Thermally oxidized formation of new Ge dots over as-grown Ge dots in the Si capping layer
- State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433 (China)
- Materials Engineering, University of Queensland, Brisbane, Queensland QLD 4072 (Australia)
A Si-capped Ge quantum dot sample was self-assembly grown via Stranski-Krastanov mode in a molecular beam epitaxy system with the Si capping layer deposited at 300 deg. C. After annealing the sample in an oxygen atmosphere at 1000 deg. C, a structure, namely two layers of quantum dots, was formed with the newly formed Ge-rich quantum dots embedded in the oxidized matrix with the position accurately located upon the as-grown quantum dots. It has been found that the formation of such nanostructures strongly depends upon the growth temperature and oxygen atmosphere. A growth mechanism was proposed to explain the formation of the nanostructure based on the Ge diffusion from the as-grown quantum dots, Ge segregation from the growing oxide, and subsequent migration/agglomeration.
- OSTI ID:
- 22038803
- Journal Information:
- Journal of Applied Physics, Vol. 110, Issue 11; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Formation of uniform high-density and small-size Ge/Si quantum dots by scanning pulsed laser annealing of pre-deposited Ge/Si film
Annealing-induced change in quantum dot chain formation mechanism