Double-gate regulation and control graphene micro-nano structure terahertz detector and preparation method thereof

Abstract

The invention discloses a dual-gate regulation and control graphene micro-nano structure terahertz detector and a preparation method thereof. The dual-gate regulation and control graphene micro-nano structure terahertz detector comprises an effective detection part layer and a substrate layer, the effective detection part layer comprises a bigrid metal electrode, an insulating dielectric layer, a graphene layer and a source-drain metal electrode; the bigrid metal electrode is coated in the insulating dielectric layer, and the connecting surface of the bigrid metal electrode is in close contact with the substrate layer; the insulating dielectric layer is arranged above the substrate layer; the graphene layer is located above the insulating dielectric layer and comprises a graphene patterned structure array formed by circular structure sub-arrays or polygonal structure sub-arrays connected by strips; the bigrid metal electrode is located in a space, mapped on the insulating dielectric layer, of the graphene patterned structure array; the source and drain metal electrodes are arranged above the insulating dielectric layer, cover the two ends of the graphene layer respectively and are electrically connected with the graphene layer. The terahertz detector provided by the invention supports the middle infrared to terahertz wave band, and realizes high-response detection and wide-spectrum response in a greenhouse.

Description

Technical Field

[0001] The present invention relates to the technical field of terahertz wave detection, and in particular to a double-gate regulated graphene micro-nano structure terahertz detector and a preparation method thereof. Background Art

[0002] Terahertz waves refer to electromagnetic waves with a frequency range of 0.1T to 10Thz. They have the characteristics of low photon energy, high penetration, high bandwidth, high resolution and rich molecular fingerprint spectrum, which makes terahertz technology have broad application prospects in communication, bio-imaging, medical diagnosis and security detection. The core functional devices of terahertz technology mainly include terahertz sources, terahertz modulators and terahertz detectors. Traditional terahertz detectors mainly include thermal detectors, such as microbolometers and Golay detectors, photonic detectors, such as low-temperature superconducting STJ detectors and Schottky detectors, and electronic detectors, such as field-effect transistors. However, microbolometers and low-temperature superconducting STJ detectors need to be at low or even ultra-low temperatures to achieve the best detection results. Golay detectors have a long response time, and Schottky detectors and field-effect transistors have narrow response spectra. Therefore, the performance of existing terahertz detectors is restricted by the device structure, resulting in poor detection efficiency and adaptability of terahertz detectors.

[0003] It can be seen that how to design a terahertz detector to improve the detection efficiency and adaptability of the terahertz detector has become a technical problem that needs to be urgently solved by those skilled in the art. Summary of the invention

[0004] The present invention provides a dual-gate regulated graphene micro-nanostructure terahertz detector and a preparation method thereof, so as to solve the technical problem of how to design a terahertz detector to improve the detection efficiency and adaptability range of the terahertz detector, and to improve the response spectrum width and response rate of the terahertz detector.

[0005] In a first aspect, the present invention provides a dual-gate regulated graphene micro-nanostructure terahertz detector, comprising: an effective detection layer and a substrate layer; The effective detection layer includes a dual-gate metal electrode, an insulating dielectric layer, a graphene layer and a source-drain metal electrode; The dual-gate metal electrode is coated in the insulating dielectric layer, and the connection surface of the dual-gate metal electrode is in close contact with the substrate layer; The insulating dielectric layer is disposed above the substrate layer; The graphene layer is located above the insulating dielectric layer, and includes a graphene patterned structure array, wherein the graphene patterned structure array is composed of circular structure sub-arrays or polygonal structure sub-arrays connected by strips; The dual-gate metal electrode is partially or completely located in the space where the graphene patterned structure array is mapped on the insulating dielectric layer; The source-drain metal electrodes are arranged above the insulating dielectric layer, and the source-drain metal electrodes respectively cover two ends of the graphene patterned structure array and are electrically connected to the graphene patterned structure array.

