A nitride nanoparticle array growth method and application, photodetector

Abstract

The present invention relates to the technical field of nitride nanoparticle preparation, and provides a method for growing a nitride nanoparticle array, its application, and a photodetector. The present invention utilizes boundary defects of a two-dimensional material etching pattern to provide dangling bonds, and nitride nanoparticles have a low nucleation energy barrier at these locations. The two-dimensional material pattern with nanometer dimensions can ensure that metal atoms and nitrogen atoms reach the boundary of the two-dimensional material etching pattern within the effective migration length, thereby realizing the controllable preparation of nitride nanoparticles. In the photodetector structure, a two-dimensional material-nitride van der Waals heterojunction with a vertical structure is designed, and metal electrodes are respectively located on the two materials. The junction electric field of the van der Waals heterojunction can realize the automatic separation and collection of photogenerated charges, and it can work under zero bias and has self-driven light response capability. The nitride nanoparticle array growth method provides an effective way to prepare highly integrated, highly sensitive, and self-driven photodetectors.

Description

Technical Field

[0001] The present invention relates to the technical field of nitride nanoparticle preparation, and in particular to a nitride nanoparticle array growth method and application, and a photoelectric detector. Background Art

[0002] Nitride materials, due to their matching direct optical bandgap width, show great application potential in the field of solar-blind ultraviolet light detection. In addition, nitrides have strong radiation resistance and chemical / thermal stability, and the corresponding photodetectors can operate in a variety of complex and harsh environments. However, due to the migration rate and effective migration length of the photogenerated carriers in nitride materials, the spacing between the metal electrodes of the device and the effective photosensitive area are usually small; at the same time, the photodetection gain that can be achieved within the effective carrier lifetime of the photogenerated charges is still low, which limits the response capability of nitride-based photodetectors.

[0003] To fabricate multiple nitride-based photodetector pixels and arrays, the complete nitride epitaxial layer must be etched apart to form independent unit structures to avoid crosstalk. However, mainstream dry etching techniques can easily form numerous dangling bonds and water and oxygen adsorption on the nitride etched sidewalls, which serve as photogenerated charge recombination centers, further limiting the photodetector's response characteristics. Furthermore, current photolithography-etching techniques are performed on bulk nitride materials, making it difficult to fabricate nanoscale device units, hindering the integration and resolution of detection and imaging systems. Low-dimensional nitride materials, such as nitride nanoparticles, offer smaller geometric dimensions that can significantly reduce the size of photodetector pixels, enabling higher-density integration. Furthermore, their large surface area can effectively enhance photon absorption and utilization, improving detector response characteristics. Currently reported methods for growing nitride nanoparticles result in random distribution on the substrate, making it impossible to precisely control the growth sites at the nanoscale. These methods are unsuitable for the fabrication of regular device pixel arrays and subsequent photodetection and imaging applications. Therefore, how to achieve the controllable growth of nitride nanoparticle arrays is the key to realizing their photoelectric detection and imaging applications.

[0004] Based on the defects of the current nitride nanoparticle growth method, it is necessary to improve it. Summary of the Invention

[0005] In light of this, the present invention provides a method for growing a nitride nanoparticle array, its application, and a photodetector. The present invention provides a method for growing a nitride nanoparticle array, as well as a photodetector imaging application based on the nitride nanoparticle array. The core of this method is to utilize dangling bonds generated by etching the edges of a two-dimensional material nanopattern as nucleation sites for nitride nanoparticles, enabling controlled nucleation and growth of the array. Furthermore, a self-driven photodetector structure based on a two-dimensional material-nitride van der Waals heterojunction is designed to meet the requirements of high-sensitivity photodetection and imaging applications.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for growing a nitride nanoparticle array, comprising the following steps:

[0008] growing an n-type doped nitride epitaxial layer on the substrate surface;

[0009] growing a two-dimensional material layer on the n-type doped nitride epitaxial layer;

[0010] Performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement;

[0011] Nitride nanoparticles are grown on the edge of the two-dimensional material layer arranged in a nano-array.

