Method and system for laser modification of two-dimensional material and two-dimensional material

Abstract

According to the method and system for modifying the two-dimensional material through the laser and the two-dimensional material, the two-dimensional material to be machined is fixed to the electrode and leveled, the accuracy and stability of the relative position between the area to be modified and the laser focus in the subsequent laser machining process are guaranteed, and a solid foundation is laid for high-precision modification. Ultrafast laser parameters of an ultrafast laser are set, the requirement that the pulse width is larger than 1 ps is determined, and the unique cold machining mechanism of interaction of ultrafast laser and substances is fundamentally utilized; when ultrafast laser with the pulse width larger than 1ps acts on the two-dimensional material, laser energy is absorbed within the time scale far faster than material lattice thermal diffusion due to the extremely high peak power and the extremely short acting time of the ultrafast laser, the nonlinear absorption process is mainly triggered, and therefore accurate removal or modification of the material can be achieved with extremely small thermal influence, and the material can be effectively removed or modified. And melting, splashing and thermal damage caused by traditional long-pulse laser processing are avoided.

Description

Technical Field

[0001] This invention belongs to the field of micro-nano optoelectronic device processing technology, specifically relating to a laser-modified two-dimensional material method, system, and two-dimensional material. Background Technology

[0002] Two-dimensional materials, such as molybdenum disulfide (MoS2) and tungsten diselenide (WSe2), are widely used in photoelectric detection, photovoltaic devices, and flexible electronics due to their excellent photoelectric response characteristics, tunable bandgap, high carrier mobility, and good flexibility. In future semiconductor device packaging and system integration, to meet the demands for multifunctionality, high performance, and miniaturization, devices not only need to possess efficient photoelectric response performance but also need to achieve the synergistic effect of multiple functions such as rectification and logic control. Therefore, developing novel device structures that combine rectification and photoelectric detection functions, and promoting their miniaturization, integration, and high sensitivity, has become one of the important research directions for the present and future.

[0003] Currently, functional modification (such as doping) of two-dimensional materials is one of the key means to control their electrical and optical properties. Chinese invention patent CN110104687A discloses a method for oxygen doping modification of two-dimensional materials, which uses a laser direct-writing system to irradiate the two-dimensional material with a nanosecond laser in an air atmosphere to achieve selective oxygen doping. Although this method can achieve a certain degree of doping control, it still has significant limitations: First, the nanosecond laser pulse width used is relatively wide, resulting in significant thermal effects during processing, falling under the category of thermal processing, which can easily cause thermal damage to the two-dimensional material, affecting the material quality and electrical properties of the modified area; second, this method mainly focuses on material-level doping modification, with its goal and technical effect being to change the carrier concentration, without addressing or being able to achieve specific functions such as integrating photoelectric response and current rectification on a single device.

[0004] Therefore, existing laser modification methods for two-dimensional materials cannot meet the manufacturing requirements for high-quality, high-precision, and functionally integrated two-dimensional material optoelectronic devices. To adapt to the rapid development of micro- and nano-optoelectronic devices, there is an urgent need for a novel processing method that enables low-temperature, non-destructive modification and can directly construct specific electrical functions on two-dimensional materials. Summary of the Invention

[0005] To address the technical problem that existing laser modification methods for two-dimensional materials cannot meet the manufacturing requirements of high-quality, high-precision, and functionally integrated two-dimensional material optoelectronic devices, this invention provides a laser modification method, system, and two-dimensional material for two-dimensional materials.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for laser-modified two-dimensional materials, comprising:

[0008] S1: Fix the two-dimensional material to be processed onto the electrode and level it;

[0009] S2: Set the ultrafast laser parameters of the ultrafast laser, wherein the pulse width of the ultrafast laser is greater than 1 ps;

[0010] S3: Position the area to be modified on the two-dimensional material to be processed at the laser focus;

[0011] S4: Turn on the ultrafast laser and output a single-pulse ultrafast laser to irradiate and modify the region to be modified, causing atomic compression and oxygen doping in the region, thereby changing its Fermi level and forming a functional region with current rectification characteristics between the modified region and the unmodified region.

