阅读说明：本技术 一种透明导电结构的紫外波段可调光电探测器及其制备方法 (Ultraviolet band adjustable photoelectric detector with transparent conductive structure and preparation method thereof ) 是由 毛明华 谢雅芳 尹以安 于 2021-07-28 设计创作，主要内容包括：本发明属于光电探测技术领域,公开了一种透明导电结构的紫外波段可调光电探测器及其制备方法,所述探测器的结构为依次排布的探测器衬底、石墨烯插入层、第一GaN层、AlGaN层、Ga-(2)O-(3)层、透明导电层,所述石墨烯插入层和透明导电层上设置有电极。有益效果：石墨烯作为插入层,其与GaN层通过范德华力键合,极大地缓解了与蓝宝石衬底的晶格常数失配,降低了位错密度,提高了外延层的生长质量；与常规GaN/AlGaN外延结构制备的光电探测器相比,加入梯状Ga-(2)O-(3)层,一方面Ga-(2)O-(3)层与透明导电层形成肖特基势垒减小暗电流,另一方面梯状Ga-(2)O-(3)层可以有效增大受光面积,配合石墨烯透明导电材料高迁移率特性增大了光电流。(The invention belongs to the technical field of photoelectric detection, and discloses an ultraviolet band adjustable photoelectric detector with a transparent conductive structure and a preparation method thereof 2 O 3 The graphene/transparent conductive layer comprises a layer and a transparent conductive layer, wherein electrodes are arranged on the graphene insertion layer and the transparent conductive layer. Has the advantages that: the graphene is used as an insertion layer and is bonded with the GaN layer through Van der Waals force, so that the lattice constant mismatch with the sapphire substrate is greatly relieved, the dislocation density is reduced, and the growth quality of an epitaxial layer is improved; compared with the photoelectric detector prepared by the conventional GaN/AlGaN epitaxial structure, the added ladderGa in the form of 2 O 3 Layer of Ga on the one hand 2 O 3 The layer and the transparent conductive layer form a Schottky barrier to reduce dark current, and on the other hand, the ladder-shaped Ga 2 O 3 The layer can effectively increase the light receiving area, and the high mobility characteristic of the graphene transparent conductive material is matched to increase the photocurrent.)

1. The ultraviolet band adjustable photoelectric detector with the transparent conductive structure is characterized in that the structure of the detector is a detector substrate, a graphene insertion layer, a first GaN layer, an AlGaN layer and Ga which are sequentially arranged₂O₃The graphene/transparent conductive layer comprises a layer and a transparent conductive layer, wherein electrodes are arranged on the graphene insertion layer and the transparent conductive layer.

2. The ultraviolet band tunable photodetector of claim 1, wherein the transparent conductive layer is a graphene-silver nanowire structure.

3. The ultraviolet band tunable photodetector of claim 1, wherein the detector substrate is a sapphire substrate.

4. Root of herbaceous plantThe UV band tunable photodetector of claim 1, wherein the Ga is in the form of a transparent conductive structure₂O₃The layer is ladder-shaped, and Ga₂O₃Has a crystal structure of beta-Ga₂O₃。

5. The ultraviolet band tunable photodetector of claim 1, wherein the surfaces of the graphene insertion layer and the transparent conductive layer are respectively provided with a first electrode and a second electrode.

6. The ultraviolet band tunable photodetector of claim 1, wherein the wavelength detected by the photodetector is in the ultraviolet band, and when the applied bias voltage is changed, the photodetector detects ultraviolet bands with different wavelengths.

