Ga 2 O 3 -2D metallic van der Waals heterojunction wide-band polarization photodetector and preparation method thereof

Abstract

The present invention relates to a wide-band photoelectric detection device, and specifically to a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photoelectric detector and a preparation method, which are used to solve the shortcomings of existing gallium oxide material photoelectric detectors, such as large dark current, low polarization sensitivity, and no design consideration for application in the deep ultraviolet polarization field and wide-band detection range. The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photoelectric detector includes a gallium oxide layer and a two-dimensional metallic material layer, wherein the gallium oxide layer and the two-dimensional metallic material layer form a horizontal van der Waals Schottky heterojunction / vertical van der Waals Schottky heterojunction; the gallium oxide layer is a β-Ga2O3 single crystal film / β-Ga2O3 single crystal material. Since Ga2O3 has a wide band gap and is a deep ultraviolet luminescent material, and the two-dimensional metallic material has a zero band gap, the present invention can realize wide-band detection of DUV-MIR. At the same time, the present invention provides a preparation method for the above-mentioned Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photoelectric detector.

Description

Technical Field

[0001] The invention relates to a wide-band photoelectric detection device, and in particular to a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photoelectric detector and a preparation method thereof. Background Art

[0002] In recent years, β-Ga2O3 has received widespread attention as an ultra-wide bandgap (UWBG) semiconductor. It has excellent chemical stability, a quasi-direct bandgap of 4.6-4.9 eV, and a photoresponse peak corresponding to the solar-blind band (250-270 nm). It has important application value in fields such as solar-blind deep ultraviolet detection.

[0003] Although Ga2O3 has a very high absorption coefficient in the solar-blind region, there is a large amount of background radiation in the actual space, and the lack of effective bandpass filtering in the deep ultraviolet band may cause false alarms. β-Ga2O3 has a monoclinic lattice structure, and the anisotropic structure of its (100) or (101) crystal plane can be used to prepare narrow-band deep ultraviolet detection devices that realize polarization characteristics. However, the scattering of deep ultraviolet light by aerosols in the atmosphere can easily cause polarization depolarization, and it is necessary to further reduce the dark current and improve the polarization detection capability of Ga2O3. Although the use of sub-wavelength metal grid modulation can improve polarization sensitivity, this method greatly increases the process complexity of the device.

[0004] In terms of detector structure, metal-semiconductor structure photoelectric devices based on Schottky (SB) barriers have been shown to have a large response and light-to-dark current ratio, but it is difficult to avoid surface damage caused by metal deposition, and the metal's blocking of ultraviolet light is not conducive to improving detection performance.

[0005] On the other hand, facing the increasingly complex forest fire remote sensing, high-voltage corona detection and other military and civilian needs for solar-blind ultraviolet-infrared (IR) wide-spectrum detection, wide-band detection has higher sensitivity and communication accuracy than single-spectrum detection, and it is more practical to achieve deep ultraviolet to mid-infrared (DUV-MIR) wide-band detection on the same system. Due to the weak detection performance and complex electrode structure of quantum well sub-band and inter-band transition or back-to-back NPN dual-color detectors, traditional UV / visible-infrared sensitive material integrated detectors are large in size and difficult to bond or heterogeneously grow.

[0006] Two-dimensional (2D) materials have rich band structures. With their inherent van der Waals (vdW) structures, 2D materials can form hybrid heterostructures with ideal bands through transfer with wide bandgap semiconductors. At present, there have been some reports on hybrid heterojunctions based on Ga2O3-2D. For example, Ga2O3 can form Schottky structure heterojunctions with 2D semimetals such as graphene (Gr) transparent electrodes and platinum diselenide (PtSe2). However, the above work only demonstrates excellent detection capabilities in the deep ultraviolet band, but there has been no design consideration for applications in the deep ultraviolet polarization field and wide-band detection range, and there has been no report on related device arrays. Summary of the invention

[0007] The purpose of the present invention is to solve the shortcomings of existing gallium oxide material photodetectors, such as large dark current, low polarization sensitivity, and no design considerations for application in the deep ultraviolet polarization field and wide-band detection range, and to provide a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector and a preparation method.

[0008] In order to solve the deficiencies of the above-mentioned prior art, the present invention provides the following technical solutions:

[0009] A Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector, which is special in that it comprises a dielectric substrate, and M detection units arranged on the dielectric substrate and arranged in a row-column matrix, where M is an integer greater than or equal to 1;

[0010] Each of the detection units comprises a gallium oxide electrode, a gallium oxide layer, a two-dimensional metal material layer and a two-dimensional metal material electrode which are sequentially arranged on the top surface of the dielectric substrate in a horizontal direction; a graphene layer is arranged on the top surface of the two-dimensional metal material layer;

[0011] The gallium oxide layer is a β-Ga2O3 single crystal thin film;

[0012] The two-dimensional metal material layer is a single crystal or polycrystalline thin film, and a semi-metallic 1T d Phase preparation of molybdenum ditelluride or semi-metallic tungsten ditelluride or metallic palladium diselenide or metallic platinum diselenide or metallic tellurium diselenide;

[0013] Part of the gallium oxide electrode covers the top surface of the gallium oxide layer, forming an ohmic contact with the gallium oxide layer;

[0014] Part of the two-dimensional metal material layer covers the top surface of the gallium oxide layer and forms a horizontal van der Waals Schottky heterojunction with the gallium oxide layer. The top surface of the two-dimensional metal material layer is completely covered by the graphene layer. A gap is provided between the side wall of the two-dimensional metal material layer, the side wall of the graphene layer and the side wall of the gallium oxide electrode.

[0015] The two-dimensional metal material electrode partially covers the top surface of the graphene layer and forms an ohmic contact with the graphene layer and the two-dimensional metal material layer;

[0016] The top surfaces of the dielectric substrate, the gallium oxide electrode, the gallium oxide layer, the graphene layer and the two-dimensional metal material electrode are covered with a dielectric passivation layer.

