Photoelectric detector capable of simultaneously realizing ultraviolet and infrared light detection and display and preparation method thereof

Abstract

The invention belongs to the technical field of photoelectric detectors, and particularly relates to a photoelectric detector capable of simultaneously detecting and displaying ultraviolet light and infrared light and a preparation method of the photoelectric detector. The structure of the photoelectric detector comprises a wavelength conversion substrate formed by rare earth ion Er < 3 + > doped fluoride glass, a bottom electrode formed by ITO or FTO metal oxide, an interface layer formed by PEIE, a photosensitive layer formed by a P3HT: PC71BM bulk heterojunction film, and a top electrode formed by Ag or Au from bottom to top. The transparent conductive layer and the metal top electrode form a vertical charge transmission channel. Direct display from ultraviolet / infrared to visible light can be realized through the efficient up-conversion and down-conversion characteristics of the Er < 3 + > doped fluoride glass; the photosensitive layer generates light current by absorbing the converted visible light, and synchronous output of photoelectric signals is achieved. The device shows excellent detection-display synergistic performance in wavebands of 355 nm, 980 nm and 1550 nm, the structure is compact, and an external display module is not needed.

Description

Technical Field

[0001] The present invention belongs to the technical field of photoelectric detection devices, and specifically relates to a photoelectric detector and a method for preparing the same Background Art

[0002] Traditional photodetectors require silicon-based circuits or external LED modules for signal display, resulting in high device complexity and difficulty achieving multi-band compatibility. While reported infrared detectors based on upconversion nanoparticles achieve single-band display, they suffer from low conversion efficiency and incompatibility with the ultraviolet band. Summary of the Invention

[0003] The object of the present invention is to provide a photoelectric detector capable of simultaneously detecting and displaying ultraviolet and infrared light and a method for preparing the same.

[0004] The present invention provides a photodetector capable of simultaneously detecting and displaying ultraviolet and infrared light. The structure thereof comprises, from bottom to top, a wavelength conversion substrate, a bottom electrode, an interface layer, a photosensitive layer, and a top electrode; wherein:

[0005] The wavelength conversion substrate is a fluoride glass doped with rare earth ions Er3+; the fluoride glass includes but is not limited to fluoroindiumate glass, fluorozirconate glass and fluoroaluminate glass, and the rare earth ion Er3+ doping concentration is 0.1 mol%-10 mol%.

[0006] The bottom electrode is ITO or FTO transparent metal oxide with a thickness of 100-200nm;

[0007] The interface layer is PEIE;

[0008] The photosensitive layer is P3HT:PC 71 BM bulk heterojunction thin film, thickness is 200nm~500nm.

[0009] The top electrode is metal Ag or Au, and has a thickness of 100nm-200nm.

[0010] In the present invention:

[0011] The transparent conductive layer (ITO or FTO) and the metal top electrode (Ag or Au) form a vertical charge transfer channel;

[0012] The interface layer can reduce the ITO work function and improve the hole injection efficiency.

[0013] The photosensitive layer matches the converted visible light absorption spectrum.

[0014] The photodetector provided by the present invention regulates the Er in the substrate 3+ The doping concentration of Er is adjusted to achieve the conversion of ultraviolet and infrared light.3+ ] with a doping concentration of (0.1-10 mol%), achieving efficient down-conversion and up-conversion of ultraviolet (355nm→520 / 545nm) and infrared (980 / 1550nm→660nm).

[0015] The present invention also provides a method for preparing the multi-band compatible photoelectric detector, the specific steps of which are as follows:

[0016] (1) Substrate preparation: Er was prepared by melt quenching method 3+ For the doped fluoride glass substrate, mix the Er3+-doped fluoride glass batch evenly, place it in a platinum crucible, and melt it in an electric furnace at 850°C-1000°C for 15-30 minutes. Then, cast it onto a metal template preheated at 150°C-280°C. After the fluoride glass solidifies, transfer it to an annealing furnace at 200°C-250°C and anneal for 5-8 hours. The entire process is carried out in a nitrogen-protected glove box. The glass substrate is then cut into a certain size as needed.

