Collaborative Research: US-Ireland R&D Partnership: Processing-Driven Nucleation Mediated Control for Manufacturing of Phase-Pure Ferroelectric Hafnia

该奖项支持的研究将开发与电子材料制造相关的新知识，这些材料不会自然形成，但会显示出有用的特性。在这项工作中研究的材料是氧化铪，它可以有一种特定的原子排列，导致自发的电荷分离，这种分离可以通过施加足够的电压来改变。这个功能对未来几代的低功耗计算和计算机内存很有用。这种特殊的氧化铪结构的制备具有挑战性，并且通常包含具有其他原子排列的区域，这些区域不表现出有用的自发电荷分离特性。该奖项将支持基础研究，以提供直接和完全形成感兴趣的氧化铪结构所需的知识。这种新工艺将克服结构纯度的挑战，这种挑战阻碍了基于氧化铪的计算机存储设备的大规模生产，并使开发消耗更少功率的新计算元件成为可能。需要低功耗设备来降低与计算相关的总体能耗。这将直接影响美国经济、国家安全和社会，使新的微电子技术的开发和制造成为可能，从而实现新的功能和更低的能耗。该项目涉及美国、爱尔兰共和国和北爱尔兰的研究人员，他们代表了几个学科，包括材料科学、电子和扫描探针显微镜以及物理学。多学科和多国团队将开发教育推广材料，并将其呈现给经济落后地区的学生，以激发他们对科学、技术、工程和数学的兴趣，并展示科学和工程是如何全球性的努力。本基础研究项目的目标是开发一种可扩展的制造方法，通过原子层沉积制备相纯铁电氧化铪和氧化锆。该项目将利用等离子体增强原子层沉积技术制备氧化铪和氧化锆的非晶镀层。利用x射线衍射、扩展x射线吸收精细结构、透射电子显微镜、电子能量损失光谱、扫描探针显微镜和电学性能测量来表征加工参数对非晶结构和所产生相的影响。该项目将确定非晶结构键长和原子配位如何影响成核相。通过分离原子层沉积工艺参数对非晶结构的影响，然后确定其如何导致晶相形成，将产生一种制备相纯材料的确定方法。纳米级和器件级铁电行为将使用先进的显微镜进行量化，相杂质对材料性能的影响将被测量。最终的结果将是对非晶结构对氧化铪基材料结晶的影响以及相杂质对铁电性能的影响的新认识。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award supports research that will develop new knowledge related to the manufacturing of electronic materials that will not form naturally, but that exhibit useful properties. The material studied in this effort is hafnium oxide, which can have a specific arrangement of atoms that results in a spontaneous electric charge separation that can be changed with application of a sufficient voltage. This functionality is useful for future generations of low power computing and computer memory. This particular hafnium oxide structure is challenging to prepare and often contains regions with other atomic arrangements that do not exhibit the useful spontaneous charge separation property. This award will support fundamental research to provide the knowledge needed to directly and completely form the hafnium oxide structure of interest. This new process will overcome the challenges of structural purity that have hindered mass production of hafnium oxide-based computer memory devices and enable development of new computing elements that consume less power. Low power devices are needed to reduce the overall energy consumption related to computing. This will directly impact the US economy, national security, and society by enabling the development and manufacture of new microelectronic technologies that lead to new functionality and less energy consumption. This project involves researchers in the United States, the Republic of Ireland, and Northern Ireland, representing several disciplines, including materials science, electron and scanning probe microscopies, and physics. The multi-disciplinary and multi-national team will develop educational outreach materials and present them to students in economically disadvantaged areas to stimulate interest in science, technology, engineering, and mathematics and to show how science and engineering are global endeavors.The goal of this fundamental research project is to develop a scalable manufacturing method to prepare phase-pure ferroelectric hafnium oxide and hafnium zirconium oxide by atomic layer deposition. The project will utilize plasma-enhanced atomic layer deposition to prepare amorphous deposits of hafnium oxide and hafnium zirconium oxide. The impact of processing parameters on the amorphous structure and resulting phases will be characterized using X-ray Diffraction, Extended X-ray Absorption Fine Structure, Transmission Electron Microscopy, Electron Energy Loss Spectroscopy, Scanning Probe Microscopy, and electrical property measurements. The project will determine how amorphous structure bond length and atomic coordination impact the nucleating phase. By isolating the impact of atomic layer deposition process parameters on the amorphous structure and then determining how that leads to crystalline phase formation, a deterministic means to prepare phase-pure materials will result. The nano- and device-scale ferroelectric behavior will be quantified using advanced microscopies and the impact of phase impurities on material performance will be measured. The end result will be new knowledge of the impact of amorphous structure on crystallization of hafnium oxide-based materials and the impact of phase impurity on ferroelectric performance.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.