Two-Dimensional Amorphous Carbon with Tunable Atomic Structures As A Novel Dielectric Material for Advanced Electronic Applications

非技术描述最近开发的原子薄型电子材料可以改变目前建立在体硅上的半导体行业，并以其极大的厚度和独特的物理性能实现更强大的电子器件。然而，合成原子结构和电学性质可控的原子薄绝缘体是一个巨大的挑战。该研究项目旨在开发一种独特的工艺，从溶液可加工的前驱体制备原子薄的碳基绝缘子。它们的原子结构可以调整，以优化它们的性能，以适应不同要求的电子应用。所制备的绝缘薄膜的厚度可以精确地控制到原子分辨率，并且可以在整个半导体晶片表面形成具有良好的均匀性的薄膜。该项目的结果揭示了原子稀薄固体的结构-性质关系，这种固体缺乏有序的内部结构，在技术上可能导致更快、更强大、更便携的手机和计算机。该项目为来自代表性不足群体的当地高中生提供暑期研究实习机会，并帮助开发一个实践模块，重点是机器学习在本科生材料表征中的应用。该项目的目标是开发具有独特原子结构和材料特性的二维(2D)无定形碳，作为一种用于先进电子应用的新型和变革性介质材料。该项目首先开发了一种独特的工艺来制备具有中等有序度的可调的二维非晶碳单分子膜，该工艺基于具有固有的晶体-非晶核-壳结构的零维碳点的平铺和交联作为溶液可加工的先驱体。逐层沉积进一步实现了对原子分辨率的薄膜厚度的精确控制。科学地讲，原子薄的2D非晶碳的独特性质将与详细的原子结构相关联，结合了材料表征、高分辨率电子显微镜和密度泛函理论模拟。在技术上，2D非晶碳单分子层和多层膜被用作2D基于材料的晶体管和忆阻器的关键介电元件，以实现比基于块状金属氧化物的同类器件更高的器件性能和更低的可变性。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical DescriptionAtomically thin electronic materials developed recently could transform the current semiconductor industry built on bulk silicon and enable more powerful electronic devices with their extremely scaled thickness and unique physical properties. However, the synthesis of atomically thin insulators with controllable atomic structures and electrical properties is a significant challenge. This research projects seeks to develop a unique process to prepare atomically thin carbon-based insulators from solution-processable precursors. Their atomic structures can be adjusted to optimize their properties for different demanding applications in electronics. The thickness of the prepared insulating thin films can be precisely controlled down to atomic resolution, and they can be formed with excellent uniformity across the whole surface of semiconductor wafers. Results from this project shed light on the structure-property relationship for atomically thin solids that lacks an ordered internal structure, and could technologically lead to faster, more powerful, and more portable cell phones and computers. The project provides summer research internships for local high-school students from underrepresented groups and helps to develop a hands-on module with focus on the application of machine learning in material characterizations for undergraduates. These outreach opportunities prepare sustainable, adaptable, and globally competitive science and engineering workforce to benefit US economy.Technical DescriptionThe objective of this project is to develop two-dimensional (2D) amorphous carbon with unique atomic structures and material properties as a novel and transformative dielectric material for advanced electronic applications. The project starts from developing a unique process to prepare 2D amorphous carbon monolayer with tunable degree of medium range ordering, based on the tiling and cross-linking of zero-dimensional carbon dots with intrinsic crystalline-amorphous core-shell structure as solution-processable precursors. Layer-by-layer deposition further enables the precise control over the film thickness at atomic resolution. Scientifically, the unique properties of the atomically thin 2D amorphous carbon will be correlated with the detailed atomic structures combining material characterizations, high-resolution transmission electron microscopy, and density-functional theory simulation. Technologically, the 2D amorphous carbon monolayers and multilayers are used as the key dielectric component in 2D material-based transistors and memristors to enable enhanced device performance and reduced variability compared to their counterparts built on bulk metal oxides.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.