NSF-Europe: Distribution, Segregation & Dose-Loss of Dopants in Deca-Nanometer SOI Structures using Ab inito Interface Dopant Analysis by Transmission Electron Microscopy

这是德国、瑞典和美国的参与团体之间的合作项目。该项目致力于解决绝缘体上硅(SOI)结构中的基本材料科学问题，该结构与实现先进器件性能具有特别的技术相关性。该方法包括利用理论和实验工具确定十纳米SOI结构中杂质的分布和分离，以更好地了解导致纳米级器件结构中剂量损失和向两个氧化物界面分离的过程。实验方法将包括原子分辨率、基于电子显微镜的Z衬度和电子能量损失光谱。建模将由原子从头计算和过程建模组成。偏析研究的核心问题是，尽管进行了深入的研究，但硅/氧化物界面的原子结构仍然难以捉摸。在从头算材料模拟中，偏析能的模型依赖性通常被认为是一个缺点。人们计划利用这种模型依赖性，将其与分析电子显微镜相结合，将这一缺点转化为一种强大的表征工具，称为AIDA-TEM(透射式电子显微镜的从头算界面掺杂分析)。由于许多杂质和杂质的预测偏析位置在很大程度上依赖于界面的原子结构模型，因此许多杂质的偏析位置将首先通过实验确定。然后，将确定哪个原子界面模型与这些实验结果一致。通过这种方式，AIDA-TEM有助于确定界面结构、掺杂偏析行为和(从从头计算)电子性质，然后可以用于预测器件特性。基于实验和从头计算的工艺建模有望导致对掺杂剂再分布和剂量损失机制的理解。而结构-性质关系的知识，取决于掺杂剂和热处理条件，将允许确定更优化的器件工艺参数。该项目解决了与纳米电子学中具有技术相关性的材料相关的基础研究问题。该项目的一个重要特点是非常重视教育，强调研究与教育的结合，以及提供科学和教育益处的国际合作。工作人员和学生交流将补充参与小组之间的电子通信。参与该项目的本科生和研究生将接触到国际和世界级的科学技术。年轻的科学家和学生从这些项目中受益匪浅，学习纳米科学的基础知识，并有动力追求自己的新想法。该NSF项目由材料研究部(电子材料和陶瓷项目)和国际办公室(西欧)共同资助，作为NSF和欧洲在材料研究方面的合作活动(NSF 02-135)。该项目是在德国(德国埃尔兰根-纽伦堡大学电气和电子工程系Heiner Ryssel教授兼德国埃尔兰根弗劳恩霍夫集成电路研究所所长)和瑞典(瑞典皇家理工学院固态器件实验室微电子和信息技术系主任Mikael Ostling教授)的合作下实施的。

This is a collaborative project between participating groups in Germany, Sweden, and the US. The project addresses fundamental materials science issues in silicon-on-insulator (SOI) structures of particular technological relevance to realization of advanced device performance. The approach involves determination of the distribution and segregation of dopants within deca-nanometer SOI structures utilizing theoretical and experimental tools to gain greater understanding of processes leading to dose-loss and segregation to both oxide interfaces in nanoscale-device structures. Experimental methods will include atomic resolution TEM-based Z-contrast and electron energy-loss spectroscopy. Modeling will consist of atomistic ab initio calculations and process modeling. The core issue of segregation studies is that the atomic structure of silicon/oxide interfaces remains elusive in spite of intensive research. The model dependence of segregation energy in ab initio materials simulations is commonly considered to be a disadvantage. It is planned to exploit this model dependence by combining it with analytical TEM to transform a disadvantage into a powerful characterization tool, called AIDA-TEM (Ab initio Interface Dopant Analysis by Transmission Electron Microscopy). Since the predicted segregation sites of many impurities and dopants are heavily dependent on the atomic structure model of the interface, segregation sites of a number of impurities will first be determined experimentally. Then, which atomic interface model is in agreement with these experimental findings will be determined. In this way, AIDA-TEM helps to determine interface structure, dopant segregation behavior, and (from the ab initio calculations) electronic properties, which can then be used to predict device characteristics. Process modeling, based on experiments and ab initio calculations, is expected to lead to an understanding of dopant redistribution and dose loss mechanisms. And knowledge of structure-property relationships, dependent on dopants and annealing conditions, will allow determination of more optimum device processing parameters. %%% The project addresses fundamental research issues associated with materials having technological relevance in nanoelectronics. An important feature of the project is the strong emphasis on education, with emphasis on integration of research and education, and an international collaboration providing both scientific and educational benefits. Staff and student exchanges will supplement electronic communications between the participating groups. Undergraduate and graduate students involved in the project will be exposed to international and world-class science and technology. Young scientists and students greatly benefit from these kinds of projects, to learn the basics of nanoscience and to become motivated to pursue new ideas of their own. This NSF project is co-funded by the Division of Materials Research (Electronic Materials and Ceramics Programs), and the International Office (Western Europe) as a Cooperative Activity in Materials Research between the NSF and Europe (NSF 02-135). The project is being carried out in collaboration with participating groups in Germany (Heiner Ryssel Professor at the Electrical and Electronic Engineering Department, University of Erlangen-Nurnberg, Germany and Director of the Fraunhofer Institute of Integrated Circuits, Erlangen, Germany), and Sweden (Mikael Ostling Professor, Head of Department, Department of Microelectronics and Information Technology, Laboratory of Solid State Devices, KTH, Royal Institute of Technology).