Reaction Paths for Self-Organized Surface Roughening of Silicon-Germanium Alloys During Hydride Gas-Source Molecular Beam Epitaxy

Si0.7Ge0.3(001) layers were grown at Ts = 450°C, where strain-induced roughening is completely quenched, to thicknesses greater than the critical value for misfit dislocation formation (tc ≃ 100 nm) to probe the effect of thetaH on cross-hatch formation. At t slightly larger than tc, surface roughness is dominated by single- and multiple-atomic-height steps associated with the interfacial misfits. The surface steps are preferential H desorption sites, thus the increased total step length results in a decrease in thetaH on terraces which increases RSiGe and allows higher adatom ascending step crossing probabilities which, driven by the inhomogeneous strain fields around the misfit dislocation clusters, contributes to the growth of periodic ridges.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Materials Science and Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Spila, Timothy Paul

Contributors dc:contributor

• Greene, Joseph E.

• Physics, Condensed Matter

Language dc:language

eng

Identifier

(MiAaPQ)AAI3030481

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/82711