Self-Organized Phases and Patterns in Epitaxial Film Systems

University Of Illinois At Chicago, Chicago IL

Investigators

Abstract

0010077 Wu This theoretical study addresses the formation of quantum dots and wires by self assembly. The study will address the effect of several fabrication parameters on the stability, growth and restructuring of thin multi-component solid films on single-component substrates. Surface and bulk diffusions appear to be two major mechanisms. The effort will begin with a re-derivation of the governing equations for thermochemical responses of multiphase solids under stress. The objective is to recapture the factors that have been heretofore thought to be negligible. More specifically, the theory will be reexamined for completeness and generality in chemical potential, with particular emphasis on the role of mismatch parameter. Analytical considerations will include, but not limited to, the morphological and compositional instabilities of multi-component solids, and the effect of substrate pattern generated by non-lithographic methods, such as the periodic strain field of a buried misfit dislocation network or a compliant substrate, on self-organization. The proposed investigation is expected to have a significant impact on the ongoing effort in producing nano-scale semiconductor islands of uniform size and distribution. Such self-organized small structures are thought to be the future of new electronic devices in just 15 or 20 years when conventional transistors and circuits can not be miniaturized further. In this way, the project will have contributed to the advance of another milestone technology, as well as to the understanding of a new phenomenon in the micron-to-nano range. ***