[0012] Optionally, in step S2, the ultrafast laser parameters set include pulse width and single pulse energy;

[0013] The greater the required atomic compression, the shorter the pulse width and the higher the single pulse energy. The single pulse energy of the ultrafast laser is capped at the level that it cannot cause significant morphological changes to the surface of the two-dimensional material.

[0014] The higher the required oxygen doping level, the higher the laser repetition frequency per second.

[0015] Optionally, in step S3, the laser is focused onto the area to be modified by selecting objective lenses of different magnifications to achieve modification with different precision.

[0016] Optionally, step S5 is also included: after completing the modification of one region, the two-dimensional material to be processed is moved so that the laser focus of the ultrafast laser is in the next region to be modified, and step S4 is repeated until all the set regions are modified.

[0017] Optionally, the method further includes step S6: using a transmission electron microscope to quantitatively characterize the degree of atomic compression in the modified region, and / or using an energy dispersive spectrometer to characterize the oxygen doping in the modified region, and / or using photoelectron spectroscopy to measure the change in the Fermi level in the modified region, and / or using an electrical testing system to measure the rectification properties of the functional region.

[0018] Secondly, the present invention provides a laser-modified two-dimensional material system for realizing the laser-modified two-dimensional material method described above, the system comprising: an ultrafast laser, a precision displacement stage, and electrodes;

[0019] The precision displacement stage is used to move the electrodes that are fixedly mounted on the two-dimensional material.

[0020] The ultrafast laser is movably positioned above the precision displacement stage and is used to output a single-pulse ultrafast laser with a pulse width greater than 1 ps.

[0021] Optionally, the system further includes a beam shaping module and a focusing objective;

[0022] The beam shaping module and the focusing objective are sequentially arranged in the optical path of the ultrafast laser;

[0023] The beam shaping module is used to adjust the spatiotemporal distribution of the ultrafast laser beam; the focusing objective is used to focus the ultrafast laser onto the surface of the two-dimensional material.

[0024] Thirdly, the present invention provides a two-dimensional material, which is prepared based on the laser-modified two-dimensional material method described above, and its surface has a modified region formed by laser modification, wherein a functional region with current rectification characteristics is formed between the modified region and the unmodified region.

[0025] Optionally, the current rectification characteristic is as follows: when a forward bias voltage is applied, the current is cut off; when a reverse bias voltage is applied, the current is turned on.

[0026] Optionally, the two-dimensional material is molybdenum disulfide, tungsten diselenide, or graphene.

[0027] The beneficial effects of this invention are:

[0028] This invention provides a laser-modified method for two-dimensional materials. By fixing and leveling the two-dimensional material to be processed on an electrode, the accuracy and stability of the relative position between the region to be modified and the laser focus are ensured during subsequent laser processing, laying a solid foundation for high-precision modification. By setting the ultrafast laser parameters of the ultrafast laser and explicitly requiring a pulse width greater than 1 ps, the unique cold processing mechanism of ultrafast laser-matter interaction is fundamentally utilized, avoiding the melting, sputtering, and thermal damage layers caused by traditional long-pulse laser processing. This is crucial for maintaining the intrinsic electrical properties of atomically thin two-dimensional materials. The precise positioning of the region to be modified on the two-dimensional material to be processed at the laser focus achieves a balance between processing efficiency and precision. Finally, irradiation modification is performed by outputting a single-pulse ultrafast laser, inducing atomic extrusion and oxygen doping in the region, effectively changing the local Fermi level of the two-dimensional material, thereby forming a built-in electric field between the modified and unmodified regions, and ultimately successfully constructing a functional region with current rectification characteristics.

[0029] This method is the first to combine the advantages of ultrafast laser cold processing with band engineering of two-dimensional materials, creating functional junctions directly within the material and providing a novel solution for integrating optoelectronic devices on a single two-dimensional material substrate. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the laser modification method for two-dimensional materials in this invention.

