objective lens assembly. Its upper surface is used to place the test piece and the position of the test piece can be adjusted. The diamond is placed on the test piece and is located below the working position of the objective lens assembly. When the pipette is switched to the working position, the lower opening of the pipette faces the diamond, and the diamond can be adsorbed or released by manipulating the negative pressure inside the pipette. The optical detection module is used to irradiate the objective lens located in the working position with excitation light. The excitation light is transmitted through the objective lens and then irradiates the diamond located below it to excite fluorescence. It is also used to collect this fluorescence through the objective lens for imaging and output imaging data. The microwave module is used to radiate microwaves onto the diamond.

2. The imaging device based on diamond NV color centers according to claim 1, characterized in that: The objective lens assembly also includes a negative pressure device for providing negative pressure into the pipette.

3. The imaging device based on diamond NV color centers according to claim 1 or 2, characterized in that: The upper ends of the objective lens and the pipette are fixedly mounted on the rotating disk of the objective lens turret, and the objective lens or pipette can be switched to the working position by rotating the rotating disk.

4. The imaging device based on diamond NV color centers according to claim 3, characterized in that: The straw has a hollow connector on its side wall that communicates with the straw's lumen for connecting to negative pressure.

5. The imaging device based on diamond NV color centers according to claim 1, characterized in that: The lower end of the straw is made of flexible material, with a diameter of 1mm-2mm.

6. The imaging device based on diamond NV color centers according to claim 1, characterized in that: The optical detection module includes an excitation light source, a dichroic filter, and an imaging module. The excitation light source generates excitation light and illuminates the dichroic filter. After being reflected by the dichroic filter, the light is transmitted through the objective lens located in the working position and then illuminates the diamond. The fluorescence generated by the diamond is transmitted through the objective lens and the dichroic filter in sequence and then enters the imaging module to be collected and imaged.

7. The imaging device based on diamond NV color centers according to claim 1, characterized in that: The microwave module includes a microwave source and a microwave antenna. The microwave source transmits microwaves to the microwave antenna, and the microwave antenna is used to radiate microwaves to the diamond. The microwave antenna is a microstrip antenna with a through hole at its radiating end, facing the objective lens located in the working position. The diamond is located below or inside the through hole.

8. The imaging device based on diamond NV color centers according to claim 1, characterized in that: It also includes a bias magnetic field module for applying a bias magnetic field to the diamond.

9. An imaging scanning method based on diamond NV color centers, characterized in that, The imaging method is implemented using an imaging apparatus based on diamond NV color centers as described in any one of claims 1-8, and includes: When it is necessary to change the detection area of ​​the test piece, perform the following steps: Stop the imaging detection operation; switch the pipette to the working position, adjust the height of the displacement platform so that the lower end of the pipette contacts the upper surface of the diamond, manipulate the negative pressure in the pipette to adsorb and hold the diamond; adjust the displacement platform so that the test piece is at the new predetermined horizontal position, manipulate the negative pressure in the pipette to release the diamond to the upper surface of the test piece, adjust the height of the displacement platform so that the diamond is in the initial position, and start the imaging detection operation.

10. A non-destructive testing method based on diamond NV color centers, characterized in that, The method includes: performing a low-magnification objective lens imaging scan on the entire test piece using the imaging scanning method as described in claim 9; combining the magnetic field intensity distribution maps of all detection areas obtained from the scan into a single image; analyzing and determining whether there are defects in the test piece; if defects exist, taking the area where the defects are located as the target area for further detection; and then performing a high-magnification objective lens imaging scan on the target area using the imaging scanning method as described in claim 9 to obtain the magnetic field intensity distribution of the target area, thereby obtaining the distribution of defects.

Images