[0017] Further, the gallium oxide layer has a thickness of 50 to 350 nm; the two-dimensional metal material layer has a thickness of 20 to 100 nm; the dielectric substrate is an insulating dielectric substrate or a flexible dielectric substrate; the conventional hard substrate is such as SiO2 / Si, sapphire, quartz glass, etc.; the flexible dielectric substrate is such as an inorganic flexible substrate mica, polydimethylsiloxane (PDMS), etc.;

[0018] The graphene layer is a single crystal thin film with a thickness of 1 to 3 nm;

[0019] The material of the dielectric passivation layer is h-BN, SiO2, Si3N4, HfO 2、 One of Al2O3 with a thickness of 10 to 30 nm.

[0020] Furthermore, the gallium oxide electrode includes a first bottom contact metal and a first top metal, the first bottom contact metal is made of Ti with a thickness of 50 to 100 nm; the first top metal is Au with a thickness of 100 to 300 nm;

[0021] The two-dimensional metal material electrode includes a second bottom contact metal and a second top metal, wherein the second bottom contact metal is made of Cr or Ti with a thickness of 5 to 30 nm; the second top metal is made of Au with a thickness of 60 to 100 nm;

[0022] The distance between the gallium oxide electrode and the two-dimensional metal material electrode is greater than 2 μm.

[0023] Further, the gallium oxide electrodes of at least one column of the M detection units are connected, and / or the two-dimensional metal material electrodes of at least one column of the M detection units are connected.

[0024] A method for preparing the above-mentioned Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector is special in that it comprises the following steps:

[0025] Step 1, cleaning the dielectric substrate;

[0026] Step 2: Transfer and adhere the flexibly prepared or peeled β-Ga2O3 single crystal film to the top surface of the dielectric substrate; use contact photolithography or a hard mask method to pattern the β-Ga2O3 single crystal film, and etch the β-Ga2O3 single crystal film to obtain a gallium oxide layer;

[0027] Step 3: forming a gallium oxide electrode pattern on the dielectric substrate and the gallium oxide layer by photolithography, obtaining a gallium oxide electrode by evaporation on the gallium oxide electrode pattern, and then annealing to form an ohmic contact between the gallium oxide electrode and the gallium oxide layer;

[0028] Step 4: prepare a graphene layer and a two-dimensional metal material layer respectively, peel off the prepared graphene layer and transfer it to the top surface of the two-dimensional metal material layer, then pattern the graphene layer and the two-dimensional metal material layer by photolithography, and then etch the graphene layer and the two-dimensional metal material layer to realize a pattern array;

[0029] The two-dimensional metal material layer covered by the graphene layer is transferred to the dielectric substrate by a wet method or a dry method, and partially overlaps with the gallium oxide layer to form a horizontal Schottky heterojunction;

[0030] Step 5: forming a two-dimensional metal material electrode pattern on the dielectric substrate and the graphene layer by photolithography, and obtaining a two-dimensional metal material electrode by evaporation on the two-dimensional metal material electrode array pattern;

[0031] Step 6: grow or transfer a dielectric passivation layer to the overall top surface formed in step 5.

[0032] At the same time, the present invention also provides a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector, which is special in that it includes a gallium oxide layer, a gallium oxide bottom electrode, a gallium oxide electrode, and N detection units arranged on the gallium oxide layer and arranged in a row-column matrix, where N is an integer greater than or equal to 1;

[0033] The gallium oxide layer is a β-Ga2O3 single crystal material;

[0034] The gallium oxide bottom electrode covers the bottom surface of the gallium oxide layer (2) and forms a Schottky contact with the gallium oxide layer;

[0035] Each of the detection units comprises a two-dimensional metal material layer, a dielectric isolation layer, a graphene layer and a two-dimensional metal material electrode arranged on the top surface of the gallium oxide layer;

[0036] The two-dimensional metal material layer is a single crystal or polycrystalline thin film, and a semi-metallic 1T d Phase preparation of molybdenum ditelluride or semi-metallic tungsten ditelluride or metallic palladium diselenide or metallic platinum diselenide or metallic tellurium diselenide;

[0037] The gallium oxide layer and the two-dimensional metal material layer form a vertical van der Waals Schottky heterojunction; an annular dielectric isolation layer is arranged on the periphery of the two-dimensional metal material layer, and the side wall of the two-dimensional metal material layer is in contact with the side wall of the dielectric isolation layer, the top surface of the two-dimensional metal material layer is covered with the graphene layer, and the periphery of the graphene layer is covered on the top surface of the dielectric isolation layer;

[0038] Part of the top surface of the dielectric isolation layer and part of the top surface of the graphene layer are both covered with the annular two-dimensional metal material electrode, and the two-dimensional metal material electrode forms an ohmic contact with the two-dimensional metal material layer and the graphene layer;

[0039] The gallium oxide electrode is arranged on the top surface of the gallium oxide layer and is located outside the dielectric isolation layer, a gap is arranged between the gallium oxide electrode and the side wall of the dielectric isolation layer, and the gallium oxide electrode is divided into a vertical part and a horizontal part which are perpendicular to each other;

[0040] The top surfaces of the gallium oxide layer, the graphene layer, the two-dimensional metal material electrode, the gallium oxide electrode, and the dielectric isolation layer are covered with a dielectric passivation layer.

[0041] Furthermore, the gallium oxide layer has a thickness of 0.2 to 1 mm; the two-dimensional metal material layer has a thickness of 20 to 100 nm; the graphene layer is a single crystal film with a thickness of 1 to 3 nm; the dielectric isolation layer is SiO2, HfO 2、 One of Al2O3, with a thickness of 20 to 50 nm; the dielectric passivation layer is h-BN, SiO2, Si3N4, HfO 2、 One of Al2O3 with a thickness of 10 to 30 nm.