[0006] Preferably, the circular diameter of the circular structure subarrays ranges from 0.1 μm to 200 μm, and the width of the corresponding strips connecting the circular structure subarrays ranges from 1 / 10 to 1 / 2 of the circular diameter.

[0007] Preferably, the size range of the polygonal side length of the polygonal structure subarray is 0.1 μm to 200 μm, and the width of the corresponding strip connecting the polygonal structure subarray is 1 / 10 to 1 / 2 of the polygonal side length.

[0008] Preferably, the spacing between adjacent circles of the circular structure subarray is 0.2 μm to 500 μm, and the number of circles is 2 to 100; The distance between adjacent polygons of the polygon structure subarray is 0.2 μm-500 μm, and the number of polygons is 2-100.

[0009] Preferably, the dual gate metal electrode comprises two independent gate metal electrodes; The shapes of the source-drain metal electrode and the dual-gate metal electrode are circular within a first size range or polygonal within a second size range; The first size range is a size range of circular diameter of 10 μm to 1000 μm; The second size range is a size range of 10 μm to 1000 μm for the side length of the polygon.

[0010] Preferably, the source-drain metal electrode and the dual-gate metal electrode are a single material of any one of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel; or, the source-drain metal electrode and the dual-gate metal electrode are a composite material composed of at least two of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel; The insulating dielectric layer is a single material of any one of SiO2, Al2O3, HfO2, Si3N4, MgO, MnO2, h-BN, diamond, mica and polymer material films; or, the insulating dielectric layer is a composite material composed of at least two of SiO2, Al2O3, HfO2, Si3N4, MgO, MnO2, h-BN, diamond, mica and polymer material films.

[0011] Preferably, the thickness of the source-drain metal electrode is greater than the thickness of the graphene layer.

[0012] Preferably, the thickness of the dual-gate metal electrode is smaller than the thickness of the insulating dielectric layer.

[0013] Preferably, the thickness of the substrate layer is less than or equal to 1000 μm.

[0014] In a second aspect, the present invention further provides a method for preparing a dual-gate regulated graphene micro-nanostructure terahertz detector, which is used to prepare the dual-gate regulated graphene micro-nanostructure terahertz detector disclosed above, and the preparation method comprises: Performing sputtering, deposition or evaporation treatment on one surface of the obtained substrate layer to form a double gate metal electrode; Performing oxidation and deposition treatment on the surface of the substrate layer on which the dual-gate metal electrode is prepared to form an insulating dielectric layer; Transferring graphene to a side of the insulating dielectric layer away from the substrate layer, and patterning the graphene to obtain a graphene layer; Photolithography, sputtering, deposition or evaporation treatment is performed on two opposite ends of the graphene layer to form source and drain metal electrodes to obtain the double-gate controlled graphene micro-nanostructure terahertz detector.

[0015] The present application provides a dual-gate controlled graphene micro-nanostructure terahertz detector and a preparation method thereof. Compared with the prior art, the beneficial effects of the embodiments of the present invention are as follows: The dual-gate controllable graphene micro-nanostructure terahertz detector of the present application consists of a graphene layer of a patterned structure array, a dual-gate metal electrode, an insulating dielectric layer and a source-drain metal electrode. The Fermi level of the graphene layer can be flexibly controlled by applying an external voltage to the dual-gate metal electrode. It has low loss, supports mid-infrared to terahertz bands, realizes greenhouse response and wide spectrum response, and has high responsiveness, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the main structure of a double-gate regulated graphene micro-nanostructure terahertz detector provided by a preferred embodiment of the present invention; Figure 2 It is a schematic diagram of a top view of a double-gate regulated graphene micro-nanostructure terahertz detector provided by a preferred embodiment of the present invention; Figure 3 It is a schematic diagram of the light response size of a double-gate regulated graphene micro-nanostructure terahertz detector under different gate voltages under 2.52THz laser irradiation provided by a preferred embodiment of the present invention; Figure 4This is a graphene Raman scattering spectrum of a double-gate regulated graphene micro-nanostructure terahertz detector provided by a preferred embodiment of the present invention; Figure 5 It is a schematic diagram of the light response size of a double-gate regulated graphene micro-nanostructure terahertz detector under different gate voltages under different frequency laser irradiation provided by a preferred embodiment of the present invention; Figure 6 It is a schematic diagram of the steps of a method for preparing a double-gate controlled graphene micro-nanostructure terahertz detector provided by a preferred embodiment of the present invention; Reference numerals: 1-source metal electrode, 2-graphene layer, 3-drain metal electrode, 4-insulating dielectric layer, 5-dual gate metal electrode, 6-substrate layer. DETAILED DESCRIPTION

