Research Rotation Project

Intermixing during SiGe heteroepitaxy

Jeff Drucker
Home Department - Physics
Areas of Study - Condensed Matter Experimental
Office - PSF 342
Phone - 4809659658
E-mail - jeff.drucker@asu.edu
Designation - Experimental

This project investigates the atomistic mechanisms for intermixing during semiconductor heteroepitaxy using SiGe as a model system. Intermixing during semiconductor heteroepitaxy can affect composition homogeneity, modify desired composition modulations, degrade interfacial abruptness and ultimately impact optical and electronic properties. As heterostructures become more complex, scale to eversmaller dimensions and incorporate composition modulations in all 3 dimensions, understanding and controlling intermixing assumes increasing importance. Any of a number of kinetic pathways may contribute to intermixing during growth or annealing. The relative importance of these individual processes are difficult to determine due to the (sub)nm legth scales involved. This project will assess the roles that surface diffusion and strain-enhanced bulk intermixing play in the composition evolution of both planar Si/Ge heterostructures and in heterostructures incorporating epitaxial Ge quantum dots. By forming sub-nm spatial resolution 3D composition maps we will correlate composition modulation with carefully controlled growth and annealing conditions. A combination of quantitative electron microscopy and composition selective etching/atomic force microscopy will be used to form the composition maps.