[0042] Furthermore, the gallium oxide electrode includes a first bottom contact metal and a first top metal, the first bottom contact metal is made of Ti with a thickness of 50 to 100 nm; the first top metal is Au with a thickness of 100 to 300 nm;

[0043] The two-dimensional metal material electrode includes a second bottom contact metal and a second top metal, wherein the second bottom contact metal is made of Cr or Ti with a thickness of 5 to 30 nm; the second top metal is made of Au with a thickness of 30 to 50 nm;

[0044] The distance between the gallium oxide electrode and the two-dimensional metal material electrode is greater than 20 μm, and the distance between the two-dimensional metal material electrodes of adjacent detection units is greater than 20 μm;

[0045] The gallium oxide bottom electrode includes a third bottom contact metal and a third top metal in contact with the gallium oxide layer. The third bottom contact metal is made of Ni with a thickness of 100-200 nm; the third top metal is Au with a thickness of 100-300 nm.

[0046] Furthermore, the dielectric isolation layers of the N detection units are connected.

[0047] A method for preparing the above-mentioned Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector is special in that it comprises the following steps:

[0048] Step 1, etching and cleaning the gallium oxide layer in sequence;

[0049] Step 2: using contact photolithography or a hard mask method to form a gallium oxide electrode pattern on the gallium oxide layer, and then sequentially performing evaporation and annealing to obtain a gallium oxide electrode;

[0050] Step 3, obtaining a gallium oxide bottom electrode on the bottom surface of the gallium oxide layer by sequentially evaporating and annealing;

[0051] Step 4, forming a dielectric isolation layer pattern on the gallium oxide layer by contact photolithography or a hard mask method, then obtaining the dielectric isolation layer by deposition, and treating the gallium oxide layer after the dielectric isolation layer is deposited by oxygen plasma;

[0052] Step 5: prepare a graphene layer and a two-dimensional metal material layer respectively, peel off the prepared graphene layer and transfer it to the top surface of the two-dimensional metal material layer, then pattern the graphene layer and the two-dimensional metal material layer by photolithography, and then etch the graphene layer and the two-dimensional metal material layer to realize a pattern array;

[0053] Transferring the two-dimensional metal material layer covered by the graphene layer to the gallium oxide layer using a wet method or a dry method to form a vertical Schottky heterojunction with the gallium oxide layer;

[0054] Step 6: forming a two-dimensional metal material electrode pattern on the graphene layer and the dielectric isolation layer by photolithography, and obtaining a two-dimensional metal material electrode by evaporation on the two-dimensional metal material electrode array pattern;

[0055] Step 7: grow or transfer a dielectric passivation layer to the overall top surface formed in step 6.

[0056] Compared with the prior art, the present invention has the following beneficial effects:

[0057] (1) The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector of the present invention comprises a gallium oxide layer and a two-dimensional metallic material layer, wherein the gallium oxide layer and the two-dimensional metallic material layer form a horizontal van der Waals Schottky heterojunction / vertical van der Waals Schottky heterojunction; the gallium oxide layer is a β-Ga2O3 single crystal film / β-Ga2O3 single crystal material; the two-dimensional metallic material is a single crystal or polycrystalline thin film, and a semi-metallic 1T dPhase molybdenum ditelluride or semi-metallic tungsten ditelluride or metallic palladium diselenide or metallic platinum diselenide or metallic tellurium diselenide; since Ga2O3 has a wide band gap and is a deep ultraviolet luminescent material, and the two-dimensional metallic material has a zero band gap, the present invention can realize wide-band detection of DUV-MIR;

[0058] Since β-Ga2O3 and the selected crystalline phase two-dimensional metallic material have an in-plane anisotropic structure, polarized light can be detected, expanding the application of wide-band detectors in non-line-of-sight communications, remote sensing of sea oil spills, and aerospace star detection. Specifically: if the two-dimensional metallic material is a single crystal film, polarization detection of all wide bands of DUV-MIR can be achieved. If the two-dimensional metallic material is a polycrystalline film, polarization detection of only the DUV band can be achieved.

[0059] (2) The preparation method of the Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector of the present invention has the advantages of simple preparation process and easy array integration. The prepared photodetector can improve the solar blind detection performance, reduce the false alarm rate outside the solar blind band, and expand the detection capability to long wavelengths. The present invention can also complete the imaging function in conjunction with the lens combination, the rotating stage and the stepping motor, which is of great significance for improving the versatility of the detection system in the military-civilian integration platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 This is a schematic structural diagram of a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to a first embodiment of the present invention;

[0061] Figure 2 for Figure 1 A top view of

[0062] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0063] Figure 4 This is a flow chart of a method for preparing a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to Embodiment 2 of the present invention;

[0064] Figure 5 This is a schematic diagram of the structure of Embodiment 3 of the present invention;

[0065] Figure 6 for Figure 5 A top view of

[0066] Figure 7 This is a schematic diagram of the structure of Embodiment 4 of the present invention;

[0067] Figure 8This is a flow chart of a method for preparing a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector as described in Embodiment 4 of the present invention.

[0068] The reference numerals are explained as follows: 1- dielectric substrate; 2- gallium oxide layer; 3- two-dimensional metal material layer; 4- graphene layer; 5- gallium oxide electrode; 6- two-dimensional metal material electrode; 7- gallium oxide bottom electrode; 8- dielectric isolation layer; 9- dielectric passivation layer. DETAILED DESCRIPTION

[0069] The present invention will be further described below in conjunction with the accompanying drawings and exemplary embodiments.

[0070] Embodiment 1

[0071] Reference Figure 1 , Figure 2 A Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector comprises a dielectric substrate 1, and M detection units arranged on the dielectric substrate 1 and arranged in a row-column matrix, where M is an integer greater than or equal to 1; in this embodiment, M=1.

[0072] Each detection unit includes a gallium oxide electrode 5, a gallium oxide layer 2, a two-dimensional metal material layer 3 and a two-dimensional metal material electrode 6 which are arranged in sequence on the top surface of a dielectric substrate 1 along a horizontal direction; a graphene layer 4 is arranged on the top surface of the two-dimensional metal material layer 3.

[0073] Part of the gallium oxide electrode 5 covers the top surface of the gallium oxide layer 2 , and forms an ohmic contact with the gallium oxide layer 2 .

[0074] Part of the two-dimensional metal material layer 3 covers the top surface of the gallium oxide layer 2 and forms a horizontal van der Waals Schottky heterojunction with the gallium oxide layer 2. The top surface of the two-dimensional metal material layer 3 is completely covered by the graphene layer 4. A gap is set between the side wall of the two-dimensional metal material layer 3, the side wall of the graphene layer 4 and the side wall of the gallium oxide electrode 5.

