CN120529679A

CN120529679A - Ga2O3/Bi2Te3 lateral heterojunction photodetector and preparation method thereof

Info

Publication number: CN120529679A
Application number: CN202510658122.8A
Authority: CN
Inventors: 白甜甜; 顾培民
Original assignee: Hangzhou Huarui Xinchuang Technology Co ltd
Current assignee: Hangzhou Huarui Xinchuang Technology Co ltd
Priority date: 2025-05-21
Filing date: 2025-05-21
Publication date: 2025-08-22

Abstract

The scheme provides a Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector and a preparation method thereof, the method comprises the steps of S1, obtaining a Ga ₂O₃ substrate, patterning, photoetching and etching the Ga ₂O₃ substrate to obtain a Ga ₂O₃ active region, S2, depositing a SiO ₂ protective layer on the Ga ₂O₃ active region and patterning the SiO ₂ protective layer to obtain an ion implantation region exposing the surface of the Ga ₂O₃ active region, S3, carrying out single-side Si ion implantation and ion implantation activation annealing on the Ga ₂O₃ active region in the ion implantation region, S4, depositing a first metal electrode on the ion implantation region by utilizing an EBV and stripping technology, carrying out ohmic annealing on the first metal electrode, S5, depositing a Bi ₂Te₃ film on the other side of the Ga ₂O₃ active region relative to the ion implantation region by utilizing a magnetron sputtering and stripping technology, and depositing a second metal electrode on the Bi ₂Te₃ by utilizing an EBV and stripping technology, and the transverse heterojunction photoelectric detector with excellent performances of high photoresponsitivity, high photodetection, low dark current, high response speed and the like is obtained.

Description

Ga 2O3/Bi2Te3 transverse heterojunction photoelectric detector and preparation method thereof

Technical Field

The invention relates to the technical field of wide bandgap compound semiconductors and the field of photoelectric detection, in particular to a Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector and a preparation method thereof.

Background

A photodetector is a special device capable of converting an optical signal into an electrical signal, and its core principle is to convert photon energy into a detectable current or voltage by using an internal photoelectric effect (i.e., photoconductive effect and photovoltaic effect). Currently, the mainstream photodetectors in the market are generally made of semiconductor materials such as silicon (Si), germanium (Ge), indium gallium arsenide (InGaAs), and the like, and the spectral range capable of being effectively detected is mainly concentrated in the visible light and near infrared light bands. With the development of technology, the requirements of ultraviolet photodetectors are increasing, and the mainstream photodetectors cannot meet the detection requirements. Ultraviolet light having a wavelength between 200 and 280nm is hardly present in the near-earth atmosphere due to scattering by the atmosphere, and is therefore called "solar blind ultraviolet light". The solar blind ultraviolet detector has important application value in civil and military fields such as flame detection, electric arc detection, missile wake detection and the like. As a novel wide forbidden band semiconductor material, gallium oxide (Ga ₂O₃) has an ultra-large forbidden band width (about 4.9 eV), has high physical stability and chemical stability, can work in a high-pressure environment, has obvious absorption capacity to solar blind ultraviolet light, and is an ideal preparation material for a solar blind ultraviolet detector.

However, the Ga ₂O₃ ultraviolet detector also has the problems of low responsivity, low response speed, high dark current and the like. The current research mainly solves the problems in the aspects of designing different device structures, optimizing the process flow and the like, and after many years of research, researchers have developed several Ga ₂O₃ photodetectors, such as photoconductive photodetectors, schottky junction photodetectors, pn heterojunction photodetectors and the like, wherein the pn heterojunction Ga ₂O₃ photodetectors form built-in electric fields through the contact of semiconductors of different conductivity types so as to promote the separation of photon-generated carriers, and the device has high sensitivity, high response speed and high quantum efficiency, and is one of the detector structures with optimal performance.

The majority of the p-type heterojunction Ga ₂O₃ photoelectric detectors reported at present mainly adopt sol-gel method, chemical Vapor Deposition (CVD), electron beam Evaporation (EBV) and other methods to prepare p-type materials, however, the methods have the large limitations that the process period of the sol-gel method is long, the steps of drying and heat treatment after gel are complicated, the precursor raw material cost is high, the process control is very complex, the tiny fluctuation of the reaction conditions easily causes the performance difference of devices in different batches, the repeatability is influenced, the large-scale market preparation is difficult, the CVD method has high reaction temperature, the high temperature process easily causes the damage of a substrate or a material structure, the deposition rate is very low, the gas source participating in the deposition reaction and the residual gas after the reaction have certain toxicity and have certain potential safety hazards, the film deposited by the EBV method has weak adhesion with a substrate, the film component proportion is easily separated in the subsequent process steps, the high temperature process easily volatilizes the low-melting point component in the multielement material, and the film component proportion is easily disordered, and the conductivity is influenced.

