Inhibiting strain-induced surface roughening: dislocation-free Ge/Si and Ge/SiGe core-shell nanowires

Irene A Goldthorpe; Ann F Marshall; Paul C McIntyre

doi:10.1021/nl9018148

Inhibiting strain-induced surface roughening: dislocation-free Ge/Si and Ge/SiGe core-shell nanowires

Nano Lett. 2009 Nov;9(11):3715-9. doi: 10.1021/nl9018148.

Authors

Irene A Goldthorpe¹, Ann F Marshall, Paul C McIntyre

Affiliation

¹ Materials Science and Engineering and Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, USA. oldthorpe@stanford.edu

PMID: 19795838
DOI: 10.1021/nl9018148

Abstract

Elastic strain is a critical factor in engineering the electronic behavior of core-shell semiconductor nanowires and provides the driving force for undesirable surface roughening and defect formation. We demonstrate two independent strategies, chlorine surface passivation and growth of nanowires with low-energy sidewall facets, to avoid strain-induced surface roughening that promotes dislocation nucleation in group IV core-shell nanowires. Metastably strained, dislocation-free, core-shell nanowires are obtained, and axial strains are measured and compared to elasticity model predictions.