[0017] The following is a detailed explanation of the implementation mode of the present invention in conjunction with the accompanying drawings. The embodiments are provided only for illustrative purposes and cannot be understood as limiting the present invention. The accompanying drawings are only for reference and illustration purposes and do not constitute a limitation on the scope of patent protection of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In the description of the present invention, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", "third", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, the meaning of "multiple" is two or more.

[0018] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. The terms "vertical", "horizontal", "left", "right", "upper", "lower" and similar expressions used herein are only for illustrative purposes, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] In the description of the present invention, it should be noted that, unless otherwise defined, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those skilled in the art. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0020] Two-dimensional materials refer to materials in which electrons move freely only on the nanoscale in two dimensions, such as nanofilms and superlattices. Two-dimensional materials are highly ordered in structure, usually grown on a two-dimensional plane, and have a clear layered structure. Two-dimensional materials have quantum confinement in the layer direction, which makes two-dimensional materials exhibit electronic properties that traditional bulk materials do not have, such as adjustable band gaps, higher carrier mobility, and less dielectric screening effects. Plasmon polaritons are a special mode formed by the coupling of plasmons and light. Plasmons are collective oscillations formed by electrons when light irradiates solid materials. In two-dimensional materials, since plasmons are confined to a plane, their attenuation is greatly suppressed. Therefore, the frequency range of plasmon polaritons in two-dimensional materials is wide, covering terahertz waves to ultraviolet bands, providing an effective way to improve the detection performance of terahertz detectors. Plasmon polaritons were first discovered in metals. They can localize light fields in the subwavelength range and improve the absorption of incident light, but they have poor tunability and only support the near-infrared band.

[0021] Among two-dimensional materials, graphene has properties such as zero band gap and adjustable Fermi level, which makes its plasmon polariton effect well tunable and has low loss, supporting the mid-infrared to terahertz band.

[0022] In view of this, in an embodiment of the present invention, a dual-gate regulated graphene micro-nanostructure terahertz detector is provided, see Figure 1, including an effective detection layer and a substrate layer 6; wherein the effective detection layer includes a dual-gate metal electrode 5, an insulating dielectric layer 4, a graphene layer 2 and a source-drain metal electrode; the dual-gate metal electrode 5 is coated in the insulating dielectric layer 4, and the connection surface of the dual-gate metal electrode 5 is in close contact with the substrate layer 6; the insulating dielectric layer 4 is arranged above the substrate layer 6; the graphene layer 2 is located above the insulating dielectric layer 4, and includes a graphene patterned structure array, the graphene patterned structure array is composed of a circular structure sub-array or a polygonal structure sub-array connected by strips, and the dual-gate metal electrode 5 is completely or partially located in the space where the graphene patterned structure array is mapped on the insulating dielectric layer 4; the source-drain metal electrode is arranged above the insulating dielectric layer 4, and the source-drain metal electrode covers the two ends of the graphene patterned structure array respectively, and is electrically connected to the graphene patterned structure array; wherein the electrical connection can be a direct contact connection or an indirect contact connection; the effective detection layer should be arranged on the substrate layer 6.