[0031] Figure 2 This is a schematic diagram of step S5 in this invention;

[0032] Figure 3 This is a schematic diagram of the quantitative characterization of the degree of atomic compression using a transmission electron microscope in step S6 of the present invention.

[0033] Figure 4 This is a schematic diagram of the quantitative characterization of oxygen doping using an energy dispersive spectrometer in step S6 of the present invention.

[0034] Figure 5 This is a schematic diagram of measuring the change of the Fermi level using photoelectron spectroscopy in step S6 of this invention;

[0035] Figure 6 This is a schematic diagram of measuring the rectification properties of a material using an electrical testing system in step S6 of this invention. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0038] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0039] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0040] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0041] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0042] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0043] Example 1

[0044] See Figure 1 The diagram illustrates a laser-modified two-dimensional material method according to the present invention, comprising:

[0045] S1: Fix the two-dimensional material to be processed onto the electrode and level it;

[0046] S2: Set the ultrafast laser parameters of the ultrafast laser, the pulse width of the ultrafast laser is greater than 1ps;

[0047] S3: Position the area to be modified on the two-dimensional material to be processed at the laser focus;

[0048] S4: Turn on the ultrafast laser and output a single-pulse ultrafast laser to irradiate and modify the region to be modified, causing atomic compression and oxygen doping in the region, thereby changing its Fermi level and forming a functional region with current rectification characteristics between the modified and unmodified regions.

[0049] This embodiment provides a laser modification method for two-dimensional materials. By fixing and leveling the two-dimensional material to be processed on an electrode, the accuracy and stability of the relative position between the area to be modified and the laser focus are ensured during subsequent laser processing, laying a solid foundation for high-precision modification. By setting the ultrafast laser parameters of the ultrafast laser and explicitly requiring a pulse width greater than 1 ps, the unique cold processing mechanism of ultrafast laser-matter interaction is fundamentally utilized. When an ultrafast laser with a pulse width greater than 1 ps acts on a two-dimensional material, its extremely high peak power and extremely short action time allow the laser energy to be absorbed on a timescale much faster than the thermal diffusion of the material's lattice, mainly inducing a nonlinear absorption process. This enables precise removal or modification of the material with minimal thermal impact, avoiding the melting, sputtering, and thermal damage layers caused by traditional long-pulse laser processing. This is crucial for maintaining the intrinsic electrical properties of two-dimensional materials with atomic-level thickness. Precisely positioning the area to be modified on the two-dimensional material at the laser focus ensures that the laser energy acts on the target area with the highest power density, achieving a balance between processing efficiency and precision.

[0050] Ultimately, irradiation modification using a single-pulse ultrafast laser induced atomic extrusion and oxygen doping in the region. This process resulted from a series of rapid thermodynamic relaxation behaviors triggered by ultrafast laser energy injection. The atomic-level lattice distortion, combined with the incorporation of oxygen from the environment, effectively altered the local Fermi level of the two-dimensional material, thereby creating a built-in electric field between the modified and unmodified regions. This successfully constructed a functional region with current rectification characteristics. This method, for the first time, combines the cold processing advantages of ultrafast lasers with band engineering of two-dimensional materials, directly creating functional junctions within the material and providing a novel solution for integrating optoelectronic devices on a single two-dimensional material substrate.

[0051] Optionally, in step S2 of the present invention, the ultrafast laser parameters set include pulse width and single pulse energy;

[0052] The greater the required atomic compression, the shorter the pulse width and the higher the single pulse energy. However, the single pulse energy of ultrafast lasers cannot cause significant morphological changes to the surface of two-dimensional materials, i.e., it is limited to micro-modification.

[0053] The higher the required oxygen doping level, the higher the laser repetition frequency per second.

