CN-121473004-B - Organic semiconductor longitudinal heterojunction monocrystalline array and preparation method thereof

CN121473004BCN 121473004 BCN121473004 BCN 121473004BCN-121473004-B

Abstract

The invention provides a longitudinal heterojunction single crystal array of an organic semiconductor and a preparation method thereof, wherein the preparation method comprises the steps of providing a first silicon column template, a second silicon column template and a substrate; the first silicon column template and the second silicon column template are respectively provided with a first silicon column array and a second silicon column array, the first silicon column template, the second silicon column template and the substrate are also respectively provided with a first alignment mark, a second alignment mark and a third alignment mark, and based on the difference of melting points of different organic semiconductor systems, the longitudinal heterojunction single crystal array with determined crystal orientation and controllable structure size is prepared through step-by-step melting, directional crystallization and alignment control. Compared with the traditional longitudinal heterojunction which is generally prepared layer by adopting a solution method, the method has the advantages that the solvent is easy to damage the first layer of crystals when the second layer of crystals are formed, the fractional crystallization is realized by utilizing the difference of melting points, the influence of the solvent on the first layer of crystals is avoided, and the method has the advantages of high controllability, good stability and strong applicability.

Inventors

Gao Qinghao
WANG YING
LI WEI
YANG JUNCHUAN
JIANG LEI

Assignees

中国科学技术大学苏州高等研究院
中国科学技术大学

Dates

Publication Date: 20260508
Application Date: 20260108

Claims (10)

