A self-powered deep ultraviolet photodetector based on quartz / beta-ga2o3 / cupc and a preparation method thereof

Abstract

The application relates to a deep ultraviolet photodetector system, in particular to a self-powered deep ultraviolet photodetector based on quartz / beta-Ga2O3 / CuPc and a preparation method thereof. A CuPc film is first deposited on a gallium oxide film grown by MOCVD through a spin coating method, wherein an Au / Ti electrode is plated on the gallium oxide film by magnetron sputtering, and an Au electrode is plated on the CuPc film, so as to prepare a self-powered deep ultraviolet photodetector based on quartz / beta-Ga2O3 / CuPc. The deep ultraviolet photodetector prepared by the application has the advantages that the deep ultraviolet photodetector has stable performance, has a solar blind characteristic for the spectrum of an electric network corona deep ultraviolet wave band (220nm-280nm), is resistant to high temperature, and even under high temperature or long-term DUV irradiation, the equipment can maintain high photoelectric current.

Description

TECHNICAL FIELD

[0001] The application relates to a deep ultraviolet photodetector, in particular to a self-powered deep ultraviolet photodetector based on quartz / beta-Ga2O3 / CuPc. BACKGROUND

[0002] Deep ultraviolet (DUV, 200-280 nm) photodetectors, as an important component of spectral detectors, have a variety of important uses, including missile tracking, navigation, communication and monitoring. Although the traditional silicon-based DUV photodetector is low in price and mature in technology, it has limited response capability to DUV light, weak penetration depth to high-energy ultraviolet photons and low dependence on the filtering of these photons. Recently, wide-bandgap semiconductors such as MgZnO, AlGaN, diamond and Ga2O3 are considered to be disruptive alternatives to silicon in advanced DUV photodetectors. Gallium oxide is the most ideal choice in the application of DUV photodetectors due to its ultra-wide bandgap semiconductor (4.5-4.9 eV), strong ultraviolet photon absorption coefficient, high structural stability and bearability. The structure of the beta-Ga2O3-based DUV photodetector is crucial to its performance.

[0003] Initially, the device structure is mainly photoconductive and metal-semiconductor-metal structure (MSM), which has the advantages of simple production and easy integration in device preparation, but also has the disadvantages of slow response speed, small photosensitive area and external bias. The self-powered photodetector based on photovoltaic effect can detect optical signals without bias, eliminates power distribution devices, meets the development needs of energy saving, and has attracted widespread attention. The self-powered photodetector based on Ga2O3 has all-inorganic heterojunction, organic-inorganic hybrid heterojunction, phase junction and Schottky junction. Although the inorganic heterojunction photodetector has a high response rate, the inorganic semiconductor with high carrier concentration has a narrow bandgap and a risk of responding to light in the non-DUV region, and some organic molecular materials with strong hole mobility and natural DUV shunt characteristics are suitable for constructing organic-inorganic hybrid self-powered photodetectors with gallium oxide.

[0004] Copper phthalocyanine is just such an organic molecular material. Unlike other organic compounds, phthalocyanine can sublimate, the thin film can remain stable at high temperature without degradation, CuPc powder has the advantages of simple production path, high purity, good solubility and weak absorption in the UVC region, and due to its clear molecular structure, it can meet the requirements of solar blind photodetectors. At the same time, the high-speed transmission of CuPc photo-generated holes and the large built-in field obtained by the beta-Ga2O3 / CuPc pn junction provide excellent photoelectric performance. SUMMARY

[0005] The application aims to provide a self-powered deep ultraviolet photodetector with high sensitivity and stability, which can maintain high photocurrent even under high temperature or long-term DUV irradiation.

[0006] The technical scheme of the application is:

[0007] A self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc includes a β-Ga2O3 film, a quartz substrate, a CuPc film, an Au / Ti electrode and an Au electrode.

[0008] Further, the β-Ga2O3 film is located above the quartz substrate, the CuPc film is located above the Ga2O3 film, the Au / Ti electrode is located above the β-Ga2O3 film, and the Au electrode is located above the CuPc film.

[0009] Further, the thickness of the β-Ga2O3 film is 1110nm-1125nm, the thickness of the CuPc film is 190nm-210nm, the surface area of the CuPc film is 50% of the surface area of the β-Ga2O3 film, and the length and width of the Au / Ti electrode and the Au electrode are 0.7cm-0.9cm*0.1cm-0.4cm.