[0054] In this embodiment, the adjustment strategy for ultrafast laser parameters is further refined, and a quantitative correlation between laser parameters and modification effects is established, greatly improving the controllability and flexibility of the processing method. Specifically, by establishing adjustment principles, shorter pulse widths mean more extreme high power density and more instantaneous energy deposition, which can generate stronger shock wave effects and more significant nonlinear effects, thereby applying stronger mechanical stress to the atomic lattice of two-dimensional materials, resulting in more obvious interatomic spacing compression (i.e., atomic squeezing). Higher single-pulse energy that does not damage the surface of two-dimensional materials directly provides the energy threshold required to achieve this lattice distortion. On the other hand, because a higher laser repetition frequency means an increase in the number of pulses acting on the same point of the material per unit time and a shorter pulse interval, this will produce a controllable, slight thermal accumulation effect in the processing area. This mild thermal accumulation is not the harmful thermal damage of traditional thermal processing, but an auxiliary effect based on ultrafast laser cold processing. It can promote oxygen molecules in the surrounding environment of the processing area to obtain higher activation energies, thereby more effectively diffusing and incorporating into the lattice vacancies generated by laser irradiation, achieving a higher concentration of oxygen doping.

[0055] This ability to reverse-engineer laser parameters based on the target effect enables the method to adapt to the different requirements of different two-dimensional material systems and different devices for rectification characteristics (such as rectification ratio and turn-on voltage), demonstrating the high degree of intelligence and universality of the process.

[0056] Furthermore, in practical applications, the upper limit of the single-pulse energy of the ultrafast laser corresponding to the two-dimensional material to be modified should first be determined experimentally. Specifically, for example, the upper limit of the single-pulse energy of the ultrafast laser corresponding to single-crystal silicon is 1 J / cm². 2 The upper limit of the single-pulse energy of the ultrafast laser corresponding to molybdenum disulfide is 0.1 J / cm². 2 .

[0057] Optionally, in step S3 of the present invention, the laser is focused on the area to be modified by selecting objective lenses of different magnifications to achieve modification with different precision.

[0058] Optionally, refer to Figure 2 The laser modification method for two-dimensional materials in this invention further includes step S5: after completing the modification of one region, the two-dimensional material to be processed is moved so that the laser focus of the ultrafast laser is located in the next region to be modified, and step S4 is repeated until all set regions are modified.

[0059] Optionally, refer to Figures 3 to 5 The laser-modified two-dimensional material method of the present invention further includes step S6: using a transmission electron microscope to quantitatively characterize the degree of atomic compression in the modified region, and / or using an energy dispersive spectrometer to characterize the oxygen doping in the modified region, and / or using photoelectron spectroscopy to measure the change in the Fermi level in the modified region, and / or using an electrical testing system to measure the rectification properties of the functional region.

[0060] In this embodiment, a complete and multi-dimensional characterization method system is introduced to quantitatively evaluate and verify the laser modification effect, thereby realizing closed-loop optimization of the processing technology and reliable control of product quality.

[0061] Specifically, using transmission electron microscopy to quantify the degree of atomic compression allows for direct, atomic-scale observation of changes in the lattice constant of two-dimensional materials after laser irradiation, and precise measurement of changes in interatomic spacing, providing the most direct evidence for understanding the atomic-level mechanical effects induced by ultrafast lasers. Using energy dispersive spectroscopy to characterize oxygen doping allows for qualitative and quantitative analysis of the oxygen content and distribution in the two-dimensional material, confirming the successful implementation and uniformity of oxygen doping. Measuring the Fermi level change using photoelectron spectroscopy reveals the essence of the modification behavior at the electronic structure level—how laser modification, through the combined effects of atomic compression and oxygen doping, modulates the material's band structure, causing a shift in its Fermi level, which is the physical basis for the rectification characteristics. Finally, using an electrical testing system to directly measure the material's rectification properties, such as the current voltage characteristic curve, verifies whether the final goal of this modification has been achieved at the device functional level, obtaining key performance parameters such as rectification ratio and threshold voltage. This characterization system organically links microstructure, chemical composition, electronic band structure, and macroscopic electrical properties. It is not only used for result verification, but also for guiding the optimization of laser parameters to ensure that the prepared functional regions have reliable performance and meet design expectations.