7. The method for manufacturing the ultraviolet band adjustable photoelectric detector with the transparent conductive structure as claimed in any one of claims 1 to 6, comprising the following steps:

step 1, preparing a single-layer graphene insertion layer on metal Cu through a vapor deposition method, removing the metal Cu, and transferring graphene onto a sapphire substrate;

step 2, growing a first GaN layer and an AlGaN layer on the graphene insertion layer through an MOCVD (metal organic chemical vapor deposition) process;

step 3, generating an undoped second GaN layer on the AlGaN layer, and removing an inherent oxide layer of the second GaN layer;

step 4, placing the second GaN layer with the inherent oxide layer removed into a quartz tube furnace, and injecting oxygen at high temperature; processing the pattern into a ladder shape by photoresist definition to obtain ladder-shaped Ga₂O₃A layer;

step 5, in the ladder-shaped Ga₂O₃Transferring graphene-silver nanowire structures on the layer;

and 6, respectively depositing Ti/Au electrodes on the graphene insertion layer and the transparent conducting layer.

8. The method for manufacturing the ultraviolet band-adjustable photoelectric detector with the transparent conductive structure according to claim 6, wherein the method for manufacturing the graphene insertion layer in the step 1 specifically comprises:

growing single-layer graphene on a Cu substrate by a vapor deposition method; placing a Cu substrate for growing single-layer graphene in (NH)₄)₂S₂O₈Standing the solution for 12-24 hours to remove the Cu substrate; single layer graphene is transferred to a detector substrate.

9. The method of claim 6, wherein step 4 is performed by using a stepped Ga for the UV wavelength band tunable photodetector with a transparent conductive structure₂O₃The preparation method of the layer specifically comprises the following steps:

preparing a second GaN layer on the AlGaN material by MOCVD, removing the inherent oxide layer in diluted hydrochloric acid aqueous solution, then placing the second GaN layer in a quartz tube furnace, and introducing oxygen at 1000 ℃ to prepare Ga₂O₃Layer, and defining photoetching pattern by using photoresist to prepare ladder-like Ga₂O₃And (3) a layer.

10. The method for manufacturing the ultraviolet band-adjustable photoelectric detector with the transparent conductive structure according to claim 6, wherein the method for manufacturing the graphene-silver nanowire structure in the step 5 specifically comprises:

by wet transfer of stepped Ga₂O₃Placing single layer graphene on the layer; dissolving silver nitrate and polyvinylpyrrolidone (PVP) in an ethylene glycol solution, centrifuging, dripping the diluted silver nanowire on the surface of the single-layer graphene through a dripping method, and air-drying to form the graphene-silver nanowire transparent conductive structure.

Technical Field

The invention relates to the technical field of photoelectric detection, in particular to an ultraviolet band adjustable photoelectric detector with a transparent conductive structure and a preparation method thereof.

Background

At present, ultraviolet light can be divided into far ultraviolet UV-A (315-. For example, in a solar blind area in the atmosphere, radiation of a solar blind ultraviolet band can be detected by using a conduction band tail flame; in the medium ultraviolet region, space-based ultraviolet early warning can be performed; in the far ultraviolet region, ultraviolet detection of near-ground aerial targets can be performed. And the ultraviolet detection can determine the absorption long wave limit according to the forbidden band width of the material, so that the photoelectric detector with the adjustable ultraviolet band can be prepared.

The GaN-based photoelectric detector has a forbidden band width of 3.4eV, high photoelectric conversion efficiency, high saturated electron drift speed, suitability for large-scale integration and performance greatly exceeding that of the traditional ultraviolet photoelectric detector. The photoelectric detection of the AlGaN structure is a natural solar blind material, because the Al component content in the AlxGa1-xN alloy is different, the forbidden bandwidth can be distributed in 3.4-6.2 eV. However, GaN/AlGaN materials cause defects at the interface due to lattice constant and coefficient of thermal expansion mismatch, resulting in large dark current near the interface. When the dark current becomes large, the photodetector will fail during the use process, and the light wave cannot be detected.

The single-layer graphene is a hexagonal atomic arrangement structure, is bonded with nitride through van der Waals force, can effectively relieve lattice constant mismatch, is high in carrier mobility and has strong conductive capability, and the responsivity of a device can be effectively improved. However, defects are easily generated in the process of preparing and transferring the graphene structure, so that the transparent conductive capability of the graphene is reduced, and further the photocurrent is reduced.