[0010] A preparation method of a self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc includes the following steps:

[0011] (1) Preparation of a β-Ga2O3 / CuPc film:

[0012] Gallium oxide film is grown on quartz at 850-860℃ for 60-90min by metal-organic chemical vapor deposition (MOCVD), and the prepared film is shielded by half with hot melt adhesive for standby, then 0.5-2g of CuPc solid powder is weighed with an electronic balance, added into 0.5-1L of ethanol solution, and stirred for 1-1.5h with a magnetic stirrer to disperse the CuPc powder in the ethanol solution, obtaining a CuPc dispersion of 1-2mg / ml.

[0013] The CuPc dispersion is spin-coated on the prepared film by using a spin coater at a mode of 3000-4000r / s for 40-60s each time, and then heated at 90-100℃ for 10-20min on a heating table to remove the hot melt adhesive.

[0014] (2) Preparation of a deep ultraviolet detector based on a quartz / β-Ga2O3 / CuPc photoelectrochemical chip:

[0015] The deep ultraviolet detector device is built by magnetron sputtering. The electrode is prepared by magnetron sputtering: Au / Ti electrode is prepared on the prepared beta-Ga2O3 / CuPc film, the length and width of the Au / Ti electrode is 0.7cm-0.9cm*0.1cm-0.4cm. Au electrode is prepared on the CuPc film, the length and width of the Au electrode is 0.7cm-0.9cm*0.1cm-0.4cm. Compared with the point electrode, the strip electrode can be more conducive to carrier transport, the distance between the Au / Ti electrode and the Au electrode should be strictly controlled in 0.1cm-0.2cm, and they are on the same horizontal line. The self-powered deep ultraviolet photodetector based on quartz / beta-Ga2O3 / CuPc is used to test the photoelectric performance by Keithley 2400 and 6487.

[0016] The prepared detector based on the preparation method of the self-powered deep ultraviolet photodetector based on quartz / beta-Ga2O3 / CuPc is applied in deep ultraviolet detection.

[0017] Further, the detector corresponds to the deep ultraviolet spectrum of 220nm-280nm wave band, and works with zero power consumption.

[0018] Advantages of the present application

[0019] 1. The self-powered deep ultraviolet photodetector of quartz / beta-Ga2O3 / CuPc prepared by the method has the characteristics of strong process controllability, simple operation, and recoverability of repeated tests, and has great application prospect.

[0020] 2. The self-powered deep ultraviolet photodetector of quartz / beta-Ga2O3 / CuPc prepared by the method has stable performance, sensitive response, small dark current, day-blind characteristics, zero power consumption, high photocurrent in high temperature environment, and can monitor the deep ultraviolet spectrum of 220nm-280nm wave band. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, the drawings in the following description are only embodiments of the present application, and those skilled in the art can obtain other drawings according to the provided drawings without creative labor.

[0022] Figure 1 is a schematic diagram of the self-powered deep ultraviolet photodetector of quartz / beta-Ga2O3 / CuPc prepared by the method.

[0023] Figure 2is a cross-sectional SEM image of a quartz / β-Ga2O3 / CuPc thin film designed by the method of the application.

[0024] Figure 3 is an I-t curve graph of a quartz / β-Ga2O3 / CuPc-based self-powered deep ultraviolet photodetector made by the method of the application under 254nm ultraviolet light irradiation by continuously turning on and off the light source.

[0025] Figure 4 is an I-t curve graph of a quartz / β-Ga2O3 / CuPc-based self-powered deep ultraviolet photodetector made by the method of the application under 254nm ultraviolet light irradiation by continuously turning on and off the light source.

[0026] Figure 5 is an I-t curve graph of a quartz / β-Ga2O3 / CuPc-based self-powered deep ultraviolet photodetector made by the method of the application under 254nm ultraviolet light irradiation by continuously turning on and off the light source.

[0027] Figure 6 is an I-t curve graph of a quartz / β-Ga2O3 / CuPc-based self-powered deep ultraviolet photodetector made by the method of the application under 254nm ultraviolet light irradiation by continuously turning on and off the light source. DETAILED DESCRIPTION

[0028] The application will be described in detail below with specific embodiments. The following examples will help those skilled in the art to further understand the application, but in no way limit the application. It should be noted that for those skilled in the art, without departing from the concept of the application, a number of modifications and improvements can be made. These are within the scope of the application.