[0062] Furthermore, the greater the degree of atomic compression in the modified region, or the higher the degree of oxygen doping, the greater the change in its Fermi level, and the more obvious the corresponding rectification characteristics will be.

[0063] Furthermore, if the test results show that the product produced by the current processing does not meet the requirements, such as the finishing effect is not obvious, the single pulse energy of the ultrafast laser in the subsequent processing can be increased accordingly.

[0064] Example 2

[0065] The present invention also provides a laser-modified two-dimensional material system for implementing the laser-modified two-dimensional material method in Embodiment 1. The system includes: an ultrafast laser, a precision displacement stage, and electrodes.

[0066] Precision displacement stage is used to move electrodes that are fixedly mounted on two-dimensional materials;

[0067] The ultrafast laser is mounted above the precision displacement stage and is used to output single-pulse ultrafast laser with a pulse width greater than 1 ps.

[0068] Optionally, the system of the present invention further includes a beam shaping module and a focusing objective;

[0069] The beam shaping module and the focusing objective are sequentially arranged in the optical path of the ultrafast laser;

[0070] The beam shaping module is used to adjust the spatiotemporal distribution of the ultrafast laser beam; the focusing objective is used to focus the ultrafast laser onto the surface of a two-dimensional material.

[0071] In this embodiment, a laser-modified two-dimensional material system is provided. It should be noted that the laser-modified two-dimensional material system in this embodiment corresponds to the laser-modified two-dimensional material method in Embodiment 1, and its usage and beneficial effects are the same, so they will not be described in detail here.

[0072] Example 3

[0073] The present invention also provides a two-dimensional material, which is prepared based on the laser-modified two-dimensional material method in Example 1. The surface of the material has a modified region formed by laser modification, and a functional area with current rectification characteristics is formed between the modified region and the unmodified region.

[0074] Optionally, the current rectification characteristics in this invention are as follows: when a forward bias voltage is applied, the current is cut off; when a reverse bias voltage is applied, the current is turned on.

[0075] Optionally, the two-dimensional material in this invention is molybdenum disulfide, tungsten diselenide, or graphene.

[0076] For an introduction to the laser modification method and beneficial effects of the above-mentioned two-dimensional materials, please refer to Example 1. For the sake of brevity, no specific details are provided in this example.

[0077] Example 4

[0078] In this embodiment, the laser-modified two-dimensional material method in Example 1 is described in detail by way of example.

[0079] Example 1: Laser-modified doping of molybdenum disulfide

[0080] S1: Fix the molybdenum disulfide to be processed onto the gold electrode and level it;

[0081] S2: Set appropriate ultrafast laser parameters, specifically pulse width of 1 ps and single pulse energy of 30 nJ;

[0082] S3: Select a 20X NIR objective lens and move the molybdenum disulfide to be processed so that the area to be modified is positioned at the laser focus.

[0083] S4: Turn on the ultrafast laser and output a single-pulse ultrafast laser to modify the area to be modified on the molybdenum disulfide to be processed;

[0084] S5: After completing the modification of one area, move the molybdenum disulfide to be modified to the next area to be modified, and repeat step S4 until all the set areas are modified.

[0085] S6: Use transmission electron microscopy to quantify the degree of atomic compression, and / or use energy dispersive spectroscopy to characterize oxygen doping, and / or use photoelectron spectroscopy to measure changes in the Fermi level, and / or use an electrical testing system to measure the rectification properties of the material.

[0086] Example 2: Laser-modified doping of molybdenum diselenide

[0087] S1: Fix the molybdenum diselenide to be processed onto the gold electrode and level it;

[0088] S2: Set appropriate ultrafast laser parameters, specifically pulse width of 1 ps and single pulse energy of 30 nJ;

[0089] S3: Select a 30X NIR objective lens and move the molybdenum diselenide to be processed so that the area to be modified is positioned at the laser focus.