Therefore, the structure of the existing photoelectric detector needs to be improved, and the problems of large dark current and poor conductivity in the graphene transfer process caused by lattice constant mismatch of a GaN/AlGaN epitaxial structure are solved.

Disclosure of Invention

The purpose of the invention is: the novel ultraviolet band adjustable photoelectric detection structure with the transparent conductive structure is provided, and the problems that due to lattice constant mismatch of a GaN/AlGaN material, a contact surface is defective, dark current near an interface is enlarged, a photoelectric detector fails, and conductivity is poor in a graphene film transfer process are solved.

In order to achieve the purpose, the invention provides an ultraviolet band adjustable photoelectric detector with a transparent conductive structure, and the structure of the detector is a detector substrate, a graphene insertion layer, a first GaN layer, an AlGaN layer, and Ga which are sequentially arranged₂O₃The graphene/transparent conductive layer comprises a layer and a transparent conductive layer, wherein electrodes are arranged on the graphene insertion layer and the transparent conductive layer.

Further, the transparent conducting layer is of a graphene-silver nanowire structure.

Further, the detector substrate is a sapphire substrate.

Further, the Ga is₂O₃The layer is ladder-shaped, and Ga₂O₃Has a crystal structure of beta-Ga₂O₃。

Furthermore, a first electrode and a second electrode are respectively arranged on the surfaces of the graphene insertion layer and the transparent conducting layer.

Furthermore, the detection wavelength of the photoelectric detector is located in an ultraviolet band, and when the applied bias voltage is changed, the photoelectric detector detects the ultraviolet bands with different wavelengths.

The invention also discloses a preparation method of the ultraviolet band adjustable photoelectric detector with the transparent conductive structure, which comprises the following steps:

step 1, preparing a single-layer graphene insertion layer on metal Cu through a vapor deposition method, removing the metal Cu, and transferring graphene onto a sapphire substrate;

step 2, growing a first GaN layer and an AlGaN layer on the graphene insertion layer through an MOCVD (metal organic chemical vapor deposition) process;

step 3, generating an undoped second GaN layer on the AlGaN layer, and removing an inherent oxide layer of the second GaN layer;

step 4, placing the second GaN layer with the inherent oxide layer removed into a quartz tube furnace, and injecting oxygen at high temperature; processing the pattern into a ladder shape by photoresist definition to obtain ladder-shaped Ga₂O₃A layer;

step 5, transferring the graphene-silver nanowire structure on the ladder-shaped Ga2O3 layer;

and 6, respectively depositing Ti/Au electrodes on the graphene insertion layer and the transparent conducting layer.

Further, the preparation method of the graphene insertion layer in the step 1 specifically comprises the following steps:

growing single-layer graphene on a Cu substrate by a vapor deposition method; placing a Cu substrate for growing single-layer graphene in (NH)₄)₂S₂O₈Standing the solution for 12-24 hours to remove the Cu substrate; single layer graphene is transferred to a detector substrate.

Further, step 4 is carried out by using the stepped Ga₂O₃The preparation method of the layer comprises the following steps:

preparing a second GaN layer on the AlGaN material by MOCVD, removing the inherent oxide layer in diluted hydrochloric acid aqueous solution, then placing the second GaN layer in a quartz tube furnace, and introducing oxygen at 1000 ℃ to prepare Ga₂O₃Layer, and defining photoetching pattern by using photoresist to prepare ladder-like Ga₂O₃And (3) a layer.

Further, the preparation method of the graphene-silver nanowire structure in the step 5 specifically comprises the following steps:

placing single-layer graphene on the stepped Ga2O3 layer by using a wet transfer method; dissolving silver nitrate and polyvinylpyrrolidone (PVP) in an ethylene glycol solution, centrifuging, dripping the diluted silver nanowire on the surface of the single-layer graphene through a dripping method, and air-drying to form the graphene-silver nanowire transparent conductive structure.