[0012] Preferably, performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with nano-array arrangement includes:

[0013] Nanoimprinting is used to form a nano-sized film pattern mask, and combined with reactive ion etching, the pattern is transferred to the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement;

[0014] Alternatively, performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement includes:

[0015] Based on double-beam interference holographic exposure, a nanometer-sized pattern array is formed on the film, and then plasma etching is used to transfer the pattern to the two-dimensional material layer to form a two-dimensional material layer with a nanometer array arrangement.

[0016] Preferably, the nitride nanoparticles are GaN nanoparticles;

[0017] Growing nitride nanoparticles at the edge of a two-dimensional material layer arranged in a nano-array, specifically comprising:

[0018] A substrate with a two-dimensional material layer arranged with nanoarrays is placed in a reaction chamber. A TMGa source is first introduced into the reaction chamber to form Ga metal droplets, which are adsorbed to the edge of the two-dimensional material layer arranged with nanoarrays. After the TMGa source is turned off, NH3 is introduced for a chemical reaction to form a GaN nanoparticle array at the edge of the two-dimensional material layer arranged with nanoarrays.

[0019] Preferably, the n-type doped nitride epitaxial layer is n-Al x Ga 1-x N layers, 0.15 ≥ x ≥ 0.35;

[0020] The n-Al x Ga 1-x The thickness of the N layer is 450~550nm.

[0021] Preferably, the two-dimensional material layer includes any one of a graphene layer, a boron nitride layer and a transition metal dichalcogenide layer.

[0022] Preferably, the n-Al x Ga 1-x The preparation method of the N layer includes:

[0023] n-Al was prepared by metal-organic chemical vapor deposition x Ga 1-x The N layer uses TMAl, TMGa and NH3 as Al source, Ga source and N source respectively, and SiH4 as doping source, and the growth temperature is 1100~1200℃.

[0024] Preferably, the method for preparing the graphene layer includes:

[0025] The graphene layer was prepared by ultra-high temperature chemical vapor deposition, with CH4, H2 and N2 as the C source, reducing gas and carrier gas respectively. The growth temperature was 1150~1200℃, and the flow ratio of CH4, H2 and N2 was (1~2):(10~20):(100~120).

[0026] In a second aspect, the present invention also provides an application of a nitride nanoparticle array prepared by the preparation method in the preparation of a photodetector.

[0027] In a third aspect, the present invention further provides a photodetector, the preparation method of which comprises the following steps:

[0028] According to the method, nitride nanoparticles are grown on the edge of a two-dimensional material layer arranged in a nano-array;

[0029] Prepare a first electrode on the surface of the two-dimensional material layer arranged in the nanoarray;

[0030] A second electrode is prepared on the n-type doped nitride epitaxial layer and between any two adjacent two-dimensional material layers arranged in nanoarrays.

[0031] Preferably, the material of the first electrode includes at least one of Pt, Ti, Ni, and Al;

[0032] The material of the second electrode includes at least one of Ni, Pt, and Au;

[0033] The thickness of the first electrode is 30-100 nm;

[0034] The thickness of the second electrode is 30-100 nm.

[0035] The nitride nanoparticle array growth method and application, and photodetector of the present invention have the following beneficial effects compared to the prior art:

[0036] 1. The present invention's method for growing nitride nanoparticle arrays utilizes dangling bonds at the boundaries of two-dimensional material etch patterns. Nitride nanoparticles have a low nucleation barrier at these locations. Furthermore, the nanometer-sized two-dimensional material pattern ensures that metal atoms and nitrogen atoms can reach the boundaries of the two-dimensional material etch pattern within an effective migration length, thereby achieving controllable preparation of nitride nanoparticles.