[0017] (2) Bottom electrode deposition: A 100-200 nm ITO layer with a sheet resistance of ≤15 Ω / sq was prepared on the substrate surface using magnetron sputtering.

[0018] (3) Interface layer treatment: spin coating a 30 nm PEIE layer (rotation speed 2000-3000 rpm, time 30-60 s), annealing at 120-150 ° C for 10-20 min.

[0019] (4) Preparation of photosensitive layer: Spin coating of P3HT:PC71BM (1:1-1:1.5 wt%) chlorobenzene solution with a film thickness of 200 nm-500 nm.

[0020] (5) Top electrode evaporation: Vacuum thermal evaporation to deposit Ag electrode with a thickness of 100nm-200nm.

[0021] In the present invention, Er 3+ Fluoride-doped glass serves as both a substrate support and wavelength conversion function. Its highly efficient upconversion (1550nm to visible light) and downconversion (355nm to visible light) properties enable direct display of ultraviolet / infrared light to the visible. The photosensitive layer absorbs the converted visible light to generate a photocurrent, enabling simultaneous output of photoelectric signals. The device exhibits excellent detection-display synergy in the 355nm, 980nm, and 1550nm bands, is compact, and requires no external display module.

[0022] Beneficial effects of the present invention

[0023] Increase device integration: The substrate has both wavelength conversion and support functions, reducing the number of components by 50% compared to traditional discrete structures.

[0024] Improved dual-mode detection capability: covers a wide spectrum response from ultraviolet (355nm) to infrared (1550nm), with a responsivity of >1A / W@355nm and >8mA / W@1550nm.

[0025] Enhanced human-computer interaction: Real-time display of ultraviolet / infrared invisible light through red and green light (520 / 545 / 660nm) that can be recognized by the naked eye. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the structure of the photoelectric detector of the present invention.

[0027] Figure 2 This is the test data of the photoelectric detector that realizes ultraviolet / infrared light detection simultaneously prepared in Example 1. DETAILED DESCRIPTION

[0028] The present invention is further described below through embodiments in conjunction with the accompanying drawings.

[0029] Example 1:

[0030] 1. Substrate preparation: Er was prepared by melt quenching method 3+ Fluoride glass substrate doped with fluorine indium salt glass (composition: 40InF3-20ZnF2-20SrF2-20BaF2-5ErF3, mol%), 3+ The 30g batch of fluoride glass was mixed evenly, placed in a platinum crucible, and melted in an electric furnace at 850℃ for 30min. It was then poured onto a metal template preheated at 200℃. After the fluoride glass solidified, it was transferred to an annealing furnace at 250℃ and annealed for 5h. The entire process was carried out in a nitrogen-protected glove box. After annealing, it was cut into 15×15×1mm 3 substrate.

[0031] 2. Electrode deposition: A 100 nm ITO layer was prepared on the substrate surface by magnetron sputtering with a sheet resistance of ≤15Ω / sq.

[0032] 3. Interface treatment: spin coating a 30 nm PEIE layer (3000 rpm, 60 s) and annealing at 150 °C for 10 min.

[0033] 4. Preparation of photosensitive layer: Spin coating of P3HT:PC71BM (1:1 wt%) chlorobenzene solution with a film thickness of 300±20 nm.

[0034] 5. Top electrode deposition: Vacuum thermal evaporation deposition of 150nm Ag electrode, effective area 4mm 2 .

[0035] Test data

[0036] Under ultraviolet (355nm) and infrared (980nm, 1550nm) light, the device emits bright green and red light, and can clearly display the letters "SIOM".

[0037] Figure 2 In (a), the device is in the absence of Er 3+ When doped with fluoroindium salt glass, it has responsivity only in the visible light region;

[0038] Figure 2 In (b), when Er 3+ When doped with fluorine indium salt glass, the device emits bright green light in the ultraviolet (355nm), clearly displaying the letters "SIOM"; and with the help of Stokes luminescence, the device can achieve enhanced UV light response in the UV region of 250nm to 400nm, with a responsivity of approximately 1.5A / W@355nm.

