Two-dimensional material heterojunction surface cleaning instrument

Abstract

The invention discloses a two-dimensional material heterojunction surface cleaning instrument, which comprises a driving control unit, a detection feedback system, a data acquisition card, a motion control card, a stepping motor, a cleaning head, a motor, a detection feedback system, a data processing unit, a data processing unit, a data processing unit, a data processing unit, a data processing unit, a data processing unit and a data processing unit, wherein the data acquisition card, the motion control card, the stepping motor, the cleaning head and the motor are integrated in the driving control unit; the force detection unit is electrically connected with the driving control unit and obtains a force signal in a mode of detecting the force borne by the cleaning head, and the sample table is used for fixing a two-dimensional material sample; the cleaning head is converted into the actuator from a traditional sensor and directly participates in pollutant removal instead of being only used for observation, mechanical damage is reduced, the cleaning efficiency and effect are improved, the material performance is improved, and chemical pollution is avoided.

Description

Technical Field

[0001] The present invention relates to a surface cleaner, and in particular to a surface cleaner for two-dimensional material heterojunctions. Background Art

[0002] Due to their unique electronic, optical, and mechanical properties, two-dimensional material heterojunctions have shown broad application prospects in fields such as semiconductor devices, optoelectronics, and sensors. However, the surfaces of these materials are vulnerable to contaminants (such as organic residues, particle adsorption, oxide layers, etc.), which may lead to a decline in interface quality, a reduction in carrier mobility, and instability in device performance.

[0003] Regarding the cleaning problem of two-dimensional material heterojunctions, the common methods and their limitations are as follows:

[0004] Chemical cleaning: Although solvents or acid solutions can remove contaminants, chemical substances may remain, damaging the lattice structure of the material.

[0005] Ion beam etching: Although the bombardment of high-energy ions can remove surface contaminants, it is prone to introducing defects and affecting the interface integrity of the heterojunction.

[0006] Mechanical peeling: It is only applicable to small-area cleaning, with low efficiency and difficulty in achieving uniform treatment.

[0007] Traditional plasma treatment: Using a single plasma source can lead to excessive etching or functionalization of the material surface.

[0008] Therefore, there is an urgent need to develop an efficient, non-destructive, and scalable surface cleaning technology to improve the interface quality and device performance of two-dimensional material heterojunctions. Summary of the Invention

[0009] In order to solve the deficiencies of the above technologies, the present invention provides a surface cleaner for two-dimensional material heterojunctions.

[0010] To solve the above technical problems, the technical solution adopted by the present invention is: A surface cleaner for two-dimensional material heterojunctions, comprising:

[0011] A drive control unit, which internally integrates a data acquisition card, a motion control card, and a stepper motor drive module;

[0012] A cleaning head, on whose cleaning surface a nano-spherical probe matrix is formed.

[0013] A motor, which is controlled by the stepper motor drive module of the drive control unit to displace the cleaning head in the vertical direction, and the vertical direction is the Z-axis;

[0014] The detection feedback system includes a capacitive pressure sensor installed between the motor and the cleaning head, and the acting force of the cleaning head is detected by the capacitive pressure sensor.

[0015] The sample stage fixes the two-dimensional material sample.

[0016] Furthermore, the nanosphere probe matrix of the cleaning head includes a number of nanosphere probes that work simultaneously.

[0017] Furthermore, the tip of the nanosphere probe is a spherical structure, and the surface roughness is ≤ 0.15 nm.

[0018] Furthermore, the motion control card of the drive control unit is connected to the stepper motor drive module, and the stepper motor drive module is connected to the motor.

[0019] Furthermore, a rotating shaft that provides a vertical displacement path for the cleaning head is arranged at the output end of the motor, and the cleaning head is implemented in a manner of approaching the two-dimensional material sample on the sample stage.

[0020] Furthermore, the capacitive pressure sensor of the detection feedback system follows the displacement of the cleaning head, and the acting force of the cleaning head detected by the capacitive pressure sensor is the interaction force generated when the cleaning head contacts the two-dimensional material sample.

[0021] Furthermore, the sample stage fastens the two-dimensional material sample through clip pieces.

[0022] Furthermore, the sample stage is implemented in a manner of displacing on the X-axis through an X-axis stepper motor, and the sample stage is implemented in a manner of displacing on the Y-axis through a Y-axis stepper motor.

[0023] A two-dimensional material heterojunction surface cleaner, which transforms the cleaning head from a traditional sensor into an actuator, directly participates in pollutant removal instead of only being used for observation, has the following advantages:

[0024] 1. Reducing mechanical damage: The ultrasmooth spherical tip of the nanosphere probe contacts the two-dimensional material surface more uniformly during the cleaning process compared with the traditional pyramid-shaped probe, greatly reducing the risk of mechanical damage to the material surface, effectively avoiding the generation of surface defects, protecting the lattice integrity of the material, and improving the material performance.