[0023] In the process of terahertz wave detection, the dual-gate controlled graphene micro-nanostructure terahertz detector provided by the present application irradiates the graphene patterned structure array with the terahertz wave, obtains a current signal or a voltage signal at the source-drain metal electrode, applies a voltage to the dual-gate metal electrode 5, and changes the magnitude and polarity of the voltage signal or the current signal at the source-drain metal electrode. The graphene patterned structure array generates a plasmon polariton effect with the incident terahertz wave, thereby improving the absorption efficiency of the graphene patterned structure array to the terahertz wave. Applying a voltage to the gate can regulate the graphene Fermi level, thereby regulating the photothermoelectric effect caused by the plasmon effect of the graphene patterned structure array, achieving a stronger terahertz wave responsiveness, more flexible control, more precise frequency selectivity, and a wider response spectrum, so that it can also work normally under normal temperature conditions.

[0024] The photothermoelectric effect is a physical phenomenon in which a substance generates heat and thus produces an electrical effect under the action of light. It is a representative photoelectric response mechanism in graphene photodetectors. Since the energy of terahertz waves is at the meV level (much smaller than the energy of interband excitation, which is 2Ef), the incident light excites hot carriers in the graphene patterned structure array mainly through the band. In addition, the dual-gate regulated graphene micro-nanostructure terahertz detector can couple terahertz wave signals and generate hot carriers at both ends of the graphene patterned structure array. The Fermi level at both ends of the graphene patterned structure array is adjusted by the dual-gate metal electrode 5, so that the temperature at both ends of the graphene patterned structure array can be different. The photothermoelectric effect converts different temperatures into a voltage difference at both ends of the graphene patterned structure array, generating a photoresponse. The hot carriers excited by the graphene patterned structure array can only be cooled by acoustic phonons. At the same time, the small Fermi surface and the law of conservation of momentum limit the scattering of acoustic phonons on electrons, that is, the scattering effect of electrons and phonons in the graphene patterned structure array is weak, while the scattering effect of electrons and electrons is relatively strong. The interaction between electrons and electrons in the graphene patterned structure array is also shorter than the interaction between electrons and phonons. Since the electronic heat capacity of graphene is much smaller than the lattice heat capacity, the electrons quickly form a temperature gradient (50fs) after absorbing the terahertz wave, and maintain the temperature difference with the lattice during the electron-phonon relaxation time. Under the action of the non-equilibrium electronic temperature gradient, the electrons produce a directional flow to form a measurable photocurrent. Based on the principle of electronic interaction, the response speed of the double-gate regulated graphene micro-nanostructure terahertz detector provided in the embodiment of the present application can be compared with that of a photon-type detector. In theory, the limit response speed can reach the order of ps.

[0025] The graphene patterned structure array is a circular structure subarray or a polygonal structure subarray connected by strips. In a preferred embodiment of the present application, if it is a circular structure subarray, the size range of the circular diameter of the circular structure subarray is 0.1μm~200μm, and the corresponding width of the strip connecting the circular structure subarray is 1 / 10~1 / 2 of the circular diameter; if it is a polygonal structure subarray, the size range of the side length of the polygonal structure subarray is 0.1μm~200μm, and the corresponding width of the strip connecting the polygonal structure subarray is 1 / 10~1 / 2 of the side length of the polygon. In the longitudinal and transverse structures of the circular structure subarray, the spacing between adjacent circles is 0.2μm~500μm, and the number of circles is 2~100; in the longitudinal and transverse structures of the polygonal structure subarray, the distance between adjacent polygons is 0.2μm~500μm, and the number of polygons is 2~100. Figure 2The figure shows a top-down structural diagram of a dual-gate controlled graphene micro-nanostructure terahertz detector, which is a circular structure subarray with a radius of 15um. The strips connecting the circles are rectangular, 3um wide and 300um long. In the horizontal and vertical structures of the circular structure subarray, the spacing between adjacent circles is 33um, and the number of repetitions is 10 and 5 respectively.