[0039] Figure 2 In (c), when Er 3+ When doped with fluorine indium salt glass, the device emits bright red light and can clearly display the letters "SIOM"; under infrared (980nm, 1550nm) light, with the help of anti-Stokes luminescence, the device can obtain infrared light response with a responsivity of about 8mA / W@1550nm.

[0040] Example 2:

[0041] 1. Substrate preparation: Er was synthesized by melt quenching method 3+ Doped fluorine indium salt glass (composition: 40InF3-20ZnF2-20SrF2-200BaF2-5ErF3, mol%), cut into 15×15×1mm after annealing 3 substrate.

[0042] 2. Electrode deposition: A 100 nm ITO layer was prepared on the substrate surface by magnetron sputtering with a sheet resistance of ≤15Ω / sq.

[0043] 3. Interface treatment: spin coating a 30 nm PEIE layer (3000 rpm, 60 s) and annealing at 150 °C for 10 min.

[0044] 4. Preparation of photosensitive layer: Spin coating of P3HT:PC71BM (1:1.5 wt%) chlorobenzene solution with a film thickness of 300±20 nm.

[0045] 5. Top electrode deposition: Vacuum thermal evaporation deposition of 150nm Ag electrode, effective area 4mm 2 .

[0046] The test data situation is similar to that of Example 1.

Claims

1. A photoelectric detector capable of simultaneously detecting and displaying ultraviolet and infrared light, characterized in that: The structure from bottom to top is: wavelength conversion substrate, bottom electrode, interface layer, photosensitive layer, top electrode; among them: The wavelength conversion substrate is a fluoride glass doped with rare earth ion Er3+; the rare earth ion Er3+ doping concentration is 0.1mol% to 10mol%; The bottom electrode is ITO or FTO transparent metal oxide; The interface layer is PEIE; The photosensitive layer is P3HT:PC 71 BM bulk heterojunction thin film; The top electrode is metal Ag or Au; The transparent conductive layer and the metal top electrode form a vertical charge transfer channel.

2. The photodetector according to claim 1, wherein The fluoride glass is fluoroindiumate glass, fluorozirconate glass or fluoroaluminate glass.

3. The photodetector according to claim 1, wherein The bottom electrode has a thickness of 100-200 nm.

4. The photodetector according to claim 1, wherein The thickness of the photosensitive layer is 200nm-500nm.

5. The photodetector according to claim 1, wherein The thickness of the top electrode is 100nm-200nm.

6. The method for preparing a photodetector according to any one of claims 1 to 5, characterized in that: The specific steps are as follows: (1) Substrate preparation: Er was prepared by melt quenching method 3+ Doped fluoride glass substrate; the Er3+-doped fluoride glass batch material is mixed evenly, placed in a platinum crucible, and melted in an electric furnace at 850°C-1000°C for 15-30 minutes, and then poured onto a metal template preheated at 150°C-280°C. After the fluoride glass is solidified, it is transferred to an annealing furnace at a temperature of 200°C-250°C and annealed for 5-8 hours. The entire process is carried out in a nitrogen-protected glove box; and then the glass substrate is cut into a certain size as needed; (2) Bottom electrode deposition: A 100-200 nm ITO layer with a sheet resistance of ≤15 Ω / sq was prepared on the substrate surface using magnetron sputtering. (3) Interface layer treatment: spin coating PEIE layer, rotation speed 2000-3000 rpm, time 30-60 s, annealing at 100-150 ° C for 10-20 min; (4) Preparation of photosensitive layer: Spin coating P3HT:PC71BM chlorobenzene solution; P3HT:PC71BM = 1:1-1:1.5wt%; (5) Top electrode evaporation: Ag electrode is deposited by vacuum thermal evaporation.

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