CN111029435A - ZnGaO ultraviolet detector and preparation method thereof - Google Patents
ZnGaO ultraviolet detector and preparation method thereof Download PDFInfo
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- CN111029435A CN111029435A CN201911266460.8A CN201911266460A CN111029435A CN 111029435 A CN111029435 A CN 111029435A CN 201911266460 A CN201911266460 A CN 201911266460A CN 111029435 A CN111029435 A CN 111029435A
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- 238000002360 preparation method Methods 0.000 title claims description 9
- 239000000463 material Substances 0.000 claims abstract description 53
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 claims abstract description 33
- 229910052733 gallium Inorganic materials 0.000 claims abstract description 30
- 238000000034 method Methods 0.000 claims abstract description 27
- 239000011701 zinc Substances 0.000 claims abstract description 27
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 claims abstract description 26
- 229910052725 zinc Inorganic materials 0.000 claims abstract description 26
- 239000010408 film Substances 0.000 claims description 49
- 239000012159 carrier gas Substances 0.000 claims description 36
- 239000000758 substrate Substances 0.000 claims description 23
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 20
- 229910052751 metal Inorganic materials 0.000 claims description 17
- 239000002184 metal Substances 0.000 claims description 17
- 230000008569 process Effects 0.000 claims description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 14
- 239000001301 oxygen Substances 0.000 claims description 14
- 229910052760 oxygen Inorganic materials 0.000 claims description 14
- 150000002259 gallium compounds Chemical class 0.000 claims description 11
- 229910052757 nitrogen Inorganic materials 0.000 claims description 10
- 150000003752 zinc compounds Chemical class 0.000 claims description 9
- 238000010438 heat treatment Methods 0.000 claims description 8
- 238000010521 absorption reaction Methods 0.000 claims description 7
- 239000010409 thin film Substances 0.000 claims description 7
- 238000005229 chemical vapour deposition Methods 0.000 claims description 6
- 150000002902 organometallic compounds Chemical class 0.000 claims description 6
- 229910052596 spinel Inorganic materials 0.000 claims description 6
- 239000011029 spinel Substances 0.000 claims description 6
- HQWPLXHWEZZGKY-UHFFFAOYSA-N diethylzinc Chemical compound CC[Zn]CC HQWPLXHWEZZGKY-UHFFFAOYSA-N 0.000 claims description 5
- 239000010931 gold Substances 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- XCZXGTMEAKBVPV-UHFFFAOYSA-N trimethylgallium Chemical compound C[Ga](C)C XCZXGTMEAKBVPV-UHFFFAOYSA-N 0.000 claims description 5
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 4
- 229910052737 gold Inorganic materials 0.000 claims description 4
- 229910052738 indium Inorganic materials 0.000 claims description 4
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 claims description 4
- 238000001259 photo etching Methods 0.000 claims description 4
- 238000001816 cooling Methods 0.000 claims description 3
- AXAZMDOAUQTMOW-UHFFFAOYSA-N dimethylzinc Chemical compound C[Zn]C AXAZMDOAUQTMOW-UHFFFAOYSA-N 0.000 claims description 3
- 229920002120 photoresistant polymer Polymers 0.000 claims description 3
- 238000003825 pressing Methods 0.000 claims description 3
- 230000009467 reduction Effects 0.000 claims description 3
- RGGPNXQUMRMPRA-UHFFFAOYSA-N triethylgallium Chemical compound CC[Ga](CC)CC RGGPNXQUMRMPRA-UHFFFAOYSA-N 0.000 claims description 3
- 239000000084 colloidal system Substances 0.000 claims description 2
- 238000000151 deposition Methods 0.000 claims description 2
- AJNVQOSZGJRYEI-UHFFFAOYSA-N digallium;oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[Ga+3].[Ga+3] AJNVQOSZGJRYEI-UHFFFAOYSA-N 0.000 claims description 2
- 229910001195 gallium oxide Inorganic materials 0.000 claims description 2
- 238000004544 sputter deposition Methods 0.000 claims description 2
- 150000001875 compounds Chemical class 0.000 claims 2
- 229910007486 ZnGa2O4 Inorganic materials 0.000 abstract description 16
- 230000031700 light absorption Effects 0.000 abstract description 9
- 239000013078 crystal Substances 0.000 abstract description 8
- 230000004044 response Effects 0.000 abstract description 6
- 230000000052 comparative effect Effects 0.000 description 10
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 8
- 229910052594 sapphire Inorganic materials 0.000 description 5
- 239000010980 sapphire Substances 0.000 description 5
- 238000001228 spectrum Methods 0.000 description 5
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- 238000002441 X-ray diffraction Methods 0.000 description 4
- QZQVBEXLDFYHSR-UHFFFAOYSA-N gallium(III) oxide Inorganic materials O=[Ga]O[Ga]=O QZQVBEXLDFYHSR-UHFFFAOYSA-N 0.000 description 4
- 239000004065 semiconductor Substances 0.000 description 4
- 239000011787 zinc oxide Substances 0.000 description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 3
- 230000003287 optical effect Effects 0.000 description 3