[0025] 2. Improving cleaning efficiency and effect: The larger contact area enables the nanosphere probe to act more effectively on the interlayer bubbles and pollutants with a smaller acting force, resulting in higher cleaning efficiency; at the same time, it can effectively remove the main bubbles and inclusions larger than 1 μm, and the cleaning effect is significantly better than the traditional method, improving the surface quality and consistency of the two-dimensional material; the cleaning head forms a probe matrix, and the cleaning efficiency is much higher than that of a single probe.

[0026] 3. Improve material properties: The two-dimensional material heterostructure treated by the nano-spherical probe, such as the MoS2 heterostructure, exhibits higher crystal quality, better photoluminescence effect, significantly reduced surface roughness, weakened phonon-electron scattering effect, extended exciton lifetime, and effectively improves the performance of the heterostructure device.

[0027] 4. Avoid chemical contamination: By adopting a physical cleaning method without the participation of chemical reagents, the introduction of chemical impurities is avoided, the intrinsic properties of the two-dimensional material are ensured, and the stability and reliability of the device are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a partial component composition diagram excerpted from the present invention.

[0029] Figure 2 It is a structural display diagram of the cleaning head of the present invention.

[0030] Figure 3 It is a schematic diagram of the driving control unit pattern of the present invention.

[0031] Figure 4 It is a display diagram of the sample stage and its connection of the present invention.

[0032] Figure 5 It is a structural display diagram of the cleaning head of the present invention.

[0033] Figure 6 It is an arrangement display diagram of the nano-spherical probe of the present invention.

[0034] Figure 7 It is an array pattern of the nano-spherical probe of the present invention.

[0035] Figure 8 It is a control diagram for the nano-spherical probe cleaning experiment.

[0036] In the figure:

[0037] 1. Driving control unit;

[0038] 2. Cleaning head; 20. Nano-spherical probe;

[0039] 3. Motor;

[0040] 4. Detection and feedback system;

[0041] 5. Sample stage;

[0042] 6. X-axis stepper motor;

[0043] 7. Y-axis stepper motor; DETAILED DESCRIPTION OF THE INVENTION

[0044] The present invention will be further described in detail below in conjunction with the drawings and specific embodiments.

[0045] As shown Figure 1-6 collectively, this embodiment relates to a surface cleaner for two-dimensional material heterojunctions, which includes:

[0046] A drive control unit 1, which internally integrates a data acquisition card, a motion control card, and a stepper motor drive module; a cleaning head 2, on whose cleaning surface a nano-spherical probe matrix is formed; a motor 3, which is controlled by the stepper motor drive module of the drive control unit 1 to displace the cleaning head 2 in the vertical direction, and the vertical direction is the Z-axis; a detection feedback system 4, which includes a capacitive pressure sensor installed between the motor 3 and the cleaning head 2, and detects the acting force of the cleaning head 2 through the capacitive pressure sensor; a sample stage 5, which fixes the two-dimensional material sample.

[0047] The nano-spherical probe matrix of the cleaning head 2 in this embodiment includes a number of nano-spherical probes that work simultaneously. This embodiment does not limit the number of nano-spherical probes included in the nano-spherical probe matrix. For example, the nano-spherical probe matrix can be 50*50 or 10*10. Those skilled in the art can set the specific number of nano-spherical probes according to actual needs; each probe assembly on the cleaning head 2 is essentially still an AFM probe, that is, an atomic force microscope probe. However, different from the traditional one, the cleaning head 2 exists in the form of an actuator in this embodiment, and the nano-spherical probe 20 serves as the core cleaning component to directly perform physical cleaning;

[0048] Also different from the traditional one, the tip of the nano-spherical probe 20 in this embodiment is a smooth spherical structure. By increasing the contact area, the pressure is dispersed under low acting force, reducing damage to the two-dimensional material. The surface roughness of the nano-spherical probe 20 ≤ 0.15nm, approaching atomic-level flatness.

[0049] The motion control card of the drive control unit 1 is connected to the stepper motor drive module, and the stepper motor drive module is connected to the motor 3, thereby forming a communication control connection relationship. The output end of the motor 3 is provided with a rotating shaft that provides a vertical displacement path for the cleaning head 2, so the cleaning head 2 is implemented in a way that approaches the two-dimensional material sample on the sample stage 5.

