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CN-117645314-B - Amorphous gallium oxide nano-sheet, UV-Vis-NIR wide-spectrum photoelectric detector and preparation method

CN117645314BCN 117645314 BCN117645314 BCN 117645314BCN-117645314-B

Abstract

The invention provides an amorphous gallium oxide nano-sheet, a preparation method thereof and a UV-Vis-NIR wide-spectrum photoelectric detector. The amorphous gallium oxide nano-sheet prepared by the method is nano-sheet with the size of about a few micrometers and the thickness of about 10-40 nm. The amorphous gallium oxide nano-sheet is an amorphous nano-sheet with low duty ratio tetrahedral center Ga, and has the performance advantages of wide spectrum absorption and spin polarization. The amorphous gallium oxide nano-sheet, the conductive silicon chip and the graphene are assembled into the photoelectric detector with the vertical structure, and a pair of back-to-back rectifying junctions formed by the Schottky junctions and the p-n junctions in series connection are formed, so that the photoelectric detector has lower dark current. The photodetector with a vertical structure based on the amorphous gallium oxide shows excellent UV-Vis-NIR broad spectrum photodetection performance.

Inventors

  • HONG XUN
  • YU JUNLING
  • WU GENG
  • YANG QING

Assignees

  • 中国科学技术大学

Dates

Publication Date
20260505
Application Date
20231019

Claims (9)

  1. 1. The preparation method of the amorphous gallium oxide nano-sheet comprises the following steps: Mixing, calcining and washing the gallium acetylacetonate and KNO 3 powder to obtain amorphous gallium oxide nano-sheets; The tetrahedral center Ga of the amorphous gallium oxide nano-sheet is lower than the crystal beta-Ga 2 O 3 ; the amorphous gallium oxide nanoplatelets have a bandgap smaller than that of crystalline β -Ga 2 O 3 and have an increased gap state; The amorphous gallium oxide nano-sheet has a widened light absorption range of 254-1064 nm.
  2. 2. The preparation method of the gallium acetylacetonate, according to claim 1, wherein the mass ratio of the gallium acetylacetonate to the KNO 3 is 1 (1.5-25).
  3. 3. The preparation method according to claim 1, wherein the calcination temperature is 190-260 ℃, and the calcination atmosphere is air; and heating to the temperature required by calcination at the heating rate of 2-5 ℃ per minute, and preserving heat for 1-1.5 h.
  4. 4. An amorphous gallium oxide nanoplatelet, characterized in that it is produced by the production method according to any one of claims 1 to 3; The size of the amorphous gallium oxide nano-sheet is 1-2 mu m, and the thickness of the amorphous gallium oxide nano-sheet is 10-40 nm; The tetrahedral center Ga of the amorphous gallium oxide nano-sheet is lower than the crystal beta-Ga 2 O 3 ; the amorphous gallium oxide nanoplatelets have a bandgap smaller than that of crystalline β -Ga 2 O 3 and have an increased gap state; The amorphous gallium oxide nano-sheet has a widened light absorption range of 254-1064 nm.
  5. 5. A UV-Vis-NIR broad spectrum photodetector comprising a bottom electrode; A light responsive layer disposed on the bottom electrode; A top electrode overlying the light responsive layer; The light response layer is an amorphous gallium oxide nano-sheet prepared by the preparation method of any one of claims 1-3 or an amorphous gallium oxide nano-sheet of claim 4.
  6. 6. The UV-Vis-NIR wide-spectrum photodetector according to claim 5, wherein said bottom electrode is a P-type silicon wafer, the thickness of the P-type silicon wafer is 200-500 μm, and the dimensions of the silicon wafer are (0.4X0.4) cm to (2X 2) cm; the top electrode is graphene, and the thickness of the top electrode is 0.340-0.350 nm; the thickness of the light response layer is 0.020-3 mu m.
  7. 7. The UV-Vis-NIR broad spectrum photodetector of claim 5, wherein said broad spectrum photodetector has the ability to detect UV-Vis-NIR 254-1064 nm range light; has a dark current as low as 63 pA under forward bias; has a fast response speed of τ ascending to <30 ms, τ Descent down <50 ms.
  8. 8. The UV-Vis-NIR broad spectrum photodetector of claim 5, wherein schottky junctions and P-n junctions are formed at the contact interface of the amorphous gallium oxide nanoplatelets with graphene and P-type silicon, respectively; The schottky junction and the p-n junction are connected in series to form a pair of rectifying junctions back-to-back.
  9. 9. A method for preparing the UV-Vis-NIR broad spectrum photodetector of any one of claims 5 to 8, comprising the steps of: spin-coating an ethanol suspension of the amorphous gallium oxide nano-sheet with the concentration of 2-15 mg/mL on a bottom electrode to form a light response layer; and covering the top electrode on the light response layer to obtain the wide-spectrum photoelectric detector.