[0037] 2. The photodetector of the present invention comprises a first electrode formed on the surface of a two-dimensional material layer arranged in a nanoarray; a second electrode is formed between any two adjacent two-dimensional material layers arranged in nanoarrays. Each group of regularly arranged nitride nanoparticles functions as a single pixel in the photodetector, enabling high-density arrays to realize highly integrated photodetector imaging applications. The photodetector structure employs a vertically structured two-dimensional material-nitride van der Waals heterojunction, with metal electrodes positioned on each of the two materials. The van der Waals heterojunction's junction electric field enables automatic separation and collection of photogenerated charges, enabling operation at zero bias and exhibiting self-driven photoresponse capability. This nitride nanoparticle array growth method provides an effective approach for fabricating highly integrated, highly sensitive, and self-driven photodetectors. Photodetector arrays fabricated using this method will play an important role in harsh / unmanned environments such as fire warning and deep space exploration. The photodetector of the present invention is used for imaging, and the controllable precision of the nitride nanoparticle array is at the nanometer scale. Therefore, in photodetector imaging applications, the product exhibits high integration and high imaging resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0039] Figure 1 Schematic diagram of the process of the nitride nanoparticle array growth method of the present invention;

[0040] Figure 2 Schematic diagram of the structure of the photoelectric detector of the present invention;

[0041] Figure 3 Graph showing the IV characteristics of the photodetector in Example 2 in the light state and dark state. DETAILED DESCRIPTION

[0042] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0043] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0044] In the description of the present invention, it should be understood that the directions or positions indicated by “upper” and the like are based on the directions or positions shown in the accompanying drawings, or are the directions or positions in which the product of the invention is usually placed when in use, or are the directions or positions commonly understood by those skilled in the art. These directions or positions are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0045] The following are detailed descriptions respectively. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments. In addition, in the description of this application, the term "including" means "including but not limited to". Various embodiments of the present invention may be in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be understood as a rigid limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the numbered ranges, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated in this article, it is meant to include any cited numbers (fractions or integers) within the indicated range.

[0046] The present invention provides a method for growing a nitride nanoparticle array, comprising the following steps:

[0047] S1, growing an n-type doped nitride epitaxial layer on the substrate surface;

[0048] S2, growing a two-dimensional material layer on the n-type doped nitride epitaxial layer;

[0049] S3, performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement;

[0050] S4. Growing nitride nanoparticles on the edge of the two-dimensional material layer arranged in the nanoarray.

[0051] The method for growing nitride nanoparticle arrays of the present invention comprises the following steps: Figure 1 As shown in (a), a substrate 1 is provided; Figure 1 As shown in (b), an n-type doped nitride epitaxial layer 2 is grown on the surface of the substrate 1; Figure 1 As shown in (c), a two-dimensional material layer 3 is grown on the n-type doped nitride epitaxial layer 2; Figure 1 As shown in (d), the two-dimensional material layer is subjected to nano-patterning to form a two-dimensional material layer with a nano-array arrangement; Figure 1 As shown in (e), nitride nanoparticles 4 are grown at the edge of the two-dimensional material layer arranged in a nanoarray; the core of the present invention is to use the dangling bonds generated by etching the edges of the two-dimensional material nanopattern as nucleation sites for nitride nanoparticles to achieve controllable nucleation growth of its array.

[0052] In some embodiments, a complete two-dimensional material layer is processed into a nanometer-sized pattern array based on nanofabrication technology, and dangling bonds are formed at the edges of the pattern of the two-dimensional material layer during the processing. Two processing methods are provided. The first method involves performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with a nanometer array arrangement, including: using nanoimprinting to form a nanometer-sized film pattern mask, and combining it with reactive ion etching to transfer the pattern to the two-dimensional material layer to form a two-dimensional material layer with a nanometer array arrangement.

[0053] The second method is to perform nano-patterning on a two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement, including:

[0054] Based on double-beam interference holographic exposure, a nanometer-sized pattern array is formed on the film, and then plasma etching is used to transfer the pattern to the two-dimensional material layer (the two-dimensional array can be achieved through double exposure) to form a two-dimensional material layer with a nanometer array arrangement.