- 229910052710 silicon Inorganic materials 0.000 description 3
- 239000010703 silicon Substances 0.000 description 3
- 229910002704 AlGaN Inorganic materials 0.000 description 2
- XSTXAVWGXDQKEL-UHFFFAOYSA-N Trichloroethylene Chemical group ClC=C(Cl)Cl XSTXAVWGXDQKEL-UHFFFAOYSA-N 0.000 description 2
- 229910003363 ZnMgO Inorganic materials 0.000 description 2
- 238000000862 absorption spectrum Methods 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000005034 decoration Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000005286 illumination Methods 0.000 description 2
- 239000011777 magnesium Substances 0.000 description 2
- 229910052749 magnesium Inorganic materials 0.000 description 2
- -1 magnesium aluminate Chemical class 0.000 description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 2
- 238000002488 metal-organic chemical vapour deposition Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000011056 performance test Methods 0.000 description 2
- 238000001420 photoelectron spectroscopy Methods 0.000 description 2
- UBOXGVDOUJQMTN-UHFFFAOYSA-N trichloroethylene Natural products ClCC(Cl)Cl UBOXGVDOUJQMTN-UHFFFAOYSA-N 0.000 description 2
- 238000001771 vacuum deposition Methods 0.000 description 2
- 238000001039 wet etching Methods 0.000 description 2
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- 230000004071 biological effect Effects 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000001941 electron spectroscopy Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000004298 light response Effects 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002923 metal particle Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000003595 spectral effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 238000000825 ultraviolet detection Methods 0.000 description 1
- 238000002371 ultraviolet--visible spectrum Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/08—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors
- H01L31/10—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors characterised by potential barriers, e.g. phototransistors
- H01L31/101—Devices sensitive to infrared, visible or ultraviolet radiation
- H01L31/102—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier
- H01L31/108—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier being of the Schottky type
- H01L31/1085—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier being of the Schottky type the devices being of the Metal-Semiconductor-Metal [MSM] Schottky barrier type
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- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
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- H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
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- H01L31/0264—Inorganic materials
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Abstract
The invention provides a ZnGaO ultraviolet detector. The crystalline phase of the ZnGaO film used by the ZnGaO ultraviolet detector provided by the invention is ZnGa2O4The structure, the light absorption cut-off edge is positioned near 250nm, and the atomic ratio of zinc and gallium is 1:2, the proportion of gallium atoms is higher, but the material can still maintain ZnGa2O4The crystal structure of (1). The ZnGaO ultraviolet detector provided by the invention and the traditional ZnGa2O4Compared with the ultraviolet detector, the ultraviolet detector has higher peak value responsivity, and parameters of dark current and response time are basically unchanged, so that an effective method is provided for improving performance parameters of the ZnGaO ultraviolet detector.
Description
Technical Field
The invention belongs to the technical field of semiconductor photoelectric detectors, and particularly relates to a ZnGaO ultraviolet detector and a preparation method thereof.
Background
The ultraviolet detector is widely applied to the fields of astronomy, combustion engineering, water purification treatment, flame detection, biological effect, interplanetary communication, environmental pollution monitoring and the like. Due to the absorption of an ozone layer in the atmosphere, ultraviolet light with the wavelength less than 280nm is hardly generated on the earth surface, the spectrum region is called a solar blind waveband, and due to the fact that interference of sunlight does not exist, the solar blind ultraviolet detector working in the waveband has high sensitivity and can be used for missile early warning and the like. Therefore, solar blind ultraviolet detectors are receiving wide attention.
At present, a detector applied in military and actual life mainly takes a silicon-based ultraviolet photoelectric tube and a photomultiplier as main components, but the silicon-based ultraviolet photoelectric tube and the photomultiplier are heavy in size and high in power consumption, and an optical filter is required to be arranged on the detector, so that the application popularization of the silicon-based ultraviolet photoelectric tube and the photomultiplier is limited to a great extent.