[0075] Part of the two-dimensional metal material electrode 6 covers the top surface of the graphene layer 4 and forms an ohmic contact with the graphene layer 4 and the two-dimensional metal material layer 3 .

[0076] The top surfaces of the dielectric substrate 1 , the gallium oxide layer 2 , the gallium oxide electrode 5 , the graphene layer 4 and the two-dimensional metal material electrode 6 are covered with a dielectric passivation layer 9 .

[0077] The dielectric substrate 1 is a single crystal Si material and an oxide dielectric material grown on the surface thereof, and the thickness of the oxide dielectric material is 30-300 nm.

[0078] The gallium oxide layer 2 is a β-Ga2O3 single crystal thin film which is unintentionally doped or doped with any one of Si, Ge and Sn. The thickness of the gallium oxide layer 2 is 50-350 nm.

[0079] The two-dimensional metal material layer 3 is a single crystal or polycrystalline film, which meets the conditions of near zero bandgap and can realize visible light-near infrared or visible light-mid-infrared light detection. d The two-dimensional metal material layer 3 is prepared from molybdenum ditelluride, semi-metallic tungsten ditelluride, metallic palladium diselenide, metallic platinum diselenide or metallic tellurium diselenide; the thickness of the two-dimensional metal material layer 3 is 20 to 100 nm.

[0080] The gallium oxide electrode 5 includes a first bottom contact metal and a first top metal. The first bottom contact metal is made of Ti with a thickness of 50-100 nm; the first top metal is Au with a thickness of 100-300 nm.

[0081] The two-dimensional metal material electrode 6 includes a second bottom contact metal and a second top metal. The second bottom contact metal is made of Cr or Ti with a thickness of 5 to 30 nm. The second top metal is made of Au with a thickness of 60 to 100 nm.

[0082] The distance between the gallium oxide electrode 5 and the two-dimensional metal material electrode 6 is greater than 2 μm.

[0083] The graphene layer 4 is a single crystal thin film with a thickness of 1 to 3 nm.

[0084] The material of the dielectric passivation layer 9 is h-BN, SiO2, Si3N4, HfO 2、 One of Al2O3 with a thickness of 10 to 30 nm.

[0085] Embodiment 2

[0086] Reference Figure 3 In this embodiment, M=16; the 16 detection units are arranged in a 4×4 row-column matrix, and the spacing between adjacent rows and adjacent columns is greater than 20 μm.

[0087] In order to save wiring and chip space, the gallium oxide electrodes 5 of two columns of detection units in the 16 detection units are connected, and the two-dimensional metal material electrodes 6 of two columns of detection units in the 16 detection units are connected. It can also be designed as other array forms. The larger the array scale, the wider the detection area. If the actual wiring space allows, other common electrode methods can also be used.

[0088] The rest of the configuration of this embodiment is the same as that of the first embodiment.

[0089] Reference Figure 4A method for preparing a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to embodiment 2 comprises the following steps:

[0090] Step 1, cleaning the dielectric substrate;

[0091] The dielectric substrate 1 is ultrasonically cleaned for 5 to 10 minutes using acetone, isopropanol, and deionized water respectively, and then treated for 3 to 5 minutes using a plasma cleaner with O2 100 sccm 250W;

[0092] Step 2, preparing a gallium oxide layer 2;

[0093] Step 2.1, transferring and adhering the β-Ga2O3 single crystal film prepared by flexible preparation or H ion knife peeling to the top surface of the dielectric substrate 1;

[0094] Step 2.2: Use contact lithography or hard mask method to pattern the β-Ga2O3 single crystal film, and use ICP (inductively coupled plasma etcher) to perform array etching. Specific parameters: BCl3 / Cl2 etching gas, power is 30~50W / 10~20W, gas flow rate is 10~25sccm / 5~10sccm;

[0095] Step 2.3, after obtaining the β-Ga2O3 single crystal thin film pattern array, use acetone ultrasound for 10 to 15 minutes to remove the etching glue, and then use ICP to etch the patterned β-Ga2O3 single crystal thin film surface again to make its surface roughness less than 0.5nm;

[0096] Step 3, preparing a gallium oxide electrode 5;

[0097] Step 3.1, design and use a contact photolithography method to form a gallium oxide electrode 5 pattern on a dielectric substrate 1 and a gallium oxide layer 2, wherein the thickness of the selected photoresist must be more than 900 μm and the acceleration voltage must be greater than 25 KV; this embodiment uses SF6 / AZ701 photoresist, and its spin coating parameters are 2000-5000 r / min, 200°C 3min / 90°C 1min, exposure time 10-20s, and development time 50-80s, so that the exposed pattern area is clear and sharp, and after exposure, oxygen plasma treatment O2 100sccm 200W 3-5min is used to remove the residual glue in the pattern exposure area;

[0098] Step 3.2, using a metal evaporation deposition apparatus to sequentially and sequentially evaporate Ti with a thickness of 50 to 100 nm and Au with a thickness of 100 to 300 nm on the pattern of the gallium oxide electrode 5 formed in step 3.1, with an evaporation rate of 0.1 nm / min, and after the evaporation is completed, using acetone ultrasonic peeling for 10 to 15 minutes to obtain the gallium oxide electrode 5;

[0099] Step 3.3, using a rapid annealing furnace to perform rapid annealing at 450-550° C. for 1-2 min, so that the gallium oxide electrode 5 forms an ohmic contact with the gallium oxide layer 2, that is, the preparation of the gallium oxide electrode 5 is completed;

[0100] Step 4, preparing a two-dimensional metal material layer 3 and a graphene layer 4;

[0101] Step 4.1, prepare a graphene layer 4 by CVD, prepare a two-dimensional metal mold material layer 3 by CVD or PVD, peel off the prepared graphene layer 4 and transfer it to the top surface of the two-dimensional metal mold material layer 3; then use a contact photolithography method to realize the patterning of the graphene layer 4 and the two-dimensional metal mold material layer 3, and then use an ICP machine to etch the graphene layer 4 and the two-dimensional metal mold material layer 3 to realize a pattern array; wherein the etching parameters are: SF6 etching gas, power 5 to 20 W, gas flow rate 10 to 25 sccm;