[0055] Specifically, nanoimprint lithography combined with reactive ion etching is an important technology combination for patterning material surfaces in the field of micro-nanofabrication. Its basic principles are explained as follows:

[0056] Nanoimprinting: Based on physical imprinting, a nanoscale pattern template is used to imprint a pattern onto a polymer film on the surface of a two-dimensional material layer under a certain temperature and pressure, causing the film to plastically deform to form a three-dimensional nanoscale film pattern mask. Reactive ion etching: A specific reactive gas is passed through a vacuum chamber, ionized by an RF electric field to form a plasma. The plasma reacts with the surface of the substrate material, and ion bombardment removes the product. Under the protection of the film mask, the film pattern is transferred to the substrate material. The process flow of nanoimprinting combined with reactive ion etching is as follows:

[0057] 1. Template preparation: Nano-pattern templates are made using materials such as silicon and quartz through techniques such as electron beam lithography;

[0058] 2. Photoresist coating: Spin-coat polymethyl methacrylate or other photoresist on the surface of the two-dimensional material layer to control the thickness;

[0059] 3. Alignment imprinting: The template is precisely aligned with the coated two-dimensional material layer, and the imprinting is performed under appropriate temperature and pressure to deform the photoresist and replicate the pattern;

[0060] 4. Demolding: After cooling, the template is separated and the photoresist (such as polymethyl methacrylate (PMMA)) forms a nano-sized pattern;

[0061] 5. Etching equipment preparation: Place the material layer into the vacuum chamber of the etching equipment and check and debug the equipment;

[0062] 6. Introduce etching gas: Select appropriate gas according to the material (for graphene, mixed gases such as oxygen and argon can be used; for transition metal chalcogenides, fluorine-containing gas (such as carbon tetrafluoride) can be used) and accurately control the flow rate;

[0063] 7. Etching process: Turn on the RF power supply to form plasma, control the relevant parameters to achieve two-dimensional material etching, transfer the pattern, reach the predetermined depth, stop ventilation, and turn off the power;

[0064] 8. Subsequent processing: Remove the photoresist by dissolving with a solvent (such as acetone) or plasma ashing to expose the nanometer-sized pattern array.

[0065] In some embodiments, a nanometer-sized pattern array is formed on a film based on dual-beam interference holographic exposure, and then the pattern is transferred to a two-dimensional material layer using plasma etching to form a two-dimensional material layer with a nanometer array arrangement. The main steps include:

[0066] 1. Photoresist coating: Select photoresist according to the characteristics of the 2D material, spin coat on a spin coater to control the thickness; soft bake on a hot plate at 90-120℃ for 1-2 minutes;

[0067] 2. Dual-beam interferometric holographic exposure: Use ultraviolet laser to build an interference optical path; set the exposure dose and time according to the photoresist characteristics and pattern requirements, and expose the photoresist; two-dimensional array patterns require two vertical exposures;

[0068] 3. Development: Select the developer according to the type of photoresist, immerse the exposed sample in the developer, and then rinse with deionized water to terminate the development;

[0069] 4. Pattern transfer (etching): Select a method such as reactive ion etching based on the type of 2D material layer. After setting parameters such as etching gas and power, place the sample into the equipment for etching and pattern transfer.

[0070] 5. Remove photoresist: Use acetone or other degumming solutions to dissolve the residual photoresist, with the help of heating or ultrasound, and finally rinse with deionized water and blow dry with nitrogen.

[0071] In some embodiments, the two-dimensional material layer is nano-patterned to form a two-dimensional material layer arranged in a nano-array, wherein the length of a single two-dimensional material layer arranged in a nano-array is 10~500nm and the width is 10~500nm; the spacing between two adjacent two-dimensional material layers arranged in a nano-array is 50~500nm.

[0072] In some embodiments, nitride nanoparticles are prepared by metal-organic chemical vapor deposition; the two-step preparation process is: first, a metal organic source is pre-passed to form metal droplets; after the metal organic source is turned off, ammonia is passed in to react with the metal droplets under appropriate conditions to grow nitride nanoparticles; the temperature is increased for annealing to improve the crystal quality of the nitride nanoparticles; the edges of the two-dimensional material layer arranged in the nanoarray are rich in unsaturated dangling bonds, which provide low-energy sites for the nucleation of nitride nanoparticles and control the regular arrangement of nitride nanoparticles along the boundaries of their nanopatterns; therefore, the arrangement spacing, unit size, and period of the nitride nanoparticles can be optimized and regulated by the nanopattern of the two-dimensional material layer.

