Nanoscale, catalytically enhanced local oxidation of silicon-containing layers by 'burrowing' Ge quantum dots.

A new phenomenon of highly localized, nanoscale oxidation of silicon-containing layers has been observed. The localized oxidation enhancement observed in both Si and Si(3)N(4) layers appears to be catalyzed by the migration of Ge quantum dots (QDs). The sizes, morphology, and distribution of the Ge QDs are influenced by the oxidation of the Si-bearing layers.

Precise Ge quantum dot placement for quantum tunneling devices.

This study demonstrates the precise placement of Ge quantum dots (QDs) in an SiO2 or Si3N4 matrix in a self-organized manner by thermally oxidizing SiGe in nanostructures. The effectiveness of this method is shown by a variety of geometries including nanotrenches, nanorods and polygonal nanocavities. Modulating the structural geometry and peripheral spacer materials effectively places a single Ge QD in the center of an oxidized SiGe nanostructure or individual QDs at the corners (edges).