In addition, most of the current photodetectors adopt a vertical heterojunction structure, the preparation process of the vertical heterojunction structure is complex, vertical stacking among different materials, especially alignment of atomic pole thickness materials (such as two-dimensional materials), is required to be accurately controlled, so that the process difficulty is high, interface defects are generated by the different materials of the vertical stacking due to the difference of lattice constants, a carrier recombination center is increased, and a device has larger dark current.

Therefore, a method with simple operation, high efficiency and low cost is needed to prepare the pn heterojunction Ga ₂O₃ photoelectric detector with the characteristics of high light responsivity, quick response time and low dark current.

Disclosure of Invention

The invention aims to provide a Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector and a preparation method thereof, wherein a Bi ₂Te₃ film is deposited on the surface of Ga ₂O₃ by utilizing a magnetron sputtering method to form a transverse heterojunction interface, so that the pn transverse heterojunction photoelectric detector with excellent performances such as high light responsivity, high light detection degree, low dark current, high response speed and the like is obtained.

In order to achieve the above purpose, the present technical solution provides a method for preparing a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photoelectric detector, including the following steps:

S1, acquiring a Ga ₂O₃ substrate, and patterning, photoetching and etching the Ga ₂O₃ substrate to obtain a Ga ₂O₃ active region;

S2, depositing a SiO ₂ protective layer on the Ga ₂O₃ active region and patterning the SiO ₂ protective layer to obtain an ion implantation region exposing the surface of the Ga ₂O₃ active region;

s3, single-side Si ion implantation is carried out on the Ga ₂O₃ active region in the ion implantation region, and ion implantation activation annealing is carried out;

s4, depositing a first metal electrode on the ion implantation area by utilizing an EBV and stripping technology, and carrying out ohmic annealing on the first metal electrode;

S5, depositing a Bi ₂Te₃ film on the other side of the Ga ₂O₃ active region opposite to the ion implantation region by using a magnetron sputtering and stripping technology, and depositing a second metal electrode on the Bi ₂Te₃ by using an EBV and stripping technology.

In a second aspect, the present technical solution provides a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector, including:

Forming at least one Ga ₂O₃ substrate with Ga ₂O₃ channel, and injecting Si ions on one side in the ion injection area of the Ga ₂O₃ channel;

A first metal electrode deposited on the ion implantation region of the Ga ₂O₃ channel;

A Bi ₂Te₃ thin film formed on the opposite side of the ion implantation region of the Ga ₂O₃ channel by magnetron sputtering;

A second metal electrode deposited on the Bi ₂Te₃ film.

Compared with the prior art, the technical scheme has the following characteristics and beneficial effects:

The method comprises the steps of firstly patterning a Ga ₂O₃ substrate, photoetching and etching to obtain Ga ₂O₃ active areas with different lengths and widths, performing Si ion implantation and activation annealing after implantation on one side of the Ga ₂O₃ active area, photoetching to obtain a first metal electrode, depositing the first metal electrode on Ga ₂O₃ of an ion implantation area by utilizing an EBV and stripping technology, performing ohmic annealing on the first metal electrode to enable the first metal electrode to form ohmic contact with Ga ₂O₃, photoetching to obtain a Bi ₂Te₃ area, depositing a Bi ₂Te₃ film on the other side of the Ga ₂O₃ active area by utilizing a magnetron sputtering and stripping technology, depositing a second metal electrode on Bi ₂Te₃ by utilizing the same method to obtain the Ga ₂O₃/Bi₂Te₃ heterojunction photoelectric detector. And the transverse heterojunction is easy to process by a photoetching process, supports a high-density photoelectric detector array, has stronger tolerance to mechanical bending, is suitable for an imaging sensing system and is suitable for various flexible electronic equipment.

Drawings

Fig. 1 is a block diagram of a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector after deposition of a first metal electrode.

Fig. 2 is a block diagram of a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector after deposition of a Bi ₂Te₃ film.

Fig. 3 is a block diagram of a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector after deposition of a second metal electrode.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which are derived by a person skilled in the art based on the embodiments of the invention, fall within the scope of protection of the invention.

