Figure 1

Formation of Ge nanocrystallite clusters by thermally oxidizing poly-Si _0.85 Ge _0.15 pillars grown over buffer oxide. (a) Schematic diagram of the initially as-formed poly-SiGe pillars, (b) cross-sectional transmission electron microscopy (CTEM) micrograph of a self-assembled cluster of Ge nanocrystallites in the core of the oxidized pillars following 900°C 20 min oxidation in an H₂O ambient, and (c) enlarged CTEM micrograph of the Ge nanocrystallites.