A rare earth metal oxide Nd 2 O 3 Low-power consumption and high-performance ultraviolet detector and preparation method thereof

Abstract

A low-power consumption, high-performance ultraviolet detector based on rare earth metal oxide Nd2O3 and a preparation method thereof, belonging to the field of ultraviolet photoelectric detection technology. It is composed of a glass substrate with a FTO conductive film etched from a part of the FTO layer, an Ag bottom electrode prepared on the substrate surface, a Nd2O3 nanofilm photosensitive layer prepared on the substrate surface by a sol-gel method, and an Ag top electrode prepared on the surface of the Nd2O3 nanofilm photosensitive layer above the etched area of ​​the FTO layer. The Ag bottom electrode is not in electrical contact with the Nd2O3 nanofilm photosensitive layer, and the Ag top electrode-Nd2O3 nanofilm photosensitive layer-FTO conductive film-Ag bottom electrode constitutes an electrical circuit. The device prepared by the present invention has extremely low dark current, and at the same time has good response in the ultraviolet band, has extremely low power consumption in the standby state without light, and has high ultraviolet photoelectric detection performance, and can be used as a low-power consumption, high-performance ultraviolet detector.

Description

Technical Field

[0001] The invention belongs to the field of ultraviolet photoelectric detection technology, and specifically relates to a rare earth metal oxide Nd 2 O 3 A low-power consumption and high-performance ultraviolet detector and a preparation method thereof. Background Art

[0002] High-sensitivity ultraviolet photodetectors have important applications in the fields of cell detection, remote control, environmental monitoring, and optoelectronic integrated circuits. With the continuous advancement of semiconductor materials and device preparation processes, the new generation of wide-bandgap semiconductor ultraviolet detectors have overcome the shortcomings of traditional photomultiplier tube devices such as complex structure, large size, and high energy consumption, and have become a hot topic in the field of ultraviolet detection technology. At the same time, the visible blindness of wide-bandgap materials themselves effectively compensates for the disadvantage that silicon-based devices cannot shield visible light by themselves, and there are many types of wide-bandgap materials, especially including a variety of oxide materials such as ZnO, TiO 2 , Ga 2 O 3 、Nd 2 O 3 These materials have stable properties, diverse preparation methods and low costs, and have important application value.

[0003] With the continuous development of science and technology and the emergence of energy problems, how to use resources more effectively has become a problem of widespread concern in various application fields. Therefore, while improving the basic performance parameters of ultraviolet detectors such as responsiveness and detection sensitivity, various application fields have gradually focused on reducing device energy consumption, such as putting the device in a low-power state when in standby mode. High-performance ultraviolet photodetectors often have high process requirements, which increases the experimental cost while raising the research threshold. In order to avoid excessive experimental costs, improve resource utilization, and alleviate energy shortages, the development of a high-performance, low-power ultraviolet detector with low manufacturing process requirements has gradually become a new demand. Summary of the invention

[0004] The present invention aims to provide a rare earth metal oxide Nd 2 O 3 A low-power consumption and high-performance ultraviolet detector and a preparation method thereof.

[0005] The light sensitive layer of the ultraviolet detector of the present invention is Nd 2 O 3 Nanofilms are prepared by spin coating rare earth metal oxides Nd on etched FTO (fluorine-doped tin oxide) conductive glass. 2 O 3 Precursor solution to prepare ultraviolet photodetector.

[0006] The rare earth metal oxide Nd 2 O 3 The invention discloses a low-power high-performance ultraviolet detector, which is characterized by: from bottom to top, a glass substrate with a FTO conductive film etched from a part of the FTO layer, an Ag bottom electrode prepared on the surface of the glass substrate with the FTO conductive film, and a Nd 2 O 3 Nanofilm photosensitive layer, Nd above the etched area of ​​the FTO layer 2 O 3 The Ag top electrode is prepared on the surface of the nanofilm photosensitive layer, and the Ag bottom electrode is not connected with Nd 2 O 3 Nanofilm photosensitive layer electrical contact, Ag top electrode-Nd 2 O 3 The nanofilm photosensitive layer-FTO conductive film-Ag bottom electrode constitutes an electrical circuit; wherein the thickness, length and width of the glass substrate with the FTO conductive film are 1-3 mm, 15-30 mm and 15-30 mm respectively, and the Nd 2 O 3 The thickness of the nanofilm photosensitive layer is 80-160 nm, the thickness, length and width of the Ag bottom electrode and the Ag top electrode are 1-2 mm, 2-3 mm and 1-2 mm respectively; the structure of the device is as follows Figure 1 shown.

[0007] The rare earth metal oxide Nd 2 O 3 The main working principle of the low-power high-performance UV detector is that in the dark state, the thin film device is in a high resistance state, which greatly reduces the dark current and the power consumption of the UV detector in standby mode. 2 O 3 New photogenerated carriers in the nanofilm photosensitive layer are constantly excited, thereby increasing the number of carriers, ultimately giving the device a higher gain and photocurrent, resulting in a large light-dark suppression ratio and improving the detection capability of the UV detector.

