Competing cluster growth: The Cu/Sn/Si(111) system

The phase separation competition of two thin film systems with a thermodyna mic propensity toward clustering was studied. Copper and tin bilayers of ap proximately 40 monolayer total thickness were deposited on Si(111) surfaces , then annealed at temperatures between 300 degreesC and 600 degreesC. At i ntermediate ratios of Sn and Cu amounts deposited, two different shapes of clusters coexist on the Si(111) surface, while Sn covers the Cu bearing str uctures at higher amounts, leading to an apparent Sn Ostwald ripening growt h dominated by a single characteristic length.