OPTICAL PHONONS IN InSb NANOCRYSTALS ION-BEAM SYNTHESIZED AT THE BONDING Si/SiO2 INTERFACE OF SILICON-ON-INSULATOR STRUCTURES
R. Zhang1,2, I. E. Tyschenko1, A. K. Gutakovskii1, V. A. Volodin1,2, V. P. Popov1
1A.V. Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
2Novosibirsk State Universit, Novosibirsk, Russia
Keywords: ion implantation, SiO, InSb, nanocrystals, optical phonons
Abstract
The properties of optical phonons in InSb nanocrystals synthesized at the Si/SiO2 interface of a silicon-on-insulator (SOI) structure are studied. The formation of InSb nanocrystals occurs as a result of diffusion of In and Sb atoms from implanted SiO2 and Si regions to the bonding interface of the SOI structure at annealing temperatures of 1000 and 1100 °C for 0.5-5 hours. The Raman spectra are excited by laser radiation with a wavelength λex = 514.5 nm at room temperature. The Raman scattering bands are observed in the spectra of the annealed structures whose position corresponds to the TO and LO modes in InSb. The effect of the high-frequency shift of the TO and LO modes in InSb nanocrystals is found, which reveals an inverse dependence on the annealing time as the temperature increases. The nature of the observed effect is related to deformations in nanocrystals. Non-hydrostatic deformations are present in nanocrystals formed after annealing at a temperature of 1000 °C. After annealing at a temperature of 1100 °C, deformations are present only at the initial stages of growth and are close to hydrostatic ones.
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