The most studied semiconductor materials at present mainly comprise AlGaN alloy of III-V group and ZnMgO alloy of II-VI group. The currently reported GaN can broaden the energy band to the solar blind area by doping aluminum, and is made into detectors with structures such as MSM, p-n and the like. However, the growth temperature of AlGaN is high, and the alloy crystal quality of the high aluminum component is poor. ZnGa2O4Is ZnO and Ga2O3The composite oxide has a spinel structure, belongs to a direct band gap semiconductor, has a forbidden band width of 4.4-5.0eV, and can be applied to the fields of ultraviolet photoelectric devices and the like within the range of 248-280nm in principle. ZnGa2O4Compared with ZnMgO, the structure phase splitting problem can be avoided; ZnGa2O4And Ga2O3Compared with the prior art, the method can realize electrical characteristic regulation and control and improve conductivity. And due to ZnGa2O4The method has the advantages of good stability and radiation resistance, high electron saturation drift velocity and the like. Thus, ZnGa2O4Is a candidate material for preparing solar blind ultraviolet detectors.
However, the conventional ZnGa compound2O4The ultraviolet detector prepared by the thin film material has lower peak value responsivity, and the ultraviolet detection performance is influenced. How to improve the performance of the ZnGaO ultraviolet detector is still one of the key problems faced by the devices.
Disclosure of Invention
In view of this, the technical problem to be solved by the present invention is to provide a ZnGaO ultraviolet detector and a method for manufacturing the same.
The invention provides a ZnGaO ultraviolet detector, which comprises a substrate, a zinc-gallium-oxygen material film, a metal interdigital electrode and an indium electrode which are sequentially compounded;
the atomic ratio of zinc to gallium in the zinc-gallium-oxygen material film is less than 1:2, and the zinc-gallium-oxygen material film is of a spinel structure.
Preferably, the absorption cut-off edge of the zinc-gallium-oxygen material thin film is positioned at 250 +/-10 nm.
Preferably, the preparation method of the zinc-gallium-oxygen material film comprises the following steps:
an organic zinc compound is used as a zinc source, an organic gallium compound is used as a gallium source, high-purity oxygen is used as an oxygen source, and a metal organic compound chemical vapor deposition method is utilized to grow a zinc-gallium-oxygen material film on the surface of a substrate.
Preferably, the organic zinc compound is diethyl zinc and/or dimethyl zinc; the organic gallium compound is trimethyl gallium and/or triethyl gallium.
Preferably, the organic zinc compound takes high-purity nitrogen as carrier gas, the initial flow rate of the carrier gas is 5-20 mL/min, the flow rate of the carrier gas is gradually reduced in the process of growing the zinc-gallium-oxygen material film, and the reduction rate is 0-4.5 mL/30 min; the duration of reducing the flow of the carrier gas is 0-5 hours;
the organic gallium compound takes high-purity nitrogen as carrier gas, the initial flow rate of the carrier gas is 5-40 mL/min, the flow rate of the carrier gas is gradually increased in the process of growing the zinc-gallium-oxygen material film, and the increasing rate is 0-4.5 mL/30 min; the duration of the increase in the flow rate of the carrier gas is 0 to 5 hours.
Preferably, the flow rate of the oxygen is 100-1000 mL/min.
Preferably, the growth time is 0.5-5 h, the growth starting temperature is 500-800 ℃, the growth temperature is gradually increased at a heating rate of 0.01-5 ℃/min in the process of growing the zinc-gallium-oxygen material film, the heating time is 0.5-5 h, and the heating time is less than or equal to the growth time;
the growth was carried out under a vacuum of 2 x 102～1*104Pa。
Preferably, after the growth is finished, the temperature of the substrate is reduced to room temperature, and the cooling rate is 0.1-50 ℃/min.
Preferably, the metal interdigital electrode is a gold interdigital electrode, and the thickness of the metal interdigital electrode is 20-40 nm.
The invention also provides a preparation method of the ultraviolet detector, which comprises the following steps:
A) taking an organic zinc compound as a zinc source, taking an organic gallium compound as a gallium source, taking high-purity oxygen as an oxygen source, and depositing a zinc-gallium-oxygen material film on the surface of a substrate by utilizing a metal organic compound chemical vapor deposition method;
B) forming an interdigital electrode mask on the zinc-gallium-oxygen material film by using negative photoresist photoetching, and removing the colloid mask after metal sputtering to obtain a metal interdigital electrode;
C) and pressing In particles on the interdigital electrode to obtain the ZnGaO ultraviolet detector with the MSM structure.
