CN-115988936-B - X-ray detector, functional unit thereof and preparation method

Abstract

The application relates to an X-ray detector and a functional unit and a preparation method thereof, which belong to the technical field of semiconductor photodetectors, wherein the surface of a circuit substrate is modified to ensure that the nucleation barrier of perovskite on the surface of the circuit substrate is smaller than the three-dimensional nucleation barrier of perovskite in solution to obtain a modified circuit substrate, perovskite crystals are grown on the surface of the modified circuit substrate of the circuit substrate to obtain the functional unit, heterogeneous nucleation and growth of perovskite on the circuit substrate are realized by reducing the nucleation barrier of perovskite on the surface of the circuit substrate and ensuring that the perovskite is smaller than the three-dimensional nucleation barrier of perovskite in solution, and then perovskite crystals are directly grown on the circuit substrate in situ, so that the attachment of perovskite crystals is realized by adopting a bonding process is avoided, and further, expensive bonding machines and ACF glue are avoided, and the problems of uneven distribution of conductive metal particles in ACF glue, bad points and uneven interface conductivity of different pixels and crystals are overcome.

Inventors

• TANG JIANG
• Niu guangda
• SONG ZIHAO

Assignees

• 华中科技大学鄂州工业技术研究院
• 华中科技大学

Dates

Publication Date

20260512

Application Date

20221230

Claims (3)

1. 1. A method of manufacturing an X-ray detector, the method comprising: Forming a modification layer on the surface of the circuit substrate so that the nucleation barrier of perovskite on the surface of the circuit substrate is smaller than the three-dimensional nucleation barrier of perovskite in solution, thereby obtaining a modified circuit substrate; immersing the modified circuit substrate in a perovskite crystal growth solution to grow perovskite crystals on the surface of the modified circuit substrate to obtain an X-ray detector, wherein the perovskite crystal growth solution is a FAPbBr 3 solution with the concentration of 1.27mol/L prepared by using N, N-dimethylformamide and gamma-butyrolactone=1:1 as mixed solvents; The mode of forming the modified layer comprises coating a modified material on the surface of the circuit substrate, and annealing; The modified material comprises at least one of PTAA and APTES, wherein the annealing temperature is 90-110 ℃, and the annealing time is 5-15min; The temperature of the perovskite crystal growth solution in the growing perovskite crystal is 45-55 ℃, and the temperature rising rate of the perovskite crystal growth solution in the growing perovskite crystal is 0.5-1.5 ℃ per hour; the method achieves in situ formation of perovskite crystals on circuit substrates by heterogeneous nucleation and growth without the need for subsequent bonding processes.
2. 2. The method of manufacturing an X-ray detector according to claim 1, wherein, The method for forming the modified layer comprises immersing the circuit substrate in a modified material, and/or The modified material has hydrophobicity, and/or The modified material has the ability to coordinate to perovskite.
3. 3. An X-ray detector, characterized in that the X-ray detector is manufactured by the method for manufacturing an X-ray detector according to any one of claims 1 to 2.

Description

X-ray detector, functional unit thereof and preparation method Technical Field The application relates to the technical field of semiconductor photoelectric detectors, in particular to an X-ray detector, a functional unit thereof and a preparation method thereof. Background Current X-ray imaging techniques can be divided into two types, indirect imaging and direct imaging. The indirect detection imaging is to utilize the scintillator to emit visible light randomly after being irradiated by X rays, and then to utilize the photoelectric detector to detect and image. The direct detection imaging is to absorb high-energy rays by utilizing a semiconductor material, then generate electron-hole pairs, directionally move under the action of an external electric field, and collect signals by an external circuit to realize signal detection. The direct detection imaging has no light scattering problem among different pixels, and has obvious theoretical advantage in resolution. Currently, the materials used for direct imaging detectors are classified into three types, one single crystal material, one polycrystalline material, and one amorphous material. Currently, when preparing direct imaging detectors using single crystal materials, perovskite crystals are typically prepared using either a solution process or a melt process, and then the crystals are affixed to the circuit substrate by a bonding process. The bonding process requires expensive bonders and ACF glue. The conductive metal particles inside the ACF paste may be unevenly distributed, with the risk of generating dead spots and uneven interface conductivity of different pixels and crystals. Disclosure of Invention The application provides an X-ray detector, a functional unit thereof and a preparation method thereof, which are used for providing a new path for attaching perovskite crystals on a circuit substrate so as to avoid using a bonding process. In a first aspect, the present application provides a method for preparing a functional unit, the method comprising: Modifying the surface of the circuit substrate to make the nucleation barrier of perovskite on the surface of the circuit substrate smaller than the three-dimensional nucleation barrier of perovskite in solution, thereby obtaining a modified circuit substrate; and growing perovskite crystals on the surface of the modified circuit substrate to obtain the functional unit. As an alternative embodiment, the modifying the surface of the circuit substrate to make the nucleation barrier of perovskite on the surface of the circuit substrate smaller than the three-dimensional nucleation barrier of perovskite in solution, to obtain a modified circuit substrate specifically includes: and forming a modification layer on the surface of the circuit substrate so that the nucleation barrier of perovskite on the surface of the circuit substrate is smaller than the three-dimensional nucleation barrier of perovskite in the solution, thereby obtaining the modified circuit substrate. As an alternative embodiment, the method for forming the modified layer comprises coating the surface of the circuit substrate with a modified material, annealing, and/or The method for forming the modified layer comprises immersing the circuit substrate in a modified material, and/or The modified material has hydrophobicity, and/or The modified material has the ability to coordinate to perovskite. As an alternative embodiment, the modifying material includes at least one of PTAA and APTES. As an alternative embodiment, the annealing temperature is 90-110 ℃, and/or The annealing time is 5-15min. As an alternative embodiment, the growing perovskite crystal on the surface of the modified circuit substrate to obtain the functional unit specifically includes: And immersing the modified circuit substrate in a perovskite crystal growth solution to grow perovskite crystals on the surface of the modified circuit substrate, thereby obtaining the functional unit. As an alternative embodiment, the perovskite crystal growth solution comprises at least one of perovskite with a chemical formula of ABX 3, wherein A is Cs +、MA+ or FA +, B is Pb 2+ or Sn 2+, and X is Cl -、Br- or I -. As an alternative embodiment, the perovskite growth solution in the growing perovskite crystals has a temperature of 45-55deg.C, and/or The temperature rising rate of the perovskite crystal growth solution in the growing perovskite crystal is 0.5-1.5 ℃ per hour. In a second aspect, the present application provides a functional unit manufactured using the method of manufacturing a functional unit according to the first aspect. In a third aspect, the application provides an X-ray detector comprising the functional unit of the second aspect. Compared with the prior art, the technical scheme provided by the embodiment of the application has the following advantages: The method provided by the embodiment of the application provides a new path for attaching perovskite crystals to a