1. The preparation method of the organic semiconductor longitudinal heterojunction single crystal array is characterized by comprising the following steps of: Providing a first silicon column template, a second silicon column template and a substrate; The first silicon column template comprises a first template body, wherein at least one first silicon column array is arranged on the first template body, the first silicon column array comprises a plurality of first silicon columns distributed in an array manner, the second silicon column template comprises a second template body, at least one second silicon column array is arranged on the second template body, the second silicon column array comprises a plurality of second silicon columns distributed in an array manner, the first silicon column array and the second silicon column array are arranged in a space symmetry manner, a plurality of filling through holes are formed in a substrate, the plurality of filling through holes are sequentially arranged at the same end of the substrate, and a first alignment mark, a second alignment mark and a third alignment mark are respectively arranged on the first template body, the second template body and the substrate; covering the substrate above the first silicon column templates, aligning the third alignment marks with the first alignment marks, pressing the substrate to enable the third alignment marks to be close to the first silicon column templates, enabling at least part of filling through holes to correspond to one ends of the first silicon columns one by one, adding first organic powder into the filling through holes, performing one-time melting treatment, forming a first single crystal micrometer line array in gaps between a plurality of first silicon columns and the substrate, and removing the first silicon column templates; Covering a substrate with a first single-crystal micro-wire array above the second silicon column template, enabling the first single-crystal micro-wire array to be close to the second silicon column template, aligning the third alignment mark with the second alignment mark, applying pressure to the substrate, enabling the third alignment mark to be close to the second silicon column template, enabling at least part of filling through holes to correspond to one end of the second silicon column one by one, adding second organic powder into the filling through holes, performing secondary melting treatment, forming a second single-crystal micro-wire array between a plurality of second silicon columns and the first single-crystal micro-wire array, and removing the second silicon column template to obtain a longitudinal heterojunction single-crystal array; the glass transition temperature of the first organic powder is greater than the glass transition temperature of the second organic powder.
2. The method for preparing a longitudinal heterojunction single crystal array of an organic semiconductor according to claim 1, wherein a first alignment mark on the first template body and a second alignment mark on the second template body are disposed in correspondence with each other, and the first alignment mark and the second alignment mark are identical in shape and size; and/or, in a first direction, the linear length of the first silicon pillar is greater than or equal to the linear length of the second silicon pillar; the first direction is the arrangement direction of the first silicon columns or the second silicon columns; And/or the linear lengths of the first silicon column and the second silicon column in the first direction are respectively and independently 1-10000 mu m; and/or the distance between two adjacent first silicon columns is 1-100 μm; and/or the distance between two adjacent second silicon columns is 1-100 μm.
3. The method for preparing a longitudinal heterojunction single crystal array of an organic semiconductor according to claim 1, wherein the provided first silicon pillar template and the second silicon pillar template are respectively subjected to asymmetric wettability modification, so that the top surfaces of the first silicon pillar and the second silicon pillar, which are far away from the first template body and the second template body, are hydrophilic, and the side wall surfaces are hydrophobic.
4. The method for preparing a longitudinal heterojunction single crystal array of an organic semiconductor according to claim 1, wherein the first alignment mark, the second alignment mark and the third alignment mark are all the same in shape and size; and/or the material of the substrate comprises at least one of glass, quartz, a silicon material or a silicon material deposited with a silicon oxide layer; And/or the plurality of filling through holes comprise at least two first filling through holes and at least two second filling through holes, the first filling through holes and the second filling through holes are sequentially and alternately arranged at the same end of the substrate at intervals, the first filling through holes are in one-to-one correspondence with the first silicon columns, and the second filling through holes are in one-to-one correspondence with the second silicon columns; And/or the first filling through hole and the second filling through hole are arranged side by side, or the orthographic projection of the first filling through hole on the vertical plane is not overlapped with the orthographic projection of the second filling through hole on the vertical plane, or at least part of orthographic projection of the first filling through hole on the vertical plane is overlapped with the orthographic projection part of the second filling through hole on the vertical plane; And/or the diameter of the first filling through hole is smaller than a first length, wherein the first length is the sum of the linear length of the first silicon columns in the first direction and the distance between two adjacent first silicon columns; the diameter of the second filling through hole is smaller than a second length, and the second length is the sum of the linear length of the second silicon columns in the first direction and the distance between two adjacent second silicon columns.
5. The method for producing a longitudinal heterojunction single-crystal array of organic semiconductor according to claim 1, wherein the glass transition temperature of the first organic powder is less than the self-decomposition temperature, and the glass transition temperature of the second organic powder is less than the self-decomposition temperature; The glass transition temperatures of the first organic powder and the second organic powder are smaller than the melting point of the substrate, and the glass transition temperatures of the first organic powder and the second organic powder are smaller than the melting points of the first silicon column template and the second silicon column template.
6. The method for preparing a longitudinal heterojunction single-crystal array of organic semiconductor according to any one of claims 1 to 5, wherein the primary melting treatment comprises a primary heating treatment after adding a first organic powder to the filling through hole, and continuously applying pressure to melt and spread the first organic powder along the surface of the first silicon pillars, and a secondary cooling to form the first single-crystal microwire array between a plurality of the first silicon pillars and the substrate; Adding second organic powder into the filling through hole, performing secondary heating treatment, continuously applying pressure to enable the second organic powder to be melted and spread along the surface of the second silicon column, performing secondary cooling, and forming a second single crystal micro-line array between a plurality of second silicon columns and the first single crystal micro-line array; and/or respectively adjusting the pressing pressure to realize thickness adjustment of the first single crystal microwire array and the second single crystal microwire array; and/or after the pressing is finished, the distance between the first silicon column or the second silicon column and the substrate is smaller than or equal to 1000nm.
7. The method for preparing a longitudinal heterojunction single-crystal array of an organic semiconductor according to claim 6, wherein the primary heating treatment comprises heating to a first temperature to melt the first organic powder, keeping the temperature again and continuously applying pressure to make the melted first organic powder form a melt which is fully spread on the surface of the first silicon column close to the substrate; The secondary heating treatment comprises the steps of firstly raising the temperature to a second temperature for the second time to melt the second organic powder, then preserving the heat for the second time and continuously applying pressure to enable the melt formed by the melted second organic powder to be paved on the surface of the second silicon column close to the first monocrystal micrometer line array; and/or, the primary cooling and the secondary cooling comprise a first-stage cooling and a second-stage cooling in sequence, and the cooling rate of the first-stage cooling is smaller than that of the second-stage cooling.
8. The method for preparing a longitudinal heterojunction single crystal array of an organic semiconductor according to claim 7, wherein the temperature rising rates of the primary temperature rising and the secondary temperature rising are respectively and independently 1-20 ℃/min; And/or the first temperature is greater than the glass transition temperature of the first organic powder and less than the thermal decomposition temperature of the first organic powder; the second temperature is greater than the glass transition temperature of the second organic powder and less than the thermal decomposition temperature of the second organic powder while being less than the glass transition temperature of the first organic powder; and/or the time of the primary heat preservation and the time of the secondary heat preservation are respectively and independently 5-60 min; and/or the cooling rate of the first-stage cooling is 0.1-1.0 ℃ per minute, and the cooling rate of the second-stage cooling is 1-10 ℃ per minute.
9. The organic semiconductor longitudinal heterojunction monocrystalline array is characterized in that the organic semiconductor longitudinal heterojunction monocrystalline array is prepared by the preparation method of the organic semiconductor longitudinal heterojunction monocrystalline array according to any one of claims 1-8, the organic semiconductor longitudinal heterojunction monocrystalline array comprises a substrate, a plurality of first monocrystalline microwires distributed in an array are arranged on the substrate, a second monocrystalline microwire is arranged on one side, far away from the substrate, of the first monocrystalline microwire, the first monocrystalline microwire and the second monocrystalline microwire are coaxially arranged, and the glass transition temperature of the first monocrystalline microwire is higher than that of the second monocrystalline microwire.
10. The organic semiconductor longitudinal heterojunction monocrystalline array according to claim 9, wherein a ratio of the heights of the first monocrystalline micro-wires to the second monocrystalline micro-wires is 1 (0.01-100); and/or the width of the first single crystal micro-wire is greater than the width of the second single crystal micro-wire; and/or the ratio of the width of the first single crystal micro wire to the width of the second single crystal micro wire is (1-100): 1.

