The impact of group-III vacancy diffusion, generated during dielectric cap induced intermixing, on the energy state transition and the inhomogeneity reduction in the InGaAs GaAs quantum-dot structure is investigated. We use a three-dimensional quantum-dot diffusion model and photoluminescence data to determine the thermal and the interdiffusion properties of the quantum dot. The band gap energy variation related to the dot uniformity is found to be dominantly affected by the height fluctuation. A group-III vacancies migration energy Hm for InGaAs quantum dots of 1.7 eV was deduced. This result is similar to the value obtained from the bulk and GaAs AlGaAs quantum-well materials confirming the role of SiO2 capping enhanced group-III vacancy induced interdiffusion in the InGaAs quantum dots.
|Physical Review B - Condensed Matter and Materials Physics
|Published - May 11 2006
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics