Ion-beam synthesis of InSb nanocrystals in the buried SiO$_2$ layer of a silicon-on-insulator structure

The ion-beam synthesis of InSb nanocrystals in the buried SiO$_2$ layer of a silicon-on-insulator structure is investigated. The distributions of In and Sb atoms after annealing at a temperature of $T_a$ = 500–1100$^\circ$C are studied. It is established that the redistribution of implanted atoms is unsteadily dependent on the annealing temperature. The formation of InSb nanocrystals occurs at $T_a\ge$ 800$^\circ$C near the Si/SiO$_2$ interface and at a depth corresponding to the mean paths $R_p$. Analysis of the profiles of implanted atoms and of the structure and depth distribution of nanocrystals formed allows an inference regarding the two-stage character of formation of the InSb phase. In the initial stage, antimony precipitates are formed; further the precipitates serve as nuclei for indium and antimony to flow to them.