EAGER: The Organic Permeable Base Transistor: A Nanoscale Organic Switch

非技术：有机晶体管有望实现柔性和低成本的电子产品。该领域的最新成果之一是有机可渗透基极晶体管。直到最近才发现，有机渗透基极晶体管达到非常高的输出电流，并在非常低的驱动电压下工作。然而，到目前为止，这种优异的性能是以显著的基极电流为代价的，导致静态功率损失，并且在大多数情况下排除了有机可渗透基极晶体管的使用。该项目解决了这一挑战。研究了基极电流的来源，并测试了抑制基极电流的方法。如果取得成功，有机晶体管的开关速度将提高一个数量级，这将加速柔性电子产品的商用化。此外，有机渗透基极晶体管基极电流的减小将开辟新的应用领域，如有源矩阵显示器的柔性背板。为了扩大该项目的影响，还采取了其他措施，旨在利用这项研究，并将其作为改善STEM教育的工具。PI将开发针对高中教师的课程，提供“大学学分加”课程。这些“大学学分加”课程允许高中生提前免费获得大学学分，这有可能增加STEM学位的入学率。此外，该提案的选定工作包将作为高级荣誉项目提供给物理和数学专业的学生。此外，研究生将接受社会重要研究领域的培训，这将使他们成为具有全球竞争力的劳动力的一部分。学生将参加与凯斯西储大学联合组织的暑期学校，为他们提供有机半导体、器件物理和器件工程的所有必要背景知识。技术：这个项目的目标是解开有机渗透基极晶体管中基极电流的起源。具体的研究目标是a)证明器件的漂移扩散模拟可以定量地再现器件的行为，特别是基极电流的大小，b)测试假设，即在基极电极顶部自组装的单层可以显着减少基极泄漏电流。漂移扩散模拟和实验之间的定量一致将通过对基电极的形态和有机可渗透基晶体管各层电荷输运的彻底表征来达成。特别是，多孔基极的生长和基极电流的性质将通过扫描探针方法、透射电子显微镜和测试设备的电特性来研究。自组织的绝缘膦酸层将生长在碱的顶部。电荷在这些层之间的传输将被量化和建模，从而导致在显着增加的电流放大下工作的有机可渗透基极晶体管的简明描述，从而降低静态功耗。作为该项目的结果，有机渗透基晶体管的实验验证模型将提供给科学界，这将大大提高对器件的基本理解，并将使有机渗透基晶体管的合理设计成为可能。此外，该项目将增加对多晶有机薄膜中垂直电荷传输的了解，并将为有机可渗透基晶体管中使用的标准材料提供详细的电荷载流子迁移率模型。澄清基极电流的性质将提高对注入无序有机半导体的理解，并将导致从氧化铝注入有机半导体C60的定量描述。

AbstractNontechnical:Organic Transistors hold the promise of enabling flexible and low-cost electronics. One of the latest additions to this field is the Organic Permeable Base Transistor. Only recently has it been found that Organic Permeable Base Transistors reach very high output currents and operate at very low driving voltages. However, until now this excellent performance has come at the expense of significant base currents leading to static power losses and ruling out the use of Organic Permeable Base Transistors in most cases.The project addresses this challenge. The origin of base currents is studied and approaches to suppress them are tested. If successful, the project will increase the switching speed of organic transistors by an order of magnitude, which will accelerate commercialization of flexible electronics. Additionally, the reduction of base currents of Organic Permeable Base Transistors will open new fields of application such as flexible backplanes for active matrix displays.To broaden the impact of the project, additional measures aim at leveraging the research and using it as a vehicle to improve STEM education. The PI will develop courses targeted at high school teachers offering "College Credit Plus" classes. These "College Credit Plus" classes allow high school students to earn college credit early and free of cost, which has the potential to increase the enrollment in STEM degrees. Furthermore, selected work-packages of the proposal will be offered as Senior Honors Project to a student majoring in physics and mathematics. Furthermore, graduate students will be trained in a socially important research area, which will make them part of a globally competitive workforce. Students will participate in a summer school jointly organized with Case Western Reserve University providing them with all necessary background in organic semiconductors, device physics, and device engineering.Technical:The goal of this project is to unravel the origin of base currents in Organic Permeable Base Transistors. The specific research objectives are a) to prove that a drift-diffusion simulation of the device can quantitatively reproduce the device behavior, in particular the magnitude of base currents and b) to test the hypothesis that a self-assembled monolayer on top of the base electrode can significantly reduce base leakage currents.A quantitative agreement between the drift-diffusion simulation and experiment will be reached by a thorough characterization of the morphology of the base electrode and of the charge transport in all layers of the Organic Permeable Base Transistor. In particular, the growth of the porous base electrode and the nature of base currents will be studied by scanning probe methods, transmission electron microscopy, and electrical characterization of test devices. Self-organized layers of insulating phosphonic acids will be grown on top of the base. Charge transport across these layers will be quantified and modeled, leading to a concise description of Organic Permeable Base Transistors operating at significantly increased current amplification and thus lower static power dissipation.As a result of the project, an experimentally validated model of the Organic Permeable Base Transistor will become available to the scientific community, which will significantly enhance the fundamental understanding of the device and will enable a rational design of Organic Permeable Base Transistors. Furthermore, the project will increase the knowledge on vertical charge transport in poly-crystalline organic films and will provide detailed charge carrier mobility models for standard materials used in Organic Permeable Base Transistors. Clarifying the nature of base currents will improve the understanding of injection into a disordered organic semiconductor and will lead to a quantitative description of injection from oxidized aluminum into the organic semiconductor C60.