调制载流子输运维度提高室温有机磁阻的研究

Magnetoresistive devices are able to adjust their electrical properties in response to the change of magnetic fields, and thus have become critical components in various technologies including high-density information storage and sensitive monitoring. The magnetoresistance of organic semiconductors (OSCs) has caused a lot of attention in the past decade as they show noticeable magnetoresistance without the presence of ferromagnetic based electrodes, which increases its compatibility to general semiconductor industrial fabrication. However, research on achieving high room temperature organic magnetoresistance (OMR) has so far still been a challenge and difficulty. Herein, we propose a universal method to effectively increase the magnitude of room temperature OMR, that is, to modulate the dimensionality of charge carrier motions in OSCs. Based on our previous investigations on mechanisms behind OMR devices, this proposed approach should be relatively ready, practical, and low cost. Commercial OSC materials will be used. A variety of film-growth methods will be explored to monitor the one-dimensional charge carrier motion by achieving anisotropic OSC thin-films with high quality. The resulting OSC films will then be incorporated into functional devices, followed by OMR characterization at various driving conditions for device optimization. Reproducibility and scalability of successful OMR devices will be explored aiming at industrial production.

有机磁阻效应是一种新颖的磁阻效应。对有机磁阻效应发生和调控机制探索，过去十年来一直是国际磁阻领域研究热点之一。另外，有机磁阻器件无需磁性电极，在产业和应用领域能更好兼容通用半导体工艺和有机光电子器件，具有广阔应用潜力。然而，目前室温有机磁阻仍有待提高。如何有效增强室温有机磁阻依然是该领域的难点和有机磁阻效应应用关键，特别是增强室温有机磁阻的普适方法尚鲜见报道。本项目提出利用晶体对准生长技术调制载流子输运维度以提高室温有机磁阻的普适方案。我们将利用商用有机半导体材料和多样的薄膜生长手段，制备两种不同类型的有机自旋电子器件并进行表征；研究多种器件驱动条件下，有机磁阻效应受载流子输运维度调制；获得通过调制载流子输运维度增强室温有机磁阻的优化方案。通过项目的实施，不仅可加深对有机磁阻效应机制理解，获得增强室温有机磁阻的普适方法，还可为大规模制备室温有机磁阻器件提供基础。

有机磁阻（Organic magnetoresistance, OMR）器件无需磁性电极，在产业和应用领域能更好兼容通用半导体工艺和有机光电子器件，具有广阔应用潜力。然而，目前室温有机磁阻仍有待提高。如何有效增强室温有机磁阻依然是该领域的难点和有机磁阻效应应用关键，特别是增强室温有机磁阻的普适方法尚鲜见报道。本项目提出利用晶体对准生长技术调制载流子输运 维度以提高室温有机磁阻的普适方案。本项目首先研究了几类常用的有机半导体材料的物理机制，并探索和优化制备有机半导体（Organic Semiconductor, OSC）薄膜条件，实现OSC薄膜载流子迁移率高度各向异性，进而调制OSC载流子输运维度；利用上述薄膜制备两种代表性有机电子器件-二极管（Diode）和场效应管（Field-effect transistor, FET）开展载流子输运维度对器件性能调制作用机制研究，通过OSC薄膜材料和器件的制备优化，结合载流子输运维度调制增强OMR的机制研究，提炼增强室温OMR的普适方法，并形成稳定可靠的OMR器件制备技术。通过项目的实施，不仅可加深对有机磁阻效应机制理解，获得增强室温有机磁阻的普适方法，还可为大规模制备室温有机磁阻器件提供基础。