Compared with the prior art, the invention provides a ZnGaO ultraviolet detector, which comprises a substrate, a zinc-gallium-oxygen material film, a metal interdigital electrode and an indium electrode which are sequentially compounded; the atomic ratio of zinc to gallium in the zinc-gallium-oxygen material film is less than 1:2, and the zinc-gallium-oxygen material film is of a spinel structure. The crystalline phase of the ZnGaO film used by the ZnGaO ultraviolet detector provided by the invention is ZnGa2O4The structure, the light absorption cut-off edge is positioned near 250nm, and the atomic ratio of zinc and gallium is 1:2, the proportion of gallium atoms is higher, but the material can still maintain ZnGa2O4The crystal structure of (1). The ZnGaO ultraviolet detector provided by the invention and the traditional ZnGa2O4Compared with the ultraviolet detector, the ultraviolet detector has higher peak value responsivity, and parameters of dark current and response time are basically unchanged, so that an effective method is provided for improving performance parameters of the ZnGaO ultraviolet detector.
Drawings
FIG. 1 is a schematic structural diagram of a ZnGaO ultraviolet detector;
FIG. 2 is an X-ray diffraction (XRD) spectrum of the ZnGaO film of example 1;
FIG. 3 is an electron spectroscopy (EDS) spectrum of the ZnGaO film of example 1;
FIG. 4 is a UV-VIS absorption spectrum of the ZnGaO film of example 1;
fig. 5 is a graph of the optical response of the ZnGaO ultraviolet detectors in example 1 and comparative example 1;
fig. 6 is an IV curve of the ZnGaO ultraviolet detectors in example 1 and comparative example 1;
fig. 7 is a graph of the optical switching curves of the ZnGaO ultraviolet detectors in example 1 and comparative example 1.
Detailed Description
The invention provides a ZnGaO ultraviolet detector, which comprises a substrate, a zinc-gallium-oxygen material film, a metal interdigital electrode and an indium electrode which are sequentially compounded;
the atomic ratio of zinc to gallium in the zinc-gallium-oxygen material film is less than 1:2, and the zinc-gallium-oxygen material film is of a spinel structure.
Referring to fig. 1, fig. 1 is a schematic structural diagram of a ZnGaO ultraviolet detector.
The ultraviolet detector provided by the present invention includes a substrate, which is well known to those skilled in the art, and is not particularly limited, and a sapphire substrate, magnesium oxide or magnesium aluminate is preferred in the present invention.
The ultraviolet detector also comprises a zinc-gallium-oxygen material film compounded on the substrate.
The atomic ratio of zinc to gallium in the zinc-gallium-oxygen material film is less than 1:2, and the zinc-gallium-oxygen material film is of a spinel structure.
In the invention, the chemical formula of the zinc-gallium-oxygen material film is ZnxGayO4And x: y < 1:2, preferably, 1: 4.1. ltoreq. x: y is less than 1: 2.
In some embodiments of the invention, the atomic ratio of zinc to gallium is 1:4. 1: 2.1,1: 2.5, 1: 3 or 1: 4.1.
the crystalline phase of the zinc-gallium-oxygen film is ZnGa2O4The structure has the light absorption cut-off edge positioned at 250 +/-10 nm and the absorption edge is very steep.
The film with large area can be prepared, and the light absorption property and the crystal structure of the film are very uniform in all ranges, wherein the area of the film is (0.1-6) cm multiplied by (0.1-6).
The preparation method of the zinc-gallium-oxygen material film comprises the following steps:
an organic zinc compound is used as a zinc source, an organic gallium compound is used as a gallium source, high-purity oxygen is used as an oxygen source, and a metal organic compound chemical vapor deposition method is utilized to grow a zinc-gallium-oxygen material film on the surface of a substrate.
In the invention, the atomic ratio of zinc to gallium in the zinc-gallium-oxygen material film can be made to be less than 1:2 through three ways.
(1) Gradually increasing the carrier gas flow of the gallium source in the growth process;
(2) gradually reducing the carrier gas flow of the zinc source in the growth process;
(3) the growth temperature was gradually increased.
In the above three modes, one mode may be adopted alone, or any two or more of the three modes may be combined.
Specifically, before carrying out the metal organic compound chemical vapor deposition, the substrate is cleaned, and the method comprises the following steps:
the substrate was washed sequentially with trichloroethylene, acetone and ethanol and then blown dry with dry nitrogen.
The substrate is sapphire, magnesium oxide, zinc oxide or magnesium aluminate, and is preferably sapphire.