Compared with the prior art, the ultraviolet band adjustable photoelectric detector with the transparent conductive structure and the preparation method thereof have the advantages that: the graphene is used as an insertion layer and is bonded with the GaN layer through Van der Waals force, so that the lattice constant mismatch with the sapphire substrate is greatly relieved, the dislocation density is reduced, and the growth quality of an epitaxial layer is improved; compared with the photoelectric detector prepared by the conventional GaN/AlGaN epitaxial structure, the stepped Ga is added₂O₃Layer of Ga on the one hand₂O₃The layer and the transparent conductive layer form a Schottky barrier to reduce dark current, and on the other hand, the ladder-shaped Ga₂O₃The layer can effectively increase the light receiving area, and the photocurrent is increased by matching with the high mobility characteristic of the graphene transparent conductive material; furthermore, the graphene-silver nanowire transparent conductive structure can effectively improve the conductive uniformity of the graphene in the transfer process and improve the responsiveness of the device.

Drawings

FIG. 1 is a schematic diagram of a photodetection structure according to the present invention;

FIG. 2 is a top view of a photodetector structure of the present invention;

FIG. 3 is a schematic illustration of the separation of electron-hole pairs of photo-generated carriers generated by the photodetection structure of the present invention when exposed to ultraviolet light;

FIG. 4 is a diagram showing the band variation after the contact of the gallium oxide/AlGaN/GaN heterostructure in the photodetection structure according to the present invention;

FIG. 5 is a graph of the change in Schottky barrier after biasing the photodetection structure of the present invention;

FIG. 6 is a graph of responsivity at different wavelengths of light as measured by applying the photodetection structure of the present invention with an external bias.

In the figure, 1, a probe substrate; 2. a graphene insertion layer; 3. a first GaN layer; 4. an AlGaN layer; 5. ga₂O₃A layer; 6. a transparent conductive layer; 7. a first electrode; 8. a second electrode; 9. a graphene film; 10. silver nanowire structures.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

Example 1:

referring to the attached drawings 1 and 2, the invention discloses an ultraviolet band adjustable photoelectric detector with a transparent conductive structure, and the structure of the detector is a detector substrate 1, a graphene insertion layer 2, a first GaN layer 3, an AlGaN layer 4 and Ga which are sequentially arranged₂O₃The graphene/transparent conductive layer structure comprises a layer 5 and a transparent conductive layer 6, wherein electrodes are arranged on the graphene insertion layer 2 and the transparent conductive layer 6.

In this embodiment, the transparent conductive layer 6 is a graphene-silver nanowire structure. Referring to the partial enlarged portion of fig. 1, the graphene-silver nanowire structure includes: a graphene film 9 and a silver nanowire structure 10. The hybridization of the graphene and the silver nanowires can effectively reduce the defects generated in the preparation and transfer processes of the graphene, improve the conductivity uniformity of the graphene, and improve the photocurrent and the responsivity of the prepared photoelectric detector.

In the present embodiment, the detector substrate 1 is preferably a sapphire substrate.

In this example, referring to FIG. 2, the Ga₂O₃Layer 5 is stepped and Ga₂O₃Has a crystal structure of beta-Ga₂O₃. The ladder is particularly Ga in planar structures compared to planar thin film structures₂O₃Parallel grooves with inverted trapezoid cross sections are formed in the layer 5 at equal intervals, and the size of each parallel groove is the same. Ladder-like beta-Ga₂O₃The effective light receiving area of the layer is increased, the layer and the transparent conducting layer 6 form a Schottky barrier, and as a plurality of photons participate in the conduction, the response time is short, the quantum efficiency is high, and the barrier is highHigh in degree, can avoid P-type materials in the preparation process and has low preparation cost.

