Electrothermal feedback in Organic Devices (EFOD)

有机半导体通常具有低载流子迁移率，仅支持有限的电流密度。尽管如此，有机器件很容易达到焦耳自加热的水平，原因很简单，因为它们具有大面积和薄层厚度；后者在纳米范围内。与硅或砷化镓等标准无机半导体相比，它们在功率损耗和电导率之间显示出很强的正反馈，导致在相当低的正温度增量下就已经出现了热开关或负差分电阻(NDR)等非线性效应。本项目旨在演示和研究两种功能器件：有机发光二极管(OLED)和有机晶体管(OTS)中的这种非线性自加热效应。主要目标是对有机器件中的这些非线性过程有一个基本的了解，这对未来的器件和电路设计至关重要。在这个项目中，将根据所获得的基本见解，开发新的战略，以绕过焦耳自加热引起的限制。此外，还将探索电热反馈的作用，以开发未来的功能和应用于有机器件。

Organic semiconductors typically have low charge carrier mobility, supporting only limited current densities. Still, organic devices easily reach the level of Joule self-heating, simply because they have large area and thin layer thicknesses; the latter in the nanometer range. In contrast to standard inorganic semiconductors like silicon or gallium arsenide, they show a strong positive feedback between the power dissipation and the electrical conductivity, leading to nonlinear effects like thermal switching or negative differential resistance (NDR) happening already at fairly low positive temperature increments. This project aims to demonstrate and investigate such nonlinear self-heating effects in two functional device types: organic light-emitting diodes (OLEDs) and organic transistors (OTs). Key objective is a fundamental understanding of these nonlinear processes in organic devices, essential for future device and circuit design. Within this project, based on the fundamental insights gained, new strategies will be developed to circumvent limitations induced by Joule self-heating. In addition, the effect of electrothermal feedback will be explored to develop future functions and applications in organic devices.