Diffusion Studies and Defect Spectroscopy with Isotopically Controlled Semiconductors

该个人研究者奖将资助在原子水平上研究晶体元素和化合物半导体中的自输运和掺杂原子输运。由不同稳定同位素（例如28Si和30Si）组成的多层结构将被掺杂，使得平衡天然缺陷浓度不受掺杂过程的干扰。二次离子质谱法（SIMS）将用于直接和同时测量经过特定时间的热处理后，宿主晶体同位素和掺杂原子的浓度曲线作为深度的函数。对这些浓度分布的分析导致了对物质输运性质的定量理解。具体来说，控制物质输运的电荷态和原生缺陷的扩散率将被确定为温度和费米能级位置的函数。从这些研究中获得的知识将用于同位素控制半导体纳米结构的形成和研究。中子嬗变将允许在室温下掺杂这些晶体纳米粒子。在这项研究工作中确定的基本参数将直接有利于半导体纳米颗粒稳定性的理解和未来几代半导体器件的先进建模。研究生和本科生将密切参与这项研究的各个方面。半导体器件性能的不断提高，在很大程度上是由于器件尺寸的缩小以及随之而来的在芯片上放置更多功能的可能性。引入赋予半导体器件功能的掺杂原子，已经达到了极限，这只能通过在原子尺度上对掺杂原子输运的基础研究来克服。由于掺杂原子在空位和/或自间隙等天然缺陷的帮助下移动，因此同时测量掺杂原子和主体晶格原子的运动对于理解原子输运至关重要。这可以首次通过使用由宿主半导体晶体的不同同位素组成的晶体多层结构来实现。该个人研究者奖将支持使用二次离子质谱法测量半导体结构暴露于高温特定时间后的掺杂剂和同位素浓度谱的研究。这些研究的结果将为进一步了解未来半导体器件加工所需的物质传输参数和半导体纳米颗粒的稳定性奠定基础。从事本研究的研究生和本科生将获得在半导体行业和学术界具有挑战性的职位所需的培训

This individual investigator award will fund research focussing on self- and dopant atom transport in crystalline elemental and compound semiconductors at the atomic level. Multilayer structures consisting of different stable isotopes (e.g., 28Si and 30Si) will be doped such that the equilibrium native defect concentrations remain undisturbed by the doping process. Secondary ion mass spectrometry (SIMS) will be used to measure directly and simultaneously the concentration profiles of the host crystal isotopes and the dopant atoms as a function of depth after thermal treatment for specific times. Analysis of these concentration profiles leads to a quantitative understanding of matter transport properties. Specifically, the charge states and the diffusivity of the native defects controlling the matter transport will be determined as a function of temperature and the position of the Fermi level. The knowledge gained from these studies will be used in the formation and the study of isotopically controlled semiconductor nanostructures. Neutron transmutation will allow the doping of these crystalline nano particles at ambient temperature. The basic parameters to be determined in this research effort will benefit directly the understanding of the stability of semiconductor nano particles and the advanced modeling of future generations of semiconductor devices. Graduate and undergraduate students will be intimately involved in all aspects of this research.%%%The ever increasing performance of semiconductor devices is, in large part, due to the reduction in device dimensions and the concomitant possibility to place more functions on a chip. Introducing the dopant atoms which give semiconductor devices their functionality, is reaching limits which can only be overcome by a fundamental study of dopant atom transport at atomic dimensions. Because dopant atoms move assisted by native defects such as vacancies and/or self-interstitials, it is crucial for the understanding of the atomic transport to measure simultaneously the motion of the dopant and of the host lattice atoms. This can be achieved for the first time through the use of crystalline multilayer structures consisting of different isotopes of the host semiconductor crystal. This individual investigator award will support research using secondary ion mass spectrometry to measure dopant and isotope concentration profiles after exposure of the semiconductor structures to elevated temperatures for specific times. The results of these studies will form the basis for the advanced understanding of both matter transport parameters required for processing of future semiconductor devices and the stability of semiconductor nano particles. The graduate and undergraduate students performing this research will obtain the training required for challenging positions in the semiconductor industry and in academia.***