In the present embodiment, the surfaces of the graphene insertion layer 2 and the transparent conductive layer 6 are respectively provided with a first electrode 7 and a second electrode 8. The first electrode 7 and the second electrode 8 are used for connecting with an applied bias voltage.

The working principle of the photoelectric detection structure of the invention is as follows:

in this example, the Ga₂O₃The layer 5 and the graphene transparent conductive layer 6 form a Schottky barrier, Ga₂O₃Has an electron affinity smaller than the work function, Ga, of the graphene transparent conductive layer 6₂O₃Volatile side to remove electrons, easy to obtain electrons on the side of the graphene film 9, and in Ga₂O₃One side will form a positively charged immovable depletion region. Referring to fig. 3, when ultraviolet light is irradiated, a large number of electron-hole photo-generated carrier pairs are generated, and are rapidly separated under the action of an internal electric field, and a high-mobility conductive channel is formed through graphene to generate a photocurrent signal.

AlGaN material having a Fermi level greater than Ga₂O₃Materials and GaN materials, therefore AlGaN volatile electrons are bent upwards at both contact surfaces, and at this time the built-in electric field formed by the two contact surfaces is reversed, as shown in fig. 4. When subjected to an external bias, the equilibrium state is destroyed to produce a quasi-Fermi level, resulting in Ga₂O₃One band is raised and one band is lowered at the AlGaN contact surface and the GaN contact surface, thereby forming an energy band structure diagram of fig. 5.

By applying the photoelectric detection structure of the invention, the width of the depletion region can be gradually expanded along with the increase of an external bias, and under the condition of no bias or small bias, the response waveband of ultraviolet light, namely the absorption layer of the photoelectric detection structure is positioned in Ga₂O₃Within the structure, i.e. around 255nm in UV-C, a cut-off will occur. When the applied bias is further increased, the depletion region width is expanded to the AlGaN layer 4, and the light absorption layer is formed from the original Ga₂O₃Layer 5 is converted to AlGaN layer 4 to enable mid-ultraviolet UV-B photodetection. At large bias, of the photodetectorThe depletion layer can move towards the first GaN layer 3, the light absorption layer can fall in a GaN area, the wavelength long wave is limited to be about 364nm, and far ultraviolet UV-A photoelectric detection is realized.

In this embodiment, an implementation manner of the ultraviolet band adjustable photoelectric detection structure of the transparent conductive structure is as follows:

the detector substrate 1 in the present invention is preferably a sapphire substrate, and the thickness of the detector substrate 1 is preferably 2 um.

The graphene insertion layer 2 in the invention is preferably single-layer graphene, and the thickness is preferably 0.01nm-1 mm.

The steps of fabricating the first GaN layer 3 and the AlGaN layer 4 in the present invention are preferably MOCVD fabrication, the thickness of the first GaN layer 3 is preferably 500 μm, the thickness of the AlGaN layer 4 is preferably 200 μm, and the thickness of the second GaN layer is preferably 80 nm.

Example 2:

on the basis of embodiment 1, the invention also discloses a preparation method of the ultraviolet band adjustable photoelectric detection structure of the transparent conductive structure, which is characterized by comprising the following steps:

step 1, preparing a single-layer graphene insertion layer 2 on metal Cu through a vapor deposition method, removing the metal Cu, and transferring graphene onto a sapphire substrate.

And 2, growing a first GaN layer 3 and an AlGaN layer 4 on the graphene insertion layer 2.

And 3, generating an undoped second GaN layer on the AlGaN layer 4, and removing the inherent oxide layer of the second GaN layer.

Step 4, placing the second GaN layer with the inherent oxide layer removed into a quartz tube furnace, and injecting oxygen at high temperature; processing the pattern into a ladder shape by photoresist definition to obtain ladder-shaped Ga₂O₃Layer 5.

Step 5, the ladder-shaped Ga₂O₃The graphene-silver nanowire structure is transferred on layer 5.