[0102] Step 4.2, spin-coat polymethyl methacrylate (PMMA), polymethyl carbonate (PPC) or the like as a support layer on the graphene layer 4, the thickness of the support layer being 300 to 500 nm, and heat at 80°C for 2 to 5 min, immerse the whole formed by the graphene layer 4, the two-dimensional metal material layer 3, and the support layer in water, and use tweezers to gently lift the edge of the support layer to separate it from the substrate hydrophilically;

[0103] Step 4.3, use the two-dimensional material transfer platform to move XY and the rotation axis θ, align the position and angle of the two-dimensional metal mold material layer 3 covered by the support layer and the graphene layer 4 with the gallium oxide layer 2 and the gallium oxide electrode 5, so that the long axis of the two-dimensional metal mold material layer 3 and the long axis direction of the gallium oxide layer 2 maintain the same angle; then press down and fix, and heat at 80°C for 5 to 10 minutes to form a horizontal Schottky heterojunction array; finally, use acetone to soak at 70°C for 5 to 8 minutes to remove the support layer, and complete the preparation of the two-dimensional metal mold material layer 3 and the graphene layer 4;

[0104] Step 5, preparing a two-dimensional metal material electrode 6;

[0105] Step 5.1, using electron beam lithography to form a two-dimensional metal material electrode 6 array pattern on the dielectric substrate 1 and the graphene layer 4, wherein the thickness of the electron beam photoresist used should be greater than 200nm, the acceleration voltage should not exceed 20KV, the exposure measurement should be less than 200μm / cm2, and the development time should be 10 to 60s, so that the exposure pattern area is clear and sharp;

[0106] Step 5.2, using an electron beam evaporator or a thermal evaporator to sequentially and sequentially evaporate Ti with a thickness of 5 to 30 nm and Au with a thickness of 60 to 100 nm on the two-dimensional metal material electrode 6 array pattern formed in step 5.1, with an evaporation rate of 0.05 nm / min, and after the evaporation is completed, acetone is used for ultrasonic peeling for 5 to 10 minutes to obtain the two-dimensional metal material electrode 6;

[0107] Step 6, growing or transferring a dielectric passivation layer 9 to the overall top surface formed in step 5;

[0108] Using ozone and Hf[N(CH3)2]4 as sources, at a growth temperature of 150-350°C, a HfO2 film with a thickness of 10-30 nm is passivated by the standard atomic layer deposition (ALD) process to cover the overall top surface formed in step 5, thus completing the preparation of the Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector.

[0109] Embodiment 3

[0110] Reference Figure 5 , Figure 6 A Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector and a preparation method thereof, comprising a gallium oxide layer 2, a gallium oxide bottom electrode 7, a gallium oxide electrode 5, and N detection units disposed on the gallium oxide layer 2 and arranged in a row and column matrix, where N is an integer greater than or equal to 1; in this embodiment, M=1.

[0111] The gallium oxide bottom electrode 7 covers the bottom surface of the gallium oxide layer 2 and forms a Schottky contact with the gallium oxide layer 2 .

[0112] Each detection unit includes a two-dimensional metal material layer 3 , a dielectric isolation layer 8 , a graphene layer 4 and a two-dimensional metal material electrode 6 arranged on the top surface of the gallium oxide layer 2 .

[0113] The gallium oxide layer 2 and the two-dimensional metal material layer 3 form a vertical van der Waals Schottky heterojunction; an annular dielectric isolation layer 8 is arranged on the periphery of the two-dimensional metal material layer 3, and the side wall of the two-dimensional metal material layer 3 is in contact with the side wall of the dielectric isolation layer 8, the top surface of the two-dimensional metal material layer 3 is covered with the graphene layer 4, and the periphery of the graphene layer 4 is covered on the top surface of the dielectric isolation layer 8.

[0114] Part of the top surface of the dielectric isolation layer 8 and part of the top surface of the graphene layer 4 are both covered with the annular two-dimensional metal material electrode 6 , and the two-dimensional metal material electrode 6 forms ohmic contact with the two-dimensional metal material layer 3 and the graphene layer 4 .

[0115] The gallium oxide electrode 5 is arranged on the top surface of the gallium oxide layer 2 and is located outside the dielectric isolation layer (8), a gap is arranged between the gallium oxide electrode 5 and the side wall of the dielectric isolation layer (8), and the gallium oxide electrode 5 is divided into a vertical part and a horizontal part which are perpendicular to each other.

[0116] The top surfaces of the gallium oxide layer 2 , the dielectric isolation layer 8 , the two-dimensional metal material electrode 6 , the graphene layer 4 , and the gallium oxide electrode 5 are covered with a dielectric passivation layer 9 .

[0117] The gallium oxide layer 2 is a β-Ga2O3 single crystal material that is unintentionally doped or doped with any one of Si, Ge, and Sn. The gallium oxide layer 2 has a thickness of 0.2 to 1 mm.

[0118] The two-dimensional metal material layer 3 is a single crystal or polycrystalline thin film, using a semi-metal type 1T d The two-dimensional metal material layer 3 is prepared from molybdenum ditelluride, semi-metallic tungsten ditelluride, metallic palladium diselenide, metallic platinum diselenide or metallic tellurium diselenide; the thickness of the two-dimensional metal material layer 3 is 20 to 100 nm.

[0119] The gallium oxide electrode 5 includes a first bottom contact metal and a first top metal. The first bottom contact metal is made of Ti with a thickness of 50-100 nm; the first top metal is Au with a thickness of 100-300 nm.

[0120] The two-dimensional metal material electrode 6 includes a second bottom contact metal and a second top metal. The second bottom contact metal is made of Cr or Ti with a thickness of 5 to 30 nm. The second top metal is made of Au with a thickness of 30 to 50 nm.