Description

Organic semiconductor longitudinal heterojunction monocrystalline array and preparation method thereof Technical Field The invention belongs to the technical field of semiconductors, and relates to a longitudinal heterojunction monocrystalline array of an organic semiconductor and a preparation method thereof. Background The heterojunction is an interface structure formed by contacting two different semiconductor materials, and is characterized in that energy bands formed at the interface are aligned and built-in electric potential, so that the injection, separation and transmission behaviors of carriers can be effectively regulated. As one of the most core building blocks in optoelectronic devices, heterojunction enables efficient management of energy and charge through such interface barriers. In the field of inorganic semiconductors, heterojunction technology is widely applied to devices such as transistors, solar cells, light-emitting diodes and photodetectors, and response efficiency and stability of the devices are remarkably improved. In contrast, organic semiconductor materials have unique potential in realizing light, wearable and large-area optoelectronic devices due to the advantages of designable molecular structure, flexibility, low-cost processing and the like. Particularly, the organic semiconductor single crystal has highly ordered molecular stacking and extremely low defect density, so that the organic semiconductor single crystal is superior to a polycrystalline or thin film structure in carrier mobility, optical response and interface quality, and becomes an ideal material for constructing a high-performance organic heterojunction device. The preparation of the existing organic semiconductor monocrystal heterojunction generally depends on molecular structure design or specific interface interaction, and epitaxial growth or self-assembly forming of the heterojunction can be realized by adjusting and controlling molecular coplanarity, terminal substituent or energy level matching. However, such methods are often only suitable for specific molecular systems, have strict requirements on lattice matching, interface energy level and solvent conditions, have poor material universality, and are easy to generate interface pollution, inconsistent crystal orientation or structural damage in multi-step epitaxy or transfer process, so that high-precision array integration is difficult to realize. Disclosure of Invention Aiming at the defects existing in the prior art, the invention aims to provide a longitudinal heterojunction single crystal array of an organic semiconductor and a preparation method thereof, and the high-quality heterojunction is constructed by utilizing the difference of melting points of different organic materials and through fractional melting and directional crystallization. To achieve the purpose, the invention adopts the following technical scheme: In a first aspect, the invention provides a method for preparing a longitudinal heterojunction single crystal array of an organic semiconductor, comprising providing a first silicon column template, a second silicon column template and a substrate; the first silicon column template comprises a first template body, at least one first silicon column array is arranged on the first template body, and the first silicon column array comprises a plurality of first silicon columns distributed in an array manner; the second silicon column template comprises a second template body, at least one second silicon column array is arranged on the second template body, the second silicon column array comprises a plurality of second silicon columns distributed in an array mode, the first silicon column array and the second silicon column array are arranged in a space symmetrical mode, a plurality of filling through holes are arranged on the substrate, the plurality of filling through holes are sequentially arranged at the same end of the substrate, first alignment marks, second alignment marks and third alignment marks are respectively arranged on the first template body, the second template body and the substrate, the substrate is covered above the first silicon column template, the third alignment marks are aligned with the first alignment marks, the substrate is pressed to be close to the first silicon column template, at least part of filling through holes are in one-to-one correspondence with one ends of the first silicon columns, first organic powder is added into the filling through holes, and is subjected to primary melting treatment, a plurality of first silicon columns and the first silicon columns are in a clearance line to form a first monocrystalline column array, the first monocrystalline column array is close to the first monocrystalline column array, the micro-template is removed, and aligning the third alignment mark with the second alignment mark, applying pressure to the substrate to enable the third alignment mark to be close to th