It will be appreciated by those skilled in the art that in the present disclosure, the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," etc. refer to an orientation or positional relationship based on that shown in the drawings, which is merely for convenience of description and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore the above terms should not be construed as limiting the present invention.

Example 1

The scheme provides a preparation method of a Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector, which comprises the following steps:

and S5, depositing a Bi ₂Te₃ film on the other side of the Ga ₂O₃ active region opposite to the ion implantation region by using a magnetron sputtering and stripping technology, and depositing a second metal electrode on the Bi ₂Te₃ by using an EBV and stripping technology.

According to the scheme, the Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector which takes Bi ₂Te₃ as a p-type material and Ga ₂O₃ as an n-type material is prepared by adopting a transverse heterojunction structure design and an asymmetric doping technology and combining a low-temperature magnetron sputtering process, a strong built-in electric field is generated at an interface of the Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector, the transmission path of photo-generated carriers is shortened, the response speed and the photo-responsivity of the photoelectric detector are obviously improved, the transverse heterojunction is easy to process by a photoetching process, the high-density photoelectric detector array is supported, the mechanical bending tolerance is stronger, the device is applicable to an imaging sensing system, and the device is applicable to various flexible electronic equipment.

Regarding step S1:

And obtaining a high-purity Ga ₂O₃ monocrystal, cleaning and drying the monocrystal to obtain a Ga ₂O₃ substrate, and patterning, photoetching and etching the Ga ₂O₃ substrate to obtain Ga ₂O₃ active regions with different lengths and widths.

In some embodiments, the Ga ₂O₃ single crystal is subjected to ultrasonic cleaning for 5min by acetone, isopropanol and deionized water respectively, and after cleaning, the Ga ₂O₃ substrate is obtained by drying by a nitrogen gun.

Further, acetone and isopropanol are adopted for cleaning, then piranha solution (concentrated H ₂SO₄:H₂O₂ =3:1) is used for cleaning for 30min, and dangling bonds, surface states and stubborn pollution existing on the surface of the substrate are washed off.

In some embodiments, a photoresist is laid on the Ga ₂O₃ substrate, a pre-designed pattern is transferred onto the photoresist by using a photolithography technique, then an unnecessary region is removed by an etching process to form a recessed Ga ₂O₃ active region on the Ga ₂O₃ substrate, when excited by external energy (such as light, an electric field, etc.), ga ₂O₃ material in the Ga ₂O₃ active region can generate electron-hole pairs, and the Ga ₂O₃ active region provides a channel for carriers to be able to move directionally therein, thereby enabling the conversion of an optical signal into an electrical signal to be detected.

In some embodiments, the etched thickness of the Ga ₂O₃ active region is 400-450 nm. In the etching thickness range, the carrier concentration and mobility in the Ga ₂O₃ active region can be well controlled, and the etching thickness of the Ga ₂O₃ active region is preferably 450nm.

In some embodiments, the Ga ₂O₃ substrate is etched using an inductively coupled plasma etching process to obtain a Ga ₂O₃ active region.

Regarding step S2:

In some embodiments, a protective layer of SiO ₂ is deposited on the Ga ₂O₃ active region using PECVD techniques, the protective layer of SiO ₂ serving to protect the impact of subsequent ion implants on the Ga ₂O₃ surface by buffering the energy of the implanted ions to reduce direct damage to the Ga ₂O₃ lattice by the ions.

In some embodiments, the SiO ₂ protective layer is covered with photoresist, a specific pattern is formed after the photoresist is exposed and developed, and the photoresist-unprotected SiO ₂ part is removed by using an etching process, so that the openings which are the same as the photoresist pattern are formed on the SiO ₂ protective layer, and the openings correspond to the areas needing ion implantation, so that ions can only be implanted into the appointed Ga ₂O₃ active region part, and accurate doping control is realized.

In some embodiments, the thickness of the SiO ₂ protective layer is 40-60 nm, which has the advantage of providing a sufficient physical barrier against direct impact of high-energy ions, impurities and mechanical stress on the Ga ₂O₃ surface and facilitating subsequent lift-off. Preferably, the thickness of the SiO ₂ protective layer is 50nm.

In some embodiments, ion implantation regions are located at side positions of the Ga ₂O₃ active region to facilitate ohmic contact between the Ga ₂O₃ and the first metal electrode.

