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CN-122028633-A - Two-dimensional tin-based perovskite field effect transistor based on small molecule doping and preparation method and application thereof

CN122028633ACN 122028633 ACN122028633 ACN 122028633ACN-122028633-A

Abstract

The invention discloses a two-dimensional tin-based perovskite field effect transistor based on small molecular doping and a preparation method and application thereof, and belongs to the technical field of photoelectric materials and semiconductor devices. The method comprises the following steps of coating a 4-fluorophenylethyl tin iodide perovskite precursor liquid on the surface of a substrate, then carrying out annealing treatment to obtain a 4-fluorophenylethyl tin iodide perovskite film, evaporating a small molecular doping layer on the surface of the 4-fluorophenylethyl tin iodide perovskite film by adopting a vacuum evaporation coating method, enabling the small molecular doping layer and the 4-fluorophenylethyl tin iodide perovskite film to form a heterojunction structure, and depositing a metal source electrode and a metal drain electrode on the surface of the heterojunction structure to obtain the two-dimensional tin-based perovskite field effect transistor based on small molecular doping. The method solves the problem of insufficient charge transport capacity of the existing two-dimensional tin-based perovskite caused by the insulativity of large-volume organic cations.

Inventors

  • WU ZHONGBIN
  • Zai Xiaohan
  • HUANG WEI

Assignees

  • 西北工业大学

Dates

Publication Date
20260512
Application Date
20260210

Claims (10)

  1. 1. The preparation method of the two-dimensional tin-based perovskite field effect transistor based on small molecule doping is characterized by comprising the following steps of: Coating 4-fluorophenylethyl tin iodide perovskite precursor liquid on the surface of a substrate, and then carrying out annealing treatment to obtain a 4-fluorophenylethyl tin iodide perovskite film; Evaporating a small molecular doping layer on the surface of the 4-fluorophenylethyl tin iodide perovskite film by adopting a vacuum evaporation coating method, so that the small molecular doping layer and the 4-fluorophenylethyl tin iodide perovskite film form a heterojunction structure; And depositing a metal source electrode and a metal drain electrode on the surface of the heterojunction structure to obtain the two-dimensional tin-based perovskite field effect transistor based on small molecular doping.
  2. 2. The method for preparing the two-dimensional tin-based perovskite field effect transistor based on small molecular doping according to claim 1, wherein the substrate is sequentially washed in absolute ethyl alcohol, a silicon-based cleaning agent, deionized water and isopropanol before the 4-fluorophenethyl tin iodide perovskite precursor liquid is dripped, and the washed substrate is subjected to drying treatment and then ozone-Ultraviolet (UV) treatment.
  3. 3. The preparation method of the two-dimensional tin-based perovskite field effect transistor based on small molecular doping, which is characterized in that the 4-fluorophenylethyl tin iodide perovskite precursor liquid coating is obtained by dissolving 4-fluorophenylethyl amine iodide, stannous iodide and tin compensator tin powder in an organic solvent and stirring; The mol ratio of the tin powder of the tin compensator to the stannous iodide is 0.01-0.05:1; the concentration of the 4-fluorophenylethyl tin iodide perovskite precursor solution is 0.18-0.22M; The organic solvent is a mixed solvent of N, N-dimethylformamide and dimethyl sulfoxide, and the volume ratio of the N, N-dimethylformamide to the dimethyl sulfoxide is (3.5-4.5): 1.
  4. 4. The preparation method of the two-dimensional tin-based perovskite field effect transistor based on small molecule doping, which is characterized in that the 4-fluorophenylethyl tin iodide perovskite precursor liquid is prepared at room temperature in nitrogen atmosphere; the substrate is an n-type heavily doped silicon wafer with a SiO 2 dielectric layer deposited on the surface.
  5. 5. The preparation method of the two-dimensional tin-based perovskite field effect transistor based on small molecule doping is characterized in that a method for coating 4-fluorophenylethyl tin iodide perovskite precursor on the surface of a substrate is spin coating, wherein the process parameters of the spin coating are that the rotating speed is 4000-6000 rpm, the acceleration is 4000-6000 rpm, the spin coating time is 45-60 s, and 100-300 mu L of antisolvent is dripped into 12-18 s; The temperature of the annealing treatment is 100-120 ℃ and the time is 10-12 min.
  6. 6. The preparation method of the two-dimensional tin-based perovskite field effect transistor based on small molecular doping is characterized in that the thickness of the 4-fluorophenylethyl tin iodide perovskite thin film is 40-80 nm, the thickness of the small molecular doping layer is 2-8 nm, and the thicknesses of the metal source electrode and the metal drain electrode are 30-35 nm.
  7. 7. The preparation method of the two-dimensional tin-based field effect transistor based on small molecule doping as claimed in claim 1, wherein the specific process of evaporating the small molecule doping layer on the surface of the 4-fluorophenylethyl tin iodide perovskite thin film by adopting a vacuum evaporation coating method is as follows: Evaporating a small molecular doping agent on the surface of a 4-fluorophenylethyl tin iodide perovskite film under the condition of 1.0X10 -5 -5.0×10 -4 Pa to form a small molecular doping layer; The small molecular dopants are NDP-9 and HAT-CN, and the vapor deposition rate is 0.1-0.15A/s.
  8. 8. The preparation method of the two-dimensional tin-based perovskite field effect transistor based on small molecular doping is characterized in that the metal source electrode and the metal drain electrode are Cr electrodes, and the specific process of depositing the metal source electrode and the metal drain electrode is that when the vacuum degree is smaller than 10 -5 Pa, the current is evaporated by 102-112A, the evaporation rate is 0.3A/s, and Cr is deposited by using a mask plate as the metal source electrode and the metal drain electrode of the transistor.
  9. 9. A two-dimensional tin-based perovskite field effect transistor based on small molecule doping, which is characterized in that the transistor is prepared by adopting the preparation method of any one of claims 1-8.
  10. 10. Use of a two-dimensional tin-based perovskite field effect transistor based on small molecule doping as claimed in claim 9 in low power integrated circuits, optoelectronic devices or smart sensors.