[0029] A quartz / β-Ga2O3 / CuPc-based self-powered deep ultraviolet photodetector includes a β-Ga2O3 thin film, a quartz substrate, a CuPc thin film, an Au / Ti electrode, and an Au electrode.

[0030] The β-Ga2O3 thin film is located above the quartz substrate, the CuPc thin film is located above the Ga2O3 thin film, the Au / Ti electrode is located above the β-Ga2O3 thin film, and the Au electrode is located above the CuPc thin film.

[0031] The thickness of the beta-Ga2O3 thin film is 1110 nm, 1111 nm, 1112 nm, 1113 nm, 1114 nm, 1115 nm, 1116 nm, 1117 nm, 1118 nm, 1119 nm, 1120 nm, 1121 nm, 1122 nm, 1123 nm, 1124 nm, 1125 nm.

[0032] The thickness of the CuPc thin film is 190 nm, 191 nm, 192 nm, 193 nm, 194 nm, 195 nm, 196 nm, 197 nm, 198 nm, 199 nm, 200 nm, 201 nm, 202 nm, 203 nm, 204 nm, 205 nm, 206 nm, 207 nm, 208 nm, 209 nm, 210 nm.

[0033] The surface area of the CuPc thin film is 50% of the surface area of the beta-Ga2O3 thin film.

[0034] The length and width of the Au / Ti electrode and the Au electrode are 0.9 cm*0.1 cm, 0.9 cm*0.2 cm, 0.9 cm*0.3 cm, 0.9 cm*0.4 cm, 0.8 cm*0.1 cm, 0.8 cm*0.2 cm, 0.8 cm*0.3 cm, 0.8 cm*0.4 cm, 0.7 cm*0.1 cm, 0.7 cm*0.2 cm, 0.7 cm*0.3 cm, 0.7 cm*0.4 cm.

[0035] A preparation method of a self-powered deep ultraviolet photodetector based on quartz / beta-Ga2O3 / CuPc, characterized by having the following steps:

[0036] (1) Preparation of beta-Ga2O3 / CuPc thin film:

[0037] Gallium oxide thin film is prepared by growing gallium oxide thin film on quartz at 850 DEG C to 860 DEG C for 60 min to 90 min by metal-organic chemical vapor deposition (MOCVD), and the prepared thin film is shielded by half by using hot melt adhesive for standby, then 0.5 g to 2 g of CuPc solid powder is weighed by an electronic balance, 0.5 L to 1 L of ethanol solution is added, and the CuPc powder is fully dispersed in the ethanol solution by using a magnetic stirrer for 1 h to 1.5 h to obtain a CuPc dispersion of 1 mg / ml to 2 mg / ml;

[0038] The CuPc dispersion liquid is spin-coated on the prepared film by using a spin coating instrument, mode 3000r / s-4000r / s, each time spin coating 40s-60s, and then heated at 90 DEG C-100 DEG C for 10-20 min on a heating table to remove the hot melt adhesive.

[0039] (2) A quartz / β-Ga2O3 / CuPc photoelectrochemical chip-based deep ultraviolet detector is prepared:

[0040] The deep ultraviolet detector is built by magnetron sputtering. The electrode is prepared by magnetron sputtering: Au / Ti electrodes with a length of 0.9 cm, a width of 0.1 cm, 0.2 cm, 0.3 cm, 0.4 cm, 0.8 cm, 0.2 cm, 0.3 cm, 0.4 cm, 0.7 cm, 0.2 cm, 0.3 cm and 0.4 cm are prepared on the prepared β-Ga2O3 / CuPc film. Au electrodes with a length of 0.9 cm, a width of 0.1 cm, 0.2 cm, 0.3 cm, 0.4 cm, 0.8 cm, 0.2 cm, 0.3 cm, 0.4 cm, 0.7 cm, 0.2 cm, 0.3 cm and 0.4 cm are prepared on the CuPc film. Compared with the point electrode, the strip electrode is more conducive to carrier transmission. The positions of the two electrodes are strictly controlled to be 0.1 cm-0.2 cm apart and on the same horizontal line. The self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc is used to test the photoelectric performance by using Keithley 2400 and 6487.

[0041] A self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc corresponds to the deep ultraviolet spectrum of 220nm-280nm wave band and works with zero power consumption.