In some embodiments, the ion implantation region exposes a surface of the Ga ₂O₃ active region so that subsequent Si ions can be implanted from the ion implantation region into the Ga ₂O₃ active region.

Regarding step S3:

Ion implantation is a technique of introducing specific ions into a semiconductor material to change its electrical properties, and the present solution bombards the Ga ₂O₃ active region with Si ions, which penetrate the surface of the Ga ₂O₃ material into the lattice and stay at a depth position to achieve implantation. After injecting Si ions into the Ga ₂O₃ active region, si atoms replace part of the atomic positions in the lattice of Ga ₂O₃, and due to the difference between the number of outer electrons of Si atoms and the number of outer electrons of part of atoms in Ga ₂O₃, extra electrons are introduced into the Ga ₂O₃ material, so that the electron concentration in the material is increased, the Ga ₂O₃ active region exhibits n-type conductivity, and further electrical properties, such as conductivity, are improved.

In some embodiments, single-sided Si ion implantation is performed on the Ga ₂O₃ active region in the ion implantation region, and the SiO ₂ layer of the non-ion implantation region may serve as a mask for the ion implantation process.

During ion implantation, the energy of ion implantation can be precisely controlled so that the Si ions have sufficient energy to penetrate the SiO ₂ layer (if any remaining) and reach a depth within the Ga ₂O₃. At the same time, too high ion energies are avoided leading to too deep an implant depth or excessive damage to Ga ₂O₃, and too low energies are avoided leading to ion retention in the SiO ₂ layer. In some embodiments, si ions with different energies are simultaneously and obliquely implanted to perform single-side Si ion implantation on the Ga ₂O₃ active region in the ion implantation region, specifically, the ion implantation dose of the ion implantation is 50keV/5×10 ¹⁴cm^-2、30keV/5×10¹³cm^-2 and 10keV/3×10 ¹⁴cm^-2, and the implantation angle is 7 °.

It should be noted that the present solution adopts multi-energy tilted ion implantation technology, and performs Si ion implantation with a dose combination of 50keV/5×10 ¹⁴cm^-2、30keV/5×10¹³cm^-2 and 10keV/3×10 ¹⁴cm^-2, and an incident angle of 7 °, to form an n ⁺/n graded doped layer with a carrier concentration gradient of 3 orders of magnitude, where the lower energy (10 keV) and relatively higher dose (3×10 ¹⁴/cm²) ion implants are shallower, and can increase the carrier concentration near the surface area, the medium energy (30 keV) and lower dose (5×10 ¹³/cm²) ion implants are slightly deeper, and the high energy (50 keV) and higher dose (5×10 ¹⁴/cm²) ion implants are deepest. The n ⁺/n type graded doped layer is constructed by carrier concentration change of different depths, the space charge region width is expanded, the ultraviolet light absorption efficiency is enhanced, and the performance of the photoelectric detector is improved.

In some embodiments, the Ga ₂O₃ active region is ion implantation activated annealed using rapid annealing (RTP), provided that the temperature is raised at 20 ℃ per second, maintained at 1000 ℃ for 3 minutes under an atmosphere of N ₂.

It should be noted that SiO ₂ is stripped after ion implantation is completed, so that the subsequent first metal electrode is deposited on the surface of the Ga ₂O₃ active region.

Regarding step S4:

And uniformly coating photoresist on the surface of the Ga ₂O₃ active region of the ion implantation region after ion implantation, exposing the ion implantation region corresponding to the first metal electrode pattern through photoetching, exposure and development, depositing a first metal electrode in the ion implantation region by utilizing an electron beam evaporation technology, and removing redundant photoresist.

In some embodiments, the first metal electrode is Ti/Al/Ni and Au deposited from bottom to top, the Ti and Ga ₂O₃ active regions are directly contacted to enhance the bonding force between the whole first metal electrode and Ga ₂O₃ substrate, meanwhile, ti can form better ohmic contact with Ga ₂O₃ to reduce contact resistance, which is beneficial to smooth transmission of current carriers between metal and semiconductor, the electrical property of the device is improved, al is deposited on the Ti and can be used as a main conducting layer to provide a low-resistance transmission path for the current carriers, the resistance of the electrode is effectively reduced, the current transmission efficiency is improved, the Ni is mainly used as a blocking layer, the diffusion of Al to the Ti layer or Ga ₂O₃ active regions is prevented, meanwhile, the diffusion of elements in Ga ₂O₃ to the metal electrode is prevented, the interface characteristics and the device performance of the metal and the semiconductor are prevented from being influenced due to the diffusion of the elements, the Au has extremely high conductivity and chemical stability, the uppermost layer of the first metal electrode is deposited, the resistance of the electrode is further reduced, the electrical property of the electrode is improved, the chemical stability of the Au is good, the metal and the metal layer under the protection can not be corroded by the subsequent metal bonding process, and the subsequent circuit is convenient to operate