Then, placing the substrate into MOCVD growth equipment, and adjusting the initial growth temperature to be 500-800 ℃, wherein the vacuum degree of a growth chamber in the growth equipment is 2 x 102～1*104Pa, preferably 8X 102～5×103Pa。
The organic zinc compound is diethyl zinc and/or dimethyl zinc; the organic gallium compound is trimethyl gallium and/or triethyl gallium.
The molar concentration ratio of zinc and gallium was adjusted using different ratios of high purity nitrogen carrier gas.
The organic zinc compound takes high-purity nitrogen as carrier gas, the initial flow rate of the carrier gas is 5-20 mL/min, preferably 10-15 mL/min, the flow of the carrier gas is gradually reduced in the process of growing the zinc-gallium-oxygen material film, and the reduction rate is 0-4.5 mL/30min, preferably 0.5-4 mL/30min, and further preferably 1-3 mL/30 min; the duration time for reducing the flow rate of the carrier gas is 0-5 hours, preferably 1-5 hours, and further preferably 2-4 hours;
the organic gallium compound takes high-purity nitrogen as carrier gas, the initial flow rate of the carrier gas is 5-40 mL/min, preferably 10-35 mL/min, and further preferably 15-30 mL/min, the flow of the carrier gas is gradually increased in the process of growing the zinc-gallium-oxygen material film, and the increasing rate is 0-4.5 mL/30min, preferably 0.5-4 mL/30min, and further preferably 1-3 mL/30 min; the duration of the increase in the flow rate of the carrier gas is 0 to 5 hours, preferably 1 to 5 hours, and more preferably 2 to 4 hours.
The flow rate of the oxygen is 100-1000 mL/min.
When the thin film is grown, the growth time is 0.5-5 h, preferably 1-4 h, and the initial growth temperature is 500-800 ℃, preferably 600-700 ℃.
In the process of growing the zinc-gallium-oxygen material film, gradually raising the growth temperature at a temperature raising rate of 0.01-5 ℃/min, preferably at a temperature raising rate of 0.05-5 ℃/min, and further preferably at a temperature raising rate of 0.1-3 ℃/min; the temperature rise time is 0.5-5 h, and the temperature rise time is not more than the growth time. In the present invention, the temperature raising process may be performed intermittently or continuously. Wherein the maximum temperature of the temperature rise is 950 ℃.
And after the growth is finished, reducing the temperature of the substrate to room temperature, wherein the cooling rate is 0.1-50 ℃/min. In the present invention, the room temperature is defined as 25. + -. 5 ℃.
The thickness of the zinc-gallium-oxygen material film is 100-600 nm, preferably 200-500 nm, and more preferably 300-400 nm.
Then, the substrate attached with the zinc-gallium-oxygen material film is placed in a vacuum coating machine, an interdigital electrode mask is formed by using negative photoresist lithography,
specifically, the pressure is 1 × 10-3～1×10-2And under the condition of Pa, evaporating 5-500 mg of metal particles to the surface of the zinc-gallium-oxygen material film by using an evaporation current of 10-140A, and then photoetching and wet etching the metal on the surface to obtain the metal interdigital electrode. In the present invention, the metal interdigital electrode is preferably a gold interdigital electrode.
In the invention, the inter-finger distance of the metal interdigital electrode is 2-10 mu m, the number of pairs of the interdigital is 10-25, the length of the interdigital is 0.5-2 mm, and the width of the interdigital is 2-10 mu m.
And finally, pressing In particles on the metal interdigital electrode to obtain the ZnGaO ultraviolet detector with the MSM structure.
The invention relates to a performance characterization method of a zinc-gallium-oxygen ultraviolet detector, which comprises the following steps: the crystal structure was characterized using X-ray diffraction (XRD). Photoelectron spectroscopy (EDS) was used to characterize the elemental proportions of the material. And testing the light absorption condition of the material by using an ultraviolet-visible light absorption spectrum instrument, and measuring the spectral response curve of the device by using a light response measuring system. The IV curve (acquiring dark current data) and the photoswitch curve (acquiring response time data) of the device were measured using a semiconductor analyzer.
For further understanding of the present invention, the ZnGaO ultraviolet detector and the preparation method thereof provided by the present invention are described below with reference to the following examples, and the scope of the present invention is not limited by the following examples.
Example 1:
the preparation process of the ZnGaO ultraviolet detector is as follows:
(1) the sapphire substrate was cleaned with trichloroethylene, acetone, and ethanol, respectively, and then blown dry with dry nitrogen.
