Reduction of Defects in Ultra-Thin SIMOX

本项目主要研究超薄SIMOX-SOI （Separation by植入式氧硅绝缘体）材料结构缺陷形成机制的基础问题，以及这些结构缺陷与工艺条件之间的关系。寻找缺陷形成的原因并提供有效的解决方案以最小化超薄层中的缺陷密度是一项重大挑战，通过对析出物扩散、生长和成熟过程的建模，将结构、化学和电学特性集成在一起，以获得更大的基本理解。这涉及(1)新设计的超薄SIMOX样品的微观结构和化学分析，采用透射电子显微镜（TEM），场发射扫描电子显微镜（FESEM），电子能量损失谱（EELS）和俄歇电子能谱复制（AES）；(2)通过C-V和I-V测量来测定埋藏氧化物的完整性；(3)深入了解缺陷的形成和生长机理；(4)通过识别控制缺陷形成和形成的因素，系统地评价缺陷形成与生长条件的关系；(5)对比退火前后样品，研究Si间质扩散特性；(6)模拟析出相生长和粗化过程。退火效应包括温度变化，退火时间，斜坡和冷却速率将被研究。现场实验将在TEM中进行，使用加热支架（高达1200℃）实时研究动态结构演变。该研究项目由亚利桑那大学材料科学与工程系和机械与航空航天工程系合作完成。该项目涉及与高技术相关的材料科学主题领域的基础研究问题。先进的表征技术可以更好地理解和控制SOI（绝缘体上硅）技术中涉及的基本过程，这将促进基础材料科学和技术的进步。从研究中获得的基本知识和理解有望为下一代微电子材料做出贡献。该计划的一个重要特点是通过在基础和技术重要领域培训学生，将研究和教育相结合。＊＊＊

This project addresses fundamental research issues in formation mechanisms of structural defects in ultra-thin SIMOX-SOI (Separation by IMplanted OXygen-Silicon On Insulator) materials and into the correlation between these structural defects and processing conditions. Finding the cause of defect formation and providing effective solutions to minimize defect density in ultra-thin layers are significant challenges, being approached by integrated structural, chemical, and electrical characterization with modeling of diffusional, growth, and ripening processes of precipitates to gain greater fundamental un-derstanding. This involves (1) microstructural and chemical analysis of newly designed ultra-thin SIMOX samples, by employing transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), electron energy loss spectroscopy (EELS) and Auger electron spectros-copy (AES); (2) determination of the buried oxide integrity by C-V and I-V measurements; (3) in-depth understanding of the formation and growth mechanisms of the defects; (4) systematic evaluation of the formation of defects as a function of growth conditions by identifying the factors that control defect formation and incorporation; (5) comparison of the samples before and after annealing to study the dif-fusion properties of Si interstitials; and (6) modeling of the precipitate growth and coarsening. An-nealing effects including temperature variations, annealing times, and ramping and cooling rates will be investigated. In situ experiments will be conducted in TEM by using a heating holder (up to 1200 C) to investigate the dynamic structural evolution in real-time. This research project is collaborative be-tween the Department of Materials Science and Engineering and the Department of Mechanical and Aerospace Engineering, University of Arizona.%%% The project addresses basic research issues in a topical area of materials science with high technologi-cal relevance. Advanced characterization techniques allow greater understanding and control of ele-mentary processes involved in SOI (silicon on insulator) technology which will allow advances in fun-damental materials science and technology. The basic knowledge and understanding gained from the research is expected to contribute to next generation microelectronic materials. An important feature of the program is the integration of research and education through the training of students in a funda-mentally and technologically significant area. ***