Description

Amorphous gallium oxide nano-sheet, UV-Vis-NIR wide-spectrum photoelectric detector and preparation method Technical Field The invention belongs to the technical field of semiconductor advanced materials and ultraviolet-visible light-near infrared broad spectrum photoelectric detection, and particularly relates to an amorphous gallium oxide nano-sheet, a UV-Vis-NIR broad spectrum photoelectric detector and a preparation method thereof. Background The ultraviolet-visible-near infrared wide spectrum photoelectric detector has wide application in the fields of environmental monitoring, optical communication, image sensing and the like. A variety of semiconductor materials, such as sulfides, selenides, and tellurides, have been developed as optically responsive layers for broad spectrum detectors. However, they are difficult to achieve excellent overall performance due to their respective drawbacks such as environmental instability, complicated preparation processes or toxicity. The wide bandgap metal oxide semiconductors offer an option for photodetectors due to their non-toxicity, low energy loss, high stability, and cost effectiveness. However, the use of oxide semiconductors in broad spectrum photodetection is often limited by limited light absorption due to their large intrinsic band gap. To overcome this limitation, it is urgent to realize a high-performance metal oxide broadband photodetector, to expand the light absorption range and to accelerate the separation of photogenerated carriers. Therefore, the metal oxide with simple preparation process, no toxicity, low cost and wide spectral response and high-efficiency carrier separation is provided, and the UV-Vis-NIR wide spectral photoelectric detector with high detection rate, low dark current and high response speed can be realized. Disclosure of Invention In view of the above, the present invention aims to provide an amorphous gallium oxide nano-sheet, a UV-Vis-NIR broad spectrum photodetector and a preparation method thereof, wherein the preparation method of the amorphous gallium oxide nano-sheet has the advantages of simplicity, no toxicity and low cost, the amorphous gallium oxide nano-sheet of the present invention has the properties of wide absorption range and spin polarization, and the photodetector based on the amorphous gallium oxide nano-sheet of the present invention has the advantages of wide spectrum detection range, high detection rate, rapid response speed and low dark current. The invention provides a preparation method of an amorphous gallium oxide nano-sheet, which comprises the following steps: Mixing the gallium acetylacetonate with KNO 3 powder, calcining and washing to obtain the amorphous gallium oxide nano-sheet. Preferably, the mass ratio of the gallium acetylacetonate to the KNO 3 is 1 (1.5-25). Preferably, the calcination temperature is 190-260 ℃, and the calcination atmosphere is air; and heating to the temperature required by calcination at the heating rate of 2-5 ℃ per minute, and preserving heat for 1-1.5 h. The invention provides an amorphous gallium oxide nano-sheet, which is prepared by the preparation method according to the technical scheme; the size of the amorphous gallium oxide nano-sheet is 1-2 mu m, and the thickness of the amorphous gallium oxide nano-sheet is 10-40 nm. Preferably, the tetrahedral center Ga of the amorphous gallium oxide nano-sheet is lower than the crystal beta-Ga 2O3; the amorphous gallium oxide nanoplatelets have a bandgap smaller than that of crystalline β -Ga 2O3 and have an increased gap state; the amorphous gallium oxide nano-sheet has a widened light absorption range of 254-1064 nm. The invention provides a UV-Vis-NIR wide spectrum photodetector, which comprises a bottom electrode; A light responsive layer disposed on the bottom electrode; A top electrode overlying the light responsive layer; The light response layer is an amorphous gallium oxide nano-sheet prepared by the preparation method according to the technical scheme or the amorphous gallium oxide nano-sheet according to the technical scheme. Preferably, the bottom electrode is a P-type silicon wafer, the thickness of the P-type silicon wafer is 200-500 mu m, and the size of the silicon wafer is (0.4X0.4) cm to (2X 2) cm; the top electrode is graphene, and the thickness of the top electrode is 0.340-0.350 nm; The thickness of the light response layer is 0.020-3 mu m. Preferably, the wide-spectrum photoelectric detector has the capability of detecting light in a range of 254-1064 nm of UV-Vis-NIR; has a dark current as low as 63pA under forward bias; has a fast response speed τ ascending to <30ms,τ Descent down <50ms. Preferably, a Schottky junction and a P-n junction are respectively formed at the contact interface of the amorphous gallium oxide nano-sheet, the graphene and the P-type silicon; The schottky junction and the p-n junction are connected in series to form a pair of rectifying junctions back-to-back. The invention