And 6, depositing a Ti/Au electrode on the graphene insertion layer 2 and the transparent conducting layer 6.

In step 1, the preparation method of the graphene insertion layer specifically comprises the following steps:

growing single-layer graphene on a Cu substrate by a vapor deposition method; placing a Cu substrate for growing single-layer graphene in (NH)₄)₂S₂O₈Standing for 12-24 hours in the solution to remove the Cu substrate; single layer graphene is transferred onto the detector substrate 1.

In step 2, the method of fabricating the first GaN layer 3 and the AlGaN layer 4 in the present invention is preferably MOCVD fabrication, the thickness of the first GaN layer 3 is preferably 500 μm, and the thickness of AlGaN is preferably 200 μm.

In step 3, the second GaN layer is preferably prepared by MOCVD, and the undoped second GaN layer is preferably 80 nm. The method for removing the intrinsic oxide layer of the second GaN layer specifically comprises the following steps: the second GaN layer was immersed in a dilute aqueous hydrochloric acid solution (HCl: H)₂O) for 5 minutes to remove the native oxide layer.

In the step 4, the second GaN layer with the inherent oxide layer removed is placed into a quartz tube furnace, the treatment is carried out for ten minutes under the temperature condition of 1000 ℃, and 50 milliliters of oxygen is injected into the quartz tube furnace per minute; in Ga₂O₃Layer 5 is patterned with a photoresist definition and lithographically patterned to form a ladder structure.

The ladder-shaped Ga₂O₃The preparation method of the layer specifically comprises the following steps:

preparing a second GaN layer on the AlGaN material by MOCVD, removing the inherent oxide layer in diluted hydrochloric acid aqueous solution, then placing the second GaN layer in a quartz tube furnace, and introducing oxygen at 1000 ℃ to prepare Ga₂O₃Layer, and defining photoetching pattern by using photoresist to prepare ladder-like Ga₂O₃And (3) a layer.

In step 5, the ladder-shaped Ga₂O₃The structure of the transfer graphene-silver nanowire on the layer 5 is specifically as follows:

by wet transfer of stepped Ga₂O₃Placing single layer graphene on the layer; dissolving silver nitrate and polyvinylpyrrolidone (PVP) in an ethylene glycol solution, centrifuging, dripping the diluted silver nanowire on the surface of the single-layer graphene through a dripping method, and air-drying to form the graphene-silver nanowire transparent conductive structure.

The step 5 is more specifically performed by the following steps:

step A: preparing silver nanowires: adding a small amount of silver nitrate AgNO₃And polyvinylpyrrolidone PVP at a ratio of 2: 1 is dissolved in 5mL of glycol solution, 20mL of glycol solution is added after the glycol solution is completely dissolved, and the temperature is kept at 150 ℃; after 80min of reaction, centrifugation was carried out to remove the supernatant, washing with deionized water for 2 times, and PVP was removed.

And B: preparing a graphene film 9: growing graphene on a Cu foil by chemical vapor deposition, and introducing H at the constant temperature of 1000 DEG C₂And Ar gas, annealing for 30min, and introducing methane CH₄As a gaseous carbon source, CH was turned off after 10min of growth₄A channel, which is cooled to form graphene; and (3) placing the Cu foil with the graphene structure in sodium persulfate corrosive liquid for corrosion for 20min, and then placing the Cu foil in deionized water for standing for 30min to obtain the single-layer graphene.

And C: transfer of monolayer graphene to Ga by wet transfer method₂O₃A ladder-like structure.

Step D: diluting the silver nanowires by deionized water, wherein the dilution rate is preferably 200 times;

step E: and dropping the diluted silver nanowire solution on the surface of the graphene, dropping and coating 20 mu L of the diluted silver nanowire solution, and naturally drying to obtain the graphene-silver nanowire structure.

