Ge-Sb-Te Phase Change Materials: Optical and Electronic Properties, Structural Transformations, and Fabrication of Nanostructures

该项目寻求新的知识和更基本的理解Ge-Sb-Te材料的晶体和非晶态的光学和电子性质，包括带隙的表征，电子带尾和缺陷态的能量分布，以及其他性质。结构研究，包括使用波动电子显微镜，旨在详细描述不同的非晶态（沉积态、部分退火态和熔体淬火态）的纳米结构，以及它们在相变动力学中的作用。该项目还将探索相变过程的纳米尺度尺寸限制（空间分辨率），目标是制造量子器件。该项目涉及具有高技术相关性的材料科学主题领域的基础研究问题。该研究将在基础水平上为材料科学的基础知识提供新的理解和电子/光子学能力。该研究与可重写CD/DVD和PRAM非易失性存储技术等应用有关。该计划的一个重要特点是通过培养学生在一个基础和技术上重要的领域的研究和教育的整合。该项目每年将资助两名研究生，并招收一到两名本科生，作为他们的毕业论文进行部分工作。因此，该项目将有助于教育和培训学士、硕士和博士毕业生。合格的学生将通过伊利诺伊大学伯克利分校的SURGE（工程领域代表性不足群体的支持）和WISE（科学和工程领域的女性）项目来确定。研究成果将通过在国际会议上的发言和在科学期刊上发表来广泛传播。＊＊＊

This project seeks new knowledge and greater fundamental understanding of the optical and electronic properties of crystalline and amorphous states of Ge-Sb-Te materials, including characterizations of the bandgap, energy distribution of electronic band tail and defect states, and other properties. Structural investigations, including the use of fluctuation electron microscopy, aim for detailed nanostructural description of the different amorphous states (as-deposited, partially annealed, and melt- quenched), and their role in phase change kinetics. The project will also explore the nanometer-scale size limit (spatial resolution) of the phase change process with a goal of fabricating quantum devices. %%%The project addresses basic research issues in a topical area of materials science having high technological relevance. The research will contribute basic materials science knowledge at a fundamental level to new understanding and capabilities in electronics/photonics. The research is relevant to applications such as rewritable CD/DVD and the PRAM nonvolatile memory technologies. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area. The program will support two graduate students and recruit one or two undergraduates per year to carry out portions of this work as their senior theses. This project will thus contribute to the education and training of B.S., M.S., and Ph.D. graduates. Qualified students will be identified through the SURGE (Support of Under-represented Groups in Engineering) and WISE (Women in Science and Engineering) programs which are in place at UIUC. Research results will be broadly disseminated by presentations at international conferences and by publication in scientific journals. ***