[0073] In some embodiments, the nitride nanoparticles are GaN nanoparticles;

[0074] Growing nitride nanoparticles at the edge of a two-dimensional material layer arranged in a nano-array, specifically comprising:

[0075] A substrate with a two-dimensional material layer arranged with nanoarrays is placed in a reaction chamber. A TMGa source is first introduced into the reaction chamber to form Ga metal droplets, which are adsorbed to the edge of the two-dimensional material layer arranged with nanoarrays. After the TMGa source is turned off, NH3 is introduced for a chemical reaction to form a GaN nanoparticle array at the edge of the two-dimensional material layer arranged with nanoarrays.

[0076] In some embodiments, the n-type doped nitride epitaxial layer is n-Al x Ga 1-x N layer, 0.15≥x≥0.35; n-Al x Ga 1-x The thickness of the N layer is 450~550nm.

[0077] In some embodiments, the two-dimensional material layer includes any one of a graphene layer, a boron nitride layer, and a transition metal dichalcogenide layer.

[0078] In some embodiments, the following two methods can be used to grow a two-dimensional material layer on an n-type doped nitride epitaxial layer. The first method is to grow a two-dimensional material on a catalytic metal Cu foil using chemical vapor deposition, and then transfer it to the n-type doped nitride epitaxial layer by a wet method. The second method is to use an ultra-high temperature chemical vapor deposition system (>1200 degrees Celsius) to directly epitaxially grow a two-dimensional material layer on the n-type doped nitride epitaxial layer.

[0079] In some embodiments, n-Al x Ga 1-x The preparation method of the N layer includes:

[0080] n-Al was prepared by metal-organic chemical vapor deposition x Ga 1-xThe N layer uses TMAl (trimethylaluminum), TMGa (trimethylgallium) and NH3 as Al source, Ga source and N source respectively, and SiH4 as doping source. The growth temperature is 1100~1200℃.

[0081] In some embodiments, the method for preparing a graphene layer includes:

[0082] Graphene layers were prepared using ultra-high temperature chemical vapor deposition (UHTCVD), using CH₄, H₂, and N₂ as the carbon source, reducing gas, and carrier gas, respectively. The growth temperature was 1150-1200°C, and the flow ratio of CH₄, H₂, and N₂ was (1-2):(10-20):(100-120). Thanks to the low migration barrier of metal atoms on the graphene surface, nitride nanoparticles were able to nucleate and grow only at the edges of the nanoarrayed two-dimensional material layer. Furthermore, by precisely controlling the source introduction and reaction times, the diameter of individual nitride nanoparticles was optimized, leaving the central region of the graphene nanopattern exposed.

[0083] In some embodiments, the graphene layer is a single-layer graphene or a double-layer graphene. The thickness of the single-layer graphene is about 0.335 nm. The double-layer graphene is formed by stacking two single-layer graphene layers, and its thickness is about 0.67 nm.

[0084] In some embodiments, the substrate includes any one of a sapphire substrate, a silicon carbide substrate, and a silicon substrate.

[0085] Based on the same inventive concept, the present invention also provides an application of a nitride nanoparticle array prepared by the above preparation method in the preparation of a photodetector.

[0086] Based on the same inventive concept, the present invention also provides a photodetector, the preparation method of which comprises the following steps:

[0087] According to the above method, nitride nanoparticles are grown on the edge of the two-dimensional material layer arranged in a nano-array;

[0088] Prepare a first electrode on the surface of the two-dimensional material layer arranged in the nanoarray;

[0089] A second electrode is prepared on the n-type doped nitride epitaxial layer and between any two adjacent two-dimensional material layers arranged in nanoarrays.