[0042] The self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc prepared by the method has stable performance, sensitive response, small dark current, day-blind characteristics, zero power consumption, high photocurrent in high temperature environment, and can monitor the deep ultraviolet spectrum of 220nm-280nm wave band.

[0043] Example 1

[0044] The manufacturing method of the self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc has the following steps:

[0045] (1) Preparation of β-Ga2O3 / CuPc film:

[0046] Gallium oxide film was prepared on quartz by metal-organic chemical vapor deposition (MOCVD) at 860°C for 90 min. The prepared film was shielded by half with hot melt adhesive for standby. Then 2 g of CuPc solid powder was weighed and added into 1 L of ethanol solution. The CuPc powder was fully dispersed in the ethanol solution by using a magnetic stirrer for one hour to obtain a CuPc dispersion of 2 mg / ml.

[0047] The CuPc dispersion was spin-coated on the prepared film by using a spin coating instrument at a mode of 3000 r / s for 40 s each time. Then the hot melt adhesive was removed by heating at 100°C for 10-20 minutes on a heating table.

[0048] (2) Manufacturing of a deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc film:

[0049] A deep ultraviolet detector device was built by magnetron sputtering. The electrodes were prepared by magnetron sputtering: Au / Ti electrodes with a length of 0.9 cm and a width of 0.2 cm were sputtered on the β-Ga2O3 film of the prepared β-Ga2O3 / CuPc photoelectrochemical chip, and Au electrodes with a length of 0.9 cm and a width of 0.2 cm were sputtered on the CuPc film. Compared with point electrodes, strip electrodes are more conducive to carrier transport. The positions of the two electrodes were strictly controlled to be 0.2 cm apart and on the same horizontal line. The self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc was tested for photoelectric performance by using Keithley 2400 and 6487.

[0050] The self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc obtained in step (1) was tested for photoelectric performance, as shown in Figure 3 The I-t curve of the self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc under 254 nm ultraviolet light for a long time by continuously turning on and off the light source is shown in the figure. Under negative external bias, the overall system photoelectric current shows negative current, while under positive bias, the overall system photoelectric current shows positive photoelectric current, which can clearly distinguish the direction of the external bias.

[0051] Example 2

[0052] Step (2) is the same as example 1. In step (1), the concentration of CuPc dispersion liquid is 1 mg / ml, 3 mg / ml, 4 mg / ml, 5 mg / ml, using spin coating instrument, mode is 3000 r / s, each spin coating 40 s, CuPc dispersion liquid is spin coated on the prepared film, then heated at 100℃ for 10-20 minutes on the heating table to remove hot melt adhesive.

[0053] The obtained self-powered deep ultraviolet photodetector of quartz / β-Ga2O3 / CuPc is tested for I-V, I-t curves by Keithley 2400 and 6487. As shown in Figure 5 It can be seen that the photocurrent size is reduced compared with example 1, and the remaining performance is similar to example 1.

[0054] Example 3

[0055] Step (2) is the same as example 1. In step (1), the concentration of CuPc dispersion liquid is 2 mg / ml, using spin coating instrument, mode is 3000 r / s, each spin coating 40 s, CuPc dispersion liquid is spin coated on the prepared film twice, then heated at 100℃ for 10-20 minutes on the heating table to remove hot melt adhesive.

[0056] The obtained CuPc film thickness is 395 nm, and the prepared self-powered deep ultraviolet photodetector of quartz / β-Ga2O3 / CuPc is tested for I-V, I-t curves by Keithley 2400 and 6487. It can be seen that the photocurrent size is reduced compared with example 1, and the remaining performance is similar to example 1.

[0057] Example 4

[0058] Step (2) is the same as example 1. In step (2), at the same time, in order to explore the stability of the photodetector in harsh environment, the photoelectric performance is tested by Keithley 2400 and 6487 at room temperature, 50℃, 100℃, 150℃, and the I-t curve at room temperature is compared as shown in Figure 6

[0059] The obtained self-powered deep ultraviolet photodetector of quartz / β-Ga2O3 / CuPc is similar to example 1.