[0026] The source and drain metal electrodes are arranged above the insulating dielectric layer 4, and the source metal electrode 1 and the drain metal electrode 3 are respectively covered at both ends of the graphene patterned structure array. In the preferred embodiment of the present application, the source and drain metal electrodes are directly contacted and connected with the graphene patterned structure array, and the thickness is greater than the thickness of the graphene layer 2. The material of the source and drain metal electrodes is a single material of any one of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel, or a composite material composed of at least two of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel. Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel have good electrical conductivity and large dielectric constant, which can effectively improve the detection performance of the dual-gate controlled graphene micro-nano structure terahertz detector. The shape of the source and drain metal electrodes is circular or polygonal. When it is circular, the size range of the circular diameter is 10μm~1000μm, and when it is polygonal, the size range of the polygon side length is 10μm~1000μm.

[0027] In a preferred embodiment of the present application, the dual-gate metal electrode 5 includes two independent gate metal electrodes, which are coated in the insulating dielectric layer 4, and the connection surface of the dual-gate metal electrode 5 is in close contact with the substrate layer 6, and is partially or completely located in the space where the graphene patterned structure array is mapped on the insulating dielectric layer 4. Based on the input voltage of the dual-gate metal electrode 5, the graphene Fermi level is regulated, and the photothermoelectric effect of the dual-gate regulated graphene micro-nano structure terahertz detector is regulated at the same time, and the polarity and size of the photocurrent or photovoltage of the dual-gate regulated graphene micro-nano structure terahertz detector are changed, so that it can be turned off and on, giving the terahertz detector new functions, such as Figure 3 The figure shows the light response size of the dual-gate controlled graphene micro-nanostructure terahertz detector under 2.52THz laser irradiation and different gate voltages. Figure 4 The graphene Raman scattering spectrum of the graphene micro-nanostructure terahertz detector with dual-gate control is shown. With the difference of the voltage of the dual-gate metal electrode 5, the direction of the light response voltage between the source and drain metal electrodes changes. The left side is positive photoelectric response, the right side is negative photoelectric response, and the middle part is close to 0, which is impossible for single-gate control. Figure 5It is a schematic diagram of the light response size of a dual-gate controlled graphene micro-nanostructure terahertz detector under different frequency laser irradiation and different gate voltages provided by a preferred embodiment of the present invention. At different frequencies, the relationship curve between the light response and the gate voltage is different, indicating that the device has the characteristics of wide spectrum and frequency selection.

[0028] In a preferred embodiment of the present application, the material of the gate metal electrode is a single material of any one of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel, or a composite material composed of at least two of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel. Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel have good electrical conductivity and large dielectric constant, and can effectively improve the detection performance of the dual-gate regulated graphene micro-nano structure terahertz detector. The shape of the gate metal electrode is also circular or polygonal. When it is circular, the size range of the circular diameter is 10μm~1000μm, and when it is polygonal, the size range of the polygon side length is 10μm~1000μm.

[0029] In the preferred embodiment of the present application, the material of the insulating dielectric layer 4 is a single material of any one of SiO2, Al2O3, HfO2, Si3N4, MgO, MnO2, h-BN, diamond, mica and polymer material films, or a composite material composed of at least two of SiO2, Al2O3, HfO2, Si3N4, MgO, MnO2, h-BN, diamond, mica and polymer material films, and has good insulation performance. The thickness of the insulating dielectric layer 4 is 0.001μm~2μm, and the thickness of the insulating dielectric layer 4 is greater than the thickness of the dual-gate metal electrode 5, so as to be able to completely cover the dual-gate metal electrode 5, so that only the connection surface of the dual-gate metal electrode 5 is in contact with the substrate layer 6. The smaller the thickness of the insulating dielectric layer 4, the stronger the control ability of the dual-gate metal electrode 5 on the graphene layer 2, and the better the insulation performance of the insulating dielectric layer 4. On the premise of meeting the insulation performance requirements, the thickness of the insulating dielectric layer 4 can be reduced as much as possible to enhance the control ability of the dual-gate metal electrode 5 on the graphene layer 2.