In some embodiments, the Ti is 25-35 nm thick, the Al is 100-130 nm thick, the Ni is 40-60 nm thick, and the Au is 40-60 nm thick. Preferably, the Ti thickness is 30nm, the Al thickness is 120nm, the Ni thickness is 50nm, and the Au thickness is 50nm.

In some embodiments, the first metal electrode is ohmic annealed using rapid annealing (RTP) at a ramp rate of 20 ℃ per second, maintained at 490 ℃ under an atmosphere of N ₂, and maintained for 3 minutes.

As shown in fig. 1, fig. 1 is a structural diagram of a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector after depositing a first metal electrode in step S4.

Regarding step S5:

And a Bi ₂Te₃ film is deposited on the other side of the Ga ₂O₃ active region opposite to the ion implantation region by utilizing low-temperature magnetron sputtering, wherein the deposition temperature of the magnetron sputtering is low, the damage of a high-temperature process to the material performance is avoided, the method is suitable for a flexible substrate, the deposition rate reaches 7.5nm/min, and the density and uniformity of the Bi ₂Te₃ film obtained by sputtering are very high.

Specifically, on the area, which is not covered by the SiO ₂ protective layer and is exposed after patterning treatment, of the deposited Ga ₂O₃ active area, the Bi ₂Te₃ film is deposited on the exposed area by utilizing magnetron sputtering, then the redundant photoresist and the Bi ₂Te₃ film on the photoresist are removed by a stripping technology, and the Bi ₂Te₃ film at the specific position on the other side of the ion implantation area of the Ga ₂O₃ active area is left, so that a transverse heterojunction structure is constructed later, and the function of the transverse heterojunction structure in a photoelectric detector is played.

In some embodiments, the DC power of the magnetron sputtering is 7-9W, the temperature is 75-85 ℃, the sputtering rate is 7-8 nm/min, and preferably, the DC power of the magnetron sputtering is 8W, the temperature is 80 ℃, and the sputtering rate is 7.5nm/min.

In some embodiments, the Bi ₂Te₃ film thickness is 80-120 nm, preferably the Bi ₂Te₃ film thickness is 100nm.

In some embodiments, the gas for magnetron sputtering is pure argon, the gas flow is 20-40 Sccm, the pressure in the reaction chamber is controlled at 0.3' 0.6Pa, preferably, the gas for magnetron sputtering is pure argon, the gas flow is 30Sccm, and the pressure in the reaction chamber is controlled at 0.5Pa.

Fig. 2 is a block diagram of a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector after deposition of a Bi ₂Te₃ film, where the Bi ₂Te₃ film and the first metal electrode can be seen to be on opposite sides of Ga ₂O₃.

In some embodiments, photoresist is uniformly coated on the surface of the Bi ₂Te₃ film, the area corresponding to the second metal electrode pattern is exposed through photoetching, exposure and development, and the second metal electrode is deposited in the ion implantation area by using an electron beam evaporation technology and the redundant photoresist is removed.

In some embodiments, the second metal electrode is Al, and the scheme firstly proposes an innovative strategy for constructing ohmic contact by adopting the aluminum electrode and the topological insulator Bi ₂Te₃, so that the material selection limit of the traditional metal electrode system is broken through. By utilizing the dirac cone-shaped metal state characteristic of the surface of Bi ₂Te₃ under topological protection, an aluminum electrode is directly coupled with a high-mobility surface state carrier to form a novel ohmic contact mechanism with dominant interface state tunneling. The design abandons the energy band regulation and control path of heavy doping of the traditional relying body material, obviously reduces the contact potential barrier through the surface state-metal synergistic effect, is compatible with low-temperature process conditions, and avoids the thermal degradation risk of the material. The interface engineering strategy provides a new paradigm for low-power consumption electrode design and scale integration of topological insulator-based devices.

Fig. 3 is a block diagram of a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector after deposition of a second metal electrode, it being seen that the Bi ₂Te₃ thin film and the first metal electrode are located on opposite sides of Ga ₂O₃.