[0008] The rare earth metal oxide Nd 2 O 3 The preparation method of the low-power high-performance ultraviolet detector comprises the following steps:

[0009] (1) Cleaning the substrate

[0010] The FTO layer of a certain width is etched away along one side of the glass substrate with the FTO conductive film in a hydrochloric acid solution with zinc powder added, so as to expose the glass substrate underneath; the etched glass substrate with the FTO conductive film is then placed in acetone, ethanol and deionized water for ultrasonic cleaning for 10 to 20 minutes, dried with nitrogen and then placed in an ultraviolet ozone environment for treatment for 10 to 20 minutes to obtain a clean glass substrate with the FTO conductive film;

[0011] (2) Preparation of Nd 2 O 3 Nanofilm

[0012] First, prepare Nd 2 O 3 Sol: 0.01-0.08 g Nd 2 O 3 Add to 3-8 ml of ethylene glycol methyl ether, sonicate for 1-3 hours, let stand for 20-30 hours, extract the supernatant, and filter to obtain Nd 2 O 3 Precursor solution; on the opposite side of the FTO etched area, a glass substrate with a certain width of FTO conductive film is covered with tape, and Nd is spin-coated on the glass substrate with FTO conductive film and the tape surface by spin coating. 2 O 3 The precursor solution is formed into a thin film, which is then dried at 100-150°C for 10-15 minutes; after the substrate is cooled to room temperature, the above "spin coating-drying" steps are repeated 1-5 times; finally, the tape is removed, and the film is sintered at 500-600°C for 1-3 hours, thereby obtaining a Nd film with a thickness of 80-160 nm on a glass substrate with a FTO conductive film. 2 O 3 Nanofilm photosensitive layer, the surface of the area originally covered by the tape on the glass substrate with FTO conductive film is not covered by Nd 2 O 3 The nano-thin film photosensitive layer is covered and used to prepare the Ag bottom electrode;

[0013] (3) Preparation of Ag electrode

[0014] Using a mask with two hollow rectangular patterns, Nd 2 O 3 The surface of the nanofilm photosensitive layer and the surface of the glass substrate with the FTO conductive film exposed after removing the tape in step (2) are dotted with Ag conductive glue and Ag wires are led out. After drying, Ag top electrode and Ag bottom electrode are obtained respectively. The Ag bottom electrode does not contact with Nd 2 O 3 Direct electrical contact of nanofilm photosensitive layer, Ag top electrode-Nd 2 O3 Nano film photosensitive layer-FTO conductive film-Ag bottom electrode constitutes an electrical circuit, thereby obtaining the rare earth metal oxide Nd 2 O 3 Low power consumption and high performance UV detector BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 : A schematic diagram of the structure of the device of the present invention;

[0016] Figure 2 :Nd of the present invention 2 O 3 Current-voltage characteristic curve of UV detection device.

[0017] like Figure 1 As shown, the names of the components are: Ag bottom electrode 1, glass substrate 2, FTO conductive film 3, Nd 2 O 3 Nano film photosensitive layer 4 and Ag top electrode 5.

[0018] like Figure 2 As shown, the Nd 2 O 3 When the layer thickness is 120nm, the dark current is only -4.68×10 -11 A, in the 280nm band, the light intensity is 15μW / cm 2 The photocurrent under the condition of -15V bias is -7.75×10 -8 A, at this time, the light-dark suppression ratio has three orders of magnitude and reaches 1.66×10 3 . DETAILED DESCRIPTION

[0019] Embodiment 1:

[0020] (1) Substrate processing

[0021] A glass substrate with an FTO conductive film (the thickness, length and width of the glass substrate are 2 mm, 20 mm and 20 mm, respectively, and the thickness of the FTO conductive film is 120 nm) is etched along one side to remove a certain width of the FTO layer (the length and width of the etched FTO layer are 20 mm and 5 mm, respectively) to expose the glass substrate underneath; then the etched glass substrate with the FTO conductive film is placed in acetone, ethanol and deionized water for ultrasonic cleaning for 15 minutes in turn, dried with nitrogen and then placed in an ultraviolet ozone environment for treatment for 15 minutes, thereby obtaining a clean glass substrate with the FTO conductive film; finally, a tape with a length of 20 mm and a width of 5 mm is adhered to the surface of the opposite side of the etched area of ​​the substrate.

[0022] (2)Nd2 O 3 Preparation of nanofilm

[0023] First, prepare Nd 2 O 3 Precursor solution, 0.06 g Nd 2 O 3 Add it into a glass bottle containing 5 ml of ethylene glycol methyl ether solution, ultrasonicate the solution for 2 hours, let it stand for 24 hours, extract the supernatant, and filter it to obtain Nd 2 O 3 Precursor solution; then spin-coat Nd on the surface of the substrate and tape after cleaning in step (1) 2 O 3 The precursor solution is spin-coated to form a thin film at a speed of 3000 rpm for 30 seconds; then the substrate is dried at 100°C for 10 minutes, and the substrate is cooled to room temperature, and the above "spin coating-drying" steps are repeated twice. After the solvent evaporates and the substrate is cooled to room temperature, the tape is peeled off; finally, the obtained glass substrate with FTO conductive film is sintered at 550°C for 2 hours, thereby obtaining Nd on the surface of the glass substrate with FTO conductive film. 2 O 3 Nano-thin film photosensitive layer, thickness is 120nm.