[0060] Example 5

[0061] ​The deep ultraviolet detector device is built by magnetron sputtering. The electrode is prepared by magnetron sputtering: Au / Ti electrode with the length and width of 0.9 cm x 0.2 cm is prepared on the β-Ga2O3 film of the prepared quartz / β-Ga2O3 / CuPc photoelectrochemical chip, and Au electrode with the length and width of 0.9 cm x 0.2 cm is prepared on the CuPc film. Compared with the point electrode, the strip electrode is more conducive to carrier transport, and the positions of the two electrodes are strictly controlled to be 0.2 cm apart and on the same horizontal line. The self-powered deep ultraviolet photodetector based on quartz

[0062] The photoelectric performance of the self-powered deep ultraviolet photodetector based on quartz

[0063] In order to explore the stability of the photodetector in harsh environments, the photoelectric performance is tested at room temperature, 50 DEG C, 100 DEG C and 150 DEG C, and the I-t curve is shown in Figure 5

[0064] The self-powered deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc has stable performance, high sensitivity, small dark current, solar blind characteristics, zero power consumption, high photocurrent in high temperature environment, and can monitor the deep ultraviolet spectrum of 220 nm-280 nm.

[0065] Obviously, the above examples are only examples for clearly illustrating, but not limit the embodiments. Any modification, equivalent replacement, improvement made on the basis of the above description within the method and principles of the present application should be included in the protection scope of the present application. It is not necessary and impossible to enumerate all the embodiments. The obvious changes or changes derived therefrom are still within the protection scope of the present application.​

Claims

1. A deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc self-powered power supply, characterized in that, The detector comprises a β-Ga2O3 thin film, a quartz substrate, a CuPc thin film, an Au / Ti electrode, and an Au electrode; The β-Ga2O3 film is located above the quartz substrate, the CuPc film is located above the Ga2O3 film, the Au / Ti electrode is located above the β-Ga2O3 film, and the Au electrode is located above the CuPc film.

2. The deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc self-powered system according to claim 1, characterized in that, The thickness of the β-Ga2O3 film is 1110nm~1125nm, the thickness of the CuPc film is 190nm~210nm, the surface area of ​​the CuPc film is 50% of the surface area of ​​the β-Ga2O3 film, and the length and width of the Au / Ti electrode and the Au electrode are 0.7cm~0.9cm×0.1cm~0.4cm.

3. The method for fabricating a deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc self-powered material according to any one of claims 1 to 2, characterized in that, It has the following steps: (1) Preparation of β-Ga2O3 / CuPc thin films: Gallium oxide thin films were grown on quartz using metal-organic chemical vapor deposition (MOCVD) at 850℃~860℃ for 60min~90min. Half of the prepared film was covered with hot melt adhesive for later use. Then, 0.5g~2g of CuPc solid powder was weighed using an electronic balance and added to 0.5L~1L of ethanol solution. The mixture was stirred with a magnetic stirrer for 1h~1.5h to fully disperse the CuPc powder in the ethanol solution, resulting in a CuPc dispersion of 1mg / ml~2mg / ml. A spin coater was used in a mode of 3000 r / s to 4000 r / s, with each spin coat lasting 40 to 60 seconds. The CuPc dispersion was then spin-coated onto the prepared film. The film was then heated on a heating stage at 90 to 100°C for 10 to 20 minutes to remove the hot melt adhesive. (2) Fabrication of a deep ultraviolet detector based on a quartz / β-Ga2O3 / CuPc photoelectrochemical chip: A deep ultraviolet (DUV) photodetector was constructed using magnetron sputtering. Electrodes were fabricated by magnetron sputtering: Au / Ti electrodes were prepared on the β-Ga₂O₃ / CuPc thin film, with dimensions of 0.7-0.9 cm × 0.1-0.4 cm. Au electrodes were prepared on the CuPc thin film, also with dimensions of 0.7-0.9 cm × 0.1-0.4 cm. The distance between the Au / Ti and Au electrodes was 0.1-0.2 cm, and they were on the same horizontal line. The photoelectric performance of the self-powered quartz / β-Ga₂O₃ / CuPc DUV photodetector was tested using a Keithley 2400 and 6487.

4. The application of the detector prepared by the method of fabrication of a deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc self-powered power supply according to claim 3 in deep ultraviolet detection.

5. The method for fabricating a deep ultraviolet photodetector based on quartz / β-Ga2O3 / CuPc self-powered system according to claim 3, characterized in that... The detector corresponds to the deep ultraviolet spectrum in the 220 nm-280 nm band and operates with zero power consumption.

Images