In some embodiments, the thickness of the second metal electrode is 80-120 nm, preferably, the thickness of the second metal electrode is 100nm.

It is emphasized again that the Bi ₂Te₃ film is integrated on the opposite side of the ion implantation region of the Ga ₂O₃ active region by low-temperature magnetron sputtering, a strong built-in electric field is built at the hetero-interface, and then a Ga ₂O₃/Bi₂Te₃ lateral heterojunction is built, and the lateral heterojunction structure generates a stronger built-in electric field at the interface, so that the transmission path of photo-generated carriers is shortened, and the response speed and the photo-responsivity of the photoelectric detector are remarkably improved. According to the scheme, the single-side gradient doping and asymmetric heterojunction synergistic effect is utilized to realize the remarkable expansion of the space charge region width, so that the ultraviolet light absorption efficiency is improved, the lattice damage introduced by an ion implantation process is effectively reduced based on the design of an inclined implantation angle, and the dark current level of a device is remarkably lower than that of a traditional symmetrical structure photoelectric detector by combining the inhibition effect of single-side doping on interface defects.

Embodiment two:

As shown in fig. 3, the present solution provides a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photoelectric detector prepared by a method for preparing a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photoelectric detector according to the first embodiment, including:

A second metal electrode deposited on the Bi ₂Te₃ film.

The description of the same embodiment of the Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector described in the second embodiment is not repeated here.

It should be noted that the Ga ₂O₃/Bi₂Te₃ lateral heterojunction photoelectric detector prepared by the method has a high-quality Bi ₂Te₃/Ga₂O₃ heterojunction interface with low defect density, the rectification ratio of the Bi ₂Te₃/Ga₂O₃ heterojunction interface reaches the power of 4 times of 10, the strong built-in electric field generated by the lateral heterojunction interface energy band structure effectively promotes the separation and transportation process of photo-generated carriers, and due to the lateral heterojunction structure, the photo-generated carriers flow along the plane direction, the migration path is short, the recombination probability is low, so that the response speed and the photo-responsivity of the photoelectric detector are greatly improved. Compared with a vertical heterojunction structure, the transverse heterojunction material has stronger tolerance to mechanical bending, is directly difficult to strip, and is suitable for large-scale array preparation. The invention has important application potential and value in the field of solar blind ultraviolet photoelectric detection.

It should be understood by those skilled in the art that the technical features of the above embodiments may be combined in any manner, and for brevity, all of the possible combinations of the technical features of the above embodiments are not described, however, they should be considered as being within the scope of the description provided herein, as long as there is no contradiction between the combinations of the technical features.

The foregoing examples illustrate only a few embodiments of the application, which are described in greater detail and are not to be construed as limiting the scope of the application. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of the application should be assessed as that of the appended claims.

Claims

1. The preparation method of the Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector is characterized by comprising the following steps of:

2. The method of fabricating a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector as claimed in claim 1, wherein a protective layer of SiO ₂ is deposited on the Ga ₂O₃ active region by PECVD technique.

3. The method for manufacturing a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector according to claim 1, wherein single-sided Si ion implantation is performed on the Ga ₂O₃ active region in the ion implantation region by simultaneous oblique implantation of Si ions of different energies.

4. The method of manufacturing a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector as claimed in claim 3, wherein the ion implantation doses are 50keV/5 x 10 ¹⁴cm^-2、30keV/5×10¹³cm^-2 and 10keV/3 x 10 ¹⁴cm^-2, and the implantation angle is 7 °.

5. The method of claim 1, wherein the first metal electrode is Ti/Al/Ni and Au deposited from bottom to top.

6. The method for manufacturing the Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector according to claim 1, wherein the direct current power of magnetron sputtering is 7-9W, the temperature is 75-85 ℃, and the sputtering rate is 7-8 nm/min.

7. The method for manufacturing the Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector according to claim 1, wherein the gas of the magnetron sputtering is pure argon, the gas flow is 20-40 sccm, and the pressure in the reaction chamber is controlled at 0.3' 0.6Pa.

8. The method for manufacturing the Ga ₂O₃/Bi₂Te₃ transverse heterojunction photoelectric detector according to claim 1, wherein the thickness of the Bi ₂Te₃ film is 80-120 nm.

9. The method of fabricating a Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector of claim 1, wherein the second metal electrode is Al.

10. A Ga ₂O₃/Bi₂Te₃ lateral heterojunction photodetector, comprising:

A second metal electrode deposited on the Bi ₂Te₃ film.