In step 6, the preparation method further comprises a method for manufacturing the first electrode 7 and the second electrode 8: and respectively depositing metal Ti/Au electrodes on the surfaces of the graphene-silver nanowire film and the graphene insertion layer 2 by using a mask and a radio frequency magnetron sputtering technology at room temperature to serve as measuring electrodes. Wherein, the sputtering filling gas is Ar gas, the working pressure is 0.8Pa, the sputtering time of the Ti layer is 30s, and the sputtering time of the Au layer is 70 s. The electrode formed by the graphene insertion layer 2 is a first electrode 7, and the electrode formed on the graphene-silver nanowire structure is a second electrode 8.

As shown in fig. 6, under the condition of applying a small bias voltage, wavelength cut-off occurs around 255nm and 305nm, and under the influence of the graphene film 9, the responsivity is higher than that of the GaN/AlGaN device. Under the condition of large bias voltage, the wavelength cut-off appears around 364nm, and the responsivity is higherThe GaN/AlGaN is obviously improved. And prepared GaN/AlGaN/beta-Ga₂O₃Compared with a GaN/AlGaN-based photoelectric detector, the dark current of the photoelectric detector is reduced by 5 to 6 orders of magnitude, the measured square resistance of the graphene film 9 is 0.3k omega, and the conductivity of the graphene film 9 is improved.

Example 3:

on the basis of the embodiment 1, the invention also discloses an ultraviolet band adjustable photoelectric detector with a transparent conductive structure, and the photoelectric detection structure of the embodiment 1 is applied.

In this embodiment, referring to fig. 5 and fig. 6, the detection band of the photodetector varies with the applied bias voltage, and the photodetector detects ultraviolet light bands with different wavelengths.

Since this embodiment is written based on embodiment 1, the working principle of the photodetection structure is not described in detail.

To sum up, the embodiment of the invention provides a photoelectric detection structure, a photoelectric detector and a preparation method, and the photoelectric detection structure, the photoelectric detector and the preparation method have the advantages that:

1, the sapphire substrate and the first GaN layer 3 have lattice constant mismatch, and the quality of crystal growth is influenced. The graphene is used as the insertion layer to epitaxially grow the gallium nitride layer, the gallium nitride layer is bonded with the nitride through van der Waals force, and the bonding force between the gallium nitride layer and the nitride is weak, so that the stress is greatly released, the influence of lattice mismatch between the sapphire and the GaN layer can be effectively reduced, the generation of dark current is reduced, the heat dissipation can be further enhanced, and the quality of the prepared photoelectric detector is improved.

2, compared with the AlGaN/GaN epitaxial photoelectric detector, the invention adds beta-Ga₂O₃After the layer is formed, a Schottky barrier is formed between the transparent conducting layer 6 and the Schottky barrier, a high-mobility conducting channel is formed under the irradiation of ultraviolet light, and as many photons participate in the conduction, the response time is short, the quantum efficiency is high, the barrier height is high, the P-type material can be avoided in the preparation process, and the preparation cost is low.

3, GaN/AlGaN/beta-Ga based on the structure₂O₃Photodetector by beta-Ga₂O₃Forming a barrier with the transparent conductive layer 6The depletion region is generated by the special contact, and the width of the depletion layer can be correspondingly changed by applying different external bias voltages, so that the main absorption layer is changed, the detection wavelength is changed, and the purpose of selecting the waveband is achieved.

4, the single-layer graphene has high carrier mobility, strong conductivity and good ductility, and electron hole pairs generated by ultraviolet rays in the light absorption layer can be effectively captured by electrons, so that the responsivity of the device can be effectively improved. However, when the graphene is prepared by using a chemical vapor deposition method, defects are easily generated in the preparation and transfer processes, so that the transparent conductivity of the graphene is reduced. By adopting the hybridization of the silver nanowires and the graphene, the resistance of the graphene can be effectively reduced, the conductive uniformity of the graphene film 9 can be effectively improved, and the influence on the light transmittance is small.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.