[0050] The capacitive pressure sensor of the detection feedback system 4 follows the displacement of the cleaning head 2. In actual manufacturing, the capacitive pressure sensor is welded to the cleaning head 2. The acting force of the cleaning head 2 detected by the capacitive pressure sensor is the interaction force generated when the cleaning head 2 contacts the two-dimensional material sample. On this basis, the detection feedback system 4 can feedback the obtained acting force to the drive control unit 1.

[0051] The sample stage 5 fastens the two-dimensional material sample through clips. Specifically, four clips are provided on the sample stage 5 to fasten the two-dimensional material sample at four places.

[0052] The sample stage 5 is implemented to be displaced on the X-axis by the X-axis stepper motor 6, and the sample stage 5 is implemented to be displaced on the Y-axis by the Y-axis stepper motor 7. During actual manufacturing, the structural composition of the motion module is not limited in this embodiment, as long as the displacement of the sample stage 5 on the X-axis and Y-axis can be achieved; for example, the sample stage 5 is assembled on the slider matching the Y-axis stepper motor 7, and this slider is further installed on the X-axis slider to form an orthogonal superimposed structure. The above is only an example for illustration.

[0053] The actual working process of this embodiment is as follows:

[0054] Preparation work,

[0055] First, fix the two-dimensional material sample to be cleaned on the sample stage 5 to ensure that the surface of the two-dimensional material sample is flat and the position is accurate.

[0056] Secondly, according to the characteristics and cleaning requirements of the two-dimensional material sample, set parameters such as the scanning range, speed, and initial acting force of the cleaning brush in the drive control unit 1;

[0057] Finally, start the detection and feedback system 4, and after calibration, ensure that it can accurately monitor the interaction between the cleaning head 2 and the surface of the two-dimensional material sample.

[0058] Cleaning work,

[0059] Start the drive control unit 1 to make the cleaning head 2 slowly approach the surface of the two-dimensional material sample. When the detection and feedback system 4 detects that the nano-spherical probe 20 reaches the set initial acting force with the surface of the two-dimensional material sample, start the scanning cleaning;

[0060] The cleaning head 2 scans on the surface of the two-dimensional material sample according to the preset scanning path. During the scanning process, the detection and feedback system 4 real-time monitors the interaction between the nano-spherical probe 20 and the surface of the two-dimensional material sample, and feeds back the signal to the drive control unit 1. If an abnormal change in the acting force is detected during this period, intervention and adjustment are required to ensure the stable progress of the cleaning process;

[0061] During the cleaning process, for areas on the two-dimensional material sample with relatively serious contamination, the drive control unit 1 can be used to control the nano-spherical probe 20 to perform multiple scans and cleanings until the expected effect is achieved.

[0062] Post-cleaning processing,

[0063] First, reset the device;

[0064] Secondly, detect the cleaned two-dimensional material sample, such as using AFM (Atomic Force Microscope), Raman spectrometer to detect parameters including flatness, roughness, and crystal quality on the surface of the two-dimensional material sample to evaluate the cleaning effect;

[0065] Finally, the cleaning of the two-dimensional material sample with satisfactory cleaning is completed, or the two-dimensional material sample with unsatisfactory cleaning is repeatedly cleaned.

[0066] In this embodiment, as Figure 7 shown is the array pattern of the nano-spherical probes, that is, the array composed of the nano-spherical probes 20 prepared by helium ion implantation. Those skilled in the relevant art can master the actual manufacturing technique under the disclosure of this embodiment. It should be noted that through the high-energy focused helium ion implantation process, the nano-spherical probes 20 are in-situ expanded on the single-crystalline silicon platform at the end of the silicon microcantilever. The diameter range of any single nano-spherical probe 20 is 50 - 200 nm, and the surface roughness is ≤ 0.15 nm, effectively reducing the mechanical damage to the surface of the two-dimensional material during the cleaning process.

[0067] Based on Figure 7 the disclosed structural image, Figure 8 shown is the control chart of the nano-spherical probe cleaning experiment, that is, experiments are conducted under different pressure conditions to verify that the cleaning head 2 can effectively remove the bubbles between molybdenum disulfide and the substrate.

[0068] As Figure 8 shown, the pressure conditions of the specific control experiment are set to 0 nN, 50 nN, 100 nN, and 200 nN, and the pattern ratio is 600 nm; and the change of the height data at the cleaning position under different pressure conditions is disclosed. Specifically:

[0069] Under the condition of a pressure of 0 nN, the height of the cleaning position is 2.8 nm; under the condition of a pressure of 50 nN, the height of the cleaning position is 2.1 nm; under the condition of a pressure of 100 nN, the height of the cleaning position is 1.7 nm; under the condition of a pressure of 200 nN, the height of the cleaning position is 1.4 nm.

