Naslov
Ion beam synthesis of buried Zn-VI quantum dots in SiO2: a GISAXS studies

Autori
Desnica-Franković, Ida-Dunja ; Desnica, Uroš ; Dubček, Pavo ; Buljan, Maja ; Bernstorff, Sigrid ; Karl, Helmut ; Stritzker, B.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Conference Book of the XII International Conference on Small-Angle Scattering : SAS 2002 / Carsughi, Flavio ; Spinozzi, Francesco - Venecija, 2002, 88-88

Skup
XII International Conference on Small-Angle Scattering : SAS 2002

Mjesto i datum
Venecija, Italija, 25.08.2002. - 29.08.2002

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
GISAXS; quantum dots; ion implantation; Zn-VI compounds

Sažetak
We have employed grazing incidence small angle x-ray scattering, GISAXS, in the study of ion beam synthesis of Zn-VI compound-semiconductor quantum dots, QDs, buried in the SiO2 matrix. The ZnTe and ZnS QDs were formed by successive ion implantation ?either single or multiple energy implants? of constituent atoms, at high ion doses (4?1016/cm2 and 7.6?1016/cm2) and subsequent annealing at different temperatures in the 800 ? 1100 oC range. Local Monodisperse Approximation (LMA) was used in the analysis of 2D GISAXS spectra, so that the average size and size distribution, the shape, the average inter-QD distance, and distance distribution, was determined as a function of implantation and thermal-treatment parameters. A dissimilar behavior under annealing was noticed for ZnTe and ZnS QDs, indicating unlike nanoparticle formation mechanisms. In Zn+Te-implanted SiO2, small nano-crystals are formed already during implantation, but the average particle size in subsurface layer remains similar up to Ta=800oC annealing. In contrast, much stronger annealing-temperature and annealing-time dependence of average size for Zn+S implanted samples is found. At higher annealing-temperatures, deeper in the samples, a bimodal size distribution of nano-particles is observed in both materials, which could be due to the combined effects of Ostwald ripening and enhanced diffusion in the irradiation-damaged surface layer. The study has highlighted GISAXS as a powerful technique in the quest for better control over the size, the size distribution and spacing of nanoparticles, leading to optimization of the unique properties of compound-semiconductors QDs and consequently development of functional semiconductor-nanocrystal based devices.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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