(2) Placing the sapphire substrate in the step (1) into MOCVD growth equipment, wherein the initial growth temperature is 700 ℃, and the vacuum degree of a growth chamber is 1 x 103Pa, using diethyl zinc as zinc source, trimethyl gallium as gallium source, adjusting molar concentration ratio of zinc and gallium by using different high-purity nitrogen carrier gas ratios, introducing oxygen at flow rate of 200mL/min, and introducing diethyl zinc tubeThe carrier gas flow rate of the circuit is 10mL/min, and the carrier gas flow rate of the trimethyl gallium pipeline is 30 mL/min.
From the beginning of the growth process, the carrier gas flow rate of the gallium source is gradually increased. The rate of rise was 2mL/30 min. The carrier gas flow was increased for a duration of 1 hour.
From the beginning of the growth process, the growth temperature was gradually increased. The rate of rise was 2 ℃/min for 1.5 hours.
(3) And (4) growing for 2 hours, turning off the organic source, reducing the temperature at the speed of 5 ℃/min, finally reducing the temperature to the room temperature, and taking out the substrate.
(4) Putting the sample obtained in the step (3) into a vacuum coating machine, and keeping the air pressure at 1 x 10-3Under Pa, 50mg of Au particles were evaporated onto the sample surface using an evaporation current of 140A.
(5) And (3) photoetching and wet etching the sample obtained In the step (4) for gold on the surface to obtain an interdigital electrode, wherein the interdigital electrode has the finger width of 2 microns, the finger length of 2mm, the number of pairs of 25 and the finger distance of 2 microns, and In particles are pressed on the interdigital electrode to obtain the zinc-gallium-oxygen ultraviolet detector with the MSM structure
Fig. 1 is a schematic structural diagram of a zinc-gallium-oxygen ultraviolet detector. FIG. 2 is an X-ray diffraction (XRD) spectrum of a zinc-gallium-oxygen thin film, from which it can be seen that the obtained material is ZnGa2O4A crystalline phase structure. The absorption peak of XRD is sharp, which indicates that the crystal quality is high. Fig. 3 is a spectrum of photoelectron spectroscopy (EDS) of the zinc gallium oxide thin film of example 1, and it can be seen that the ratio of zinc element to gallium element is about 1:4. with standard ZnGa2O4Ratio of zinc and gallium of the film 1:2, the proportion of gallium atoms is higher. FIG. 4 is a graph of UV-visible absorption spectrum of a ZnGa oxide film, from which it can be seen that the film has a steep single light absorption cut-off edge, which is around 250 nm.
Comparative example 1:
comparative example 1 compared with example 1, the process of gradually increasing the carrier gas flow rate of the gallium source during the growth was eliminated, while the process of gradually increasing the growth temperature during the growth, that is, maintaining the carrier gas flow rate of the gallium source and maintaining the growth temperature at the starting temperature, was eliminated. Other conditions were unchanged. And obtaining a corresponding device. The atomic ratio of zinc to gallium in the device is 1: 2.
the devices obtained in comparative example 1 and comparative example 1 were compared. From the results, it is known that as the amount of gallium in the atomic ratio of zinc and gallium increases, the responsivity of the device is significantly improved (see fig. 5), while the dark current (see fig. 6) and the response time (see fig. 7) are substantially unchanged.
As shown in FIG. 5, the peak responsivity of the device of example 1 was 40A/W, and the peak responsivity of the device of comparative example 1 was 10A/W
As shown in FIG. 6, the dark current at a voltage of 10V was 1.9nA for the device of example 1, and 1.8nA for the device of comparative example 1
As shown in fig. 7, the time required for the current to drop to one-thousandth of the original state after the illumination was turned off in the device of example 1 was about 500 milliseconds, and the time required for the current to drop to one-thousandth of the original state after the illumination was turned off in the device of comparative example 1 was also about 500 milliseconds.
Example 2
Compared with example 1, a batch of samples was prepared by changing only the rate of increase of the carrier gas flow rate of the gallium source without changing other conditions. The rising rate of the gallium source carrier gas flow of the sample numbers of 2-1, 2-2, 2-3, 2-4, 2-5 is 0.1mL/30 min; 0.5mL/30 min; 1mL/30 min; 3mL/30 min; 5mL/30 min.
The results are respectively:
2-1, 2-2, 2-3, 2-4 the resulting material was ZnGa2O4The crystal phase structure has a light absorption cut-off edge of about 250 nm.
2-5 samples the resulting material exhibited a small amount of Ga2O3And a crystalline structure of ZnO, with two absorption cut-off edges.
