Annealing effects on the microstructure of Ge/Si(001) quantum dots

Ge/Si(001) multilayer islands produced by gas-source molecular-beam epitaxy at 575 °C were investigated using energy-filtering transmission electron microscopy. Results show, for as-grown samples, not only a continuous enlargement of island size in upper layers but also a continuous increase of Ge c...

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Bibliografiska uppgifter
Huvudupphovsmän: Liao, X, Zou, J, Cockayne, D, Wan, J, Jiang, Z, Jin, G, Wang, K
Materialtyp: Journal article
Språk:English
Publicerad: 2001
Beskrivning
Sammanfattning:Ge/Si(001) multilayer islands produced by gas-source molecular-beam epitaxy at 575 °C were investigated using energy-filtering transmission electron microscopy. Results show, for as-grown samples, not only a continuous enlargement of island size in upper layers but also a continuous increase of Ge concentration within islands in upper layers. As a result of the increasing island size and Ge concentration within the islands, the island density in upper layers decreases. For samples annealed at 900 °C for 5 min, the aspect ratio of buried islands increases significantly, and the average Ge concentration within islands of different layers becomes uniform. © 2001 American Institute of Physics.