The curious case of exploding quantum dots: anomalous migration and growth behaviors of Ge under Si oxidation
1 Department of Electrical Engineering, National Central University, Chung-Li 320, Taiwan
2 Center for Nano Science and Technology, National Central University, Chung-Li 320, Taiwan
3 Zyomed Corporation, Altadena, California 91001, USA
Nanoscale Research Letters 2013, 8:192 doi:10.1186/1556-276X-8-192Published: 25 April 2013
We have previously demonstrated the unique migration behavior of Ge quantum dots (QDs) through Si3N4 layers during high-temperature oxidation. Penetration of these QDs into the underlying Si substrate however, leads to a completely different behavior: the Ge QDs ‘explode,’ regressing back almost to their origins as individual Ge nuclei as formed during the oxidation of the original nanopatterned SiGe structures used for their generation. A kinetics-based model is proposed to explain the anomalous migration behavior and morphology changes of the Ge QDs based on the Si flux generated during the oxidation of Si-containing layers.