2-1, 2-2, 2-3, 2-4, 2-5 samples had ratios of zinc element to gallium element of approximately 1/2.1,1/2.5,1/3,1/4.1,1/4.5
The peak responsivity of the device prepared in example 2, the dark current at a voltage of 10V and the time required for the current to drop to one thousandth of the original state after the device was turned off from light were measured and the results are shown in table 1.
Table 1 performance test results of the devices
Example 3
Compared to example 1, a batch of samples was prepared with only the rate of temperature increase during the generation being changed, and without changing other conditions. The heating rates of the sample numbers 3-1, 3-2, 3-3, 3-4 and 3-5 are respectively 0.1 ℃/min,1 ℃/min,5 ℃/min,6 ℃/min and 8 ℃/min (the heating time is 90min if the temperature does not reach 950 ℃, and the temperature is not increased if the temperature is increased to 950 ℃)
The results are respectively:
the obtained material of the sample of 3-1, 3-2, 3-3 was ZnGa2O4The crystal phase structure has a light absorption cut-off edge of about 250 nm.
Samples of 3-4, 3-5 gave materials which exhibited small amounts of Ga2O3And a crystalline structure of ZnO, with two absorption cut-off edges.
The ratio of zinc element to gallium element in samples 3-1, 3-2, 3-3, 3-4, 3-5 was about 1/2.1,1/3,1/4.1,1/4.2, 1/4.4.
The peak responsivity of the device prepared in example 3, the dark current at a voltage of 10V and the time required for the current to drop to one thousandth of the original state after the device was turned off were measured and the results are shown in table 2.
TABLE 2 Performance test results of the devices
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (10)
1. A ZnGaO ultraviolet detector is characterized by comprising a substrate, a zinc-gallium-oxygen material film, a metal interdigital electrode and an indium electrode which are sequentially compounded;
the atomic ratio of zinc to gallium in the zinc-gallium-oxygen material film is less than 1:2, and the zinc-gallium-oxygen material film is of a spinel structure.
2. The ultraviolet detector of claim 1, wherein the absorption cut-off edge of the zinc gallium oxide material thin film is located at 250 ± 10 nm.
3. The ultraviolet detector according to claim 1, wherein the preparation method of the zinc-gallium-oxygen material film comprises the following steps:
an organic zinc compound is used as a zinc source, an organic gallium compound is used as a gallium source, high-purity oxygen is used as an oxygen source, and a metal organic compound chemical vapor deposition method is utilized to grow a zinc-gallium-oxygen material film on the surface of a substrate.
4. The UV detector according to claim 3, characterized in that the organozinc compound is diethylzinc and/or dimethylzinc; the organic gallium compound is trimethyl gallium and/or triethyl gallium.
5. The ultraviolet detector according to claim 3, wherein the organozinc compound uses high-purity nitrogen as a carrier gas, the initial flow rate of the carrier gas is 5-20 mL/min, and the flow rate of the carrier gas is gradually reduced in the process of growing the zinc-gallium-oxygen material film, and the reduction rate is 0-4.5 mL/30 min; the duration of reducing the flow of the carrier gas is 0-5 hours;
the organic gallium compound takes high-purity nitrogen as carrier gas, the initial flow rate of the carrier gas is 5-40 mL/min, the flow rate of the carrier gas is gradually increased in the process of growing the zinc-gallium-oxygen material film, and the increasing rate is 0-4.5 mL/30 min; the duration of the increase in the flow rate of the carrier gas is 0 to 5 hours.
6. The UV detector according to claim 3, wherein the flow rate of the oxygen is 100-1000 mL/min.
7. The ultraviolet detector according to claim 3, wherein the growth time is 0.5-5 h, the growth starting temperature is 500-800 ℃, the growth temperature is gradually increased at a heating rate of 0.01-5 ℃/min during the growth of the zinc-gallium-oxygen material thin film, the heating time is 0.5-5 h, and the heating time is less than or equal to the growth time;
the growth was carried out under a vacuum of 2 x 102～1*104Pa。
8. The ultraviolet detector according to claim 3, wherein after the growth is finished, the temperature of the substrate is reduced to room temperature, and the cooling rate is 0.1-50 ℃/min.
9. The ultraviolet detector according to claim 1, wherein the metal interdigital electrode is a gold interdigital electrode, and the thickness of the metal interdigital electrode is 20-40 nm.
