GOALI: Theoretical and Experimental Study of the Thermodynamic Stability of Amorphous Thin Films Based on Zirconia and Hafnia

非技术描述：半导体技术的持续小型化在很大程度上是美国在过去五十年中取得非凡经济进步的原因。今天，晶体管的设计正转向制造几纳米的器件，这只代表几百个原子间的距离。为了满足这种极其微小的设备的严格要求，必须发现、开发和引入新材料。该项目为在微电子学中使用非晶氧化铪薄膜作为栅极介电材料铺平了道路。这些电介质是绝缘体，以防止设备中紧密堆积的元件相互作用，从而降低效率。这个问题很复杂，需要进行理论和实验的联合研究，以找到稳定且具有必要电性能的材料。这个拓展项目旨在吸引高中女生学习物理科学。在与奥斯汀磁石高中的物理讲师和大量少数民族学生（LBJ科学院）的合作下，女学生有机会在德克萨斯大学做暑期研究。参与的科学家定期访问学校，并与广泛的学生观众互动。技术摘要：本项目旨在系统研究非晶氧化锆和半氧化锆的热力学稳定性，寻找通过掺杂价金属和氮来改变结晶温度和能量学的方法。二氧化铪（HfO2）是先进器件中取代二氧化硅（普通硅玻璃）作为栅极介电介质的主要候选者。重点是将材料的原子水平结构与其热力学联系起来，并通过这些知识阐明控制非晶相稳定性的实用方法。这是通过结合生长，结构和热力学表征和建模来实现的。Austin和Davis之间广泛的人员交流，以及与工业团体的积极合作，在第一原理理论和实验之间存在着非常密切的合作。将基础研究的技术应用牢记于心，也是教育组成部分的核心，重点关注物理、材料科学、化学和化学工程领域跨学科、跨机构的学生群体，他们参与了前沿研究，这自然与一个非常重要的技术问题有关。

NON-TECHNICAL DESCRIPTION: The continuous miniaturization of semiconductor technology is largely responsible for the extraordinary economic advances made by the US in the past fifty years. Today transistor design is moving into fabricating devices of a few nanometers, which represent just a few hundred inter-atomic distances. To meet the exacting requirements of such extraordinarily tiny devices, new materials have to be discovered, developed, and introduced. This project provides fundamental understanding to pave the way for using amorphous hafnium oxide films as gate dielectrics in microelectronics. These dielectrics are insulators to prevent the closely packed elements of the device from interacting with each other and becoming less efficient. The problem is complex and demands a joint theoretical and experimental study to find materials that are stable and have the necessary electrical properties. The outreach program is aimed at attracting girls in high school to physical sciences. In collaboration with the physics instructor at the Austin magnet high school with a large number of minority students (LBJ Science Academy) female students get an opportunity to do summer research at the University of Texas. The participating scientists visit the school regularly and interact with a broad student audience. TECHNICAL ABSTRACT: The goal of this project is to perform a systematic study of the thermodynamic stability of amorphous zirconia and hafnia, and find ways to alter the crystallization temperature and energetics by doping with aliovalent metals and nitrogen. Hafnium dioxide (HfO2) is the leading candidate to replace silicon dioxide (normal silica glass) as a gate dielectric in advanced devices. The focus is to relate the atomic level structure of the material to its thermodynamics, and through that knowledge elucidate practical means of controlling the amorphous phase stability. This is achieved through a combination of growth, structural and thermodynamic characterization and modeling. Very close collaboration exists between first principles theory and experiment with extensive exchange of personnel between Austin and Davis, as well as active collaborations with industrial groups. Keeping the technological application of fundamental research in mind is also central to the educational component focused on an interdisciplinary inter-institutional group of students in Physics, Materials Science, Chemistry, and Chemical Engineering involved in the cutting edge research, which naturally relates to a very important technological problem.