14 - Nanostructured Electronics and Optoelectronic Materials

Abstract

This chapter discusses the nanostructured electronics and optoelectronic materials. The availability of highly controlled deposition techniques and methods for nanometer-scale lithographic and device fabrications stimulated interest in the study of quantum size effects in the electronic and optical properties of nanostructures, ranging from one-dimensionally confined super lattices to three-dimensionally confined quantum dots. Super lattices and quantum wells were introduced as man-made quantum structures to engineer the quantum states for electrical and optical applications. It is appropriate to discuss what is needed for the realization of a man-made quantum system. To realize the quantum states in a given geometry, the size must be smaller or comparable to the coherence length of electrons, in order to exhibit quantum interference. This requirement eliminates doping as an effective means to achieve confinement, except at low temperatures, because doping comes from charge separation which results in barriers generally far exceeding the coherence length of electrons at room temperatures.