[0030] In a preferred embodiment of the present application, the substrate layer 6 is a single material of any one of a polymer flexible film, an intrinsic semiconductor material, and a doped semiconductor material containing other elements, or a composite material composed of at least two of the polymer flexible film, the intrinsic semiconductor material, and the doped semiconductor material containing other elements, and the thickness of the substrate layer 6 is less than or equal to 1000 μm. The substrate layer 6 can also be above the graphene layer 2 and directly contact the graphene layer 2.

[0031] The dual-gate controllable graphene micro-nanostructure terahertz detector provided in the present application is composed of a graphene layer 2 of a patterned structure array, a dual-gate metal electrode 5, an insulating dielectric layer 4 and a source-drain metal electrode to form an effective detection layer. The Fermi level of the graphene layer 2 can be flexibly controlled by applying an external voltage to the dual-gate metal electrode 5, with low loss, supporting mid-infrared to terahertz bands, and having good application prospects.

[0032] Accordingly, in a preferred embodiment of the present invention, based on the dual-gate regulated graphene micro-nano structure terahertz detector of the present application, the present embodiment further provides a method for preparing the dual-gate regulated graphene micro-nano structure terahertz detector, which is used to prepare the dual-gate regulated graphene micro-nano structure terahertz detector disclosed in the embodiment of the present application, such as Figure 6 As shown, the method includes: S1, performing sputtering, deposition or evaporation treatment on one surface of the obtained substrate layer to form a dual-gate metal electrode; S2, performing oxidation and deposition treatment on the surface of the substrate layer on which the dual-gate metal electrode is prepared to form an insulating dielectric layer; S3, transferring graphene to a side of the insulating dielectric layer away from the substrate layer, and patterning the graphene to obtain a graphene layer; S4. Performing photolithography, sputtering, deposition or evaporation treatment on two opposite ends of the graphene layer to form source and drain metal electrodes to obtain the dual-gate controlled graphene micro-nanostructure terahertz detector.

[0033] The specific definition of the preparation method of a dual-gate controlled graphene micro-nano structure terahertz detector can be referred to the above-mentioned definition of a dual-gate controlled graphene micro-nano structure terahertz detector, which will not be repeated here. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0034] A dual-gate regulated graphene micro-nanostructure terahertz detector and its preparation method provided in this embodiment are used to solve the technical problem of how to design a terahertz detector to improve the detection efficiency and adaptability of the terahertz detector. It includes an effective detection layer and a substrate layer; the effective detection layer includes a dual-gate metal electrode, an insulating dielectric layer, a graphene layer and a source-drain metal electrode; the dual-gate metal electrode is coated in the insulating dielectric layer, and the connection surface of the dual-gate metal electrode is in close contact with the substrate layer; the insulating dielectric layer is arranged above the substrate layer; the graphene layer is located above the insulating dielectric layer, and includes a graphene patterned structure array, which is composed of a circular structure subarray or a polygonal structure subarray connected by strips; the dual-gate metal electrode is located in the space where the graphene patterned structure array is mapped on the insulating dielectric layer; the source-drain metal electrode is arranged above the insulating dielectric layer, and the source-drain metal electrode covers the two ends of the graphene patterned structure array respectively, and is electrically connected to the graphene patterned structure array. The dual-gate controllable graphene micro-nanostructure terahertz detector provided in the present application consists of a graphene layer of a patterned structure array, a dual-gate metal electrode, an insulating dielectric layer and a source-drain metal electrode. The Fermi level of the graphene layer can be flexibly controlled by applying an external voltage to the dual-gate metal electrode. It has low loss, supports mid-infrared to terahertz bands, realizes greenhouse response and wide spectrum response, and has high responsiveness, and has good application prospects.

[0035] Each embodiment in this specification is described in a progressive manner, and the parts that are directly the same or similar to each other can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiment, since it is basically similar to the device embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the device embodiment. It should be noted that the various technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, all possible combinations of the various technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0036] The above-mentioned embodiments only express several preferred implementation modes of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principle of the present invention, and these improvements and substitutions should also be regarded as the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the protection scope of the claims.