[0121] The distance between the gallium oxide electrode 5 and the two-dimensional metal material electrode 6 is greater than 20 μm, and the distance between the two-dimensional metal material electrodes 6 of adjacent detection units is greater than 20 μm.

[0122] The gallium oxide bottom electrode 7 includes a third bottom contact metal and a third top metal in contact with the gallium oxide layer 2. The third bottom contact metal is made of Ni with a thickness of 100-200 nm; the third top metal is Au with a thickness of 100-300 nm.

[0123] The graphene layer 4 is a single crystal thin film with a thickness of 1 to 3 nm.

[0124] The dielectric isolation layer 8 is SiO2, HfO 2、 One of Al2O3 with a thickness of 20 to 50 nm.

[0125] The dielectric passivation layer 9 is h-BN, SiO2, Si3N4, HfO 2、 One of Al2O3 with a thickness of 10 to 30 nm.

[0126] Embodiment 4

[0127] Reference Figure 7 In this embodiment, M=16; the 16 detection units are arranged in a 4×4 row-column matrix, and the spacing between adjacent rows and adjacent columns is greater than 20 μm.

[0128] In order to save wiring and chip space, 16 detection units share the gallium oxide electrode 5, and the dielectric isolation layer 8 of the 16 detection units is connected. It can also be designed in other array forms. The larger the array scale, the wider the detection area. If the actual wiring space allows, other ways of sharing electrodes can also be used.

[0129] The rest of the configuration of this embodiment is the same as that of the first embodiment.

[0130] Reference Figure 8 A method for preparing a Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to a fourth embodiment comprises the following steps:

[0131] Step 1, cleaning the gallium oxide layer 2;

[0132] ICP is used to etch the surface of the gallium oxide layer 2 so that its surface roughness is less than 0.5 nm; then acetone, isopropanol and deionized water are used to clean the gallium oxide layer 2 for 5 to 10 minutes respectively;

[0133] Step 2, preparing a gallium oxide electrode 5;

[0134] Step 2.1, design and use contact photolithography or hard mask method to form a gallium oxide electrode 5 pattern on the gallium oxide layer 2, wherein the photoresist thickness should be greater than 1 μm, so that the exposed pattern area is clear and sharp, and after exposure, use oxygen plasma treatment O2 100 sccm to remove residual glue in the pattern exposure area;

[0135] Step 2.2, using an electron beam evaporator or a thermal evaporator to continuously evaporate Ti with a thickness of 50 to 100 nm and Au with a thickness of 100 to 300 nm on the gallium oxide electrode 5 pattern formed in step 2.1, with an evaporation rate of 0.1 nm / min, and after the evaporation is completed, using acetone ultrasonic peeling for 10 to 15 minutes to obtain the gallium oxide electrode 5;

[0136] Step 2.3, using a rapid annealing furnace to perform rapid annealing at 450-550° C. for 1-2 min, so that the gallium oxide electrode 5 forms an ohmic contact with the gallium oxide layer 2, that is, the preparation of the gallium oxide electrode 5 is completed;

[0137] Step 3, preparing a gallium oxide bottom electrode 7;

[0138] Step 3.1, using an electron beam evaporator or a thermal evaporator to sequentially deposit Ni with a thickness of 100 to 200 nm and Au with a thickness of 100 to 300 nm on the bottom surface of the gallium oxide layer 2, with an evaporation rate of 0.1 nm / min, and after the evaporation is completed, using acetone ultrasonic stripping for 10 to 15 minutes to obtain the gallium oxide bottom electrode 7;

[0139] Step 3.2, using a rapid annealing furnace to perform rapid annealing at 100-200° C. for 1-2 min to optimize the Schottky contact between the gallium oxide bottom electrode 7 and the gallium oxide layer 2, thus completing the preparation of the gallium oxide electrode 5;

[0140] Step 4: preparing a dielectric isolation layer 8;

[0141] Design and use contact lithography or hard mask method to form a dielectric isolation layer 8 pattern on the gallium oxide layer 2; in this embodiment, after the hard mask is attached to the top surface of the gallium oxide layer 2, a magnetron sputtering method is used to grow a dielectric isolation layer 8 with a thickness of 20 to 50 nm, and the sputtering source power is 100 W. After the growth is completed, the hard mask is removed, and an ion cleaning instrument O2 100 sccm 250 W3 to 5 min is used to treat the gallium oxide layer 2 after the dielectric isolation layer 8 is deposited;

[0142] Step 5, preparing a two-dimensional metal material layer 3 and a graphene layer 4;

[0143] Step 5.1, prepare a graphene layer 4 by CVD, prepare a two-dimensional metal material layer 3 by CVD or PVD, peel off the prepared graphene layer 4 and transfer it to the top surface of the two-dimensional metal material layer 3; then use contact lithography or hard mask method to realize the patterning of the graphene layer 4 and the two-dimensional metal material layer 3, and use ICP to etch the surface to realize the pattern array; wherein the etching parameters are: SF6 etching gas, power 5-20W, gas flow rate 10-25sccm;

[0144] Step 5.2, spin-coat polymethyl methacrylate (PMMA), polymethyl carbonate (PPC) or the like as a support layer on the graphene layer 4, the thickness of the support layer being 300 to 500 nm, and heat at 80°C for 2 to 5 min, immerse the whole formed by the graphene layer 4, the two-dimensional metal material layer 3, and the support layer in water, and use tweezers to gently lift the edge of the support layer to separate it from the substrate hydrophilically;

[0145] Step 5.3, use the two-dimensional material transfer platform to move XY and the angle axis θ, align the position and angle of the two-dimensional metal mold material layer 3 covered by the support layer and the graphene layer 4 with the gallium oxide layer 2 and the gallium oxide electrode 5, so that the long axis of the two-dimensional metal mold material layer 3 and the long axis direction of the gallium oxide layer 2 maintain the same angle; and heat at 80°C for 5 to 10 minutes to form a vertical Schottky heterojunction array; finally, use acetone to soak at 70°C for 5 to 8 minutes to remove the support layer, and complete the preparation of the two-dimensional metal mold material layer 3 and the graphene layer 4;

[0146] Step 6, preparing a two-dimensional metal material electrode 6;

