Wang Jing, Wang Yizhuo, Li Kuncai, Dai Xu, Zhang Liuyang, Wang Hong
Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, 710054, China.
School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an, 710054, China.
Adv Mater. 2022 Feb;34(5):e2106624. doi: 10.1002/adma.202106624. Epub 2021 Dec 18.
P-N junctions exist in many solid-state organic devices, such as light-emitting diodes, solar cells, and thermoelectric devices. Creating P-N junctions by bulk chemical doping in a single organic material (like silicon doped by boron and phosphorus) may capitalize the vast scientific and technological groundwork established in the inorganic semiconducting field. However, high-performance single-organic-material P-N junctions are seldom reported, because the diffusion of the dopant counterions often leads to transient rectification properties. Herein, a new type of lateral fully organic diodes created in single donor-acceptor (D-A) copolymer films with only one P-type dopant is reported. The achieved lateral devices exhibit high current densities of ≈3.83 A cm and a high rectification ratio of ≈2100, which are beyond the requirements for high-frequency identification tags. The P- to N-type polarity switching mechanism is proposed after spectroscopic and structural tests. Decent stability of the organic diode is obtained, which is due to the long channel length and low diffusion speed of the large size of dopants. This work opens the opportunities to create P-N junctions in ways of silicon-based inorganic semiconductors and promises new opportunities for integrating organic materials for flexible and printable organic devices.
P-N结存在于许多固态有机器件中，如发光二极管、太阳能电池和热电器件。通过在单一有机材料中进行体相化学掺杂来制造P-N结（如用硼和磷掺杂的硅），可以利用无机半导体领域已建立的大量科学技术基础。然而，高性能的单一有机材料P-N结鲜有报道，因为掺杂剂抗衡离子的扩散往往会导致瞬态整流特性。在此，报道了一种在仅含有一种P型掺杂剂的单一供体-受体（D-A）共聚物薄膜中制备的新型横向全有机二极管。所制备的横向器件表现出约3.83 A/cm的高电流密度和约2100的高整流比，这超出了高频识别标签的要求。经过光谱和结构测试后，提出了P型到N型的极性转换机制。由于大尺寸掺杂剂的长沟道长度和低扩散速度，获得了有机二极管良好的稳定性。这项工作为以硅基无机半导体的方式制造P-N结开辟了机会，并为集成有机材料用于柔性和可印刷有机器件带来了新的机遇。