Claims

1. A dual-gate controlled graphene micro-nanostructure terahertz detector, characterized in that: comprising an effective detection portion layer and a substrate layer; The effective detection layer includes a dual-gate metal electrode, an insulating dielectric layer, a graphene layer and a source-drain metal electrode; The dual-gate metal electrode is coated in the insulating dielectric layer, and the connection surface of the dual-gate metal electrode is in close contact with the substrate layer; The insulating dielectric layer is disposed above the substrate layer; The graphene layer is located above the insulating dielectric layer, and includes a graphene patterned structure array, wherein the graphene patterned structure array is composed of circular structure sub-arrays or polygonal structure sub-arrays connected by strips; The dual-gate metal electrode is partially or completely located in a space where the graphene patterned structure array is mapped on the insulating dielectric layer; The source-drain metal electrodes are arranged above the insulating dielectric layer, and the source-drain metal electrodes respectively cover two ends of the graphene patterned structure array and are electrically connected to the graphene patterned structure array.

2. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The circular diameter of the circular structure subarrays ranges from 0.1 μm to 200 μm, and the width of the corresponding strips connecting the circular structure subarrays ranges from 1 / 10 to 1 / 2 of the circular diameter.

3. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The size range of the polygonal side length of the polygonal structure subarray is 0.1 μm to 200 μm, and the width of the corresponding strip connecting the polygonal structure subarray is 1 / 10 to 1 / 2 of the polygonal side length.

4. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The spacing between adjacent circles of the circular structure subarray is 0.2 μm to 500 μm, and the number of circles is 2 to 100; The distance between adjacent polygons of the polygon structure subarray is 0.2 μm-500 μm, and the number of polygons is 2-100.

5. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The dual gate metal electrode includes two independent gate metal electrodes; The shapes of the source-drain metal electrode and the dual-gate metal electrode are circular within a first size range or polygonal within a second size range; The first size range is a size range of circular diameter of 10 μm to 1000 μm; The second size range is a size range of 10 μm to 1000 μm for the side length of the polygon.

6. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The source-drain metal electrode and the dual-gate metal electrode are single materials of any one of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel; or, the source-drain metal electrode and the dual-gate metal electrode are composite materials composed of at least two of Al, Ag, Au, Bi, Cr, Ti, Ni and ion gel; The insulating dielectric layer is a single material of any one of SiO2, Al2O3, HfO2, Si3N4, MgO, MnO2, h-BN, diamond, mica and polymer material films; or, the insulating dielectric layer is a composite material composed of at least two of SiO2, Al2O3, HfO2, Si3N4, MgO, MnO2, h-BN, diamond, mica and polymer material films.

7. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The thickness of the source-drain metal electrode is greater than the thickness of the graphene layer.

8. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The thickness of the dual-gate metal electrode is smaller than the thickness of the insulating dielectric layer.

9. The dual-gate controlled graphene micro-nanostructure terahertz detector according to claim 1, characterized in that: The thickness of the substrate layer is less than or equal to 1000 μm.

10. A method for preparing a dual-gate controlled graphene micro-nano structure terahertz detector, used for preparing the dual-gate controlled graphene micro-nano structure terahertz detector as claimed in any one of claims 1 to 9, characterized in that: The preparation method comprises: Performing sputtering, deposition or evaporation treatment on one surface of the obtained substrate layer to form a double gate metal electrode; Performing oxidation and deposition treatment on the surface of the substrate layer on which the dual-gate metal electrode is prepared to form an insulating dielectric layer; Transferring graphene to a side of the insulating dielectric layer away from the substrate layer, and patterning the graphene to obtain a graphene layer; Photolithography, sputtering, deposition or evaporation treatment is performed on two opposite ends of the graphene layer to form source and drain metal electrodes to obtain the double-gate controlled graphene micro-nanostructure terahertz detector.

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