Description

Two-dimensional tin-based perovskite field effect transistor based on small molecule doping and preparation method and application thereof Technical Field The invention belongs to the technical field of photoelectric materials and semiconductor devices, and particularly relates to a two-dimensional tin-based perovskite field effect transistor based on small molecule doping, and a preparation method and application thereof. Background Perovskite materials are novel ionic crystal semiconductors, and have the advantages of continuous and adjustable band gap, high carrier mobility, low cost of solution preparation process and the like, so that the perovskite materials are widely focused in the fields of solar cells, light-emitting diodes, thin film transistors and the like in recent years. Tin-based perovskite exhibits higher carrier mobility due to lower effective mass. The two-dimensional tin-based perovskite forms a layered structure by introducing machine interval cations, and the stability of the material is obviously improved, so that the material has important application prospects in the fields of flexible electronics, integrated circuits and the like. However, in two-dimensional tin-based perovskite thin film field effect transistors, the insulating nature of the bulky organic spacer cations prevents efficient transport of carriers, resulting in lower overall mobility. Meanwhile, the layered structure weakens the reverse bond coupling effect between the Sn 5s and I5 p orbits, so that tin vacancy formation energy is relatively high, the free hole concentration which can be transported by the system is limited, and the influence of a defect state on the transport performance is amplified. In tin-based perovskite, tin vacancies act as the primary source of negatively charged shallow level defect centers, trapping positively charged free holes. The trapped carriers require additional energy excitation (e.g., photoexcitation or thermal activation) to be released from the trap and to re-participate in transport. While the "capture" and "de-capture" processes occur only on the microsecond scale, this phenomenon delays drift transport and reduces overall carrier mobility. Disclosure of Invention The invention aims to provide a two-dimensional tin-based perovskite field effect transistor based on small molecular doping, and a preparation method and application thereof, which are used for solving the problem of insufficient charge transport capacity of the existing two-dimensional tin-based perovskite caused by the insulativity of large-volume organic cations. In order to achieve the above purpose, the invention is realized by adopting the following technical scheme: the invention discloses a preparation method of a two-dimensional tin-based perovskite field effect transistor based on small molecule doping, which comprises the following steps: Coating 4-fluorophenylethyl tin iodide perovskite precursor liquid on the surface of a substrate, and then carrying out annealing treatment to obtain a 4-fluorophenylethyl tin iodide perovskite film; Evaporating a small molecular doping layer on the surface of the 4-fluorophenylethyl tin iodide perovskite film by adopting a vacuum evaporation coating method, so that the small molecular doping layer and the 4-fluorophenylethyl tin iodide perovskite film form a heterojunction structure; And depositing a metal source electrode and a metal drain electrode on the surface of the heterojunction structure to obtain the two-dimensional tin-based perovskite field effect transistor based on small molecular doping. Further, before the 4-fluorophenylethyl tin iodide perovskite precursor liquid is dripped, the substrate is sequentially washed in absolute ethyl alcohol, a silicon-based cleaning agent, deionized water and isopropanol, and the washed substrate is subjected to drying treatment and then ozone-Ultraviolet (UV) treatment. Further, the 4-fluorophenylethyl tin iodide perovskite precursor liquid is prepared by dissolving 4-fluorophenylethyl amine iodide, stannous iodide and tin compensator tin powder in an organic solvent and stirring; The mol ratio of the tin powder of the tin compensator to the stannous iodide is 0.01-0.05:1; the concentration of the 4-fluorophenylethyl tin iodide perovskite precursor solution is 0.18-0.22M; The organic solvent is a mixed solvent of N, N-dimethylformamide and dimethyl sulfoxide, and the volume ratio of the N, N-dimethylformamide to the dimethyl sulfoxide is (3.5-4.5): 1. Further, the 4-fluorophenylethyl tin iodide perovskite precursor solution is prepared at room temperature in a nitrogen atmosphere; the substrate is an n-type heavily doped silicon wafer with a SiO 2 dielectric layer deposited on the surface. Further, the method for coating the 4-fluorophenylethyl tin iodide perovskite precursor liquid on the surface of the substrate is a spin coating method, wherein the process parameters of the spin coating method are that the rotating speed