[0090] S4: Turn on the ultrafast laser and output a single-pulse ultrafast laser to modify the area to be modified on the molybdenum diselenide to be processed;

[0091] S5: After completing the modification of one region, move the molybdenum diselenide to be modified to the next region to be modified, and repeat step S4 until all the set regions have been modified.

[0092] S6: Use transmission electron microscopy to quantify the degree of atomic compression, and / or use energy dispersive spectroscopy to characterize oxygen doping, and / or use photoelectron spectroscopy to measure changes in the Fermi level, and / or use an electrical testing system to measure the rectification properties of the material.

Claims

1. A method for laser modification of two-dimensional materials, characterized in that, include: S1: Fix the two-dimensional material to be processed onto the electrode and level it; S2: Set the ultrafast laser parameters of the ultrafast laser, wherein the pulse width of the ultrafast laser is greater than 1 ps; S3: Position the area to be modified on the two-dimensional material to be processed at the laser focus; S4: Turn on the ultrafast laser and output a single-pulse ultrafast laser to irradiate and modify the region to be modified, causing atomic compression and oxygen doping in the region, thereby changing its Fermi level and forming a functional region with current rectification characteristics between the modified region and the unmodified region.

2. The laser modification method for two-dimensional materials according to claim 1, characterized in that, In step S2, the ultrafast laser parameters set include pulse width and single pulse energy. The greater the required atomic compression, the shorter the pulse width and the higher the single pulse energy. The single pulse energy of the ultrafast laser is capped at the level that it cannot cause significant morphological changes to the surface of the two-dimensional material. The higher the required oxygen doping level, the higher the laser repetition frequency per second.

3. The laser-modified two-dimensional material method according to claim 1 or 2, characterized in that, In step S3, laser light is focused onto the area to be modified by selecting objective lenses of different magnifications to achieve modification with different precision.

4. The laser modification method for two-dimensional materials according to claim 1, characterized in that, It also includes step S5: After completing the modification of one region, move the two-dimensional material to be processed so that the laser focus of the ultrafast laser is in the next region to be modified, and repeat step S4 until all the set regions are modified.

5. The laser-modified two-dimensional material method according to claim 4, characterized in that, The method further includes step S6: using a transmission electron microscope to quantitatively characterize the degree of atomic compression in the modified region, and / or using an energy dispersive spectrometer to characterize the oxygen doping in the modified region, and / or using photoelectron spectroscopy to measure the change in the Fermi level in the modified region, and / or using an electrical testing system to measure the rectification properties of the functional region.

6. A laser-modified two-dimensional material system for realizing the laser-modified two-dimensional material method according to any one of claims 1 to 5, characterized in that, The system includes: an ultrafast laser, a precision displacement stage, and electrodes; The precision displacement stage is used to move the electrodes that are fixedly mounted on the two-dimensional material. The ultrafast laser is movably positioned above the precision displacement stage and is used to output a single-pulse ultrafast laser with a pulse width greater than 1 ps.

7. The laser-modified two-dimensional material system according to claim 6, characterized in that, The system also includes a beam shaping module and a focusing objective; The beam shaping module and the focusing objective are sequentially arranged in the optical path of the ultrafast laser; The beam shaping module is used to adjust the spatiotemporal distribution of the ultrafast laser beam; the focusing objective is used to focus the ultrafast laser onto the surface of the two-dimensional material.

8. A two-dimensional material, characterized in that, The two-dimensional material is prepared based on the laser-modified two-dimensional material method according to any one of claims 1 to 5, and its surface has a modified region formed by laser modification, wherein a functional area with current rectification characteristics is formed between the modified region and the unmodified region.

9. The two-dimensional material according to claim 8, characterized in that, The current rectification characteristic is as follows: when a forward bias is applied, the current is cut off; when a reverse bias is applied, the current is turned on.

10. The two-dimensional material according to claim 8 or 9, characterized in that, The two-dimensional material is molybdenum disulfide, tungsten diselenide, or graphene.

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