[0090] Specifically, refer to Figure 2As shown, according to the above method, nitride nanoparticles 4 are grown on the edge of a two-dimensional material layer arranged in a nanoarray; a first electrode 5 is prepared on the surface of the two-dimensional material layer arranged in the nanoarray; a second electrode 6 is prepared between any two adjacent two-dimensional material layers arranged in the nanoarray; the two-dimensional material layer arranged in the nanoarray and the nitride nanoparticle array are arranged regularly, and its unit device is a pixel in the array imaging; the basic structure of a single device is an n-type doped nitride epitaxial layer-two-dimensional material layer-nitride quantum dots, forming a van der Waals heterojunction structure, and the device has self-driven working capability; in a single device, the nitride quantum dots serve as an ultraviolet light absorption layer, the two-dimensional material layer such as graphene serves as a carrier transport channel, and the n-type doped nitride epitaxial layer contacts the metal grid electrode (i.e., the second electrode) as an extended channel for grating carrier collection; the second electrode is prepared between two adjacent two-dimensional material layers arranged in the nanoarray by electron beam lithography, serving as an n-electrode shared by the pixel array; and the first electrode is prepared on the surface of a single two-dimensional material layer arranged in the nanoarray surrounded by the nitride nanoparticle unit. The photoelectric detector of the present invention is used for imaging, and the controllable precision of the nitride nanoparticle array is in the nanometer size. Therefore, in the application of photoelectric detector imaging, the product has high integration and high imaging resolution.

[0091] In some embodiments, the preparation of the first electrode by electron beam lithography mainly includes the steps of photoresist coating, exposure, development, metal deposition and stripping.

[0092] In some embodiments, the material of the first electrode 5 includes at least one of Pt, Ti, Ni, and Al.

[0093] In some embodiments, the material of the second electrode 6 includes at least one of Ni, Pt, and Au.

[0094] In some embodiments, the thickness of the first electrode 5 is 30-100 nm.

[0095] In some embodiments, the thickness of the second electrode 6 is 30-100 nm.

[0096] In some embodiments, the first electrode 5 includes a Ni layer and an Au layer stacked in sequence, and the Ni layer contacts the two-dimensional material layer arranged in a nanoarray; the second electrode 6 includes a Ti layer and an Al layer stacked in sequence, and the Ti layer contacts the n-type doped nitride epitaxial layer.

[0097] The core of this invention is the design of a two-dimensional nano-patterned substrate for precisely controlling the nucleation sites and growth characteristics of nitride nanoparticles. Its theoretical basis is the use of dangling bonds at the boundaries of the two-dimensional material etch pattern, where nitride nanoparticles have a low nucleation barrier. Furthermore, the nanometer-sized two-dimensional material pattern ensures that metal atoms and nitrogen atoms reach the boundaries of the two-dimensional material etch pattern within the effective migration length, thereby enabling the controllable preparation of nitride nanoparticles. Each group of regularly arranged nitride nanoparticles can serve as a single pixel in a photodetector, and thus, its high-density array can realize highly integrated photodetector imaging applications. In terms of the photodetector structure, a vertically structured two-dimensional material-nitride van der Waals heterojunction is designed, with metal electrodes located on the two materials. The van der Waals heterojunction's junction electric field enables the automatic separation and collection of photogenerated charges, allowing it to operate at zero bias and exhibit self-driven photoresponse capabilities. This nitride nanoparticle array growth method provides an effective way to prepare highly integrated, highly sensitive and self-driven photodetectors. The photodetector arrays prepared based on this method will play an important role in harsh / unmanned environments such as fire warning and deep space exploration.

[0098] The following further illustrates the nitride nanoparticle array growth method and application, and photodetector of the present application with specific examples. This section further illustrates the content of the present invention in conjunction with specific examples, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means adopted in the examples are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents, methods, and equipment used in the present invention are conventional reagents, methods, and equipment in the art.

[0099] Example 1

[0100] The present invention provides a method for growing a nitride nanoparticle array, comprising the following steps:

[0101] S1. Clean the sapphire substrate in acetone, ethanol, and deionized water for 5 minutes each, blow dry with a nitrogen gun, and then dry in an oven for later use.