[0147] Step 6.1, using electron beam lithography to prepare a two-dimensional metal material electrode 6 pattern on the graphene layer 4 and the dielectric isolation layer 8, wherein the thickness of the electron beam photoresist used should be greater than 200nm, and the acceleration voltage should not exceed 20KV; so that the exposed pattern area is clear and sharp;

[0148] Step 6.2, using an electron beam evaporator or a thermal evaporator to sequentially and sequentially evaporate Ti with a thickness of 5 to 30 nm and Au with a thickness of 30 to 50 nm on the two-dimensional metal material electrode 6 array pattern formed in step 6.1, with an evaporation rate of 0.05 nm / min, and after the evaporation is completed, using acetone ultrasonic peeling for 5 to 10 minutes to obtain the two-dimensional metal material electrode 6;

[0149] Step 7, growing or transferring a dielectric passivation layer 9 to the overall top surface formed in step 6;

[0150] Using ozone and Hf[N(CH3)2]4 as sources, at a growth temperature of 150-350°C, a HfO2 film with a thickness of 10-30 nm is passivated by the standard atomic layer deposition (ALD) process to cover the overall top surface formed in step 6, thereby completing the preparation of the Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector.

[0151] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. For ordinary professional and technical personnel in the field, the specific technical solutions recorded in the aforementioned embodiments can be modified, or some of the technical features therein can be replaced by equivalents, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions protected by the present invention.

Claims

1. A Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector, characterized in that: It comprises a dielectric substrate (1), and M detection units arranged on the dielectric substrate (1) and arranged in a row-column matrix, where M is an integer greater than or equal to 1; Each of the detection units comprises a gallium oxide electrode (5), a gallium oxide layer (2), a two-dimensional metal material layer (3) and a two-dimensional metal material electrode (6) which are arranged in sequence on the top surface of a dielectric substrate (1) in a horizontal direction; a graphene layer (4) is arranged on the top surface of the two-dimensional metal material layer (3); The gallium oxide layer (2) is a β-Ga2O3 single crystal thin film; The two-dimensional metal material layer (3) is a single crystal or polycrystalline thin film, and adopts a semi-metal type 1T d Phase preparation of molybdenum ditelluride or semi-metallic tungsten ditelluride or metallic palladium diselenide or metallic platinum diselenide or metallic tellurium diselenide; Part of the gallium oxide electrode (5) covers the top surface of the gallium oxide layer (2) to form an ohmic contact with the gallium oxide layer (2); The two-dimensional metal material layer (3) partially covers the top surface of the gallium oxide layer (2) and forms a horizontal van der Waals Schottky heterojunction with the gallium oxide layer (2); the top surface of the two-dimensional metal material layer (3) is completely covered by the graphene layer (4); and gaps are provided between the side walls of the two-dimensional metal material layer (3), the side walls of the graphene layer (4) and the side walls of the gallium oxide electrode (5); Part of the two-dimensional metal material electrode (6) covers the top surface of the graphene layer (4), and forms ohmic contact with the graphene layer (4) and the two-dimensional metal material layer (3); The top surfaces of the dielectric substrate (1), the gallium oxide electrode (5), the gallium oxide layer (2), the graphene layer (4) and the two-dimensional metal material electrode (6) are covered with a dielectric passivation layer (9).

2. The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 1, characterized in that: The gallium oxide layer (2) has a thickness of 50 to 350 nm; the two-dimensional metal material layer (3) has a thickness of 20 to 100 nm; the dielectric substrate (1) is an insulating dielectric substrate or a flexible dielectric substrate; The graphene layer (4) is a single crystal thin film with a thickness of 1 to 3 nm; The material of the dielectric passivation layer (9) is h-BN, SiO2, Si3N4, HfO 2、 One of Al2O3 with a thickness of 10 to 30 nm.

3. The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 2, characterized in that: The gallium oxide electrode (5) comprises a first bottom contact metal and a first top metal, wherein the first bottom contact metal is made of Ti and has a thickness of 50 to 100 nm; the first top metal is Au and has a thickness of 100 to 300 nm; The two-dimensional metal material electrode (6) comprises a second bottom contact metal and a second top metal, wherein the second bottom contact metal is made of Cr or Ti and has a thickness of 5 to 30 nm; the second top metal is made of Au and has a thickness of 60 to 100 nm; The distance between the gallium oxide electrode (5) and the two-dimensional metal material electrode (6) is greater than 2 μm.

4. The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 3, characterized in that: The gallium oxide electrodes (5) of at least one column of the M detection units are connected, and / or the two-dimensional metal material electrodes (6) of at least one column of the M detection units are connected.

5. A method for preparing the Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 1, characterized in that: The steps include: Step 1, cleaning the dielectric substrate (1); Step 2: Transfer and adhere the flexibly prepared or peeled β-Ga2O3 single crystal film to the top surface of the dielectric substrate (1); use contact photolithography or a hard mask method to pattern the β-Ga2O3 single crystal film, and etch the β-Ga2O3 single crystal film to obtain a gallium oxide layer (2); Step 3: forming a gallium oxide electrode (5) pattern on the dielectric substrate (1) and the gallium oxide layer (2) by photolithography, obtaining a gallium oxide electrode (5) by evaporation on the gallium oxide electrode (5) pattern, and then annealing to form an ohmic contact between the gallium oxide electrode (5) and the gallium oxide layer (2); Step 4, preparing a graphene layer (4) and a two-dimensional metal mold material layer (3) respectively, peeling off the prepared graphene layer (4) and transferring it to the top surface of the two-dimensional metal mold material layer (3), then patterning the graphene layer (4) and the two-dimensional metal mold material layer (3) by photolithography, and then etching the graphene layer (4) and the two-dimensional metal mold material layer (3) to realize a pattern array; Using a wet method or a dry method, a two-dimensional metal material layer (3) covered by a graphene layer (4) is transferred onto a dielectric substrate (1), and partially overlapped with a gallium oxide layer (2) to form a horizontal Schottky heterojunction; Step 5: forming a two-dimensional metal material electrode (6) pattern on the dielectric substrate (1) and the graphene layer (4) by photolithography, and obtaining a two-dimensional metal material electrode (6) by evaporation on the two-dimensional metal material electrode (6) array pattern; Step 6: growing or transferring a dielectric passivation layer (9) to the overall top surface formed in step 5.