10. A method for preparing an ultraviolet detector according to any one of claims 1 to 9, comprising the steps of:
A) taking an organic zinc compound as a zinc source, taking an organic gallium compound as a gallium source, taking high-purity oxygen as an oxygen source, and depositing a zinc-gallium-oxygen material film on the surface of a substrate by utilizing a metal organic compound chemical vapor deposition method;
B) forming an interdigital electrode mask on the zinc-gallium-oxygen material film by using negative photoresist photoetching, and removing the colloid mask after metal sputtering to obtain a metal interdigital electrode;
C) and pressing In particles on the interdigital electrode to obtain the ZnGaO ultraviolet detector with the MSM structure.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111584658A (en) * | 2020-06-28 | 2020-08-25 | 中国科学院长春光学精密机械与物理研究所 | Ga2O3Ultraviolet detector and preparation method thereof |
| CN111710592A (en) * | 2020-06-28 | 2020-09-25 | 中国科学院长春光学精密机械与物理研究所 | Ga2O3Film and preparation method thereof |
| CN111785795A (en) * | 2020-08-11 | 2020-10-16 | 中国科学院长春光学精密机械与物理研究所 | ZnMgGaO ultraviolet detector and preparation method thereof |
| CN114657637A (en) * | 2022-03-10 | 2022-06-24 | 中国科学院长春光学精密机械与物理研究所 | Zinc gallate thin film and preparation method thereof, ultraviolet detector and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106409963A (en) * | 2016-09-21 | 2017-02-15 | 浙江理工大学 | Zn: Ga2O3 film-based MSM structure solar-blind ultraviolet photoelectric detector and preparation method thereof |
| CN108922930A (en) * | 2018-07-12 | 2018-11-30 | 中国科学院长春光学精密机械与物理研究所 | A kind of ZnMgO ultraviolet detector |
| CN108962732A (en) * | 2018-07-12 | 2018-12-07 | 中国科学院长春光学精密机械与物理研究所 | A kind of ZnMgO film and preparation method thereof |
| TW201913979A (en) * | 2017-09-12 | 2019-04-01 | 鼎元光電科技股份有限公司 | Solar-Blind Detecting Device With Wide Bandgap Oxide |
| CN110416334A (en) * | 2018-08-31 | 2019-11-05 | 西安电子科技大学 | One kind being based on hetero-epitaxy Ga2O3The preparation method of film deep ultraviolet light electric explorer |
-
2019
- 2019-12-11 CN CN201911266460.8A patent/CN111029435A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106409963A (en) * | 2016-09-21 | 2017-02-15 | 浙江理工大学 | Zn: Ga2O3 film-based MSM structure solar-blind ultraviolet photoelectric detector and preparation method thereof |
| TW201913979A (en) * | 2017-09-12 | 2019-04-01 | 鼎元光電科技股份有限公司 | Solar-Blind Detecting Device With Wide Bandgap Oxide |
| CN108922930A (en) * | 2018-07-12 | 2018-11-30 | 中国科学院长春光学精密机械与物理研究所 | A kind of ZnMgO ultraviolet detector |
| CN108962732A (en) * | 2018-07-12 | 2018-12-07 | 中国科学院长春光学精密机械与物理研究所 | A kind of ZnMgO film and preparation method thereof |
| CN110416334A (en) * | 2018-08-31 | 2019-11-05 | 西安电子科技大学 | One kind being based on hetero-epitaxy Ga2O3The preparation method of film deep ultraviolet light electric explorer |
Non-Patent Citations (1)
| Title |
|---|
| RAY-HUA HORNG ET AL: ""Epitaxial growth of ZnGa2O4:A new, deep ultraviolet semiconductor candidate"", 《CRYSTAL GROWTH & DESIGN》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111584658A (en) * | 2020-06-28 | 2020-08-25 | 中国科学院长春光学精密机械与物理研究所 | Ga2O3Ultraviolet detector and preparation method thereof |
| CN111710592A (en) * | 2020-06-28 | 2020-09-25 | 中国科学院长春光学精密机械与物理研究所 | Ga2O3Film and preparation method thereof |
| CN111584658B (en) * | 2020-06-28 | 2022-07-08 | 中国科学院长春光学精密机械与物理研究所 | Ga2O3Ultraviolet detector and preparation method thereof |
| CN111785795A (en) * | 2020-08-11 | 2020-10-16 | 中国科学院长春光学精密机械与物理研究所 | ZnMgGaO ultraviolet detector and preparation method thereof |
| CN111785795B (en) * | 2020-08-11 | 2024-04-19 | 中国科学院长春光学精密机械与物理研究所 | ZnMgGaO ultraviolet detector and preparation method thereof |
| CN114657637A (en) * | 2022-03-10 | 2022-06-24 | 中国科学院长春光学精密机械与物理研究所 | Zinc gallate thin film and preparation method thereof, ultraviolet detector and preparation method thereof |
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