[0102] S2. Growing n-Al on the substrate surface x Ga 1-x N layer, x=0.22, n-Al x Ga 1-x The thickness of the N layer is 450nm; the thickness of the n-Al x Ga 1-x The preparation method of the N layer includes: preparing n-Al by metal-organic chemical vapor deposition x Ga 1-xFor the N layer, TMAl, TMGa, and NH3 were used as Al, Ga, and N sources, respectively, and SiH4 was used as the doping source. The growth temperature was 1125°C, and the flow ratio of TMGa to TMAl was 1:6. Specifically, the flow rate of TMAl was 500 sccm, the flow rate of TMGa was 3000 sccm, the flow rate of NH3 was 5000 sccm, and the flow rate of SiH4 was 300 sccm.

[0103] S3, in n-Al x Ga 1-x The preparation method of the N-layer grown graphene layer, the graphene layer (specifically, double-layer graphene) includes:

[0104] The graphene layer was prepared by ultra-high temperature chemical vapor deposition, with CH4, H2 and N2 as the carbon source, reducing gas and carrier gas, respectively. The growth temperature was 1170℃, and the flow ratio of CH4, H2 and N2 was 1:10:100.

[0105] S4. Nano-patterning the graphene layer to form a graphene layer arranged in a nano-array, wherein a single graphene layer arranged in a nano-array has a length of 100 nm and a width of 100 nm, and a spacing between two adjacent graphene layers arranged in a nano-array is 80 nm;

[0106] Specifically, based on double-beam interference holographic exposure, a nanometer-sized pattern array is formed on the film, and then the pattern is transferred to the graphene layer by plasma etching to form a graphene layer with a nanometer array arrangement; the wavelength of the light source is 355 nanometers, and after the laser light source is split and re-focused, a nanometer-scale interference light fringe pattern is formed; the interference spot size can be adjusted by beam expansion, and the period parameter of the fringe pattern can be controlled by the convergent beam angle and the wavelength of the light source; the graphene nano-patterning method first spin-coats an AZ5214 photoresist film with a thickness of 500 nanometers on the complete graphene layer; based on the positive photoresist process, the exposure metering is controlled to 50%, the exposure time is 30 seconds, and the development time is 25 seconds; for Figure 1 The square array nanopattern shown was created by exposing the film twice, in perpendicular directions. After forming the square array nanopattern on the intact graphene, plasma etching was used to transfer the pattern structure to the graphene. The plasma cleaning and etching conditions were: 50% power, air gas, and 10 minutes of etching time. The photoresist pattern mask was then dissolved and removed in acetone, resulting in a graphene layer with a nanopattern arrangement.

[0107] S5. Growing GaN nanoparticles at the edge of the graphene layer arranged in the nanoarray; specifically comprising: placing the substrate on which the graphene layer arranged in the nanoarray is formed in a reaction chamber, first introducing a TMGa source into the reaction chamber to form Ga metal droplets and adsorbing them to the edge of the graphene layer arranged in the nanoarray, the introduction time being 10 seconds; after turning off the TMGa source, introducing NH3 for 10 seconds to carry out a chemical reaction, thereby forming a GaN nanoparticle array at the edge of the graphene layer arranged in the nanoarray.

[0108] Example 2

[0109] This embodiment also provides a photoelectric detector, the preparation method of which includes the following steps:

[0110] S1. Prepare GaN nanoparticles grown on the edge of the graphene layer arranged in a nanoarray according to the method in Example 1;

[0111] S2. preparing a first electrode on the surface of the graphene layer arranged in the nanoarray;

[0112] S3, in n-Al x Ga 1-x A second electrode is prepared on the N layer and between any two adjacent graphene layers arranged in nanoarrays;

[0113] The first electrode includes a Ni layer (30nm thick) and an Au layer (30nm thick) stacked in sequence, and the Ni layer is in contact with the two-dimensional material layer arranged in a nanoarray; the second electrode includes a Ti layer (30nm thick) and an Al layer (50nm thick) stacked in sequence, and the Ti layer is in contact with the n-type doped nitride epitaxial layer.