6. A Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector, characterized in that: It comprises a gallium oxide layer (2), a gallium oxide bottom electrode (7), a gallium oxide electrode (5), and N detection units arranged on the gallium oxide layer (2) and arranged in a row-column matrix, where N is an integer greater than or equal to 1; The gallium oxide layer (2) is a β-Ga2O3 single crystal material; The gallium oxide bottom electrode (7) covers the bottom surface of the gallium oxide layer (2) and forms a Schottky contact with the gallium oxide layer (2); Each of the detection units comprises a two-dimensional metal material layer (3) arranged on the top surface of the gallium oxide layer (2), a dielectric isolation layer (8), a graphene layer (4) and a two-dimensional metal material electrode (6); The two-dimensional metal material layer (3) is a single crystal or polycrystalline thin film, and adopts a semi-metal type 1T d Phase preparation of molybdenum ditelluride or semi-metallic tungsten ditelluride or metallic palladium diselenide or metallic platinum diselenide or metallic tellurium diselenide; The gallium oxide layer (2) and the two-dimensional metal material layer (3) form a vertical van der Waals Schottky heterojunction; an annular dielectric isolation layer (8) is arranged on the periphery of the two-dimensional metal material layer (3), and the side wall of the two-dimensional metal material layer (3) is in contact with the side wall of the dielectric isolation layer (8); the top surface of the two-dimensional metal material layer (3) is covered with the graphene layer (4), and the periphery of the graphene layer (4) is covered on the top surface of the dielectric isolation layer (8); Part of the top surface of the dielectric isolation layer (8) and part of the top surface of the graphene layer (4) are both covered with the annular two-dimensional metal material electrode (6), and the two-dimensional metal material electrode (6) forms an ohmic contact with the two-dimensional metal material layer (3) and the graphene layer (4); The gallium oxide electrode (5) is arranged on the top surface of the gallium oxide layer (2) and is located outside the dielectric isolation layer (8); a gap is arranged between the gallium oxide electrode (5) and the side wall of the dielectric isolation layer (8); and the gallium oxide electrode (5) is divided into a vertical part and a horizontal part which are perpendicular to each other; The top surfaces of the gallium oxide layer (2), the graphene layer (4), the gallium oxide electrode (5), the two-dimensional metal material electrode (6), and the dielectric isolation layer (8) are covered with a dielectric passivation layer (9).

7. The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 6, characterized in that: The gallium oxide layer (2) has a thickness of 0.2 to 1 mm; the two-dimensional metal material layer (3) has a thickness of 20 to 100 nm; the graphene layer (4) is a single crystal thin film with a thickness of 1 to 3 nm; the dielectric isolation layer (8) is SiO2, HfO 2、 One of Al2O3, with a thickness of 20 to 50 nm; the dielectric passivation layer (9) is h-BN, SiO2, Si3N4, HfO 2、 One of Al2O3 with a thickness of 10 to 30 nm.

8. The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 7, characterized in that: The gallium oxide electrode (5) comprises a first bottom contact metal and a first top metal, wherein the first bottom contact metal is made of Ti and has a thickness of 50 to 100 nm; the first top metal is Au and has a thickness of 100 to 300 nm; The two-dimensional metal material electrode (6) comprises a second bottom contact metal and a second top metal, wherein the second bottom contact metal is made of Cr or Ti and has a thickness of 5 to 30 nm; the second top metal is made of Au and has a thickness of 30 to 50 nm; The distance between the gallium oxide electrode (5) and the two-dimensional metal material electrode (6) is greater than 20 μm, and the distance between the two-dimensional metal material electrodes (6) of adjacent detection units is greater than 20 μm; The gallium oxide bottom electrode (7) comprises a third bottom contact metal and a third top metal in contact with the gallium oxide layer (2); the third bottom contact metal is made of Ni with a thickness of 100 to 200 nm; the third top metal is Au with a thickness of 100 to 300 nm.

9. The Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 8, characterized in that: The dielectric isolation layers (8) of the N detection units are connected.

10. A method for preparing the Ga2O3-2D metallic van der Waals heterojunction wide-band polarization photodetector according to claim 6, characterized in that: The steps include: Step 1, etching and cleaning the gallium oxide layer (2) in sequence; Step 2: using contact photolithography or a hard mask method to form a gallium oxide electrode (5) pattern on the gallium oxide layer (2), and then sequentially performing evaporation and annealing to obtain the gallium oxide electrode (5); Step 3, obtaining a gallium oxide bottom electrode (7) on the bottom surface of the gallium oxide layer (2) by sequentially vapor deposition and annealing; Step 4: forming a dielectric isolation layer (8) pattern on the gallium oxide layer (2) by contact photolithography or a hard mask method, then obtaining the dielectric isolation layer (8) by deposition, and treating the gallium oxide layer (2) after the dielectric isolation layer (8) is deposited with oxygen plasma; Step 5, preparing a graphene layer (4) and a two-dimensional metal mold material layer (3) respectively, peeling off the prepared graphene layer (4) and transferring it to the top surface of the two-dimensional metal mold material layer (3), then patterning the graphene layer (4) and the two-dimensional metal mold material layer (3) by photolithography, and then etching the graphene layer (4) and the two-dimensional metal mold material layer (3) to realize a pattern array; Using a wet method or a dry method, the two-dimensional metal material layer (3) covered by the graphene layer (4) is transferred onto the gallium oxide layer (2) to form a vertical Schottky heterojunction with the gallium oxide layer (2); Step 6: forming a two-dimensional metal material electrode (6) pattern on the graphene layer (4) and the dielectric isolation layer (8) by photolithography, and obtaining a two-dimensional metal material electrode (6) by evaporation on the two-dimensional metal material electrode (6) array pattern; Step 7: growing or transferring a dielectric passivation layer (9) to the overall top surface formed in step 6.

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