[0070] It can be seen from the comparison of these data that with the change of pressure, the cleaning effect of the nano-spherical probe 20 array on the cleaning head 2 on the interface between molybdenum disulfide and the substrate has different effects; the change of the height data reflects the removal of the bubbles, thus verifying that the nano-spherical probe 20 array on the cleaning head 2 can effectively remove the bubbles between molybdenum disulfide and the substrate, proving the feasibility of this embodiment.

[0071] This application discloses a two-dimensional material heterojunction surface cleaner, which uses the cleaning head to transform from a traditional sensor to an actuator, directly participating in the removal of pollutants instead of only being used for observation, and has the following advantages:

[0072] 1. Reduce mechanical damage: The ultrasmooth spherical tip of the nano-spherical probe contacts the surface of two-dimensional materials more uniformly during the cleaning process compared to traditional pyramid-shaped probes, greatly reducing the risk of mechanical damage to the material surface, effectively avoiding the generation of surface defects, protecting the lattice integrity of the material, and improving the material performance.

[0073] 2. Improve cleaning efficiency and effect: The larger contact area enables the nano-spherical probe to act more effectively on the interlayer bubbles and contaminants with less force, resulting in higher cleaning efficiency. At the same time, it can effectively remove the main bubbles and inclusions larger than 1μm, and the cleaning effect is significantly better than traditional methods, improving the surface quality and consistency of two-dimensional materials. The cleaning head forms a probe matrix, and the cleaning efficiency is much higher than that of a single probe.

[0074] 3. Enhance material performance: The two-dimensional material heterostructures treated with nano-spherical probes, such as MoS2 heterostructures, exhibit higher crystal quality, better photoluminescence effect, significantly reduced surface roughness, weakened phonon-electron scattering effect, extended exciton lifetime, and effectively improve the performance of heterostructure devices.

[0075] 4. Avoid chemical contamination: Using a physical cleaning method without the participation of chemical reagents, it avoids the introduction of chemical impurities, ensures the intrinsic properties of two-dimensional materials, and improves the stability and reliability of devices.

[0076] The above embodiments are not limitations to the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions, or substitutions made by those skilled in the art within the scope of the technical solution of the present invention also fall within the protection scope of the present invention.

Claims

1. A two-dimensional material heterojunction surface cleaner, characterized in that Comprising: A drive control unit (1) which integrates a data acquisition card, a motion control card, and a stepper motor drive module inside; A cleaning head (2) whose cleaning surface is formed with a nano-spherical probe matrix. A motor (3) controlled by the stepper motor drive module of the drive control unit (1) to displace the cleaning head (2) in the vertical direction, where the vertical direction is the Z-axis; A detection feedback system (4) including a capacitive pressure sensor installed between the motor (3) and the cleaning head (2), and detecting the acting force of the cleaning head (2) through the capacitive pressure sensor; A sample stage (5) for fixing a two-dimensional material sample.

2. The surface cleaner for two-dimensional material heterojunctions according to claim 1, characterized in that: The nano-spherical probe matrix of the cleaning head (2) includes several simultaneously working nano-spherical probes.

3. The two-dimensional material heterojunction surface cleaner according to claim 1, wherein: The tip of the nano-spherical probe (20) is a spherical structure with a surface roughness ≤ 0.15 nm.

4. The surface cleaner for two-dimensional material heterojunction according to claim 1, characterized in that: The motion control card of the drive control unit (1) is connected to the stepper motor drive module, and the stepper motor drive module is connected to the motor (3).

5. The surface cleaner for two-dimensional material heterojunctions according to claim 4, wherein: The output end of the motor (3) is provided with a rotating shaft that provides a vertical displacement path for the cleaning head (2), and the cleaning head (2) is implemented in a way that approaches the two-dimensional material sample on the sample stage (5).

6. The surface cleaner for two-dimensional material heterojunction according to claim 1, wherein: The capacitive pressure sensor of the detection feedback system (4) follows the displacement of the cleaning head (2), and the acting force of the cleaning head (2) detected by the capacitive pressure sensor is the interaction force generated when the cleaning head (2) contacts the two-dimensional material sample.

7. The surface cleaner for two-dimensional material heterojunction according to claim 1, characterized in that: The sample stage (5) fastens the two-dimensional material sample through a clip.

8. The surface cleaner for two-dimensional material heterojunction according to claim 7, characterized in that: The sample stage (5) is implemented by displacing on the X-axis through an X-axis stepper motor (6), and the sample stage (5) is implemented by displacing on the Y-axis through a Y-axis stepper motor (7).

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