[0114] Performance Testing

[0115] Figure 3 1 is the IV characteristic curve of the two-dimensional material-nitride van der Waals heterojunction photodetector in Example 2 in the light state and dark state. Figure 3 Middle I light For light state, I dark It is dark state.

[0116] from Figure 3 It can be seen that there is a difference in the current value of the photodetector in Example 2 at zero bias in the light state and the dark state, and the current in the light state is significantly greater than the current in the dark state, indicating that the photodetector can generate current without an external voltage, relying solely on light and the internal built-in electric field, thereby proving its self-driving capability.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for growing a nitride nanoparticle array, characterized in that: The following steps are involved: growing an n-type doped nitride epitaxial layer on the substrate surface; growing a two-dimensional material layer on the n-type doped nitride epitaxial layer; Performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement; Growing nitride nanoparticles at the edge of a two-dimensional material layer arranged in a nano-array; specifically comprising: A substrate with a two-dimensional material layer arranged with nanoarrays is placed in a reaction chamber. A TMGa source is first introduced into the reaction chamber to form Ga metal droplets, which are adsorbed to the edge of the two-dimensional material layer arranged with nanoarrays. After the TMGa source is turned off, NH3 is introduced for a chemical reaction to form a GaN nanoparticle array at the edge of the two-dimensional material layer arranged with nanoarrays.

2. The method for growing a nitride nanoparticle array according to claim 1, wherein: Performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement includes: Nanoimprinting is used to form a nano-sized film pattern mask, and combined with reactive ion etching, the pattern is transferred to the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement; Alternatively, performing nano-patterning on the two-dimensional material layer to form a two-dimensional material layer with a nano-array arrangement includes: Based on double-beam interference holographic exposure, a nanometer-sized pattern array is formed on the film, and then plasma etching is used to transfer the pattern to the two-dimensional material layer to form a two-dimensional material layer with a nanometer array arrangement.

3. The method for growing a nitride nanoparticle array according to claim 1, wherein: The nitride nanoparticles are GaN nanoparticles.

4. The method for growing a nitride nanoparticle array according to claim 1, wherein: The n-type doped nitride epitaxial layer is n-Al x Ga 1-x N layers, 0.15 ≥ x ≥ 0.35; The n-Al x Ga 1-x The thickness of the N layer is 450~550nm.

5. The method for growing a nitride nanoparticle array according to claim 1, wherein: The two-dimensional material layer includes any one of a graphene layer, a boron nitride layer and a transition metal dichalcogenide layer.

6. The method for growing a nitride nanoparticle array according to claim 4, wherein: The n-Al x Ga 1-x The preparation method of the N layer includes: n-Al was prepared by metal-organic chemical vapor deposition x Ga 1-x The N layer uses TMAl, TMGa and NH3 as Al source, Ga source and N source respectively, and SiH4 as doping source, and the growth temperature is 1100~1200℃.

7. The method for growing a nitride nanoparticle array according to claim 5, wherein: The method for preparing the graphene layer comprises: The graphene layer was prepared by ultra-high temperature chemical vapor deposition, with CH4, H2 and N2 as the C source, reducing gas and carrier gas respectively. The growth temperature was 1150~1200℃, and the flow ratio of CH4, H2 and N2 was (1~2):(10~20):(100~120).

8. Use of a nitride nanoparticle array prepared by the growth method according to any one of claims 1 to 7 in preparing a photodetector.

9. A photoelectric detector, characterized in that: The preparation method comprises the following steps: Growing nitride nanoparticles at the edge of a two-dimensional material layer arranged in a nanoarray according to the method of any one of claims 1 to 7; Prepare a first electrode on the surface of the two-dimensional material layer arranged in the nanoarray; A second electrode is prepared on the n-type doped nitride epitaxial layer and between any two adjacent two-dimensional material layers arranged in nanoarrays.

10. The photodetector according to claim 9, wherein The material of the first electrode includes at least one of Pt, Ti, Ni, and Al; The material of the second electrode includes at least one of Ni, Pt, and Au; The thickness of the first electrode is 30-100 nm; The thickness of the second electrode is 30-100 nm.

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