[0024] (3) Preparation of Ag electrode

[0025] Using a mask with two hollow rectangular patterns, Nd 2 O 3 The surface of the nanofilm photosensitive layer and the surface of the glass substrate with the FTO conductive film exposed after the tape was removed in step (2) were dotted with Ag conductive glue and Ag wires were drawn out. After drying at 75° C. for 15 minutes, Ag top electrode and Ag bottom electrode were obtained, respectively. The thickness, length and width of the Ag top electrode and the Ag bottom electrode were 1 mm, 2 mm and 1 mm, respectively. The Ag bottom electrode did not contact the Nd 2 O 3 Direct electrical contact of nanofilm photosensitive layer, Ag top electrode-Nd 2 O 3 Nano film photosensitive layer-FTO conductive film-Ag bottom electrode constitutes an electrical circuit, thereby obtaining the rare earth metal oxide Nd 2 O 3 Low power consumption and high performance UV detector

[0026] Based on rare earth metal oxide Nd 2 O 3 After the ultraviolet photodetector device is prepared, the light and dark current-voltage characteristics of the device are tested, such as Figure 2As shown. In the dark state with a bias voltage of -15V, the dark current of the device is -4.68×10 -11 A; at a wavelength of 280nm and a light intensity of 15μW / cm 2 Under the condition of -15V bias, the photocurrent of the device is -7.75×10 -8 A, the light-dark suppression ratio of the device is 1.66×10 3 It shows that the device prepared by the present invention has extremely low dark current and good response in the ultraviolet band, which means that the present invention has extremely low power consumption in the standby state without light and has high ultraviolet photoelectric detection performance, and can be used as a low-power and high-performance ultraviolet detector.

Claims

1. A method for preparing a low-power, high-performance ultraviolet detector based on rare earth metal oxide Nd2O3, the steps of which are as follows: (1) Cleaning the substrate The FTO layer of a certain width is etched off along one side of the glass substrate with the FTO conductive film to expose the glass substrate underneath; the etched glass substrate with the FTO conductive film is then placed in acetone, ethanol and deionized water for ultrasonic cleaning for 10 to 20 minutes, dried with nitrogen and placed in an ultraviolet ozone environment for 10 to 20 minutes to obtain a clean glass substrate with the FTO conductive film; (2) Preparation of Nd2O3 nanofilm First, prepare Nd2O3 sol: add 0.01-0.08 g Nd2O3 to 3-8 ml ethylene glycol methyl ether, ultrasonicate for 1-3 hours, stand for 20-30 hours, extract the supernatant, and filter to obtain Nd2O3 precursor solution; cover a glass substrate with a certain width of FTO conductive film on the opposite side surface of the FTO etched area with tape, spin-coat the glass substrate with FTO conductive film and the tape surface with Nd2O3 precursor solution to form a film, and then dry at 100-150°C for 10-15 minutes; after the substrate is cooled to room temperature, repeat the above "spin coating-drying" steps 1-5 times; finally, remove the tape, and sinter at 500-600°C for 1-3 hours, so as to obtain a Nd2O3 nanofilm photosensitive layer on the glass substrate with FTO conductive film; (3) Preparation of Ag electrode Using a mask with two hollow rectangular patterns, Ag conductive glue is spot-coated on the surface of the Nd2O3 nanofilm photosensitive layer above the FTO etched area and on the surface of the glass substrate with the FTO conductive film exposed after removing the tape in step (2), and Ag wires are led out. After drying, Ag top electrode and Ag bottom electrode are obtained respectively. The Ag bottom electrode is not in direct electrical contact with the Nd2O3 nanofilm photosensitive layer. The Ag top electrode-Nd2O3 nanofilm photosensitive layer-FTO conductive film-Ag bottom electrode constitute an electrical circuit, thereby obtaining a low-power consumption and high-performance ultraviolet detector based on the rare earth metal oxide Nd2O3.

2. A low-power, high-performance ultraviolet detector based on rare earth metal oxide Nd2O3, characterized in that: The method is prepared by the method of claim 1.

3. A low-power consumption and high-performance ultraviolet detector based on rare earth metal oxide Nd2O3 as claimed in claim 2, characterized in that: The thickness, length and width of the glass substrate with FTO conductive film are 1-3 mm, 15-30 mm and 15-30 mm respectively, the thickness of the Nd2O3 nanofilm photosensitive layer is 80-160 nm, the thickness, length and width of the Ag bottom electrode and the Ag top electrode are 1-2 mm, 2-3 mm and 1-2 mm respectively.

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