|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||2018 Symposium on Functional Nanomaterials: Discovery and Integration of Nanomaterials
||Site Selection by Epitaxial Group IV Quantum Dots on Patterned Si (001) Surfaces - the Roles of Lengthscales and Surface Morphology
||Jatin Amatya, Jerrold Floro
|On-Site Speaker (Planned)
Strain-driven self-assembly of heteroepitaxial Group IV quantum dots on Si (001) surfaces can be directed by imposed lithographic patterns. It is well-established that for discrete pits surrounded by (001) terraces, quantum dots homogeneously populate the pits as long as the surface diffusion length exceeds the inter-pit spacing. However, recent theories predict more complex behaviors when the surface is continuously height-modulated. We fabricated patterns having a programmed variation in morphology, across a range of periodicities relative to the intrinsic instability. Epitaxial growth of SiGe films on these patterns confirms aspects of the theory. For discrete pits, results are identical to the prevailing literature. However, for the pattern regions with continuous height modulation, SiGe quantum dots selectively form only on the saddle points. This remarkably requires that the dots bifurcate in volume, going from one dot per pit to two. Support by the National Science Foundation under award DMR-1410839 is gratefully acknowledged.
||Planned: Supplemental Proceedings volume